# ent

id: cord-001843-ceatyj3o
type: WORK_OF_ART
entity:
  Preliminary Study on Prevalence Risk Factor and Genetic Homogeneity of Porcine Reproductive and Respiratory Syndrome Virus in Registered Pig Farms


id: cord-002019-wtnf340p
type: PROTEIN
entity:
  DyLight 649 conjugated goat anti rabbit IgG antibody DyLight 488 conjugated goat anti rabbit IgG antibody DyLight 594 conjugated goat anti rabbit IgG antibody


id: cord-002177-yyfgl9x5
type: DNA
entity:
  FcRn 1286 5 ATGTGCCGTGGGTGTGGCCCTA 3 5 AACTTGCATCCCTGATAAGA 3 Co FcRn 1128 5 ATGGCTGTGGTATAGGCTGATA 3 5 CCTTTTTACAGCAATACATGCC 3


id: cord-002177-yyfgl9x5
type: PROTEIN
entity:
  chemokines cytokines proinflammatory enzymes adhesion molecules proinflammatory transcription factors


id: cord-002177-yyfgl9x5
type: DNA
entity:
  pFcRn primers 5 GGCGACGAGCACCACTACTG 3 and 5 AGCCGACCATGATTCCAACC 3 and GAPDH primers 5 ACATGGCCTCCAAGGAGTAAGA 3 and 5 GATCGAGTTGGGGCTGTGACT 3


id: cord-018078-clxzp1ph
type: PROTEIN
entity:
  Coronaviridae and Arteriviridae A comparative sequence analysis to revise the current taxonomy of the family Coronaviridae High frequency RNA recombination


id: cord-254735-8reu45yz
type: CHEMICAL
entity:
  N terminal peptide trimming Structural basis for antigenic peptide precursor processing by the endoplasmic reticulum aminopeptidase ERAP1 Structure of aminopeptidase N from Escherichia coli


id: cord-014697-aea67d8f
type: GGP
entity:
  vaccines 9 10 11 Today hepatitis B surface antigen 12 E coli heat labile enterotoxin LT B antigen 9 Norwalk virus capsid protein 8 VP1


id: cord-014697-aea67d8f
type: CHEMICAL
entity:
  B antigen 9 Norwalk virus capsid protein 8 VP1 antigen from foot and mouth disease virus 11 13 Cholera toxin B


id: cord-257116-6td3efjw
type: DISEASE
entity:
  RSV infected airway epithelial cells RSV exposed monocytes and virus specific antibodies Newcastle disease


id: cord-010045-eqzs01au
type: DNA
entity:
  Smal cut phosphatase treated M13mp10 Amersham International In addition various restriction endonuclease fragments


id: cord-010045-eqzs01au
type: CHEMICAL
entity:
  Cármenes R S Page K W Garwes D J Parral F title Sequence of the nucleoprotein gene from a virulent British field isolate of


id: cord-256444-grw5s2pf
type: DNA
entity:
  L leader sequence HE hemagglutinin esterase S spike E small membrane protein M integral membrane protein N nucleocapsid protein An poly A tail G


id: cord-256444-grw5s2pf
type: TAXON
entity:
  bovine coronavirus BCV turkey coronavirus TCV bluecomb virus feline coronavirus FCV canine coronavirus CCV


id: cord-256444-grw5s2pf
type: SO
entity:
  L leader sequence HE hemagglutinin esterase S spike E small membrane protein M integral membrane protein N nucleocapsid protein


id: cord-256444-grw5s2pf
type: CHEMICAL
entity:
  N linked glycosylation of the N terminal domain Identification of the coronavirus MHV JHM mRNA 4 product Complete sequence 20 kilobases of the polyprotein encoding gene 1 of


id: cord-263165-bv4dh9eu
type: EVENT
entity:
  Transmissible Gastroenteritis Virus TGEV Porcine Epidemic Diarrhea Virus PEDV and Hemagglutinating Encephalomyelitis Virus


id: cord-265224-mwgccr4a
type: PROTEIN
entity:
  N terminal sequencing NHz Ala Lys Gly Phe Tyr I1e Ser Lys Ala Leu Gly I1e Leu Gly I1e Leu Leu Gly Val Ala Ala Val Ala Thr I1e I1e Ala Leu Ser Val COOH


id: cord-285812-l7dpv6nx
type: DISEASE
entity:
  caecum colon liver pancreas snout Vith nasal conchae larynx trachea lymph nodes left tracheobronchial cranial mediastinal and mesenteric thymus spleen tonsil kidney bladder gonad thyroid adrenal skin


id: cord-269867-k10siwur
type: DNA
entity:
  VN1 559 CTTCAAGCAGTAACTAGTAACCCTAACGCG 582 NP2 562 CAAGCAGTAAACACTAGTCCTAACGCGGGC 585 PN3 565 GCAGTAAACCCTACTAGTAACGCGGGCAAT 588 NA4 tandem


id: cord-287266-sd5izamc
type: GO
entity:
  nuclear ribonucleoprotein SmD3 P2X purinergic receptor 7 RNA polymerase II transcription subunit 1 eukaryotic


id: cord-256316-1odgm6hm
type: DNA
entity:
  bovine enteric coronavirus BECV F15 mRNA 5 and mRNA 6 unique regions Influenza A virus M protein Monoclonal antibody


id: cord-256316-1odgm6hm
type: CHEMICAL
entity:
  N terminal part of the protein are needed for a definite assignment of the transmembrane orientation of ORF4 The possible role of the cysteine cluster


id: cord-256316-1odgm6hm
type: CHEMICAL
entity:
  Autographa californica nuclear polyhedrosis virus expression vectors The 1A protein of respiratory syncytial virus is an integral membrane protein present as multiple structurally distinct species Nucleotide sequence of the human coronavirus HCV 229E mRNA 4 and mRNA 5 unique regions Porcine respiratory coronavirus


id: cord-270586-ohs8z91m
type: PROTEIN
entity:
  S1 subunit porcine respiratory coronavirus VIIIth International Congress of Virolof the spike protein


id: cord-269094-6aka052v
type: FAC
entity:
  the Comisión Interministerial de Ciencia y Tecnología CICYT the Consejería de Educación y Cultura de la Comunidad de Madrid


id: cord-257136-zpeh8pmc
type: DNA
entity:
  PEDV R 2 0 998 Eff 96 04 PDCoV R 2 0 992 Eff 91 38 TGEV R 2 0 998 Eff 94 57 and PEAV R 2 0 999 Eff 98 60


id: cord-290640-kh2t0kfz
type: DNA
entity:
  Coronavirus TGEV Gene 3b date 2000 03 30 journal Virology DOI 10 1006 viro 2000 0218 sha 96454b22b4c649398a3d7763603fec0faa9beb4f doc_id 290640 cord_uid kh2t0kfz Abstract Gene 3b ORF 3b


id: cord-290640-kh2t0kfz
type: ORG
entity:
  the University of Tennessee College of Veterinary Medicine Center of Excellence Program for Livestock Diseases and Human Health


id: cord-269720-o81j3d1j
type: CELL_LINE
entity:
  X20 SSC X1 SSC 0 15 M NaCI 0 015 M trisodium citrate pH 7 0 for 18 hr and baked at 80 for 2 hr The membrane was boiled in 50 mM Tris HCl pH 8 0 for 5 min to remove glyoxal groups from the RNA


id: cord-288058-oilurica
type: GGP
entity:
  cells 3 2 0 8 Figure 6 Double immunofluorescence staining was further performed to assess the role of SA on TGEV replication TGEV Miller could infect both SA positive cells 1 7 0 3


id: cord-292019-rfu0bkag
type: DNA
entity:
  glycoprotein S gene sense primer 5Ј GCGCGGATCCATGAA AAACTATTTGTGG 3Ј antisense primer 5Ј GCGCGG TACCCGATGTGAAGCTATTG 3Ј Glycoprotein S mRNA


id: cord-315780-uhi66unn
type: CHEMICAL
entity:
  MgCl 0 1 gelatin 1 1 dNTPs 40 mM 1 1 Triton Xl00 lo 2 1 cDNA 0 5 1 of each primer 50 PM and 0 5 1 of TAq Polymerase 2 5 U


id: cord-296033-5zyoddl7
type: ORG
entity:
  the Centre of Virus Resource and Information Wuhan Institute of Virology Chinese Academy of Sciences Plasmids


id: cord-290282-oxyzndsj
type: PROTEIN
entity:
  light boxes 1b replicase 1b gene S spike gene E envelope gene M membrane gene N nucleoprotein gene Gene Rep 1b termination codon


id: cord-304014-k62mtr9j
type: PROTEIN
entity:
  TCONS_00002283 TCONS_00019226 TCONS_00019227 TCONS_00021915 TCONS_00037709 TCONS_00043977 TCONS_00052757 TCONS_00064461 TCONS_00067143


id: cord-304014-k62mtr9j
type: GGP
entity:
  PML ENSSSCT00000002141 Interferon Beta 1 IFNB1 ENSSSCT00000005691 Radical S Adenosyl methionine domain


id: cord-322238-8iwljdoi
type: CL
entity:
  stem lengths and cauliflower like structures with multiple loops formed by annealing between alternately inverted repeats of the target sequence


id: cord-322238-8iwljdoi
type: DISEASE
entity:
  Gastroenteritis Coronavirus TGEV strain H Porcine Reproductive and Respiratory Syndrome Virus PRRSV Pesudorabies PRV Porcine Parvovirus


id: cord-297398-40bshqly
type: GGP
entity:
  p38 mitogen activated protein kinase pathways date 2019 11 18 journal Antiviral Res DOI 10 1016 j antiviral 2019 104651 sha 44ce728e9777a6644404a15f6945116b189f3c17 doc_id 297398 cord_uid 40bshqly Emerging coronaviruses CoVs


id: cord-346643-os2kyvvf
type: DNA
entity:
  membrane gene date 2016 11 15 journal Virus Genes DOI 10 1007 s11262 016 1409 8 sha 8375539936b6724e16526afef18b9902fdbf97b6 doc_id 346643 cord_uid os2kyvvf The membrane M protein


id: cord-317462-nvrl0vyi
type: CHEMICAL
entity:
  MgCl 2 2 L 10 RT Buffer 1 L RNase Free dH 2 O 4 75 L dNTP Mixture 1 L RNase Inhibitor 0 25 L AMV Reverse Transcriptase 0 5 L Random 9 mer 0 5 L antisense primer 0 5 L


id: cord-315688-ba5dus2j
type: PROTEIN
entity:
  nucleoprotein N and five nonstructural proteins replicase 1a 1b 3a 3b and protein 7 14 15 16 The genome


id: cord-317496-6o2upns3
type: CHEMICAL
entity:
  oligonucleotides Pac S VS 5 GGATTAATTAAGAAGGGTAAGTTGCTCATTAGAAATAATGGTAAGTTACTAAACTTTGGTAA CCACTTCGTTAACACACCATGAAGTCTTTAACCTAC 3 PacI restriction site in


id: cord-345651-admlzeu4
type: ORG
entity:
  The N Terminal Domain of Spike Protein Is Not the Enteric Tropism Determinant for Transmissible Gastroenteritis Virus


id: cord-312210-3x9s3g8n
type: ORG
entity:
  the Federation of Animal Science Societies Guide for the Care and Use of Agricultural Animals in Research and Teaching the USDA Animal Welfare Act and Animal Welfare Regulations


id: cord-329819-dpgexphf
type: PROTEIN
entity:
  rabbit anti human EGFR rabbit anti human phospho EGFR Tyr1068 rabbit anti human AKT rabbit anti human phospho AKT rabbit anti human phospho ERK1 2


id: cord-329819-dpgexphf
type: ORG
entity:
  the Priority Academic Program Development of Jiangsu Higher Education Institutions PAPD Supplementary


id: cord-300436-beb8k075
type: PROTEIN
entity:
  Dylight 633 conjugated goat anti rabbit IgG red and FITC conjugated anti TGEV polyclonal antiserum green


id: cord-313126-7hrjzapj
type: WORK_OF_ART
entity:
  Diagnosis to Detect Porcine Transmissible Gastroenteritis Virus TGEV by Optical and Transmission Electron Microscopy Techniques Complete


id: cord-342289-zpstb7h9
type: PROTEIN
entity:
  smooth muscle actin antibodies Dako mouse monoclonal anti human desmin antibodies Dako sheep polyclonal anti human fibronectin antibodies


id: cord-342289-zpstb7h9
type: ORG
entity:
  Human Intestinal Enteroids a New Model To Study Human Rotavirus Infection Host Restriction and Pathophysiology Replication


id: cord-341015-45kbggzk
type: PROTEIN
entity:
  Nidoviruses DOI 10 1007 978 0 387 33012 9_12 sha 367b90c94369b02ee90d8d046f8f248b6867e602 doc_id 341015 cord_uid 45kbggzk nan


id: cord-328935-mn8r972x
type: DNA
entity:
  influenza virus hemagglutinin gene Equine influenza virus infections an update Probiotic bacteria enhance murine


id: cord-328935-mn8r972x
type: DISEASE
entity:
  diseases of the respiratory reproductive and gastrointestinal tracts of domestic animals and poultry


id: cord-337645-t6py0oyw
type: DNA
entity:
  simian virus 40 SV40 rotavirus enterovirus and rhinovirus Suzuki and Suzuki 2006 The binding of enveloped viruses to specific cellular receptors


id: cord-354904-7gq2e6f0
type: ORG
entity:
  the Museum of Strains of the Laboratory of Virology Scientific Research Veterinary Institute Russian Academy of Sciences Saratov


id: cord-355499-5vj3oasa
type: ORG
entity:
  Transmissible Gastroenteritis Virus TGEV Infection Alters the Expression of Cellular MicroRNA Species That Affect Transcription of TGEV Gene 7 date 2015 06 07


id: cord-346928-g1dqiki6
type: DNA
entity:
  S gene 1 13 25 Four respiratory 7 19N 1 2 7 23N 2 1 12 19N 3 1 16 19N 2 1 and 5 fecal 7 19F 1 1 12 19F 2 1 16 19F 2 1 14 23F 1 1 24 23F 3 1 strains


id: cord-348896-a2mjj5dt
type: WORK_OF_ART
entity:
  Viral Infections of the Gastrointestinal Tract Viral Diarrhea of Man and Animals Diseases of Swine Diseases of Swine


# bib

id: cord-001591-4ic2in3i
author: Hu, Xiaoliang
date: 2015-03-21
txt: ./txt/cord-001591-4ic2in3i.txt
cache: ./cache/cord-001591-4ic2in3i.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4379598/
doi: 10.1186/s12917-015-0387-8
summary:
  The detailed analysis of the genetic variation of TGEVs in China provides essential information for further understanding the evolution of TGEVs. Transmissible gastroenteritis virus (TGEV) is the etiological agent of transmissible gastroenteritis (TGE), and it can cause viral enteritis and severe diarrhea with high morbidity in pigs of all ages, as well as high mortality in suckling piglets [1] . Nucleotide sequence analysis indicated that there were no deletions or insertions in the ORF1ab region of the Miller 6 and Purdue TGEV strains. A 6-nt deletion was found in the S gene at nt 1,123-1,128 of the TGEV-HX, SC-Y, and WH-1 strains, which caused the S protein to be two amino acids shorter than those of the Purdue, Miller 6, TS, H16 and H165 strains (Figure 2A) . Two amino acid changes at the N-Terminus of transmissible gastroenteritis coronavirus spike protein result in the loss of enteric tropism

title:
  Molecular characterization and phylogenetic analysis of transmissible gastroenteritis virus HX strain isolated from China

abstract:
  BACKGROUND: Porcine transmissible gastroenteritis virus (TGEV) is the major etiological agent of viral enteritis and severe diarrhea in suckling piglets. In China, TGEV has caused great economic losses, but its role in epidemic diarrhea is unclear. This study aims to reveal the etiological role of TGEV in piglet diarrhea via molecular characterization and phylogenetic analysis. RESULTS: A TGEV-HX strain was isolated from China, and its complete genome was amplified, cloned, and sequenced. Sequence analysis indicated that it was conserved in the 5′ and 3′-non-translated regions, and there were no insertions or deletions in nonstructural genes, such as ORF1a, ORF1b, ORF3a, ORF3b, and ORF7, as well as in genes encoding structural proteins, such as the envelope (E), membrane (M), and nucleoprotein (N) proteins. Furthermore, the phylogenetic analysis indicated that the TGEV-HX strain was more similar to the TGEV Purdue cluster than to the Miller cluster. CONCLUSIONS: The present study described the isolation and genetic characterization of a TGEV-HX strain. The detailed analysis of the genetic variation of TGEVs in China provides essential information for further understanding the evolution of TGEVs.


id: cord-001843-ceatyj3o
title: Ultrasensitive Detection of RNA and DNA Viruses Simultaneously Using Duplex UNDP-PCR Assay
author: Huang, Yong
date: 2015-11-06
txt: ./txt/cord-001843-ceatyj3o.txt
cache: ./cache/cord-001843-ceatyj3o.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4636378/
doi: 10.1371/journal.pone.0141545
summary:
  PCV2 DNA and TGEV RNA were simultaneously released from the serum sample by boiling with lysis buffer, then magnetic beads and gold nanoparticles coated with single and/or duplex specific probes for TGEV and PCV2 were added to form a sandwich-like complex with nucleic acids released from viruses. This duplex UNDP-PCR assay could detect TGEV (RNA virus) and PCV2 (DNA virus) from large-scale serum samples simultaneously without the need for DNA/RNA extraction, purification and reverse transcription of RNA, and showed a significantly increased positive detection rate for PCV2 (29%) and TGEV (11.7%) preclinical infection than conventional duplex PCR/RT-PCR. The duplex UNDP-PCR assay is suitable for simultaneous detection of RNA and DNA viruses in early viral infection, providing an effective approach for diagnosis of swine diseases. The duplex UNDP-PCR assay developed in this study provided a useful tool for simultaneous detection of RNA (TGEV) and DNA viruses (PCV2) without the need for viral nucleic acid extraction, purification and reverse transcription.

abstract:
  Mixed infection of multiple viruses is common in modern intensive pig rearing. However, there are no methods available to detect DNA and RNA viruses in the same reaction system in preclinical level. In this study, we aimed to develop a duplex ultrasensitive nanoparticle DNA probe-based PCR assay (duplex UNDP-PCR) that was able to simultaneously detect DNA and RNA viruses in the same reaction system. PCV2 and TGEV are selected as representatives of the two different types of viruses. PCV2 DNA and TGEV RNA were simultaneously released from the serum sample by boiling with lysis buffer, then magnetic beads and gold nanoparticles coated with single and/or duplex specific probes for TGEV and PCV2 were added to form a sandwich-like complex with nucleic acids released from viruses. After magnetic separation, DNA barcodes specific for PCV2 and TGEV were eluted using DTT and characterized by specific PCR assay for specific DNA barcodes subsequently. The duplex UNDP-PCR showed similar sensitivity as that of single UNDP-PCR and was able to detect 20 copies each of PCV2 and TGEV in the serum, showing approximately 250-fold more sensitivity than conventional duplex PCR/RT-PCR assays. No cross-reaction was observed with other viruses. The positive detection rate of single MMPs- and duplex MMPs-based duplex UNDP-PCR was identical, with 29.6% for PCV2, 9.3% for TGEV and 3.7% for PCV2 and TGEV mixed infection. This duplex UNDP-PCR assay could detect TGEV (RNA virus) and PCV2 (DNA virus) from large-scale serum samples simultaneously without the need for DNA/RNA extraction, purification and reverse transcription of RNA, and showed a significantly increased positive detection rate for PCV2 (29%) and TGEV (11.7%) preclinical infection than conventional duplex PCR/RT-PCR. Therefore, the established duplex UNDP-PCR is a rapid and economical detection method, exhibiting high sensitivity, specificity and reproducibility.


id: cord-002019-wtnf340p
author: Chen, Xiaojuan
date: 2016-04-15
txt: ./txt/cord-002019-wtnf340p.txt
cache: ./cache/cord-002019-wtnf340p.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4832189/
doi: 10.1038/srep24152
summary:
  We demonstrated that elevated numbers of gut-homing CD8(+) T cells (which express α4β7 and CCR9 molecules) were presented in porcine inguinal lymph nodes and were recruited to the small intestine by RA. Taken together, the cell migration assay results revealed a strong chemotactic response in T cells when activated by RA-activated DCs. These data demonstrated that RA-pretreated BMDCs could activate T cells to express high functional levels of the gut-homing receptor CCR9, as well as to migrate towards the porcine chemokine CCL25. In agreement with the migration of gut-homing CD8 + cells, our observations showed that after RA plus TGEV s.c. treatment, many CD3 + T cells were recruited to the intestinal villi and lamina propria, and these data also showed that RA-assisted antigen s.c. can establish a stronger and faster cellular immune response to defend against foreign pathogens 40 .

title:
  Retinoic acid facilitates inactivated transmissible gastroenteritis virus induction of CD8(+) T-cell migration to the porcine gut

abstract:
  The digestive tract is the entry site for transmissible gastroenteritis virus (TGEV). TGEV transmission can be prevented if local immunity is established with increased lymphocytes. The current parenteral mode of vaccination stimulates systemic immunity well, but it does not induce sufficient mucosal immunity. Retinoic acid (RA) plays an important role in the induction of cells that imprint gut-homing molecules. We examined whether RA assist parenteral vaccination of pigs could improve mucosal immunity. We demonstrated that elevated numbers of gut-homing CD8(+) T cells (which express α4β7 and CCR9 molecules) were presented in porcine inguinal lymph nodes and were recruited to the small intestine by RA. Intestinal mucosal immunity (IgA titre) and systemic immunity (serum IgG titre) were enhanced by RA. Therefore, we hypothesized that RA could induce DCs to form an immature mucosal phenotype and could recruit them to the small intestinal submucosa. Porcine T-cells expressed β7 integrin and CCR9 receptors and migrated to CCL25 by a mechanism that was dependent of activation by RA-pretreated DCs, rather than direct activation by RA. Together, our results provide powerful evidence that RA can assist whole inactivated TGEV (WI-TGEV) via subcutaneous (s.c.) immunization to generate intestinal immunity, and offer new vaccination strategies against TGEV.


id: cord-002177-yyfgl9x5
title: TGEV infection up-regulates FcRn expression via activation of NF-κB signaling
author: Guo, Jinyue
date: 2016-08-24
txt: ./txt/cord-002177-yyfgl9x5.txt
cache: ./cache/cord-002177-yyfgl9x5.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4995372/
doi: 10.1038/srep32154
summary:
  Furthermore, treatment of TGEV-infected IPEC-J2 cells with the NF-κB-specific inhibitor BAY 11-7082 resulted in down-regulation of pFcRn expression. We identified four NF-κB transcription factor binding sites in the promoter region of this gene using luciferase reporter system, chromatin immunoprecipitation, electromobility shift assay, and supershift analysis. In the present study, we investigated how TGEV infection activated the NF-κ B pathway in vitro and up-regulated pFcRn expression in IPEC-J2 cells. Furthermore, pFcRn expression induced by TGEV infection was strongly reduced by the NF-κ B-specific inhibitor BAY 11-7082 in IPEC-J2 cells (Fig. 3) . Transient transfection of the pFcRn promoter luciferase reporter plasmids revealed that pFcRn-luc-(1-3) plasmids resulted in increased promoter activity in the presence of TGEV infection (Fig. 4B) , further demonstrating that TGEV up-regulates pFcRn expression in IPEC-J2 cells. In summary, TGEV infection up-regulates pFcRn expression in IPEC-J2 cells, and activates the NF-κ B signaling pathway.

abstract:
  It has been well characterized that the neonatal Fc receptor (FcRn) transports maternal IgG to a fetus or newborn and protects IgG from degradation. We previously reported that FcRn is expressed in a model of normal porcine intestinal epithelial cells (IPEC-J2). Transmissible gastroenteritis is an acute enteric disease of swine that is caused by transmissible gastroenteritis virus (TGEV). How porcine FcRn (pFcRn) expression is regulated by pathogenic infection remains unknown. Our research shows that IPEC-J2 cells infected with TGEV had up-regulated pFcRn expression. In addition, the NF-κB signaling pathway was activated in IPEC-J2 cells by TGEV infection. Furthermore, treatment of TGEV-infected IPEC-J2 cells with the NF-κB-specific inhibitor BAY 11-7082 resulted in down-regulation of pFcRn expression. Transient transfection of pFcRn promoter luciferase report plasmids with overexpression of NF-κB p65 transcription factor enhanced the activation of the luciferase report plasmids. We identified four NF-κB transcription factor binding sites in the promoter region of this gene using luciferase reporter system, chromatin immunoprecipitation, electromobility shift assay, and supershift analysis. Together, the data provide the first evidence that TGEV infection up-regulates pFcRn expression via activation of NF-κB signaling.


id: cord-003976-05tf6oqa
author: Wang, Kai
date: 2019-11-06
txt: ./txt/cord-003976-05tf6oqa.txt
cache: ./cache/cord-003976-05tf6oqa.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6851170/
doi: 10.3389/fmicb.2019.02540
summary:
  Lp-1s could induce large amounts of interferon-β in IPEC-J2 cells in the early stage (6 h) of infection with TGEV, and increased the level of phosphorylated signal transducer and activator of transcription and its nuclear translocation in the late stage (24–48 h) of infection. We found that the mRNA expression levels of ZAP, MX2, MX1, PKR, OASL, and ISG15 were significantly higher in the Lp-1s treated group than in the TGEV infected group at various points after infection. In the present study, we found that IPEC-J2 cells still produced IFN-β after infection with TGEV, which increased with time, (F) Relative expression of p-STAT1/STAT1 in Lp-1s treatment group was significantly higher than TGEV infected alone at 24 h ( * P < 0.05). The induced level of IFN-β in Lp-1s-treated IPEC-J2 cells was significantly different from that in the TGEV infected group at the same time point.

title:
  Anti-TGEV Miller Strain Infection Effect of Lactobacillus plantarum Supernatant Based on the JAK-STAT1 Signaling Pathway

abstract:
  Transmissible gastroenteritis (TGE), caused by transmissible gastroenteritis virus (TGEV), is one many gastrointestinal inflections in piglets, characterized by diarrhea, and high mortality. Probiotics are ubiquitous bacteria in animal intestines, which have many functions, such as promoting intestinal peristalsis and maintaining the intestinal balance. We found that the supernatant of the Lp-1 strain of Lactobacillus plantarum, isolated in our laboratory, and named Lp-1s had marked anti-TGEV effect on IPEC-J2 cells. Lp-1s could induce large amounts of interferon-β in IPEC-J2 cells in the early stage (6 h) of infection with TGEV, and increased the level of phosphorylated signal transducer and activator of transcription and its nuclear translocation in the late stage (24–48 h) of infection. This resulted in upregulated expression of interferon-stimulated genes, and increased the transcription and protein expression of antiviral proteins, resulting in an anti-TGEV effect.


id: cord-004729-nmkilkcx
author: Reynolds, D. J.
date: 1979
txt: ./txt/cord-004729-nmkilkcx.txt
cache: ./cache/cord-004729-nmkilkcx.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7086778/
doi: 10.1007/bf01348032
summary:
  No clinical disease resulted but infectious virus was isolated from faeces for up to 22 days after infection and serum antibody was detected by neutralisation and immunofluorescence tests. No clinical disease resulted but infectious virus was isolated from faeces for up to 22 days after infection and serum antibody was detected by neutralisation and immunofluorescence tests. Control and infected animals were tested for TGEV excretion by attempted isolation of virus from faeces for up to 35 days after infection; occasionally rectal swabs were used to obtain fresh samples. The medium was changed after 24 hours and 4 days later any viral eytopathic effect was recorded, the medium was removed and passaged in fresh APT/2 cultures and the eoverslips were stained to demonstrate virM antigen by indirect immunofluorescence, using paired sera from a gnotobiotic piglet before and after TGEV infection, followed by FITCconjugated rabbit anti-swine globulin (Nordic Immunological Laboratories, London).

title:
  Virus isolation and serum antibody responses after infection of cats with transmissible gastroenteritis virus

abstract:
  Transmissible gastroenteritis virus was administered orally to cats. No clinical disease resulted but infectious virus was isolated from faeces for up to 22 days after infection and serum antibody was detected by neutralisation and immunofluorescence tests.


id: cord-004755-rmnjs1t6
author: Welch, Siao-Kun Wan
date: 1988
txt: ./txt/cord-004755-rmnjs1t6.txt
cache: ./cache/cord-004755-rmnjs1t6.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7086875/
doi: 10.1007/bf01311003
summary:
  Twelve hybridomas secreting monoclonal antibodies (MAbs) against Miller virulent strain of transmissible gastroenteritis virus (TGEV) were generated and characterized. Two E 2-specific MAbs had higher neutralizing antibody titers (782 to 34,117) and showed 4-to 13-fold differences in titers against the attenuated and virulent TGEV strains. Two E 2-specific MAbs had higher neutralizing antibody titers (782 to 34,117) and showed 4-to 13-fold differences in titers against the attenuated and virulent TGEV strains. In two previous studies, monoclonal antibodies (MAbs) to the structural proteins of the attenuated (Purdue) strain of TGEV were described [9, 12] . These MAbs were further characterized in various comparative assays including cell culture immunofluorescence, virus neutralization, and radioimmunoprecipitation for reactivity against the Miller virulent and Purdue attenuated strains of TGEV. Anti-E 1 MAbs prepared against a mixture of virulent Miller 3 and Purdue attenuated strains of TGEV had virus neutralizing antibody titers only in the presence of guinea pig, rabbit or swine complement [22] .

title:
  Monoclonal antibodies to a virulent strain of transmissible gastroenteritis virus: comparison of reactivity with virulent and attenuated virus

abstract:
  Twelve hybridomas secreting monoclonal antibodies (MAbs) against Miller virulent strain of transmissible gastroenteritis virus (TGEV) were generated and characterized. In a cell culture immunofluorescence (CCIF) assay, three MAbs directed against peplomer protein (E 2) had perinuclear fluorescence and four unclassified MAbs showed cell membrane fluorescence. Six of these seven MAbs neutralized both attenuated and virulent TGEV, and the seventh (an unclassified MAb) neutralized only the latter virus. Two MAbs able to bind the cell membrane of infected cells had low neutralizing antibody titers (8 to 72) but were able to distinguish between virulent and attenuated TGEV (9- to 72-fold differences in neutralizing titers). Two E 2-specific MAbs had higher neutralizing antibody titers (782 to 34,117) and showed 4- to 13-fold differences in titers against the attenuated and virulent TGEV strains. Five MAbs which were specific for nucleocapsid (N) protein had cytoplasmic, particulate fluorescence in CCIF, and did not neutralize TGEV. Comparison of CCIF antibody titers of MAbs to the virulent and attenuated strains of TGEV indicated that differences existed in titers of most E 2 and all N-specific MAbs, with titers consistently higher against virulent TGEV (homologous strain). Hyperimmune antisera prepared in gnotobiotic pigs against the attenuated, virulent and a recent isolate of TGEV immunoprecipitated the 3 major structural proteins of both the attenuated and virulent TGEV strains. Relative mol. wt. differences in the E 1 and E 2 proteins between the two virus strains were revealed using either the hyperimmune pig sera or MAbs. In addition to the 48 K N protein, a 44 K protein was coimmunoprecipitated by the hyperimmune sera and MAbs, but mainly from lysates of attenuated TGEV.


id: cord-007461-v3tff2gk
author: Nguyen, T.D.
date: 2002-11-12
txt: ./txt/cord-007461-v3tff2gk.txt
cache: ./cache/cord-007461-v3tff2gk.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7117195/
doi: 10.1016/0378-1135(87)90026-5
summary:
  Four transmissible gastroenteritis virus (TGEV) strains (Purdue-115, D-52, 188-SG and Gep-II) and two cell lines (swine testis-ST and pig kidney-RPD) were used to study virus attachment and cell susceptibility. A field TGEV strain (Gep-II), which was unable to multiply in cell cultures, appeared able to inhibit the attachment of radiolabelled cell-passaged virus. The effect of these chemicals on virus attachment was tested by using the plaque assay as described above, except that the inoculum containing 50-100 P.F.U. was prepared in the presence of the chemical at appropriate concentrations and incubated with confluent monolayer cells for 30 min at 37 ° C. Differences in susceptibility to TGEV infection, indicated by plaque formation, between the ST and RPD cells and effects of temperature on virus attachment were studied by incubating virus inoculum with the cells for 30 min at either 4 or 37°C.

title:
  Transmissible gastroenteritis (TGE) of swine: In vitro virus attachment and effects of polyanions and polycations

abstract:
  Four transmissible gastroenteritis virus (TGEV) strains (Purdue-115, D-52, 188-SG and Gep-II) and two cell lines (swine testis-ST and pig kidney-RPD) were used to study virus attachment and cell susceptibility. Virus attachment was partially thermodependent and the rate varied, depending on the strain. Identical TGEV inocula produced a higher plaque number by plaque assay in the swine testis cell line (ST) than in the pig kidney cell line (RPD) but [(3)H]uridine-labèlled virus was found associated equally well with both cell lines. A field TGEV strain (Gep-II), which was unable to multiply in cell cultures, appeared able to inhibit the attachment of radiolabelled cell-passaged virus. Therefore, the susceptibility to TGEV infection was apparently not determined at the virus-to-cell attachment stage. The attachment sites on the cell surface were specific, however, differences in TGEV attachment determinant between strains were not observed. Attachment of all the virus strains tested was enhanced by DEAE-dextran and inhibited by dextran sulfate, poly-L-lysine (PLL), poly-L-α-ornithine (PLO) and protamine sulfate.


id: cord-007491-yxz69nil
author: Weingartl, H.M.
date: 2002-11-13
txt: ./txt/cord-007491-yxz69nil.txt
cache: ./cache/cord-007491-yxz69nil.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7117419/
doi: 10.1016/0378-1135(93)90113-l
summary:
  Binding of the low cell culture passaged Miller-6 strain of transmissible gastroenteritis virus (TGEV) to villous enterocytes from newborn piglets was at a high level, similar to that observed to culturedswine test is (ST) cells. In this paper we describe the binding of TGEV to susceptible porcine and resistant bovine cell cultures, and to enterocytes contained in a series of fractions collected from the tips of the villi to the crypts of the jejunum of neonatal and weaned piglets. Of the enterocyte fractions harvested from the tips of the villi or the crypts of a newborn or a weaned piglet, and tested in the competitive virus binding assay, only the enterocytes harvested from the villi of the newborn piglet showed saturable binding of TGEV (Fig. 4 ) , similar to that demonstrated for ST cells.

title:
  Binding of porcine transmissible gastroenteritis virus by enterocytes from newborn and weaned piglets

abstract:
  Enterocytes were harvested by chelation in a series of seven fractions from the tips of the villi to the crypts of the jejunum of newborn or weaned piglets. Binding of the low cell culture passaged Miller-6 strain of transmissible gastroenteritis virus (TGEV) to villous enterocytes from newborn piglets was at a high level, similar to that observed to culturedswine test is (ST) cells. Binding of the virus to cryptal enterocytes from newborn piglets or to villous or cryptal enterocytes from weaned piglets was significantly lower. In a competitive virus binding assay with radiolabelled virus, the binding of TGEV to ST cells was found to be saturable, while binding to MDBK cells, in which the virus fails to replicate, was at a lower level and was non-saturable. In the same assay, virus binding to the villous enterocytes from the jejunum of a newborn piglet was saturable, while binding to cryptal enterocytes from a newborn piglet, and to villous and cryptal enterocytes from a weaned piglet, was non-saturable. It was concluded that the high susceptibility of newborn piglets to TGEV infection, and the tropism of the virus for villous enterocytes, may relate to the presence of specific, saturable binding sites on the plasma membrane of villous enterocytes.


id: cord-010045-eqzs01au
author: Britton, P.
date: 2006-10-27
txt: ./txt/cord-010045-eqzs01au.txt
cache: ./cache/cord-010045-eqzs01au.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7168467/
doi: 10.1111/j.1365-2958.1988.tb00010.x
summary:
  Yeast cells containing recombinant plasmids, with the nucleoprotein gene in the correct orientation, produced a polypeptide of M, 47000, identical to the viral product, that reacted with a specific monoclonal antibody. Three recombinant plasmids, shown to contain cDNA inserts of 1.5 kbp and designated pTS13-2, pTS15-1 and pTSi 5-2, were labelled with p^S]-dATP by nick translation and hybridized to glyoxylated TGEV mRNA species separated on 1 % agarose gels as described in Experimentat procedures. The plasmid also contained the smaller 3'' ORF which initiates, in a different reading frame, 6 bp 3'' from the end of the nucleoprotein gene and terminates 166 bp 5'' to the Drall Sma\ combined site between the TGEV cDNA insert and the pUC9 DNA. A recombinant plasmid, pYNGI, was found to contain the TGEV nucleoprotein gene in the correct orientation for expression under the control of the yeast GAL1 promoter.

title:
  Sequence of the nucleoprotein gene from a virulent British field isolate of transmissible gastroenteritis virus and its expression in Saccharomyces cerevisiae

abstract:
  Subgenomic mRNA from a virulent isolate of porcine transmissible gastroenteritis virus (TGEV) was used to produce cDNA which was sequenced. Two non‐overlapping open reading frames (ORFs) were identified. The largest, encoding a polypeptide of 382 amino acids (relative molecular mass (M(r)) 43 483), was shown to be the viral nucleoprotein gene. The second ORF, found 3’to the larger ORF, encodes a polypeptide of 78 amino acids (M(r) 9068) which has yet to be assigned to a viral product. The nucleoprotein gene was expressed in yeast cells under the control of two types of yeast promoters: the constitutive PGK promoter, and the inducible GAL1 promoter. Yeast cells containing recombinant plasmids, with the nucleoprotein gene in the correct orientation, produced a polypeptide of M, 47000, identical to the viral product, that reacted with a specific monoclonal antibody.


id: cord-014697-aea67d8f
title: Immunogenicity of a recombinant coronavirus spike glycoprotein expressed in transgenic plants
author: Escribano, J.M.
date: 2000
txt: ./txt/cord-014697-aea67d8f.txt
cache: ./cache/cord-014697-aea67d8f.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7082855/
doi: 10.1007/s001030050020
summary:
  Recently, it has been demonstrated that plants offer the possibility of producing low cost subunit vaccines that can be either parenterally or orally administered.Here we review data we obtained on the immunological response elicited by two recombinant versions of the glycoprotein S from the swine transmissible gastroenteritis coronavirus (TGEV) expressed in transgenic plants.Arabidopsis or potato plants were genetically transformed with cDNAs constructs encoding the N-terminal domain (aa residues 1-750) or the full-length glycoprotein S of TGEV, responsible for the neutralizing antibody induction against the virus, under the control of the cauliflower mosaic virus 35S (CaMV 35S) promoter.Genomic DNA and mRNA analysis of leave extracts from transformed plants demonstrated the incorporation of the foreign cDNA into the plant genomes as well as their transcription.Expression of recombinant polypeptides was observed in most transgenic plants by ELISA using specific antibodies.Mice immunized either parenterally with leave extracts from transgenic arabidopsis plants or, more interestingly, fed with potato tubers, developed antibodies that specifically reacted with TGEV in ELISA, immunoprecipitated the glycoprotein S and in some cases neutralized the virus infectivity.From the above results, we conclude that transgenic plants expressing glycoprotein S polypeptides may be potentially used as a source of recombinant antigen for vaccine production.

abstract:
  Recently, it has been demonstrated that plants offer the possibility of producing low cost subunit vaccines that can be either parenterally or orally administered. Here we review data we obtained on the immunological response elicited by two recombinant versions of the glycoprotein S from the swine transmissible gastroenteritis coronavirus (TGEV) expressed in transgenic plants. Arabidopsis or potato plants were genetically transformed with cDNAs constructs encoding the N-terminal domain (aa residues 1–750) or the full-length glycoprotein S of TGEV, responsible for the neutralizing antibody induction against the virus, under the control of the cauliflower mosaic virus 35S (CaMV 35S) promoter. Genomic DNA and mRNA analysis of leave extracts from transformed plants demonstrated the incorporation of the foreign cDNA into the plant genomes as well as their transcription. Expression of recombinant polypeptides was observed in most transgenic plants by ELISA using specific antibodies. Mice immunized either parenterally with leave extracts from transgenic arabidopsis plants or, more interestingly, fed with potato tubers, developed antibodies that specifically reacted with TGEV in ELISA, immunoprecipitated the glycoprotein S and in some cases neutralized the virus infectivity. From the above results, we conclude that transgenic plants expressing glycoprotein S polypeptides may be potentially used as a source of recombinant antigen for vaccine production.


id: cord-015742-nt44jcjm
title: Antigenicity of structural components from porcine transmissible gastroenteritis virus
author: Garwes, D.J.
date: 2002-11-13
txt: ./txt/cord-015742-nt44jcjm.txt
cache: ./cache/cord-015742-nt44jcjm.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7117557/
doi: 10.1016/0378-1135(79)90034-8
summary:
  Incubation of 3H-uridine TGEV with sera from sows inoculated with viral antigen resulted in the formation of immune complexes that were retained by membrane filters (Fig. 2) . Sera from sows inoculated with whole virus, SP antigen or SVP antigen preparations produced virus complexes that were retained most efficient Samples of 3H-uridine labelled TGEV containing 4000 ct/min were incubated for 2 h at 37°C in dilutions of test sera followed by incubation with rabbit anti-porcine IgG serum. Analysis of the immunoglobulin classes responsible for neutralising activity after inoculation of sows by the intramammary route showed that IgG was the predominant antibody species in both serum and colostrum, consistent with previous findings with inactivated TGEV Lucas et al., 1974) but differing from the stimulation of IgA to ferritin reported by Bourne et al. 9, which received SP antigen, produced neutralising antibody of the IgA class in the colostrum and was the only animal capable of protecting her piglets against challenge with live virus.

abstract:
  Pregnant sows were inoculated with inactivated transmissible gastroenteritis virus and with preparations of virus surface projections and subviral particles derived by detergent treatment of the virus. Neutralising antibody was demonstrated in serum and colostrum from animals that received whole virus or preparations of surface projections whereas subviral particles failed to stimulate neutralising antibody formation. Similar results were obtained with serum from rabbits inoculated with whole virus and structural components. All three preparations stimulated the formation of agglutinating antibodies, as demonstrated by sedimentation analysis and filtration studies with radiolabelled virus. The immunoglobulin classes responsible for neutralising antibody activity in sows inoculated by the intramammary route were examined. In each case where the immunoglobulin class was determined, IgG was found. One sow that received surface projections also had IgA with neutralising activity in her colostrum. In contrast, infection of sows with live whole virus resulted in neutralising antibody of the IgG, IgM and IgA classes.


id: cord-016178-2ix6c0he
title: An Oral Vaccine for TGEV Immunization of Pigs
author: Rajan, V.
date: 2014-05-28
txt: ./txt/cord-016178-2ix6c0he.txt
cache: ./cache/cord-016178-2ix6c0he.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7120389/
doi: 10.1007/978-3-662-43836-7_8
summary:
  These efforts towards the expression of the S-antigen of TGEV in maize seed, its effectiveness at inducing neutralizing antibody production in the colostrum of gilts, and its efficacy in protecting piglets against challenge by virulent TGEV are summarized here. Potentially, the methods to protect naïve piglets at highest risk from TGEV infection are to provide immune colostrum by vaccinating sows and an oral/nasal vaccine to boost secretory neutralizing antibody levels. The induction of neutralizing antibodies in both serum and colostrum was examined in gilts following the administration of oral TGEV vaccine in maize comprising a subunit vaccine of the S-protein expressed in corn (Lamphear et al. Administration of antigen over a 4-day period gave the highest levels of protection against live challengeeven higher than oral vaccination with a modified live virus (Fig. 8.4 ; see Sect. Protection with a subunit antigen expressed in corn, exclusively by the oral route, is shown for the first time to be effective in piglets, the target species for immunization.

abstract:
  Transmissible gastroenteritis virus (TGEV) is a commercially important pathogen of hog farms and causes contagious, lethal diarrhea in piglets. While orally and parenterally administered vaccines made from inactivated or attenuated TGEV are commercially available, they require individual administration to piglets, which is time and labor intensive, and run the risk of reversion to pathogenicity. Also, parenteral vaccines produce neutralizing serum antibodies which may be less effective against an orally transmitted pathogen, compared to an oral vaccine that would induce the production of mucosal antibodies. There has been an effort to produce subunit vaccines in an edible form in plants for convenient administration through feed. These efforts towards the expression of the S-antigen of TGEV in maize seed, its effectiveness at inducing neutralizing antibody production in the colostrum of gilts, and its efficacy in protecting piglets against challenge by virulent TGEV are summarized here.


id: cord-018078-clxzp1ph
title: Coronavirus infections in veterinary medicine
author: Weber, Olaf
date: 2005
txt: ./txt/cord-018078-clxzp1ph.txt
cache: ./cache/cord-018078-clxzp1ph.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7122866/
doi: 10.1007/3-7643-7339-3_2
abstract: nan
summary:
  Some important viruses that are discussed below belong to group I and include the canine enteric coronavirus (CECoV), the transmissible gastroenteritis virus (TGEV) of swine, the porcine epidemic diarrhoea virus (PEDV), the porcine respiratory coronavirus (PRCoV) and the feline coronaviruses (FCoVs). The clinical symptoms of endemic/enzootic TGE are usually less severe in the older pigs, making a clinical differentiation between TGE and other infectious enteric diseases, like that caused by rotaviruses and/or clostridia, impossible. Bovine coronavirus (BCoV) is an important cause of neonatal calf diarrhea [33] but may also infect the respiratory tract and has been recognized as the causing agent especially for winter dysentery in adult cattle. As for other coronaviruses, seasonal changes in temperature, environmental factors but also the immune status play an important role in the transmission of the virus and the clinical outcome of the infection. Two amino acid changes at the N-terminus of transmissible gastroenteritis coronavirus spike protein result in the loss of enteric tropism


id: cord-018865-melttpiq
author: Yu, Tian-fei
date: 2012
txt: ./txt/cord-018865-melttpiq.txt
cache: ./cache/cord-018865-melttpiq.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7123857/
doi: 10.1007/978-3-642-27537-1_7
summary:
  In order to illuminate the antigenicity of porcine transmissible gastroenteritis virus (TGEV) spike protein B and C antigen sites, the truncated spike gene including B and C antigen sites of Chinese isolate TH-98 was expressed respectively in E.coli, baculovirus and pichia pastoris expression systems. Dot-ELISA assays based on these three recombinant proteins were developed to detect TGEV antibodies and could avoid antibody cross-reaction from PRCV theoretically. The recombinant B and C antigen sites protein expressed into the yeast culture supernatant was identified on the bases of its molecular weight. When the amount of spotting is 50ng, the recombinant B and C antigen sites protein expressed into the yeast culture supernatant show the positive reaction in contrast with the GS115 cells transformed with pPIC9K plasmids (Fig. 2. Antigenic variation among transmissible gastroenteritis virus (TGEV) and porcine respiratory coronavirus strains detected with monoclonal antibodies to the S protein of TGEV

title:
  Express Transmissible Gastroenteritis Virus Spike Gene B and C Antigen Sites in Multiple Expression Systems

abstract:
  In order to illuminate the antigenicity of porcine transmissible gastroenteritis virus (TGEV) spike protein B and C antigen sites, the truncated spike gene including B and C antigen sites of Chinese isolate TH-98 was expressed respectively in E.coli, baculovirus and pichia pastoris expression systems. Dot enzyme-linked immunosorbent assays (Dot-ELISA) based on these three recombinant proteins were developed preliminarily. Ten sera obtained correspondingly from ten piglets two months old which showed up clinical symptom were used for examination. The study indicates that the assays are rapid, reliable and sensitive and it has the potential for use as serological methods for TGEV diagnosis.


id: cord-023855-3ta5lhnw
title: Alphacoronavirus(‡): Coronaviridae
author: Decaro, Nicola
date: 2011
txt: ./txt/cord-023855-3ta5lhnw.txt
cache: ./cache/cord-023855-3ta5lhnw.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7176201/
doi: 10.1007/978-0-387-95919-1_56
abstract: nan
summary:
  Year of event Event References Transmissible gastroenteritis virus (TGEV) associated with enteritis in swine Doyle and Hutchings (1946) 1965 Coronaviruses associated with common colds in humans Tyrrell and Bynoe (1965) 1975 Radiolabeling (TGEV) clarifies fundamental coronavirus protein composition (S, N, M proteins) Garwes and Pocock (1975) 1975 ICTV approves Coronaviridae family with one genus, Coronavirus Tyrrell et al (1975 Tyrrell et al ( ) 1980 Demonstration that antibodies to feline enteric coronavirus enhance feline infectious peritonitis Pedersen and Boyle (1980) 1989 Alternative model for transcription (TGEV): discontinuous transcription during negative strand synthesis Sethna et al (1989 Sethna et al ( ) 1982 Amino peptidase N receptor for TGEV and HCoV-229E Delmas et al (1992) 1996 ICTV recognises Coronaviridae as containing 2 genera: Coronavirus and Torovirus Cavanagh et al (1997) Year of event Event References 1996 ICTV recognises the order Nidovirales containing families Coronaviridae and Arteriviridae Cavanagh et al (1997 Cavanagh et al ( ) 1999 Recombinant TGEV shows that S protein determines enteropathogenicity and virulence Sanchez et al (1999) Coronaviridae: the viruses and their replication The coronaviridae.


id: cord-253041-ts2aiykg
author: Ding, Li
date: 2014-03-07
txt: ./txt/cord-253041-ts2aiykg.txt
cache: ./cache/cord-253041-ts2aiykg.txt
extension: .txt
mime: text/plain
url: https://www.sciencedirect.com/science/article/pii/S0006291X14002915
doi: 10.1016/j.bbrc.2014.02.039
summary:
  Moreover, the expression of TGEV N gene promoted translocation of Bax to mitochondria, which in turn caused the release of cytochrome c, followed by activation of caspase-3, resulting in cell apoptosis in the transfected PK-15 cells following cell cycle arrest. Further studies showed that p53 inhibitor attenuated TGEV N protein induced cell cycle arrest at S and G2/M phases and apoptosis through reversing the expression changes of cdc2, cdk2 and cyclin B1 and the translocation changes of Bax and cytochrome c induced by TGEV N protein. Taken together, these results demonstrated that TGEV N protein might play an important role in TGEV infection-induced p53 activation and cell cycle arrest at the S and G2/M phases and apoptosis occurrence. In the present study, we demonstrate that TGEV N protein, when expressed within cells, can cause cell cycle arrest and apoptosis in PK-15 cells, in which p53 and p21 activation, cyclin B1 and cdc2 decrease, Bax translocation to mitochondria, cytochrome c release and subsequent activation of caspase-3 are required.

title:
  TGEV nucleocapsid protein induces cell cycle arrest and apoptosis through activation of p53 signaling

abstract:
  Abstract Our previous studies showed that TGEV infection could induce cell cycle arrest and apoptosis via activation of p53 signaling in cultured host cells. However, it is unclear which viral gene causes these effects. In this study, we investigated the effects of TGEV nucleocapsid (N) protein on PK-15 cells. We found that TGEV N protein suppressed cell proliferation by causing cell cycle arrest at the S and G2/M phases and apoptosis. Characterization of various cellular proteins that are involved in regulating cell cycle progression demonstrated that the expression of N gene resulted in an accumulation of p53 and p21, which suppressed cyclin B1, cdc2 and cdk2 expression. Moreover, the expression of TGEV N gene promoted translocation of Bax to mitochondria, which in turn caused the release of cytochrome c, followed by activation of caspase-3, resulting in cell apoptosis in the transfected PK-15 cells following cell cycle arrest. Further studies showed that p53 inhibitor attenuated TGEV N protein induced cell cycle arrest at S and G2/M phases and apoptosis through reversing the expression changes of cdc2, cdk2 and cyclin B1 and the translocation changes of Bax and cytochrome c induced by TGEV N protein. Taken together, these results demonstrated that TGEV N protein might play an important role in TGEV infection-induced p53 activation and cell cycle arrest at the S and G2/M phases and apoptosis occurrence.


id: cord-254735-8reu45yz
author: Reguera, Juan
date: 2012-08-02
txt: ./txt/cord-254735-8reu45yz.txt
cache: ./cache/cord-254735-8reu45yz.txt
extension: .txt
mime: text/plain
url: https://doi.org/10.1371/journal.ppat.1002859
doi: 10.1371/journal.ppat.1002859
summary:
  Here we describe the crystal structures of the receptor-binding domains (RBDs) of two closely related CoV strains, transmissible gastroenteritis virus (TGEV) and porcine respiratory CoV (PRCV), in complex with their receptor, porcine APN (pAPN), or with a neutralizing antibody. The report uncovers a unique virus-receptor recognition mode that engages a glycan N-linked to the pAPN ectodomain, revealing structural determinants of the receptor-binding specificity in CoVs. Neutralizing antibodies target viral residues used for binding to the APN receptor and entry into host cells, showing that efficient CoV neutralization requires immune responses focused toward key receptor binding motifs in the virus envelope. The RBD tip, shown here as the pAPN-binding edge of the domain (Figure 3) , is the main S protein determinant of antigenic site A, recognized by the most effective neutralizing antibodies of TGEV and related CoV infections [25, 26] .

title:
  Structural Bases of Coronavirus Attachment to Host Aminopeptidase N and Its Inhibition by Neutralizing Antibodies

abstract:
  The coronaviruses (CoVs) are enveloped viruses of animals and humans associated mostly with enteric and respiratory diseases, such as the severe acute respiratory syndrome and 10–20% of all common colds. A subset of CoVs uses the cell surface aminopeptidase N (APN), a membrane-bound metalloprotease, as a cell entry receptor. In these viruses, the envelope spike glycoprotein (S) mediates the attachment of the virus particles to APN and subsequent cell entry, which can be blocked by neutralizing antibodies. Here we describe the crystal structures of the receptor-binding domains (RBDs) of two closely related CoV strains, transmissible gastroenteritis virus (TGEV) and porcine respiratory CoV (PRCV), in complex with their receptor, porcine APN (pAPN), or with a neutralizing antibody. The data provide detailed information on the architecture of the dimeric pAPN ectodomain and its interaction with the CoV S. We show that a protruding receptor-binding edge in the S determines virus-binding specificity for recessed glycan-containing surfaces in the membrane-distal region of the pAPN ectodomain. Comparison of the RBDs of TGEV and PRCV to those of other related CoVs, suggests that the conformation of the S receptor-binding region determines cell entry receptor specificity. Moreover, the receptor-binding edge is a major antigenic determinant in the TGEV envelope S that is targeted by neutralizing antibodies. Our results provide a compelling view on CoV cell entry and immune neutralization, and may aid the design of antivirals or CoV vaccines. APN is also considered a target for cancer therapy and its structure, reported here, could facilitate the development of anti-cancer drugs.


id: cord-255238-adpn5fb9
title: Discovery of a novel swine enteric alphacoronavirus (SeACoV) in southern China
author: Pan, Yongfei
date: 2017-09-28
txt: ./txt/cord-255238-adpn5fb9.txt
cache: ./cache/cord-255238-adpn5fb9.txt
extension: .txt
mime: text/plain
url: https://doi.org/10.1016/j.vetmic.2017.09.020
doi: 10.1016/j.vetmic.2017.09.020
summary:
  Isolation and propagation of the pathogen in cell culture resulted in discovery of a novel swine enteric alphacoronavirus (tentatively named SeACoV) related to the bat coronavirus HKU2 identified in the same region a decade ago. Most recently, several chimeric SeCoV strains with a TGEV genomic backbone replaced by a PEDV spike (S) gene were identified from swine fecal samples in Europe (Akimkin et al., 2016; Belsham et al., 2016; Boniotti et al., 2016) , implying that novel SeCoV pathogens could emerge by inter-CoV recombination under co-infection. In this study, we report the isolation and genetic characterization of a novel swine enteric alphacoronavirus (tentatively named SeACoV), related to a bat enteric coronavirus, from a pig farm that reported newborn-piglet diarrhea in southern China in 2017.

abstract:
  Outbreaks of diarrhea in newborn piglets without detection of transmissible gastroenteritis virus (TGEV), porcine epidemic diarrhea virus (PEDV) and porcine deltacoronavirus (PDCoV), have been recorded in a pig farm in southern China since February 2017. Isolation and propagation of the pathogen in cell culture resulted in discovery of a novel swine enteric alphacoronavirus (tentatively named SeACoV) related to the bat coronavirus HKU2 identified in the same region a decade ago. Specific fluorescence signal was detected in Vero cells infected with SeACoV by using a positive sow serum collected in the same farm, but not by using TGEV-, PEDV- or PDCoV-specific antibody. Electron microscopy observation demonstrated that the virus particle with surface projections was 100–120 nm in diameter. Complete genomic sequencing and analyses of SeACoV indicated that the extreme amino-terminal domain of the SeACoV spike (S) glycoprotein structurally similar to the domain 0 of the alphacoronavirus NL63, whereas the rest part of S structurally resembles domains B to D of the betacoronavirus. The SeACoV-S domain 0 associated with enteric tropism had an extremely high variability, harboring 75-amino-acid (aa) substitutions and a 2-aa insertion, compared to that of HKU2, which is likely responsible for the extended host range or cross-species transmission. The isolated virus was infectious in pigs when inoculated orally into 3-day-old newborn piglets, leading to clinical signs of diarrhea and fecal virus shedding. These results confirmed that it is a novel swine enteric coronavirus representing the fifth porcine coronavirus.


id: cord-255653-0bj5eh5d
author: Pensaert, M. B.
date: 1981
txt: ./txt/cord-255653-0bj5eh5d.txt
cache: ./cache/cord-255653-0bj5eh5d.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/6166280/
doi: 10.1007/bf01315166
summary:
  A possible antigenic relationship between the porcine enteropathogenic coronavirus-like agent (CVLA) and 6 known coronaviruses was examined by immunoelectron microscopy (IEM) and by immunofluorescence (IF). CVLA did not show cross reactivity with infectious bronchitis virus, transmissible gastroenteritis virus (TGEV), canine coronavirus (CCV) hemagglutinating encephalomyelitis virus (HEV), neonatal calf diarrhea coronavirus (NCDCV) or feline infectious peritonitis virus (FIPV). The CVLA was shown by serologic cross protection studies to differ from the two knowm porcine coronaviruses, transmissible gastroenteritis virus (TGEV) and hemagglntinating encephalomyelitis virus (HEV) (4, 14) . The coronaviruses selected for the present study were TGEV, HEV, neonatal calf diarrhea coronavirus (NCDCV), canine coronavirus (CCV), avian infectious bronchitis virus (IBV) and feline infectious peritonitis virus (FIPV). This hyperimmune serum had a virus neutralizing titer of 1:2560 when tested against the cell culture adapted Purdue strain of TGEV. Antiserum to TGEV reacted with CCV, but did not show detectable antigenic cross-reactivity with FIPV.

title:
  An immunoelectron microscopic and immunofluorescent study on the antigenic relationship between the coronavirus-like agent, CV 777, and several coronaviruses

abstract:
  A possible antigenic relationship between the porcine enteropathogenic coronavirus-like agent (CVLA) and 6 known coronaviruses was examined by immunoelectron microscopy (IEM) and by immunofluorescence (IF). CVLA did not show cross reactivity with infectious bronchitis virus, transmissible gastroenteritis virus (TGEV), canine coronavirus (CCV) hemagglutinating encephalomyelitis virus (HEV), neonatal calf diarrhea coronavirus (NCDCV) or feline infectious peritonitis virus (FIPV). Antigenic relationship was detected by IEM between TGEV and CCV, NCDCV and HEV and by IF between TGEV and CCV, TGEV and FIPV, HEV and NCDCV.


id: cord-256316-1odgm6hm
title: TGEV corona virus ORF4 encodes a membrane protein that is incorporated into virions
author: Godet, Murielle
date: 1992-06-30
txt: ./txt/cord-256316-1odgm6hm.txt
cache: ./cache/cord-256316-1odgm6hm.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/1316677/
doi: 10.1016/0042-6822(92)90521-p
summary:
  Several lines of evidence lend support to the view that a gene encoding an SM-like protein is a common feature of the coronavirus genomes: (i) an ORF predicting a polypeptide with striking similarities to TGEV ORF4 was identified in the genome sequence of each of the 5 coronaviruses examined (Fig. 9 ) and the fact that TGEV SM was recognized by anti-FIPV antibodies argues for the presence of a related gene also in feline infectious peritonitis virus genome; (ii) the product expressed from the relevant MHV, BCV, and IBV ORFs was reported to have properties of a transmembrane polypeptide (Leibowitz et a/., 1988; Smith et al., 1990; Abraham et a/., 1990) ; and (iii) although expressed through a mono-, di-, or tricistronic mRNA (Abraham et a/., 1990; Budzilowicz and Weiss, 1987; Liu et al., 1991 ) the assumed SM-encoding genes are all located upstream and adjacent to the M protein gene.

abstract:
  Abstract The coding potential of the open reading frame ORF4 (82 amino acids) of transmissible gastroenteritis virus (TGEV) has been confirmed by expression using a baculovirus vector. Five monoclonal antibodies (MAbs) raised against the 10K recombinant product immunoprecipitated a polypeptide of a similar size in TGEV-infected cells. Immunofluorescence assays performed both on insect and mammalian cells revealed that ORF4 was a membrane-associated protein, a finding consistent with the prediction of a membrane-spanning segment in ORF4 sequence. Two epitopes were localized within the last 21 C-terminal residues of the sequence through peptide scanning and analysis of the reactivity of a truncated ORF4 recombinant protein. Since the relevant MAbs were found to induce a cell surface fluorescence, these data suggest that ORF4 may be an integral membrane protein having a Cexo-Nendo orientation. Anti-ORF4 MAbs were also used to show that ORF4 polypeptide may be detected in TGEV virion preparations, with an estimated number of 20 molecules incorporated per particle. Comparison of amino acid sequence data provided strong evidence that other coronaviruses encode a polypeptide homologous to TGEV ORF4. Our results led us to propose that ORF4 represents a novel minor structural polypeptide, tentatively designated SM (small membrane protein).


id: cord-256444-grw5s2pf
title: The Molecular Biology of Coronaviruses
author: Lai, Michael M.C.
date: 1997-12-31
url: https://api.elsevier.com/content/article/pii/S0065352708602869
doi: 10.1016/s0065-3527(08)60286-9
abstract:
  Publisher Summary This chapter discusses the manipulation of clones of coronavirus and of complementary DNAs (cDNAs) of defective-interfering (DI) RNAs to study coronavirus RNA replication, transcription, recombination, processing and transport of proteins, virion assembly, identification of cell receptors for coronaviruses, and processing of the polymerase. The nature of the coronavirus genome is nonsegmented, single-stranded, and positive-sense RNA. Its size ranges from 27 to 32 kb, which is significantly larger when compared with other RNA viruses. The gene encoding the large surface glycoprotein is up to 4.4 kb, encoding an imposing trimeric, highly glycosylated protein. This soars some 20 nm above the virion envelope, giving the virus the appearance-with a little imagination-of a crown or coronet. Coronavirus research has contributed to the understanding of many aspects of molecular biology in general, such as the mechanism of RNA synthesis, translational control, and protein transport and processing. It remains a treasure capable of generating unexpected insights.


id: cord-257116-6td3efjw
author: Zhou, Yanrong
date: 2017-08-09
txt: ./txt/cord-257116-6td3efjw.txt
cache: ./cache/cord-257116-6td3efjw.txt
extension: .txt
mime: text/plain
url: https://doi.org/10.3389/fimmu.2017.00940
doi: 10.3389/fimmu.2017.00940
summary:
  title: Cellular RNA Helicase DDX1 Is Involved in Transmissible Gastroenteritis Virus nsp14-Induced Interferon-Beta Production In summary, our data revealed a potential coactivator role of host RNA helicase DDX1 to the induction of IFN-β response initiated by TGEV and demonstrated that nsp14 is an important IFN inducer among the TGEV-encoded proteins. In this study, we found that TGEV infection significantly facilitated IFN-β production as well as activation of the transcription factors IFN regulatory factor 3 (IRF3) and nuclear factor-kappaB (NF-κB) in porcine kidney (PK-15) cells. In summary, our data revealed a potential coactivator role of host RNA helicase DDX1 to the induction of IFN-β response initiated by TGEV and demonstrated that nsp14 is an important IFN inducer among the TGEVencoded proteins. Nsp14 interacts with cellular DExD/H helicase DDX1 to activate IFN-β in a NF-κB dependent manner, and DDX1 is associated with TGEV-induced IFN-β production, revealing a potential coactivator role of host RNA helicase DDX1 on virus and viral protein induced innate immune responses.

title:
  Cellular RNA Helicase DDX1 Is Involved in Transmissible Gastroenteritis Virus nsp14-Induced Interferon-Beta Production

abstract:
  Transmissible gastroenteritis virus (TGEV), an enteropathogenic coronavirus (CoV) of porcine, causes lethal watery diarrhea and severe dehydration in piglets and leads to severe economic losses in the swine industry. Unlike most CoVs that antagonize type I interferon (IFN) production, previous studies showed that TGEV infection induces IFN-I production both in vivo and in vitro. However, the underlying mechanism(s) remain largely unknown. In this study, we found that TGEV infection significantly facilitated IFN-β production as well as activation of the transcription factors IFN regulatory factor 3 (IRF3) and nuclear factor-kappaB (NF-κB) in porcine kidney (PK-15) cells. Screening of TGEV-encoded proteins demonstrated that non-structural protein 14 (nsp14) was the most potent IFN-β inducer and induced IFN-β production mainly by activating NF-κB but not IRF3. Further analysis showed that nsp14 interacted with DDX1, a member of the DExD/H helicase family. Knockdown of DDX1 by specific small interfering RNA (siRNA) significantly decreased nsp14-induced IFN-β production and NF-κB activation. Furthermore, TGEV-induced IFN-β production and IFN-stimulated gene (ISG) expression were decreased in cells transfected with DDX1-specific siRNA, indicating the vital role of DDX1 to TGEV-induced IFN-β responses. In summary, our data revealed a potential coactivator role of host RNA helicase DDX1 to the induction of IFN-β response initiated by TGEV and demonstrated that nsp14 is an important IFN inducer among the TGEV-encoded proteins.


id: cord-257136-zpeh8pmc
author: Huang, Xin
date: 2019-04-26
txt: ./txt/cord-257136-zpeh8pmc.txt
cache: ./cache/cord-257136-zpeh8pmc.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/31025076/
doi: 10.1007/s00253-019-09835-7
summary:
  To develop a simple, rapid, accurate, and high-throughput detection method for diagnosis and differential diagnosis on swine enteric coronaviruses, specific primers and probes were designed based on the highly conserved regions of transmissible gastroenteritis virus (TGEV) N, porcine epidemic diarrhea virus (PEDV) M, porcine deltacoronavirus (PDCoV) M, and porcine enteric alphacoronavirus (PEAV) N genes respectively. To develop a simple, rapid, accurate, and high-throughput detection method for diagnosis and differential diagnosis on swine enteric coronaviruses, a TaqMan-probe-based multiplex real-time RT-qPCR assay was established to simultaneously detect TGEV, PEDV, PEAV, and PDCoV from the same reaction vial. To establish a high-specific multiplex real-time RT-qPCR for the detection and differential diagnosis of swine enteric coronaviruses, primer sets, and TaqMan probes were designed targeting the highly conserved regions of PEDV or PDCoV M genes and TGEV or PEAV N genes, based on bioinformatics analysis of each virus.

title:
  A TaqMan-probe-based multiplex real-time RT-qPCR for simultaneous detection of porcine enteric coronaviruses

abstract:
  Swine enteric coronaviruses are a group of most significant pathogens causing diarrhea in piglets with similar clinical symptoms and pathological changes. To develop a simple, rapid, accurate, and high-throughput detection method for diagnosis and differential diagnosis on swine enteric coronaviruses, specific primers and probes were designed based on the highly conserved regions of transmissible gastroenteritis virus (TGEV) N, porcine epidemic diarrhea virus (PEDV) M, porcine deltacoronavirus (PDCoV) M, and porcine enteric alphacoronavirus (PEAV) N genes respectively. A TaqMan-probe-based multiplex real-time RT-qPCR assay was developed and optimized to simultaneously detect these swine enteric coronaviruses. The results showed that the limit of detection can reach as low as 10 copies in singular real-time RT-qPCR assays and 100 copies in multiplex real-time RT-qPCR assay, with all correlation coefficients (R(2)) at above 0.99, and the amplification efficiency at between 90 and 120%. This multiplex real-time RT-qPCR assay demonstrated high sensitivity, extreme specificity, and excellent repeatability. The multiplex real-time RT-qPCR assay was then employed to detect the swine enteric coronavirus from 354 field diarrheal samples. The results manifested that TGEV and PDCoV were the main pathogens in these samples, accompanied by co-infections. This well-established multiplex real-time RT-qPCR assay provided a rapid, efficient, specific, and sensitive tool for detection of swine enteric coronaviruses. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00253-019-09835-7) contains supplementary material, which is available to authorized users.


id: cord-257974-kllqjn68
author: Woods, Roger D.
date: 1988
txt: ./txt/cord-257974-kllqjn68.txt
cache: ./cache/cord-257974-kllqjn68.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/32214595/
doi: 10.1007/bf01404139
summary:
  title: Cultivation techniques for animal coronaviruses: Emphasis on feline infectious peritonitis virus, canine coronavirus, transmissible gastroenteritis virus, and porcine hemagglutinating encephalomyelitis virus Generally these viruses infect epithelial cells of the respiratory tract [human coronavirus (HCV), infectious bronchitis virus (IBV), rat coronavirus (RCV), porcine respiratory coronavirus (PCV)] and epithelial cells of the gastrointestinal tract [bovine coronavirus (BCV), canine eoronavirus (CCV), transmissible gastroenteritis virus {TGEV), turkey coronavirus (TCV), feline enteric coronavirus (FECV), human enteric coronavirus (HECV)]. In addition to CRFK cells, a fetal cat whole fibroblast (FCWF) cell line will support the growth of FIPV, as well as FECV, CCV, and TGEV (28,43t, and corn-Journal of Tissue Culture Methods Vol. 11, No. 2, 1988 parison of antigenic and serologic relatedness of the enteric coronaviruses was done in this cell line ~43). This cell line can be used for primary isolation of virus from clinical specimens and in vitro growth of TGEV It0}.

title:
  Cultivation techniques for animal coronaviruses: Emphasis on feline infectious peritonitis virus, canine coronavirus, transmissible gastroenteritis virus, and porcine hemagglutinating encephalomyelitis virus

abstract:
  Techniques are described for the growth and characterization of some mammalian coronaviruses. Because of the fastidious nature of their growth requirements, most will replicate only in cells derived from the natural host or a closely related species. Fetal cat cells are used to grow FIPV, and porcine cells are used to grow TGEV and HEV. However, CCV will replicate in both feline and canine cells. Although all four of these viruses prefer to replicate in a cell in the stationary phase of growth, FIPV is able to replicate in an actively growing cell. Each virus causes a cytopathic effect in monolayer cell cultures under agar or media 18 to 72 h postinfection. Primary isolation of each virus from field specimens is difficult, although most can usually be isolated after 1 to 3 blind passages in the cell culture.


id: cord-260208-fvdq0yes
author: Wang, Jinfeng
date: 2018-03-14
txt: ./txt/cord-260208-fvdq0yes.txt
cache: ./cache/cord-260208-fvdq0yes.txt
extension: .txt
mime: text/plain
url: https://www.sciencedirect.com/science/article/pii/S0166093417306882
doi: 10.1016/j.jviromet.2018.03.005
summary:
  title: Rapid detection of transmissible gastroenteritis virus in swine small intestine samples using real-time reverse transcription recombinase polymerase amplification A rapid and specific real-time reverse-transcription recombinase polymerase amplification assay (RT-RPA) was developed to detect the transmissible gastroenteritis virus (TGEV) in this study. Six primers were needed in the RT-LAMP assays for TGEV, the reaction time was 30 or 60 min, and the results were visualized by agarose gel electrophoresis (Chen et al., 2010; Li and Ren, 2011 T Recombinase polymerase amplification (RPA) is an isothermal gene amplification technique that has been demonstrated to be a rapid, specific, sensitive, and cost-effective molecular diagnostic method (Daher et al., 2016; Piepenburg et al., 2006) . In this study, we developed and evaluated the userfriendly on-site detection platform integrating the real-time RPA technology and a field-deployable device (Genie III tube scanner) for the rapid detection of TGEV.

title:
  Rapid detection of transmissible gastroenteritis virus in swine small intestine samples using real-time reverse transcription recombinase polymerase amplification

abstract:
  A rapid and specific real-time reverse-transcription recombinase polymerase amplification assay (RT-RPA) was developed to detect the transmissible gastroenteritis virus (TGEV) in this study. The primers and exo probe were designed to be specific for a portion of spike (S) gene conserved in TGEV, but absent in the closely related porcine respiratory coronavirus (PRCV). The amplification was performed at 40 °C for 20 min. The assay could only detect the TGEV, and there was no cross-reaction with other pathogens tested. Using the in vitro transcribed TGEV RNA as template, the limit of detection of the developed RT-RPA was 100 copies per reaction. The assay performance was evaluated by testing 76 clinical samples by RT-RPA and a real-time RT-PCR. Fourteen samples were TGEV RNA positive in RT-RPA (18.4%, 14/76), which were also positive in the real-time RT-PCR. The diagnostic agreement between the two assays was 100% (76/76). The R(2) value of RT-RPA and real-time RT-PCR was 0.959 by linear regression analysis. The developed RT-RPA assay provides a useful alternative tool for rapid, simple and reliable detection of TGEV in resource-limited diagnostic laboratories and on-site facilities.


id: cord-260843-c97kctjz
author: Dai, Lei
date: 2016-11-16
txt: ./txt/cord-260843-c97kctjz.txt
cache: ./cache/cord-260843-c97kctjz.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/27851758/
doi: 10.1371/journal.pone.0165585
summary:
  In vivo, TGEV primarily targets and infects intestinal epithelial cells, which play an important role in glucose absorption via the apical and basolateral transporters Na(+)-dependent glucose transporter 1 (SGLT1) and facilitative glucose transporter 2 (GLUT2), respectively. Our data demonstrate that infection with TGEV resulted in increased glucose uptake and augmented expression of EGFR, SGLT1 and GLUT2. Therefore, in the study, we aimed to examine the in vitro effects of TGEV infection on glucose uptake and the expression of SGLT1 and GLUT2 in porcine intestinal columnar epithelial (IPEC-J2) cells, which have been shown to offer a practical model for studying TGEV infection [11, 12] . Together, these results indicate that EGFR and p-EGFR regulates glucose uptake in mock-infected IPEC-J2 cells by modulation of SGLT1 protein expression. Together, these results indicate that EGFR influences glucose uptake in TGEV-infected cells by promoting both SGLT1 and GLUT2 expression.

title:
  Transmissible Gastroenteritis Virus Infection Enhances SGLT1 and GLUT2 Expression to Increase Glucose Uptake

abstract:
  Transmissible gastroenteritis virus (TGEV) is a coronavirus that causes villus atrophy, followed by crypt hyperplasia, reduces the activities of intestinal digestive enzymes, and disrupts the absorption of intestinal nutrients. In vivo, TGEV primarily targets and infects intestinal epithelial cells, which play an important role in glucose absorption via the apical and basolateral transporters Na(+)-dependent glucose transporter 1 (SGLT1) and facilitative glucose transporter 2 (GLUT2), respectively. In this study, we therefore sought to evaluate the effects of TGEV infection on glucose uptake and SGLT1 and GLUT2 expression. Our data demonstrate that infection with TGEV resulted in increased glucose uptake and augmented expression of EGFR, SGLT1 and GLUT2. Moreover, inhibition studies showed that EGFR modulated glucose uptake in control and TGEV infected cells. Finally, high glucose absorption was subsequently found to promote TGEV replication.


id: cord-263025-mmdeyph3
author: Paton, D. J.
date: 1990
txt: ./txt/cord-263025-mmdeyph3.txt
cache: ./cache/cord-263025-mmdeyph3.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/2168106/
doi: 10.1007/bf00350714
summary:
  title: Sows infected in pregnancy with porcine respiratory coronavirus show no evidence of protecting their sucking piglets against transmissible gastroenteritis On the basis of weight gain, clinical signs and survival, no differences in response to challenge was detected when piglets suckled by PRCV inoculated sows were compared with those suckled by uninoculated sows. On the basis of weight gain, clinical signs and survival, no differences in response to challenge was detected when piglets suckled by PRCV inoculated sows were compared with those suckled by uninoculated sows. Such a difference was evident when the litters of sows successfully pm-immunized with TGEV were compared with those of uninoculated or PRCV-inoculated sows. A lyophilized stock of the virus which had been passaged three times in primary pig kidney monolayers (PPKM) was passaged once more, either in PPKM or in a five-day-old colostrum-deprived piglet, to provide the virus for inoculation of the pregnant sows.

title:
  Sows infected in pregnancy with porcine respiratory coronavirus show no evidence of protecting their sucking piglets against transmissible gastroenteritis

abstract:
  Eighteen litters of sucking piglets were challenged with one of two strains of transmissible gastroenteritis virus (TGEV). During pregnancy, their seronegative dams had been either inoculated intranasally with porcine respiratory coronavirus (PRCV), inoculated orally with TGEV or left untreated. On the basis of weight gain, clinical signs and survival, no differences in response to challenge was detected when piglets suckled by PRCV inoculated sows were compared with those suckled by uninoculated sows. Such a difference was evident when the litters of sows successfully pre-immunized with TGEV were compared with those of unicoculated or PRCV-inoculated sows. The possibility of transplacental transmission of PRCV was investigated in two litters born to sows that had been inoculated with this virus in late pregnancy. All sixteen live-born piglets were seronegative for the virus at birth and PRCV was not isolated from tissues taken from two stillborn piglets.


id: cord-263165-bv4dh9eu
title: Coronaviridae, pathogenetic and clinical aspects: An update
author: Möstl, Karin
date: 1990-12-31
txt: ./txt/cord-263165-bv4dh9eu.txt
cache: ./cache/cord-263165-bv4dh9eu.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/1963836/
doi: 10.1016/0147-9571(90)90085-8
summary:
  The recent detection of previously unknown coronaviruses or mutants, like the "Porcine Epidemic Diarrhea"-virus (PEDV) and the TGE-like "Porcine Respiratory Coronavirus" (PRCV) on one hand and new knowledge about pathogenetic mechanisms, for example in FIPV-infections, on the other hand are the basis for this review article. For diagnosis TGEV antigen can be detected by immunofluorescence in the small intestine of piglets at an early stage of disease, by virus isolation in tissue culture or by ELISA. As it causes a respiratory infection and does not replicate in the enteric tract, it was named "Respiratory Variant" of TGEV [16] and recently "Porcine respiratory coronavirus". Pedersen [51] assumed that not only the properties of the infecting virus strain were responsible for the outcome of the disease, but that also the immunologic situation of the host and the type and degree of developing immunity may be of great importance. Natural infection with the Porcine Respiratory Coronavirus induces protective lactogenic immunity against Transmissible Gastroenteritis

abstract:
  Abstract A review is given about pathogenetic and clinical aspects of the well-known as well as of recently detected members of the family Coronaviridae. Special attention is paid to coronavirus infections of domestic cattle and pets, whereas avian, murine, rat and human coronaviruses are summarized briefly.


id: cord-263489-i4tkdgy4
author: Suo, Siqingaowa
date: 2015-05-27
txt: ./txt/cord-263489-i4tkdgy4.txt
cache: ./cache/cord-263489-i4tkdgy4.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/26013256/
doi: 10.1007/s11262-015-1208-7
summary:
  title: Phage display for identifying peptides that bind the spike protein of transmissible gastroenteritis virus and possess diagnostic potential Herein, we use similar technology and advance previous work by using the rS-AD as an immobilizing target to select phages from a peptide display library, with diagnostic potential for TGEV. Our results indicate that phages bearing peptide ligands that bind rS-AD can be used to develop a phage-mediated ELISA with high sensitivity and specificity to distinguish TGEV from other common swine viruses. To compare the sensitivities of phage-mediated ELISA to antibody-mediated ELISA, TGEV serially diluted in 0.1 M NaHCO 3 (pH 8.6) was coated onto duplicate ELISA plates overnight at 4°C followed by blocking with 5 % skim milk for 3 h at rt. Predicted amino acid sequences were generated for ten selected phages In summary, we identified peptides that specifically bind to TGEV and can form the basis of new diagnostic tests where the sensitivity of phTGEV-SAD15 was 0.1 lg of TGEV.

title:
  Phage display for identifying peptides that bind the spike protein of transmissible gastroenteritis virus and possess diagnostic potential

abstract:
  The spike (S) protein of porcine transmissible gastroenteritis virus (TGEV) is located within the viral envelope and is the only structural protein that possesses epitopes capable of inducing virus-neutralizing antibodies. Among the four N-terminal antigenic sites A, B, C, and D, site A and to a lesser extent site D (S-AD) induce key neutralizing antibodies. Recently, we expressed S-AD (rS-AD) in recombinant form. In the current study, we used the rS-AD as an immobilized target to identify peptides from a phage-display library with application for diagnosis. Among the 9 phages selected that specifically bound to rS-AD, the phage bearing the peptide TLNMHLFPFHTG bound with the highest affinity and was subsequently used to develop a phage-based ELISA for TGEV. When compared with conventional antibody-based ELISA, phage-mediated ELISA was more sensitive; however, it did not perform better than semi-quantitative RT-PCR, though phage-mediated ELISA was quicker and easier to set up.


id: cord-265224-mwgccr4a
title: Aminopeptidase N is a major receptor for the enteropathogenic coronavirus TGEV
author: Delmas, Bernard
date: 1992
txt: ./txt/cord-265224-mwgccr4a.txt
cache: ./cache/cord-265224-mwgccr4a.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/1350661/
doi: 10.1038/357417a0
summary:
  Further evidence that the anti-TGEV-receptor antibodies recognized aminopeptidase N was obtained by showing that (1) an antibody raised against rabbit aminopeptidase N 4 reacted with the same three polypeptides in brush-border membrane preparations (Fig. 2, lane 2) : 95K and 50K, corresponding to the B (amino) and C (carboxy) subunits of the pig aminopeptidase, and 150K, uncleaved aminopeptidase 5 ; (2) the immunoprecipitated material hydrolysed leucine p-nitroanilide, a chromogenic substrate specific for aminopeptidase (ref. A monoclonal antibody designated RBS protected WI38 and RD human cell lines from HCV-229E-induced cytopathic effects and protected WI38 cells from virus infection ( Fig. la-c) . Because aminopeptidase from humans, pigs and other mammals are structurally similar 9 , 12-14, we investigated whether HCV-229E and RBS would bind specifically to hAPN and whether expression of hAPN by murine cells would make them susceptible to infection with HCV-229E.

abstract:
  CORONAVIRUSES, like many animal viruses, are characterized by a restricted host range and tissue tropism(1). Transmissible gastroenteritis virus (TGEV), a major pathogen causing a fatal diarrhoea in newborn pig, replicates selectively in the differentiated enterocytes covering the villi of the small intestine(2). To investigate the molecular determinants of the infection, we characterized the surface molecule used by the virus for binding and entry into host cells. Here we report that aminopeptidase N, an ectoenzyme abundantly expressed at the apical membrane of the enterocytes, serves as a receptor for TGEV. Monoclonal antibodies were selected for their ability to block infection by TGEV of porcine cell lines. They recognized a brush-border membrane protein of M(r), 150K, which was identified as aminopeptidase N by ammo-terminal sequencing. Two lines of evidence supported the view that the peptidase itself acts as a receptor. First, virions bound specifically to aminopep-tidase N that was purified to homogeneity. Second, recombinant expression of aminopeptidase N conferred infectivity by TGEV to an otherwise non-permissive cell line.


id: cord-265312-yfjme53q
author: Magtoto, Ronaldo
date: 2019-03-13
txt: ./txt/cord-265312-yfjme53q.txt
cache: ./cache/cord-265312-yfjme53q.txt
extension: .txt
mime: text/plain
url: https://doi.org/10.1128/msphere.00017-19
doi: 10.1128/msphere.00017-19
summary:
  This study compared the performances of three commercial transmissible gastroenteritis virus/porcine respiratory coronavirus (TGEV/PRCV) blocking enzyme-linked immunosorbent assays (ELISAs) using serum samples (n = 528) collected over a 49-day observation period from pigs inoculated with TGEV strain Purdue (n = 12), TGEV strain Miller (n = 12), PRCV (n = 12), or with virus-free culture medium (n = 12). All pigs in the negative-control group remained TGEV and PRCV seronegative throughout the monitoring period when tested with any of the three TGEV/PRCV differential blocking ELISA kits evaluated in this study ( The percentages of TGEV antibody-positive serum samples reported by the three commercial ELISA kits evaluated over the 50-day study period for pigs inoculated with TGEV strains Purdue and Miller are presented in Fig. 2A to F, respectively.

title:
  Evaluation of the Serologic Cross-Reactivity between Transmissible Gastroenteritis Coronavirus and Porcine Respiratory Coronavirus Using Commercial Blocking Enzyme-Linked Immunosorbent Assay Kits

abstract:
  This study compared the performances of three commercial transmissible gastroenteritis virus/porcine respiratory coronavirus (TGEV/PRCV) blocking enzyme-linked immunosorbent assays (ELISAs) using serum samples (n = 528) collected over a 49-day observation period from pigs inoculated with TGEV strain Purdue (n = 12), TGEV strain Miller (n = 12), PRCV (n = 12), or with virus-free culture medium (n = 12). ELISA results were evaluated both with “suspect” results interpreted as positive and then as negative. All commercial kits showed excellent diagnostic specificity (99 to 100%) when testing samples from pigs inoculated with virus-free culture medium. However, analyses revealed differences between the kits in diagnostic sensitivity (percent TGEV- or PRCV-seropositive pigs), and all kits showed significant (P < 0.05) cross-reactivity between TGEV and PRCV serum antibodies, particularly during early stages of the infections. Serologic cross-reactivity between TGEV and PRCV seemed to be TGEV strain dependent, with a higher percentage of PRCV-false-positive results for pigs inoculated with TGEV Purdue than for TGEV Miller. Moreover, the overall proportion of false positives was higher when suspect results were interpreted as positive, regardless of the ELISA kit evaluated. IMPORTANCE Current measures to prevent TGEV from entering a naive herd include quarantine and testing for TGEV-seronegative animals. However, TGEV serology is complicated due to the cross-reactivity with PRCV, which circulates subclinically in most swine herds worldwide. Conventional serological tests cannot distinguish between TGEV and PRCV antibodies; however, blocking ELISAs using antigen containing a large deletion in the amino terminus of the PRCV S protein permit differentiation of PRCV and TGEV antibodies. Several commercial TGEV/PRCV blocking ELISAs are available, but performance comparisons have not been reported in recent research. This study demonstrates that the serologic cross-reactivity between TGEV and PRCV affects the accuracy of commercial blocking ELISAs. Individual test results must be interpreted with caution, particularly in the event of suspect results. Therefore, commercial TGEV/PRCV blocking ELISAs should only be applied on a herd basis.


id: cord-269094-6aka052v
author: Ortego, Javier
date: 2007-11-25
txt: ./txt/cord-269094-6aka052v.txt
cache: ./cache/cord-269094-6aka052v.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/17692883/
doi: 10.1016/j.virol.2007.05.032
summary:
  In this article, we confirm that E protein is essential for TGEV replication in different cell lines, and report the first evidence that TGEV virions containing RNA are generated in absence of E protein, although virus maturation was arrested in the budding compartment, and immature virions were accumulated between the rough endoplasmic reticulum and cis-Golgi. To determine the effect of E gene deletion on TGEV infection of BHK-pAPN-E − cells, the subcellular localization of virus particles and endoplasmic reticulum (protein disulfide-isomerase, PDI), intermediate compartment and cis-Golgi (KDEL receptor), and trans-Golgi (giantin) specific markers were compared by immunofluorescence laser scanning confocal microscopy in rTGEV-wt and rTGEV-ΔE infected BHK-pAPN-E − and E + cells at different times post-infection (0, 8, 14, and 24 h post-infection).

title:
  Absence of E protein arrests transmissible gastroenteritis coronavirus maturation in the secretory pathway

abstract:
  A recombinant transmissible gastroenteritis coronavirus (rTGEV) in which E gene was deleted (rTGEV-ΔE) has been engineered. This deletion mutant only grows in cells expressing E protein (E(+) cells) indicating that E was an essential gene for TGEV replication. Electron microscopy studies of rTGEV-ΔE infected BHK-pAPN-E(−) cells showed that only immature intracellular virions were assembled. These virions were non-infectious and not secreted to the extracellular medium in BHK-pAPN-E(−) cells. RNA and protein composition analysis by RNase-gold and immunoelectron microscopy showed that rTGEV-ΔE virions contained RNA and also all the structural TGEV proteins, except the deleted E protein. Nevertheless, full virion maturation was blocked. Studies of the rTGEV-ΔE subcellular localization by confocal and immunoelectron microscopy in infected E(−) cells showed that in the absence of E protein virus trafficking was arrested in the intermediate compartment. Therefore, the absence of E protein in TGEV resulted in two actions, a blockade of virus trafficking in the membranes of the secretory pathway, and prevention of full virus maturation.


id: cord-269720-o81j3d1j
author: Page, Kevin W.
date: 1990
txt: ./txt/cord-269720-o81j3d1j.txt
cache: ./cache/cord-269720-o81j3d1j.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/1962975/
doi: 10.1007/bf00570024
summary:
  Primer extension, of a synthetic oligonucleotide complementary to the 5′ end of the nucleoprotein gene of TGEV was used to produce a single-stranded DNA copy of the leader RNA from the nucleoprotein mRNA species from TGEV and PRCV, the sequences of which were determined by Maxam and Gilbert cleavage. Comparison of the leader RNAs of TGEV and PRCV with published leader RNAs of other coronaviruses was used to identify areas of conserved sequence and potential secondary structure that may be involved in the transcription of coronavirus subgenomic mRNA species. The site, ACTAAAC, is seven nucleotides upstream of the nucleoprotein initiation codon and has also been found to precede all the TGEV structural protein genes and two of the three potential genes shown to be at the 5'' end of mRNA species (15) (16) (17) . The two porcine coronavirus leader sequences were identical, indicating that the two viruses probably use the same RNA polymerase-leader complex binding site, ACTAAAC, for the synthesis of subgenomic mRNA species.

title:
  Sequence analysis of the leader RNA of two porcine coronaviruses: Transmissible gastroenteritis virus and porcine respiratory coronavirus

abstract:
  The leader RNA sequence was determined for two pig coronaviruses, tranmissible gastroenteritis virus (TGEV), and porcine respiratory coronavirus (PRCV). Primer extension, of a synthetic oligonucleotide complementary to the 5′ end of the nucleoprotein gene of TGEV was used to produce a single-stranded DNA copy of the leader RNA from the nucleoprotein mRNA species from TGEV and PRCV, the sequences of which were determined by Maxam and Gilbert cleavage. Northern blot analysis, using a synthetic oligonucleotide complementary to the leader RNA, showed that the leader RNA sequence was present on all of the subgenomic mRNA species. The porcine coronavirus leader RNA sequences were compared to each other and to published coronavirus leader RNA sequences. Sequence homologies and secondary structure similarities were identified that may play a role in the biological function of these RNA sequences.


id: cord-269867-k10siwur
author: Méchin, Marie-Claire
date: 1996-12-31
txt: ./txt/cord-269867-k10siwur.txt
cache: ./cache/cord-269867-k10siwur.txt
extension: .txt
mime: text/plain
url: https://www.sciencedirect.com/science/article/pii/S0378111996003484
doi: 10.1016/s0378-1119(96)00348-4
summary:
  Intact bacteria or extracted CS31A hybrid fibrillae expressing TGEV epitopes at any of the permissive sites, were recognized by Ab directed against the foreign parent protein, providing a direct argument for exposure of the corresponding ClpG region at the cell surface and for antigenicity of the epitopes in the polymeric CS31A fibrillae context. coli CS31A fibrillae as the carrier protein (Bousquet et al., 1994; Der Vartanian et al., 1994) , and two B-cell epitopes from TGEV consisting of the site C (aa 363-371) and site A (aa 522-531) of TGEV-S as the foreign antigenic determinants (Delmas et al., 1990; Gebauer et al., 1991) . The binding of the TGEV-specific mAb with hybrid fibrillae indicates that the TGEV antigenic determinants expressed at any of the permissive sites are exposed on both ClpG and CS31A proteins at the E.

title:
  The major subunit ClpG of Escherichia coli CS31A fibrillae as an expression vector for different combinations of two TGEV coronavirus epitopes

abstract:
  Abstract Previously, two B-cell epitopes from the entero-pathogenic transmissible gastroenteritis virus (TGEV), namely the C epitope (TGEV-C) amino acids (aa) 363–371 and the A epitope (TGEV-A) aa 522–531 of the spike S protein (TGEV-S), have been separately expressed on the CS31A fibrillae at the surface of Escherichia coli following insertion into a same region of ClpG. However, the resulting chimeras induced a marginal TGEV-neutralizing antibody (Ab) response in mice. Here, with the view to improving this response, we introduced TGEV-C alone or in different tandem association with TGEV-A (A::C or C::A) in twelve putatively exposed regions of ClpG. Among the 28 resulting engineered proteins only 15, carrying up to 51 extra aa, had not essentially disturbed the correct CS31A fibrillae formation process. Six partially permissive sites accepting only TGEV-C and three highly permissive sites tolerating A::C or C::A tandem peptide, were identified throughout ClpG. Intact bacteria or extracted CS31A hybrid fibrillae expressing TGEV epitopes at any of the permissive sites, were recognized by Ab directed against the foreign parent protein, providing a direct argument for exposure of the corresponding ClpG region at the cell surface and for antigenicity of the epitopes in the polymeric CS31A fibrillae context. The potential of CS31A fibrillae as carriers of the TGEV peptides indicates that there may be three positions (N terminus, aa 202–204 and 202–218) in ClpG which may turn out to be important fusion sites and therefore be relevant for the eventual design of TGEV vaccines. Unexpectedly, TGEV-A, whatever its position in ClpG, mediated the partial proteolytic degradation of the hybrid proteins, suggesting that it functions as a substrate for a cellular protease, and thereby that its suitability as a vaccine antigen candidate is doubtful.


id: cord-270586-ohs8z91m
author: Ballesteros, M. L.
date: 1997-01-20
txt: ./txt/cord-270586-ohs8z91m.txt
cache: ./cache/cord-270586-ohs8z91m.txt
extension: .txt
mime: text/plain
url: https://www.sciencedirect.com/science/article/pii/S0042682296983440
doi: 10.1006/viro.1996.8344
summary:
  PRCVs replicate to high titers only in al ., 1990) , and TGEV entry into swine testis (ST) cells the respiratory tract (Cox et al., 1990) and have a large is mediated through interactions between the virus S deletion at the 5 end of the spike gene, in positions glycoprotein and the porcine aminopeptidase N (pAPN) ranging from nucleotides (nt) 45 to 745 (Enjuanes and which serves as the cellular receptor (Delmas et al., Van der Zeijst, 1995; Sá nchez et al., 1992; Vaughn et al., 1992) . Studies changes located in the S protein gene, at positions 214, 655, and 2098, were involved in the control of the enteric on the inhibition of virus binding to cells indicated that the receptor binding site for TGEV had to be located tropism, recombinant viruses containing one or the three nucleotide differences from the respiratory isolate were between antigenic sites D and A of the spike protein (Suñé et al., 1990) , mapping between amino acids 385 selected.

title:
  Two Amino Acid Changes at the N-Terminus of Transmissible Gastroenteritis Coronavirus Spike Protein Result in the Loss of Enteric Tropism

abstract:
  Abstract To study the molecular basis of TGEV tropism, a collection of recombinants between the PUR46-MAD strain of transmissible gastroenteritis coronavirus (TGEV) infecting the enteric and respiratory tracts and the PTV strain, which only infects the respiratory tract, was generated. The recombinant isolation frequency was about 10−9recombinants per nucleotide and was 3.7-fold higher at the 5′-end of the S gene than in other areas of the genome. Thirty recombinants were plaque purified and characterized phenotypically and genetically. All recombinant viruses had a single crossover and had inherited the 5′- and 3′-halves of their genome from the enteric and respiratory parents, respectively. Recombinant viruses were classified into three groups, named 1 to 3, according to the location of the crossover. Group 1 recombinants had the crossover in the S gene, while in Groups 2 and 3 the crossovers were located in ORF1b and ORF1a, respectively. The tropism of the recombinants was studied. Recombinants of Group 1 had enteric and respiratory tropism, while Group 2 recombinants infected the respiratory, but not the enteric, tract. Viruses of both groups differed by two nucleotide changes at positions 214 and 655. Both changes may be in principle responsible for the loss of enteric tropism but only the change in nucleotide 655 was specifically found in the respiratory isolates and most likely this single nucleotide change, which leads to a substitution in amino acid 219 of the S protein, was responsible for the loss of enteric tropism in the closely related PUR-46 isolates. The available data indicate that in order to infect enteric tract cells with TGEV, two different domains of the S protein, mapping between amino acids 522 and 744 and around amino acid 219, respectively, are involved. The first domain binds to porcine aminopeptidase N, the cellular receptor for TGEV. In the other domain maps a second factor of undefined nature but which may be the binding site for a coreceptor essential for the enteric tropism of TGEV.


id: cord-271815-yr1dq258
title: Inactivation of surrogate coronaviruses on hard surfaces by health care germicides
author: Hulkower, Rachel L.
date: 2011-06-30
txt: ./txt/cord-271815-yr1dq258.txt
cache: ./cache/cord-271815-yr1dq258.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/21256627/
doi: 10.1016/j.ajic.2010.08.011
summary:
  Methods The efficacy of health care germicides against 2 surrogate coronaviruses, mouse hepatitis virus (MHV) and transmissible gastroenteritis virus (TGEV), was tested using the quantitative carrier method on stainless steel surfaces. This study was undertaken using the carrier method to evaluate 6 chemical germicides commonly used in health care settings for their efficacy in reducing infectivity of coronaviruses on environmental surfaces. The efficacy of 6 hospital surface germicides was tested against 2 coronaviruses, MHV and TGEV, used as surrogates for SARS-CoV. 3, 15, 17, 24 The results of this study show that, of the commonly used hospital germicides tested, only the ethanol-based germicides were able to achieve this level of reduction of infectious virus after 1 minute of contact time. Studies of hospital germicide efficacy against adenovirus 8 using the same carrier-based method with 1-minute contact times found greater log 10 reduction factors by OPA (4.37) than were observed in this study for TGEV (2.27) and MHV (1.71).

abstract:
  Background In the 2003 severe acute respiratory syndrome outbreak, finding viral nucleic acids on hospital surfaces suggested surfaces could play a role in spread in health care environments. Surface disinfection may interrupt transmission, but few data exist on the effectiveness of health care germicides against coronaviruses on surfaces. Methods The efficacy of health care germicides against 2 surrogate coronaviruses, mouse hepatitis virus (MHV) and transmissible gastroenteritis virus (TGEV), was tested using the quantitative carrier method on stainless steel surfaces. Germicides were o-phenylphenol/p-tertiary amylphenol) (a phenolic), 70% ethanol, 1:100 sodium hypochlorite, ortho-phthalaldehyde (OPA), instant hand sanitizer (62% ethanol), and hand sanitizing spray (71% ethanol). Results After 1-minute contact time, for TGEV, there was a log10 reduction factor of 3.2 for 70% ethanol, 2.0 for phenolic, 2.3 for OPA, 0.35 for 1:100 hypochlorite, 4.0 for 62% ethanol, and 3.5 for 71% ethanol. For MHV, log10 reduction factors were 3.9 for 70% ethanol, 1.3 for phenolic, 1.7 for OPA, 0.62 for 1:100 hypochlorite, 2.7 for 62% ethanol, and 2.0 for 71% ethanol. Conclusion Only ethanol reduced infectivity of the 2 coronaviruses by >3-log10 after 1 minute. Germicides must be chosen carefully to ensure they are effective against viruses such as severe acute respiratory syndrome coronavirus.


id: cord-273712-r2akpce8
author: Wang, Jingjing
date: 2016-02-19
txt: ./txt/cord-273712-r2akpce8.txt
cache: ./cache/cord-273712-r2akpce8.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/26908211/
doi: 10.1007/s12250-015-3690-4
summary:
  In the same beta group, the receptors for mouse hepatitis virus (MHV) and bovine coronavirus (BCoV) are carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) and a sugar, respectively, despite their high sequence homology Peng et al., 2012) . In our study, we compared the efficiency of pseudotyped viruses with S proteins from different groups of CoVs. Furthermore, the cell tropisms of TGEV and PEDV were characterized by live and pseudotyped viruses. Therefore, we compared the S protein amino acid sequences of CoVs from different groups, including SARS-CoV, MHV, HCoV-229E, TGEV, PEDV, HCoV-OC43, BCoV, and IBV (Gen-Bank accession numbers ABD72982.1, AAR92025.1, NP_073551.1, ABG89335.1, NP_598310.1, AAT84362.1, ABM66810.1, and NP_040831.1, respectively) using ClustalW ( Figure 1B ). Lentiviruses pseudotyped with SARS-CoV S protein could efficiently infect 293T cells expressing ACE2, and the pseudovirus level after entry reached 10 6 relative light units (RLU) ( Figure 2B ). To further study the cellular entry of CoVs, we used live PEDV and TGEV to infect different cell lines.

title:
  Comparison of lentiviruses pseudotyped with S proteins from coronaviruses and cell tropisms of porcine coronaviruses

abstract:
  The surface glycoproteins of coronaviruses play an important role in receptor binding and cell entry. Different coronaviruses interact with their specific receptors to enter host cells. Lentiviruses pseudotyped with their spike proteins (S) were compared to analyze the entry efficiency of various coronaviruses. Our results indicated that S proteins from different coronaviruses displayed varied abilities to mediate pseudotyped virus infection. Furthermore, the cell tropisms of porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus (TGEV) have been characterized by live and pseudotyped viruses. Both live and pseudoviruses could infected Vero- CCL-81 (monkey kidney), Huh-7 (human liver), and PK-15 (pig kidney) cells efficiently. CCL94 (cat kidney) cells could be infected efficiently by TGEV but not PEDV. Overall, our study provides new insights into the mechanisms of viral entry and forms a basis for antiviral drug screening. [Image: see text]


id: cord-274424-juj71nc5
author: Pulford, David J.
date: 1991-06-30
txt: ./txt/cord-274424-juj71nc5.txt
cache: ./cache/cord-274424-juj71nc5.txt
extension: .txt
mime: text/plain
url: https://api.elsevier.com/content/article/pii/004268229190617K
doi: 10.1016/0042-6822(91)90617-k
summary:
  Abstract The Spike (S) protein from a virulent British field isolate of porcine transmissible gastroenteritis virus (TGEV) FS772/70 was constructed from cDNA and inserted into the vaccinia virus (VV) thymidine kinase gene locus under the control of the VV early/late gene P7.5K promoter. In this paper we report the construction of a FS772/ 70 cDNA S gene and its expression by a recombinant vaccina virus (rVV) to study the antigenicity and cellular localization of the S protein. Expression of the recombinant spike antigens TGEV gene products synthesized by vTS-1 and vTSA-1 were analyzed by pulse labeling rVV-infected HTK-cells with L-[35S]methionine in the presence or absence of 10 pg ml-'' tunicamycin for 6 hr. The lack of detectable ~160 or ~130 in the culture medium of vTS-l-and vTSA-l-infected cells, respectively (Fig. 4 lanes 4 and 7) , could result from the levels being too low to be detected by the antibodies due to reduction in synthesis or the lack of glycosylation of the S protein in the presence of tunicamycin.

title:
  Intracellular processing of the porcine coronavirus transmissible gastroenteritis virus spike protein expressed by recombinant vaccinia virus

abstract:
  Abstract The Spike (S) protein from a virulent British field isolate of porcine transmissible gastroenteritis virus (TGEV) FS772/70 was constructed from cDNA and inserted into the vaccinia virus (VV) thymidine kinase gene locus under the control of the VV early/late gene P7.5K promoter. Recombinant S protein was synthesized as an endo-β-N-acetylglucosamini-dase H (Endo H)-sensitive glycoprotein with high mannose simple oligosaccharides (gp190) that underwent post-translational modification to an Endo H-resistant glycoprotein with complex oligosaccharides (gp210). Immunofluorescence analysis demonstrated that the majority of recombinant S protein was retained at the Golgi but some S protein was expressed on the plasma membrane. Monoclonal antibodies (mAbs) raised against native S protein reacted with this recombinant S protein; also, mice infected with the recombinant vaccinia virus (rVV) expressing the S protein induced TGEV neutralizing antibodies. A truncated S protein (SΔ) was also expressed in rVV-infected cells by introducing a deletion into the S protein cDNA that removed 292 amino acids from the C-terminus. The SΔ protein (gpl70) was shown to be antigenically similar to TGEV S protein by immunofluorescence and immunoprecipitation tests but was retained in the endoplasmic reticulum and not expressed on the cell surface.


id: cord-275635-d50bxe7c
author: Yuan, Xiaomin
date: 2015-07-31
url: https://doi.org/10.1016/j.vaccine.2015.06.057
doi: 10.1016/j.vaccine.2015.06.057
title:
  Efficacy and immunogenicity of recombinant swinepox virus expressing the A epitope of the TGEV S protein

abstract:
  To explore the possibility of developing a vaccine against transmissible gastroenteritis virus (TGEV) infection, a recombinant swinepox virus (rSPV-SA) expressing a TGEV protective antigen has been constructed. Immune responses and protection efficacy of the vaccination vector were assessed in both mice and pig models. An indirect ELISA assay suggested that when mice were vaccinated with rSPV-SA, the level of IgG against TGEV was enhanced dramatically. The cytokine assays were employed and the results indicated that both the Th1-type and Th2-type cytokine levels raised after vaccination with rSPV-SA in mice models. Results from the passive immunity protection test of new born piglets demonstrated that the recombinant live-vector vaccine, rSPV-SA, could 100% protect piglets from the SPV infection, and there was no significant clinical symptom in the rSPV-SA treatment group during this experiment. The data suggest that the novel recombinant swinepox virus is a potential vaccine against TGEV infection.


id: cord-275780-76v61ktj
author: Wu, Aimin
date: 2020-01-20
url: https://doi.org/10.1038/s41419-020-2233-6
doi: 10.1038/s41419-020-2233-6
title:
  Transmissible gastroenteritis virus targets Paneth cells to inhibit the self-renewal and differentiation of Lgr5 intestinal stem cells via Notch signaling

abstract:
  Infection with transmissible gastroenteritis virus (TGEV) has been associated with villous atrophy within 48 h, which seriously disrupts intestinal homeostasis. However, the underlying mechanisms remain elusive. In this study, we found that TGEV infection severely disrupted intestinal homeostasis via inhibition of self-renewal and differentiation in Lgr5 intestinal stem cells (ISCs). Profoundly, TGEV-encoded NSP10/NSP16 protein complex-mediated the inactivation of Notch signaling provided a mechanistic explanation for this phenomenon. Initial invasions by TGEV-targeted Paneth cells through aminopeptidase N (APN) receptor, then inducing mitochondrial damage and ROS generation in them, ultimately causing Paneth cell decrease and loss of Notch factors (DII4 and Hes5), which are essential for Lgr5 ISCs self-renewal and differentiation. Interestingly, loss of Notch signaling induced goblet cells differentiation at the cost of absorptive enterocytes and promoted mucins secretion, which accelerated TGEV replication. Therefore, the more differentiation of goblet cells, the greater TGEV infection in jejunum. These results provide a detailed mechanistic pathway by which villous atrophy sharply occurs in TGEV-infected jejunum within 48 h. Thus, the pathogenesis of TGEV can be described as a “bottom up scenario”, which is contrary to the traditional “top down” hypothesis. Together, our findings provide a potential link between diarrheal virus infection and crypt cells response that regulates Paneth cells function and Lgr5 ISCs fate and could be exploited for therapeutic application.


id: cord-280183-fxhkfjl6
author: Have, P.
date: 1992-04-30
txt: ./txt/cord-280183-fxhkfjl6.txt
cache: ./cache/cord-280183-fxhkfjl6.txt
extension: .txt
mime: text/plain
url: https://www.sciencedirect.com/science/article/pii/037811359290135G
doi: 10.1016/0378-1135(92)90135-g
summary:
  Abstract Antibodies to a transmissible gastroenteritis virus (TGEV)-related coronavirus have been demonstrated in mink sera by indirect immunofluorescence, peroxidase-linked antibody assays and immunoblotting. The present paper provides the first serological evidence for infection in mink with a coronavirus (here designated MCV) serologically related to TGEV and PEDV. Initially, mink sera were examined in IFAT using acetone fixed monolayers of secondary swine kidney cells infected with TGEV as substrate and FITCconjugated protein-A to detect specific binding of antibodies to TGEV. A high-titered mink antiserum and representative high-titered antisera against TGEV, PRCV, CCV, FIPV and PEDV were selected for further studies of the serological relationship of the putative mink coronavirus to other coronaviruses. The present study has shown that infection with a coronavirus serologically related to TGEV and PEDV is common in the Danish mink population.

title:
  Coronavirus infection in mink (Mustela vision). Serological evidence of infection with a coronavirus related to transmissible gastroenteritis virus and porcine epidemic diarrhea virus

abstract:
  Abstract Antibodies to a transmissible gastroenteritis virus (TGEV)-related coronavirus have been demonstrated in mink sera by indirect immunofluorescence, peroxidase-linked antibody assays and immunoblotting. This is the first serological evidence of a specific coronavirus infection in mink. The putative mink coronavirus (MCV) seems to be widespread in the Danish mink population with a prevalence approaching 100%. Analysis by immunoblotting has shown that MCV is closely related to TGEV by the spike (S), matrix (M) and nucleoprotein (N) polypeptides. Furthermore, antibodies to MCV also cross-reacted with N and M polypeptides of porcine epidemic diarrhea virus (PEDV). Thus MCV may occupy an intermediate position between the TGEV group of coronaviruses and PEDV. The possibility that MCV may be associated with syndromes of acute enteritis in preweaning mink is discussed.


id: cord-282344-o1rkx2z4
title: Effects of humidity and other factors on the generation and sampling of a coronavirus aerosol
author: Kim, Seung Won
date: 2007-07-25
txt: ./txt/cord-282344-o1rkx2z4.txt
cache: ./cache/cord-282344-o1rkx2z4.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/32214623/
doi: 10.1007/s10453-007-9068-9
summary:
  The airborne viruses were collected on heating, ventilating, and air conditioning (HVAC) filters in an experimental apparatus and also sampled upstream of these test filters using AGI-30 and BioSampler impinger samplers. To study the effects of relative humidity (RH) on TGEV collection by the filters and samplers, the virus was nebulized into air at 30, 50, 70, and 90% RH. To measure the degree to which the nebulizers generated airborne viruses that could be sampled and remain viable, aerosolization efficiency, g A , was calculated in the same way as Adams et al. The recovery of TGEV from the test filter can be calculated in two ways: (1) relative to the airborne virus concentration, R a , and (2) relative to the nebulizer suspension concentration, R n . TGEV was nebulized, then sampled using AGI-30 impingers and BioSamplers, and finally collected on an HVAC test filter to measure the effects of nebulization stress and the recovery of viable virus from the filter.

abstract:
  Suspensions of transmissible gastroenteritis virus (TGEV), a porcine coronavirus, were nebulized at rates of 0.1–0.2 ml/min into moving air using a Collison nebulizer or a plastic medical nebulizer operating at pressures ranging from 7 to 15 psi. The airborne viruses were collected on heating, ventilating, and air conditioning (HVAC) filters in an experimental apparatus and also sampled upstream of these test filters using AGI-30 and BioSampler impinger samplers. To study the effects of relative humidity (RH) on TGEV collection by the filters and samplers, the virus was nebulized into air at 30, 50, 70, and 90% RH. There were no significant changes in virus titer in the nebulizer suspension before and after nebulization for either nebulizer at any of the pressures utilized. Aerosolization efficiency – the ratio of viable virus sampled with impingers to the quantity of viable virus nebulized – decreased with increasing humidity. BioSamplers detected more airborne virus than AGI-30 samplers at all RH levels. This difference was statistically significant at 30 and 50% RH. Nebulizer type and pressure did not significantly affect the viability of the airborne virus. Virus recovery from test filters relative to the concentration of virus in the nebulizer suspension was less than 10%. The most and the least virus were recovered from filter media at 30% and 90% RH, respectively. The results suggest that TGEV, and perhaps other coronaviruses, remain viable longer in an airborne state and are sampled more effectively at low RH than at high humidity.


id: cord-283378-brdtsi65
author: Maragkoudakis, Petros A.
date: 2010-07-31
txt: ./txt/cord-283378-brdtsi65.txt
cache: ./cache/cord-283378-brdtsi65.txt
extension: .txt
mime: text/plain
url: https://api.elsevier.com/content/article/pii/S0168160509006771
doi: 10.1016/j.ijfoodmicro.2009.12.024
summary:
  This study aimed to examine the potential antiviral activity of lactic acid bacteria (LAB) using animal and human intestinal and macrophage cell line models of non tumor origin. Highest protection effects were recorded with the known probiotics Lactobacillus rhamnosus GG and Lactobacillus casei Shirota against both RV and TGEV, while notable antiviral activity was also attributed to Enterococcus faecium PCK38, Lactobacillus fermentum ACA-DC179, Lactobacillus pentosus PCA227 and Lactobacillus plantarum PCA236 and PCS22, depending on the cell line and virus combination used. Additional functional properties that relate to the possible underlying mode of action of the antiviral effect have been also studied, including release of reactive oxygen species (ROS) from the cell lines due to probiotic interaction, as well as the attachment ability of probiotic strains on the cell line monolayers. Recent studies (Botić et al., 2007; Ivec et al., 2007) reported the protective effect that various lactic acid bacteria, including the probiotic Lactobacillus paracasei F19, conferred upon porcine intestinal epithelial and macrophage cell line infected with vesicular stomatitis virus (VSV).

title:
  Lactic acid bacteria efficiently protect human and animal intestinal epithelial and immune cells from enteric virus infection

abstract:
  This study aimed to examine the potential antiviral activity of lactic acid bacteria (LAB) using animal and human intestinal and macrophage cell line models of non tumor origin. To this end, LAB strains selected on the basis of previous in vitro trials were co-incubated with cell line monolayers, which were subsequently challenged with rotavirus (RV) and transmissible gastroenteritis virus (TGEV). In order to elucidate the possible mechanism responsible for the antiviral activity, the induction of reactive oxygen species (ROS) release as well as the attachment ability of LAB on the cell lines was investigated. Various strains were found to exhibit moderate to complete monolayer protection against viral RV or TGEV disruption. Highest protection effects were recorded with the known probiotics Lactobacillus rhamnosus GG and Lactobacillus casei Shirota against both RV and TGEV, while notable antiviral activity was also attributed to Enterococcus faecium PCK38, Lactobacillus fermentum ACA-DC179, Lactobacillus pentosus PCA227 and Lactobacillus plantarum PCA236 and PCS22, depending on the cell line and virus combination used. A variable increase (of up to 50%) on the release of NO(−) and H(2)O(2) (ROS) was obtained when LAB strains were co-incubated with the cell lines, but the results were found to be LAB strain and cell line specific, apart from a small number of strains which were able to induce strong ROS release in more than one cell line. In contrast, the ability of the examined LAB strains to attach to the cell line monolayers was LAB strain but not cell line specific. Highest attachment ability was observed with L. plantarum ACA-DC 146, L. paracasei subsp. tolerans ACA-DC 4037 and E. faecium PCD71. Clear indications on the nature of the antiviral effect were evident only in the case of the L. casei Shirota against TGEV and with L. plantarum PCA236 againt both RV and TGEV. In the rest of the cases, each interaction was LAB-cell line–virus specific, barring general conclusions. However, it is probable that more than one mechanism is involved in the antiviral effect described here. Further investigations are required to elucidate the underlying mode of action and to develop a cell line model as a system for selection of probiotic strains suited for farm animal applications.


id: cord-285812-l7dpv6nx
title: Pathogenicity of experimental infection with ‘pneumotropic’ porcine coronavirus
author: O’TOOLE, D.
date: 1989-07-31
txt: ./txt/cord-285812-l7dpv6nx.txt
cache: ./cache/cord-285812-l7dpv6nx.txt
extension: .txt
mime: text/plain
url: https://www.sciencedirect.com/science/article/pii/S0034528818312268
doi: 10.1016/s0034-5288(18)31226-8
summary:
  Virus localisation and lesions were studied in 14 one-week-old piglets following combined intranasal-oral inoculation with a British isolate of ''pneumotropic'' porcine coronavirus (pcv) and were compared with the effects of transmissible gastroenteritis virus (tgev) infection in five piglets. Virus localisation and lesions were studied in 14 oneweek-old piglets following combined intranasal-oral inoculation with a British isolate of ''pneumotropic'' porcine coronavirus (pcv) and were compared with the effects of transmissible gastroenteritis virus (TGEV) infection in five piglets. Following sterilisation of cages and isolators, a second batch of 12 piglets (Large White cross Landrace) aged seven days from two litters were inoculated with rev (five) or TGEV (five) or were uninoculated controls (two). Between two and six days after infection, acute changes were characterised by individual bronchiolar cells bulging into the lumen, ..; 00I''m Immunocytochemistry r-ev antigen was identified in the epithelial cytoplasm of small and medium bronchioles in eight of 14 piglets and its distribution was closely correlated with areas of pneumonia.

abstract:
  Virus localisation and lesions were studied in 14 one-week-old piglets following combined intranasal-oral inoculation with a British isolate of ‘pneumotropic’ porcine coronavirus (pcv) and were compared with the effects of transmissible gastroenteritis virus (tgev) infection in five piglets. Unlike TGEV-infected piglets, all pcv-inoculated piglets remained clinically healthy. Seroconversion was detected at seven days after inoculation. Mild bronchointerstitial pneumonia involving terminal airways was consistently present at two days after infection and thereafter. Both pcv and tgev infected bronchiolar epithelium and alveolar macrophages but, unlike tgev, replication by pcv in villous enterocytes was limited and did not cause villous atrophy.


id: cord-287266-sd5izamc
author: Song, Zhenhui
date: 2019-04-30
txt: ./txt/cord-287266-sd5izamc.txt
cache: ./cache/cord-287266-sd5izamc.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/30583231/
doi: 10.1016/j.rvsc.2018.12.005
summary:
  title: EIF4A2 interacts with the membrane protein of transmissible gastroenteritis coronavirus and plays a role in virus replication Using the GST pull-down approach and a CO-IP assay, the M protein was found to interact with porcine intestinal cells via eukaryotic translation initiation factor 4-alpha (EIF4A2), an essential component of the cellular translational machinery. The present study provides mechanistic insight into the interaction between the TGEV M protein and intestinal cells which contributes to the understanding of coronavirus replication and may be useful for the development of novel therapeutic strategies for TGEV infection. In the present study, using yeast two-hybrid screening, seven cellular proteins, including eukaryotic translation initiation factor 4-alpha (EIF4A2), were identified to be M-ligands. Moreover, previous reports have shown that EIF4A2 interacts with VP1 of infectious bursal disease virus (IBD) and inhibits the RNA polymerase activity of IBDV to reduce its replication in host cells (Tacken et al., 2004; Gao et al., 2017) .

title:
  EIF4A2 interacts with the membrane protein of transmissible gastroenteritis coronavirus and plays a role in virus replication

abstract:
  Abstract Transmissible gastroenteritis coronavirus (TGEV) is enteropathogenic coronavirus that causes diarrhea in pigs, and is associated with high morbidity and mortality in sucking piglets. The TGEV membrane (M) protein is a decisive protein for the proliferation of viral proteins, and is associated with virus assembly and budding. To identify the cellular proteins that interact with the TGEV M protein, yeast two-hybrid screening was employed, and seven cellular proteins were identified M-binding partners. Using the GST pull-down approach and a CO-IP assay, the M protein was found to interact with porcine intestinal cells via eukaryotic translation initiation factor 4-alpha (EIF4A2), an essential component of the cellular translational machinery. Additionally, confocal microscopy revealed that EIF4A2 and M were colocalized in the cytoplasm. Furthermore, the function of EIF4A2 in intestinal cells during TGEV infection was examined. A knockdown of EIF4A2 by siRNA markedly decreased M protein proliferation and TGEV replication in target cells. Thus demonstrating that EIF4A2 plays a significant role in TGEV replication. The present study provides mechanistic insight into the interaction between the TGEV M protein and intestinal cells which contributes to the understanding of coronavirus replication and may be useful for the development of novel therapeutic strategies for TGEV infection.


id: cord-287590-jjft3den
author: Rodák, L.
date: 2005-05-05
txt: ./txt/cord-287590-jjft3den.txt
cache: ./cache/cord-287590-jjft3den.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/15876221/
doi: 10.1111/j.1439-0450.2005.00829.x
summary:
  title: Use of Monoclonal Antibodies in Blocking ELISA Detection of Transmissible Gastroenteritis Virus in Faeces of Piglets Monoclonal antibodies (mAb) to the transmissible gastroenteritis virus (TGEV) nucleoprotein (N) and membrane protein (M) were prepared and used for the comparative assessment of three blocking ELISA variants to detect TGEV. Three variants of ELISA method with specificity checked by blocking test were compared by box titration using faeces of experimentally infected piglets 24 hpi. By the use of mAb D7/G7 alone or mixture of mAb in CB-ELISA examination of various TGEV strains (Table 1) or positive field faecal samples (results not shown) the same results were obtained. Therefore, the detection of TGEV in faecal samples by blocking ELISA method was the objective of our study. Competition ELISA, using monoclonal antibodies to the transmissible gastroenteritis virus (TGEV) S protein, for serologic differentiation of pigs infected with TGEV or porcine respiratory coronavirus

title:
  Use of Monoclonal Antibodies in Blocking ELISA Detection of Transmissible Gastroenteritis Virus in Faeces of Piglets

abstract:
  Monoclonal antibodies (mAb) to the transmissible gastroenteritis virus (TGEV) nucleoprotein (N) and membrane protein (M) were prepared and used for the comparative assessment of three blocking ELISA variants to detect TGEV. The competitive blocking ELISA format showed the highest sensitivity, allowing detection of 10(3) TCID(50) TGEV/ml in culture medium. Ninety‐nine porcine field faecal samples obtained from 37 herds affected with diarrhoea were examined, and various TGEV levels were found in nine samples from six herds. However, only in three samples were significant TGEV concentrations demonstrated. The relationship between incidence of TGEV gastroenteritis and the spread of porcine respiratory coronavirus infection in pig farms is discussed.


id: cord-287602-vda01gj6
author: Jin, Yu-Bei
date: 2018-07-18
txt: ./txt/cord-287602-vda01gj6.txt
cache: ./cache/cord-287602-vda01gj6.txt
extension: .txt
mime: text/plain
url: https://doi.org/10.1007/s00253-018-9205-0
doi: 10.1007/s00253-018-9205-0
summary:
  In this study, we constructed a suite of recombinant Lactobacillus plantarum with surface displaying the spike (S) protein coming from TGEV and fused with DC cells targeting peptides (DCpep) to develop an effective, safe, and convenient vaccine against transmissible gastroenteritis. Our research results found that the recombinant Lactobacillus plantarum (NC8-pSIP409-pgsA-S-DCpep) group expressing S fused with DCpep could not only significantly increase the percentages of MHC-II(+)CD80(+) B cells and CD3(+)CD4(+) T cells but also the number of IgA(+) B cells and CD3(+)CD4(+) T cells of ileum lamina propria, which elevated the specific secretory immunoglobulin A (SIgA) titers in feces and IgG titers in serum. Therefore, in this study, we mainly researched the effects of recombinant lactic acid bacteria NC8-pSIP409-pgsA-S-DCpep expressing DCpep and target antigen S protein on MHC-II + CD80 + B cells, CD3 + CD4 + cells related to mucosal immune responses, and anti-TGEVspecific antibodies.

title:
  Immune responses induced by recombinant Lactobacillus plantarum expressing the spike protein derived from transmissible gastroenteritis virus in piglets

abstract:
  Transmissible gastroenteritis coronavirus (TGEV) is one of the most severe threats to the swine industry. In this study, we constructed a suite of recombinant Lactobacillus plantarum with surface displaying the spike (S) protein coming from TGEV and fused with DC cells targeting peptides (DCpep) to develop an effective, safe, and convenient vaccine against transmissible gastroenteritis. Our research results found that the recombinant Lactobacillus plantarum (NC8-pSIP409-pgsA-S-DCpep) group expressing S fused with DCpep could not only significantly increase the percentages of MHC-II(+)CD80(+) B cells and CD3(+)CD4(+) T cells but also the number of IgA(+) B cells and CD3(+)CD4(+) T cells of ileum lamina propria, which elevated the specific secretory immunoglobulin A (SIgA) titers in feces and IgG titers in serum. Taken together, these results suggest that NC8-pSIP409-pgsA-S-DCpep expressing the S of TGEV fused with DCpep could effectively induce immune responses and provide a feasible original strategy and approach for the design of TGEV vaccines.


id: cord-288058-oilurica
author: Cui, Tingting
date: 2020-04-05
txt: ./txt/cord-288058-oilurica.txt
cache: ./cache/cord-288058-oilurica.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/32260595/
doi: 10.3390/v12040402
summary:
  To determine the effect of APN on coronavirus replication, the enterocytes were precultured with 1µg/mL hydrocortisone, 50 µM spermidine, 1 µg/mL insulin, 0.1 µM Wnt agonist, or 1% intestinal contents for 24 h prior to inoculation with PEDV CV777 Vero adapted strain, CV777 fecal suspension, and TGEV Miller. To determine the effect of APN on coronavirus replication, the enterocytes were precultured with 1µg/mL hydrocortisone, 50 µM spermidine, 1 µg/mL insulin, 0.1 µM Wnt agonist, or 1% intestinal contents for 24 h prior to inoculation with PEDV CV777 Vero adapted strain, CV777 fecal suspension, and TGEV Miller. The results show that pretreatment of primary enterocytes with hydrocortisone, spermidine, porcine insulin, Wnt agonist, and intestinal contents could stimulate the expression of APN and enhance the infection of PEDV CV777 Vero adapted and non-adapted strains and the TGEV Miller in the enterocytes.

title:
  Role of Porcine Aminopeptidase N and Sialic Acids in Porcine Coronavirus Infections in Primary Porcine Enterocytes

abstract:
  Porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus (TGEV) have been reported to use aminopeptidase N (APN) as a cellular receptor. Recently, the role of APN as a receptor for PEDV has been questioned. In our study, the role of APN in PEDV and TGEV infections was studied in primary porcine enterocytes. After seven days of cultivation, 89% of enterocytes presented microvilli and showed a two- to five-fold higher susceptibility to PEDV and TGEV. A significant increase of PEDV and TGEV infection was correlated with a higher expression of APN, which was indicative that APN plays an important role in porcine coronavirus infections. However, PEDV and TGEV infected both APN positive and negative enterocytes. PEDV and TGEV Miller showed a higher infectivity in APN positive cells than in APN negative cells. In contrast, TGEV Purdue replicated better in APN negative cells. These results show that an additional receptor exists, different from APN for porcine coronaviruses. Subsequently, treatment of enterocytes with neuraminidase (NA) had no effect on infection efficiency of TGEV, implying that terminal cellular sialic acids (SAs) are no receptor determinants for TGEV. Treatment of TGEV with NA significantly enhanced the infection which shows that TGEV is masked by SAs.


id: cord-290282-oxyzndsj
author: Ortego, Javier
date: 2003-03-30
url: https://www.ncbi.nlm.nih.gov/pubmed/12706086/
doi: 10.1016/s0042-6822(02)00096-x
title:
  Transmissible gastroenteritis coronavirus gene 7 is not essential but influences in vivo virus replication and virulence

abstract:
  Transmissible gastroenteritis coronavirus (TGEV) contains eight overlapping genes that are expressed from a 3′-coterminal nested set of leader-containing mRNAs. To facilitate the genetic manipulation of the viral genome, genes were separated by duplication of transcription regulating sequences (TRSs) and introduction of unique restriction endonuclease sites at the 5′ end of each gene using an infectious cDNA clone. The recombinant TGEV (rTGEV) replicated in cell culture with similar efficiency to the wild-type virus and stably maintained the modifications introduced into the genome. In contrast, the rTGEV replication level in the lungs and gut of infected piglets and virulence were significantly reduced. rTGEV in which gene 7 expression was abrogated (rTGEV-Δ7) were recovered from cDNA constructs, indicating that TGEV gene 7 was a nonessential gene for virus replication. Interestingly, in vivo infections with rTGEV-Δ7 showed an additional reduction in virus replication in the lung and gut, and in virulence, indicating that TGEV gene 7 influences virus pathogenesis.


id: cord-290640-kh2t0kfz
title: Downstream Ribosomal Entry for Translation of Coronavirus TGEV Gene 3b
author: O''Connor, Jennifer Black
date: 2000-03-30
txt: ./txt/cord-290640-kh2t0kfz.txt
cache: ./cache/cord-290640-kh2t0kfz.txt
extension: .txt
mime: text/plain
url: https://api.elsevier.com/content/article/pii/S0042682200902186
doi: 10.1006/viro.2000.0218
summary:
  Abstract Gene 3b (ORF 3b) in porcine transmissible gastroenteritis coronavirus (TGEV) encodes a putative nonstructural polypeptide of 27.7 kDa with unknown function that during translation in vitro is capable of becoming a glycosylated integral membrane protein of 31 kDa. In the virulent Miller strain of TGEV, ORF 3b is 5′-terminal on mRNA 3–1 and is presumably translated following 5′ cap-dependent ribosomal entry. Here we report that, whereas mRNA 3 has a sequence predicting leaky scanning for the translation of ORF 3b by the model of Kozak (1989) , experimental results with mutant constructs suggested downstream entry of ribosomes might also be used. To test by in vitro translation whether the 27.7-and 20-kDa gene 3b products (O''Connor and Brian, 1999) are synthesized when ORF 3b is positioned downstream of ORF 3a (beginning at base 337) on synthetic transcripts, uncapped transcripts of pORF3a-3b-4 DNA linearized at the BamHI site 50 nt downstream from the stop codon of gene 4 (Fig. 1C) were translated in either wheat germ extract or rabbit reticulocyte lysate.

abstract:
  Abstract Gene 3b (ORF 3b) in porcine transmissible gastroenteritis coronavirus (TGEV) encodes a putative nonstructural polypeptide of 27.7 kDa with unknown function that during translation in vitro is capable of becoming a glycosylated integral membrane protein of 31 kDa. In the virulent Miller strain of TGEV, ORF 3b is 5′-terminal on mRNA 3–1 and is presumably translated following 5′ cap-dependent ribosomal entry. For three other strains of TGEV, the virulent British FS772/70 and Taiwanese TFI and avirulent Purdue-116, mRNA species 3–1 is not made and ORF 3b is present as a non-overlapping second ORF on mRNA 3. ORF 3b begins at base 432 on mRNA 3 in Purdue strain. In vitro expression of ORF 3b from Purdue mRNA 3-like transcripts did not fully conform to a predicted leaky scanning pattern, suggesting ribosomes might also be entering internally. With mRNA 3-like transcripts modified to carry large ORFs upstream of ORF 3a, it was demonstrated that ribosomes can reach ORF 3b by entering at a distant downstream site in a manner resembling ribosomal shunting. Deletion analysis failed to identify a postulated internal ribosomal entry structure (IRES) within ORF 3a. The results indicate that an internal entry mechanism, possibly in conjunction with leaky scanning, is used for the expression of ORF 3b from TGEV mRNA 3. One possible consequence of this feature is that ORF 3b might also be expressed from mRNAs 1 and 2.


id: cord-290883-r2744fb3
author: TORRES, JUAN M.
date: 1995-11-30
txt: ./txt/cord-290883-r2744fb3.txt
cache: ./cache/cord-290883-r2744fb3.txt
extension: .txt
mime: text/plain
url: https://www.sciencedirect.com/science/article/pii/S0042682285700232
doi: 10.1006/viro.1995.0023
summary:
  The antisera induced in swine by the Ad5 recombinants expressing the amino-terminal 26% of the spike protein (containing sites C and B) or the full-length spike protein, when mixed with a lethal dose of virus prior to administration to susceptible piglets, delayed or completely prevented the induction of symptoms of disease, respectively. Alternatively, S gene ces are determined rather than titers since in the first fragments were removed from the original plasmid or procedure virus-antibody mixtures are evaluated in the from pSV2X3-TS vectors without SV-40 Pr signal, or withplaque assay without further dilution of the antibody, proout both Pr and polyadenylation sequences, using the viding highly reproducible results and information about restriction endonucleases indicated in Fig. 1 . Infectious Ad-TS recombinants expressing S protein fragments were generated by cotransfecting 293 cells with pFG144K3-TS or pAB14-TS (which carry S gene sequences from TGEV and pFG173 plasmids).

title:
  Induction of Antibodies Protecting against Transmissible Gastroenteritis Coronavirus (TGEV) by Recombinant Adenovirus Expressing TGEV Spike Protein

abstract:
  Abstract Ten recombinant adenoviruses expressing either fragments of 1135, 1587, or 3329 nt or the full-length spike gene of transmissible gastroenteritis coronavirus (TGEV) have been constructed. These recombinants produce S polypeptides with apparent molecular masses of 68, 86, 135, and 200 kDa, respectively. Expression of the recombinant antigen driven by Ad5 promoters was inhibited by the insertion of an exogenous SV-40 promoter. Most of the recombinant antigens remain intracytoplasmic in infected cells. All the recombinant-directed expression products contain functional antigenic sites C and B (Gebaueret al.,1991,Virology183, 225–238). The recombinant antigen of 135 kDa and that of 200 kDa, which represents the whole spike protein, also contain antigenic sites D and A, which have previously been shown to be the major inducers of TGEV-neutralizing antibodies. Interestingly, here we show that recombinant S protein fragments expressing only sites C and B also induced TGEV-neutralizing antibodies. The chimeric Ad5–TGEV recombinants elicited lactogenic immunity in hamsters, including the production of TGEV-neutralizing antibodies. The antisera induced in swine by the Ad5 recombinants expressing the amino-terminal 26% of the spike protein (containing sites C and B) or the full-length spike protein, when mixed with a lethal dose of virus prior to administration to susceptible piglets, delayed or completely prevented the induction of symptoms of disease, respectively.


id: cord-291192-wm2eyaam
title: Antigenic structures stably expressed by recombinant TGEV-derived vectors
author: Becares, Martina
date: 2014-08-09
txt: ./txt/cord-291192-wm2eyaam.txt
cache: ./cache/cord-291192-wm2eyaam.txt
extension: .txt
mime: text/plain
url: https://api.elsevier.com/content/article/pii/S0042682214003353
doi: 10.1016/j.virol.2014.07.027
summary:
  Transmissible gastroenteritis virus (TGEV) was engineered to express porcine reproductive and respiratory syndrome virus (PRRSV) small protein domains, as a strategy to improve heterologous gene stability. Recombinant TGEV (rTGEV) vectors have been engineered for dicistronic expression of heterologous genes, such as porcine reproductive and respiratory syndrome virus (PRRSV) GP5 and M proteins (Cruz et al., 2010) , or rotavirus VP2 and VP6, in which formation of rotavirus virus like particles (VLPs) in the cytoplasm of rTGEV infected cells was observed (Enjuanes et al., 2007) . Therefore, heterologous gene size reduction is a promising strategy to achieve stable expression in TGEV-derived vectors and in general in CoVs. This effect could be due to a decrease of the probability of non-homologous recombination in shorter sequences, or to the elimination of protein domains toxically affecting the host cell or rTGEV life cycle.

abstract:
  Coronaviruses (CoVs) are positive-stranded RNA viruses with potential as immunization vectors, expressing high levels of heterologous genes and eliciting both secretory and systemic immune responses. Nevertheless, its high recombination rate may result in the loss of the full-length foreign gene, limiting their use as vectors. Transmissible gastroenteritis virus (TGEV) was engineered to express porcine reproductive and respiratory syndrome virus (PRRSV) small protein domains, as a strategy to improve heterologous gene stability. After serial passage in tissue cultures, stable expression of small PRRSV protein antigenic domains was achieved. Therefore, size reduction of the heterologous genes inserted in CoV-derived vectors led to the stable expression of antigenic domains. Immunization of piglets with these TGEV vectors led to partial protection against a challenge with a virulent PRRSV strain, as immunized animals showed reduced clinical signs and lung damage. Further improvement of TGEV-derived vectors will require the engineering of vectors with decreased recombination rate.


id: cord-292019-rfu0bkag
author: Gómez, N.
date: 1998-09-30
txt: ./txt/cord-292019-rfu0bkag.txt
cache: ./cache/cord-292019-rfu0bkag.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/9791026/
doi: 10.1006/viro.1998.9315
summary:
  We report on the immunological response elicited by two recombinant versions of the glycoprotein S from the swine-transmissible gastroenteritis coronavirus (TGEV) expressed in transgenic plants. Arabidoposis plants were genetically transformed with cDNAs constructs encoding either the N-terminal domain (amino acid residues 1–750) or the full-length glycoprotein S of TGEV, responsible for the neutralizing antibody induction against the virus, under the control of the cauliflower mosaic virus 35S (CaMV 35S) promoter. Mice immunized with leaf extracts from transgenic plants developed antibodies that reacted specifically with TGEV in ELISA, immunoprecipitated the virus-induced protein, and neutralized the virus infectivity. In this report, we show that full-length or the globular part (N-terminal domain) of TGEV spike protein (glycoprotein S) expressed in transgenic plants retained the antigenic properties and elicited neutralizing antibodies when used to immunize animals.

title:
  Expression of Immunogenic Glycoprotein S Polypeptides from Transmissible Gastroenteritis Coronavirus in Transgenic Plants

abstract:
  Abstract The use of transgenic plants as vaccine production systems was described recently. We report on the immunological response elicited by two recombinant versions of the glycoprotein S from the swine-transmissible gastroenteritis coronavirus (TGEV) expressed in transgenic plants. Arabidoposis plants were genetically transformed with cDNAs constructs encoding either the N-terminal domain (amino acid residues 1–750) or the full-length glycoprotein S of TGEV, responsible for the neutralizing antibody induction against the virus, under the control of the cauliflower mosaic virus 35S (CaMV 35S) promoter. Genomic DNA and mRNA analyses of leaf extracts from transformed plants demonstrated the incorporation of the foreign cDNA into the arabidopsis genome, as well as their transcription. Expression of recombinant polypeptides were observed in most transgenic plants by ELISA using specific antibodies. Mice immunized with leaf extracts from transgenic plants developed antibodies that reacted specifically with TGEV in ELISA, immunoprecipitated the virus-induced protein, and neutralized the virus infectivity. From these results, we conclude that transgenic plants expressing glycoprotein S polypeptides may possibly be used as a source of recombinant antigen for vaccine production.


id: cord-293458-jb7u9xn6
title: Vaccines for porcine epidemic diarrhea virus and other swine coronaviruses
author: Gerdts, Volker
date: 2016-12-02
url: https://doi.org/10.1016/j.vetmic.2016.11.029
doi: 10.1016/j.vetmic.2016.11.029
abstract:
  The recent introduction of the porcine epidemic diarrhea virus (PEDV) into the North American swine herd has highlighted again the need for effective vaccines for swine coronaviruses. While vaccines for transmissible gastroenteritis virus (TGEV) have been available to producers around the world for a long time, effective vaccines for PEDV and deltacoronaviruses were only recently developed or are still in development. Here, we review existing vaccine technologies for swine coronaviruses and highlight promising technologies which may help to control these important viruses in the future.


id: cord-293945-gyb9mjb5
author: Chai, Weidong
date: 2012-11-28
txt: ./txt/cord-293945-gyb9mjb5.txt
cache: ./cache/cord-293945-gyb9mjb5.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/23188495/
doi: 10.1007/s00705-012-1543-0
summary:
  Virus yield reduction assay ST cell monolayers were infected with TGEV with or without probiotic bacteria treatment according to the experimental design. faecium (1.00E?07 CFU/ml) when the probiotic was added to the cells together with the virus during the infection period (competition assay). faecium inactivates TGEV particles by direct physical interaction with virus, a cell-free preincubation assay was performed. faecium together with the virus significantly increases mRNA expression levels of the pro-inflammatory cytokines interleukin 6 (IL-6) and IL-8 (an approximately 3-and 13-fold increase, respectively) when compared with TGEV-infected ST cells that had not been exposed to the probiotic (Fig. 6) . faecium (pretreatment), the viability of TGEV-infected cells was protected, and virus yields were reduced (Figs. In this study, the competition assay in which virus and probiotic bacteria are present in the culture medium side by side, exhibited the most pronounced antiviral activity in terms of cell survival (Figs.

title:
  Antiviral effects of a probiotic Enterococcus faecium strain against transmissible gastroenteritis coronavirus

abstract:
  The enteropathogenic coronavirus transmissible gastroenteritis virus (TGEV) causes severe disease in young piglets. We have studied the protective effects of the probiotic Enterococcus faecium NCIMB 10415 (E. faecium), which is approved as a feed additive in the European Union, against TGEV infection. E. faecium was added to swine testicle (ST) cells before, concomitantly with, or after TGEV infection. Viability assays revealed that E. faecium led to a dose-dependent rescue of viability of TGEV-infected cells reaching nearly to complete protection. Virus yields of the E. faecium–treated cultures were reduced by up to three log(10) units. Western blot analysis of purified TGEV revealed that the levels of all viral structural proteins were reduced after E. faecium treatment. Using transmission electron microscopy, we observed attachment of TGEV particles to the surface of E. faecium which might be a means to trap virus and to prevent infection. Increased production of nitric oxide in the cells treated with E. faecium and elevated expression of interleukin 6 and 8 pointed to stimulated cellular defense as a mechanism to fight TGEV infection.


id: cord-295967-mmgb7cxo
author: To, L. T.
date: 1992-12-31
txt: ./txt/cord-295967-mmgb7cxo.txt
cache: ./cache/cord-295967-mmgb7cxo.txt
extension: .txt
mime: text/plain
url: https://api.elsevier.com/content/article/pii/S0923251606801123
doi: 10.1016/s0923-2516(06)80112-3
summary:
  Summary Three strains of the transmissible gastroenteritis virus (TGEV) possessing different degrees of pathogenicity for piglets were examined for their capacity to express M and S glycoproteins on the infected cell surface using a microwell immunoperoxidase test. These two viral glycoproteins were easily detected on the plasma membrane of 0.1 % paraformaldehyde-fixed swine testis (ST) or pig kidney (RP.D) cells which were infected with high-passaged Purdue-115 and low-passaged D-52 strains and a high-passaged attenuated (188-SG) mutant of TGEV. Since the virulence of TGEV has been shown to decrease by serial passages in tissue culture, many authors have tried to differentiate the highpassaged (HP) attenuated strains from the lowpassaged (LP) virulent strain by in vitro markers, such as the level of the thermosensitivity of replication (Furuuchi et al., 1975; Hess and Bachman, 1976) , the resistance to digestive enzymes, low pH and temperature (Laude et al., 1981) , and by comparing viral replication and synthesis of structural antigens (Nguyen et al., 1987) .

title:
  Transmissible gastroenteritis coronavirus: surface antigens induced by virulent and attenuated strains

abstract:
  Summary Three strains of the transmissible gastroenteritis virus (TGEV) possessing different degrees of pathogenicity for piglets were examined for their capacity to express M and S glycoproteins on the infected cell surface using a microwell immunoperoxidase test. These two viral glycoproteins were easily detected on the plasma membrane of 0.1 % paraformaldehyde-fixed swine testis (ST) or pig kidney (RP.D) cells which were infected with high-passaged Purdue-115 and low-passaged D-52 strains and a high-passaged attenuated (188-SG) mutant of TGEV. No significant differences were found between attenuated and virulent strains with regard to the viral antigen expression on the membrane of infected cells over a 14-h period.


id: cord-296033-5zyoddl7
author: Hu, Xiaoliang
date: 2017-10-23
url: https://doi.org/10.1155/2017/7089091
doi: 10.1155/2017/7089091
title:
  Transmissible Gastroenteritis Virus Papain-Like Protease 1 Antagonizes Production of Interferon-β through Its Deubiquitinase Activity

abstract:
  Coronaviruses (CoVs), such as human coronavirus NL63 (HCoV-NL63), severe acute respiratory syndrome CoV (SARS-CoV), murine hepatitis virus (MHV), porcine epidemic diarrhea virus (PEDV), and Middle East Respiratory Syndrome Coronavirus (MERS-CoV), encode papain-like (PL) proteases that inhibit Sendai virus- (SeV-) induced interferon (IFN-β) production. Recently, the crystal structure of transmissible gastroenteritis virus (TGEV) PL1 has been solved, which was similar to that of SARS-CoV PL2(pro), which may antagonize host innate immunity. However, very little is known about whether TGEV PL1 can antagonize host innate immune response. Here, we presented evidence that TGEV PL1 encoded by the replicase gene could suppress the IFN-β expression and inhibit the nuclear translocation of interferon regulatory factor 3 (IRF3). The ability to antagonize IFN-β production was dependent on the intact catalytic activity of PL1. Furthermore, TGEV PL1 exerted deubiquitinase (DUB) activity which strongly inhibited the retinoic acid-induced gene I- (RIG-1-) and stimulator of interferon gene- (STING-) dependent IFN expression. Our data collectively suggest that TGEV PL1 can inhibit the IFN-β expression and interfere with RIG-1- and STING-mediated signaling through a viral DUB activity. Our study has yielded strong evidence for the TGEV PL1 mechanisms that counteract the host innate immunity.


id: cord-297398-40bshqly
author: Dong, Wanyu
date: 2019-11-18
url: https://doi.org/10.1016/j.antiviral.2019.104651
doi: 10.1016/j.antiviral.2019.104651
title:
  Receptor tyrosine kinase inhibitors block proliferation of TGEV mainly through p38 mitogen-activated protein kinase pathways

abstract:
  Emerging coronaviruses (CoVs) primarily cause severe gastroenteric or respiratory diseases in humans and animals, and no approved therapeutics are currently available. Here, A9, a receptor tyrosine kinase inhibitor (RTKI) of the tyrphostin class, is identified as a robust inhibitor of transmissible gastroenteritis virus (TGEV) infection in cell-based assays. Moreover, A9 exhibited potent antiviral activity against the replication of various CoVs, including murine hepatitis virus (MHV), porcine epidemic diarrhea virus (PEDV) and feline infectious peritonitis virus (FIPV). We further performed a comparative phosphoproteomic analysis to investigate the mechanism of action of A9 against TGEV infection in vitro. We specifically identified p38 and JNK1, which are the downstream molecules of receptor tyrosine kinases (RTKs) required for efficient TGEV replication, as A9 targets through plaque assays, qRT-PCR and Western blotting assays. p38 and JNK1 inhibitors and RNA interference further showed that the inhibitory activity of A9 against TGEV infection was mainly mediated by the p38 mitogen-activated protein kinase (MAPK) signaling pathway. All these findings indicated that the RTKI A9 directly inhibits TGEV replication and that its inhibitory activity against TGEV replication mainly occurs by targeting p38, which provides vital clues to the design of novel drugs against CoVs.


id: cord-298685-qxkxjxsz
title: Porcine epidemic diarrhea: A retrospect from Europe and matters of debate
author: Pensaert, Maurice B.
date: 2016-12-02
url: https://doi.org/10.1016/j.virusres.2016.05.030
doi: 10.1016/j.virusres.2016.05.030
abstract:
  Abstract A retrospect is given on the emergence of porcine epidemic diarrhea (PED) during the early seventies in Europe. While, at first, it appeared as a disease affecting feeder pigs, fattening- and adult swine, it later also became pathogenic for neonatal and suckling pigs hereby drastically increasing its economic impact. Isolation of the causative virus revealed a new porcine coronavirus, the origin of which has never been clarified. Pathogenesis studies with the prototype strain CV777 showed severe villous atrophy in neonatal pigs and the virus-animal interactions showed many similarities with transmissible gastro-enteritis virus (TGEV), another porcine coronavirus. Disease patterns in field outbreaks showed muchvariation but, while farm related factors played a role, possible genetic variations of virus strains in Europe have not been examined and are thus unknown. CV777 in experimental pigs caused diarrheal disease and mortality rates similar to those later encountered in Asia and more recently with the “original” US strains even though genomic typing of the prototype European strain have shown that it belongs to the S-INDEL strains. In Europe, PED has become endemic during the eighties and nineties and subsequently regressed so that, after 2000, swine populations in many countries have largely become seronegative. Sporadic outbreaks have recently reappeared showing a large variety of clinical outcomes.


id: cord-299189-59d4aojh
author: Zou, Hao
date: 2013-07-02
txt: ./txt/cord-299189-59d4aojh.txt
cache: ./cache/cord-299189-59d4aojh.txt
extension: .txt
mime: text/plain
url: https://www.sciencedirect.com/science/article/pii/S0166354213001721
doi: 10.1016/j.antiviral.2013.06.015
summary:
  title: Transmissible gastroenteritis virus: Identification of M protein-binding peptide ligands with antiviral and diagnostic potential In this study, the M protein of transmissible gastroenteritis virus (TGEV) was used to biopan a 12-mer phage display random peptide library. Plaque-reduction assays revealed that pepTGEV-M7 was able to prevent TGEV infection in vitro (p < 0.01) following pretreatment of the virus with the peptide. coli (Fig. 1) for use in biopanning the phage display library to identify peptides that bind the M protein of TGEV. Ten different TGEV-M protein-reactive phages were identified by ELISA, when rTGEV-M was used as the coating antigen (Fig. 2a) . 100TCID50 TGEV virus was pre-incubated with 2-fold, serially-diluted (500-31.25 lg/ml) peptide (pepTGEV-M7) then added to ST cells for 48 h. Bacterial expression of antigenic sites A and D in the spike protein of transmissible gastroenteritis virus and evaluation of their inhibitory effects on viral infection

title:
  Transmissible gastroenteritis virus: Identification of M protein-binding peptide ligands with antiviral and diagnostic potential

abstract:
  The membrane (M) protein is one of the major structural proteins of coronavirus particles. In this study, the M protein of transmissible gastroenteritis virus (TGEV) was used to biopan a 12-mer phage display random peptide library. Three phages expressing TGEV-M-binding peptides were identified and characterized in more depth. A phage-based immunosorbent assay (phage-ELISA) capable of differentiating TGEV from other coronaviruses was developed using one phage, phTGEV-M7, as antigen. When the phage-ELISA was compared to conventional antibody-based ELISA for detecting infections, phage-ELISA exhibited greater sensitivity. A chemically synthesized, TGEV-M7 peptide (pepTGEV-M7; HALTPIKYIPPG) was evaluated for antiviral activity. Plaque-reduction assays revealed that pepTGEV-M7 was able to prevent TGEV infection in vitro (p < 0.01) following pretreatment of the virus with the peptide. Indirect immunofluorescence and real-time RT-PCR confirmed the inhibitory effects of the peptide. These results indicate that pepTGEV-M7 might be utilized for virus-specific diagnostics and treatment.


id: cord-300436-beb8k075
author: Zhang, Shuai
date: 2018-10-20
url: https://doi.org/10.1186/s12964-018-0283-5
doi: 10.1186/s12964-018-0283-5
title:
  Transferrin receptor 1 is a supplementary receptor that assists transmissible gastroenteritis virus entry into porcine intestinal epithelium

abstract:
  BACKGROUND: Transmissible gastroenteritis virus (TGEV), the etiologic agent of transmissible gastroenteritis, infects swine of all ages causing vomiting and diarrhea, in newborn piglets the mortality rate is near 100%. Intestinal epithelial cells are the primary target cells of TGEV. Transferrin receptor 1 (TfR1), which is highly expressed in piglets with anemia, may play a role in TGEV infection. However, the underlying mechanism of TGEV invasion remains largely unknown. RESULTS: Our study investigated the possibility that TfR1 can serve as a receptor for TGEV infection and enables the invasion and replication of TGEV. We observed that TGEV infection promoted TfR1 internalization, clustering, and co-localization with TfR1 early in infection, while TfR1 expression was significantly down-regulated as TGEV infection proceeded. TGEV infection and replication were inhibited by occluding TfR1 with antibodies or by decreasing TfR1 expression. TGEV infection increased in TGEV-susceptible ST or IPEC-J2 cell lines and TGEV-resistant Caco-2 cells when porcine TfR1 was over-expressed. Finally, we found that the TGEV S1 protein interacts with the extracellular region of TfR1, and that pre-incubating TGEV with a protein fragment containing the extracellular region of TfR1 blocked viral infection. CONCLUSIONS: Our results support the hypothesis that TfR1 is an additional receptor for TGEV and assists TGEV invasion and replication. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12964-018-0283-5) contains supplementary material, which is available to authorized users.


id: cord-302306-fudeixy2
author: Xu, Kui
date: 2020-09-02
url: https://doi.org/10.7554/elife.57132
doi: 10.7554/elife.57132
title:
  CD163 and pAPN double-knockout pigs are resistant to PRRSV and TGEV and exhibit decreased susceptibility to PDCoV while maintaining normal production performance

abstract:
  Porcine reproductive and respiratory syndrome virus (PRRSV) and transmissible gastroenteritis virus (TGEV) are two highly infectious and lethal viruses causing major economic losses to pig production. Here, we report generation of double-gene-knockout (DKO) pigs harboring edited knockout alleles for known receptor proteins CD163 and pAPN and show that DKO pigs are completely resistant to genotype 2 PRRSV and TGEV. We found no differences in meat-production or reproductive-performance traits between wild-type and DKO pigs, but detected increased iron in DKO muscle. Additional infection challenge experiments showed that DKO pigs exhibited decreased susceptibility to porcine deltacoronavirus (PDCoV), thus offering unprecedented in vivo evidence of pAPN as one of PDCoV receptors. Beyond showing that multiple gene edits can be combined in a livestock animal to achieve simultaneous resistance to two major viruses, our study introduces a valuable model for investigating infection mechanisms of porcine pathogenic viruses that exploit pAPN or CD163 for entry.


id: cord-302503-7s9f8wje
title: Rapid and efficient detection methods of pathogenic swine enteric coronaviruses
author: Fu, Yuguang
date: 2020-05-19
url: https://doi.org/10.1007/s00253-020-10645-5
doi: 10.1007/s00253-020-10645-5
abstract:
  ABSTRACT: Porcine enteric coronaviruses (CoVs) cause highly contagious enteric diarrhea in suckling piglets. These COV infections are characterized by clinical signs of vomiting, watery diarrhea, dehydration, and high morbidity and mortality, resulting in significant economic losses and tremendous threats to the pig farming industry worldwide. Because the clinical manifestations of pigs infected by different CoVs are similar, it is difficult to differentiate between the specific pathogens. Effective high-throughput detection methods are powerful tools used in the prevention and control of diseases. The immune system of piglets is not well developed, so serological methods to detect antibodies against these viruses are not suitable for rapid and early detection. This paper reviews various PCR-based methods used for the rapid and efficient detection of these pathogenic CoVs in swine intestines. KEY POINTS: 1. Swine enteric coronaviruses (CoVs) emerged and reemerged in past years. 2. Enteric CoVs infect pigs at all ages with high mortality rate in suckling pigs. 3. Rapid and efficient detection methods are needed and critical for diagnosis.


id: cord-304014-k62mtr9j
author: Ma, Xuelian
date: 2019-11-04
url: https://www.ncbi.nlm.nih.gov/pubmed/31684870/
doi: 10.1186/s12864-019-6156-5
title:
  Identification and analysis of long non-coding RNAs that are involved in inflammatory process in response to transmissible gastroenteritis virus infection

abstract:
  BACKGROUND: Transmissible gastroenteritis virus (TGEV) infection can cause acute inflammation. Long noncoding RNAs (lncRNAs) play important roles in a number of biological process including inflammation response. However, whether lncRNAs participate in TGEV-induced inflammation in porcine intestinal epithelial cells (IPECs) is largely unknown. RESULTS: In this study, the next-generation sequencing (NGS) technology was used to analyze the profiles of lncRNAs in Mock and TGEV-infected porcine intestinal epithelial cell-jejunum 2 (IPEC-J2) cell line. A total of 106 lncRNAs were differentially expressed. Many differentially expressed lncRNAs act as elements to competitively attach microRNAs (miRNAs) which target to messenger RNA (mRNAs) to mediate expression of genes that related to toll-like receptors (TLRs), NOD-like receptors (NLRs), tumor necrosis factor (TNF), and RIG-I-like receptors (RLRs) pathways. Functional analysis of the binding proteins and the up/down-stream genes of the differentially expressed lncRNAs revealed that lncRNAs were principally related to inflammatory response. Meanwhile, we found that the differentially expressed lncRNA TCONS_00058367 might lead to a reduction of phosphorylation of transcription factor p65 (p-p65) in TGEV-infected IPEC-J2 cells by negatively regulating its antisense gene promyelocytic leukemia (PML). CONCLUSIONS: The data showed that differentially expressed lncRNAs might be involved in inflammatory response induced by TGEV through acting as miRNA sponges, regulating their up/down-stream genes, or directly binding proteins.


id: cord-309433-wm0k13qh
author: Paton, D. J.
date: 1991-08-31
txt: ./txt/cord-309433-wm0k13qh.txt
cache: ./cache/cord-309433-wm0k13qh.txt
extension: .txt
mime: text/plain
url: https://www.sciencedirect.com/science/article/pii/000719359190010K
doi: 10.1016/0007-1935(91)90010-k
summary:
  Abstract A competition ELISA utilizing a mAb directed towards a peplomer protein epitope common to TGEV, PRCV and related feline and canine coronaviruses is described. Serological differentiation between TGEV and PRCV is now possible using competition ELISAs and monoclonal antibodies (mAbs) to TGEV-specific epitopes (Callebaut el al., 1989 , van Nieuwstadt & Boonstra, 1990 . This communication describes a competition ELISA utilizing a mAb (6A .C3) directed towards a peplomer protein epitope common to TGEV, PRCV, and a number of related feline and canine coronaviruses, but not to other porcine coronaviruses (Sanchez et al., 1990) . VNT positive sera from field cases (n=167) and from pigs experimentally infected with TGEV or PRCV (n=35) all scored positive in ELISA (values : 1-49%) . A recent serological survey of British pigs by TGEV-specific ELISA indicated a seroprevalence of only 0 .6% (Brown & Paton, 1991) , suggesting that most TGEV/PRCV antibody positive samples reflect PRCV infection and that such infections remain common .

title:
  An ELISA for the detection of serum antibodies to both transmissible gastroenteritis virus and porcine respiratory coronavirus

abstract:
  Abstract A competition ELISA utilizing a mAb directed towards a peplomer protein epitope common to TGEV, PRCV and related feline and canine coronaviruses is described.


id: cord-309446-j0suk34b
author: Wesley, Ronald D.
date: 1993-12-31
url: https://www.sciencedirect.com/science/article/pii/037811359390073G
doi: 10.1016/0378-1135(93)90073-g
title:
  Immunization of pregnant gilts with PRCV induces lactogenic immunity for protection of nursing piglets from challenge with TGEV

abstract:
  Abstract The level of passive protection against transmissible gastroenteritis virus (TGEV) was evaluated by experimentally infecting 12 pregnant gilts with different doses of porcine respiratory coronavirus (PRCV) and challenging their litters at 4 days of age. An overall survival rate of 70% was found for piglets nursing the 12 PRCV-infected gilts, compared to a 16% survival rate for piglets of nine uninfected control gilts. Six of the PRCV-infected gilts had adequate levels of immunity to resist infection with TGEV following the challenge of their litters. These six completely immuned gilts also solidly protected their litters from TGEV as shown by a 96% piglet survival rate through weaning at 3 weeks of age. The results suggest that respiratory infection with PRCV induces a substantial degree of protective lactogenic immunity against TGEV.


id: cord-309693-f2htekhz
author: Yu, Meiling
date: 2017-09-25
txt: ./txt/cord-309693-f2htekhz.txt
cache: ./cache/cord-309693-f2htekhz.txt
extension: .txt
mime: text/plain
url: https://doi.org/10.3390/v9100274
doi: 10.3390/v9100274
summary:
  To develop an effective bivalent oral vaccine against TGEV and PEDV infection, the D antigenic site of the TGEV spike (S) protein and the major antigen site (core neutralizing epitope—COE) of the PEDV S protein were used as immunogens, and the enhanced green fluorescent protein (eGFP) gene was used as a reporter to construct genetically engineered Lactobacillus casei rLpPG(F)-T7g10-eGFP-6D-COE. The results showed that levels of anti-PEDV and anti-TGEV serum immunoglobulin G (IgG) and mucosal secreted immunoglobulin A (sIgA) antibodies obtained from the mice immunized with rLpPG(F)-T7g10-eGFP-6D-COE, as well as the proliferation levels of lymphocytes, were significantly higher than those in mice orally administered phosphate-buffered saline (PBS) or rLpPG-T7g10. This was evidenced by significantly higher levels of virus-neutralizing antibodies, anti-PEDV/TGEV serum IgG, and mucosal sIgA in mice orally immunized with rLpPG F -T7g10-eGFP-6D-COE, compared to the levels for the rLpPG-T7g10 or PBS groups.

title:
  Immunogenicity of eGFP-Marked Recombinant Lactobacillus casei against Transmissible Gastroenteritis Virus and Porcine Epidemic Diarrhea Virus

abstract:
  Porcine transmissible gastroenteritis virus (TGEV) and porcine epidemic diarrhea virus (PEDV) are the causative agents of highly fatal acute diarrhea in pigs, resulting in enormous losses in the pig industry worldwide. To develop an effective bivalent oral vaccine against TGEV and PEDV infection, the D antigenic site of the TGEV spike (S) protein and the major antigen site (core neutralizing epitope—COE) of the PEDV S protein were used as immunogens, and the enhanced green fluorescent protein (eGFP) gene was used as a reporter to construct genetically engineered Lactobacillus casei rLpPG(F)-T7g10-eGFP-6D-COE. The expression of proteins of interest by the recombinant L. casei was confirmed by confocal laser scanning microscopy and a Western blot assay, and the immunogenicity of rLpPG(F)-T7g10-eGFP-6D-COE in orally immunized mice was evaluated. The results showed that levels of anti-PEDV and anti-TGEV serum immunoglobulin G (IgG) and mucosal secreted immunoglobulin A (sIgA) antibodies obtained from the mice immunized with rLpPG(F)-T7g10-eGFP-6D-COE, as well as the proliferation levels of lymphocytes, were significantly higher than those in mice orally administered phosphate-buffered saline (PBS) or rLpPG-T7g10. Moreover, the serum IgG antibodies showed neutralizing effects against PEDV and TGEV. Our data suggest that the antibiotic resistance-free genetically engineered L. casei bivalent oral vaccine provides a safe and promising strategy for vaccine development against PEDV and TGEV.


id: cord-310467-v2wlu5eq
author: Tô, Long-Thành
date: 1992-10-02
url: https://www.sciencedirect.com/science/article/pii/002217599290192V
doi: 10.1016/0022-1759(92)90192-v
title:
  Effect of fixation on the detection of transmissible gastroenteritis coronavirus antigens by the fixed-cell immunoperoxidase technique

abstract:
  Abstract The effect of various fixatives and detergents on the in vitro detection of the viral determinants which are expressed in swine testis cells infected with the transmissible gastroenteritis coronavirus (TGEV) was studied using a microwell immunoperoxidase technique. When compared with glutaraldehyde and formaldehyde, 0.1% paraformaldehyde was found to be the fixative of choice for the detection of these determinants on the membranes of infected cells. Among dehydrating fixatives, 80% acetone or a mixture of acetone and ethanol or of acetone, methanol and ethanol were found to be the best fixatives for the detection of these viral determinants which are expressed in infected cells. In the case of acetone, the temperature of fixation and its concentration in the fixative preparation were found to be important. The treatment of 0.05% glutaraldehyde-fixed, infected cells with 0.1% saponin or 0.1% paraformaldehyde-fixed, infected cells with 1%NP-40 led to satisfactory detection of viral determinants. Using Triton X-100 to render cells permeable, the quantities of N and M antigen detected in TGEV-infected cells prefixed with either 0.05% glutaraldehyde or 0.1% paraformaldehyde were equal to those of 80% acetone-fixed, TGEV-infected cells while the quantity of S antigen detected was diminished. The effect of other detergents such as zwittergent, embigen BB, Chaps and N-lauroylsarcosine on the detection of viral determinants was also studied.


id: cord-312210-3x9s3g8n
author: Stoian, Ana
date: 2019-12-24
url: https://api.elsevier.com/content/article/pii/S0042682219303496
doi: 10.1016/j.virol.2019.12.007
title:
  The use of cells from ANPEP knockout pigs to evaluate the role of aminopeptidase N (APN) as a receptor for porcine deltacoronavirus (PDCoV)

abstract:
  The coronaviruses, porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV), and porcine deltacoronavirus (PDCoV) represent important sources of neonatal diarrhea on pig farms. The requirement for aminopeptidase N (APN) as a receptor for TGEV, but not for PEDV, is well established. In this study, the biological relevance of APN as a receptor for PDCoV was tested by using CRISPR/Cas9 to knockout the APN gene, ANPEP, in pigs. Porcine alveolar macrophages (PAMs) from ANPEP knockout (KO) pigs showed resistance to PDCoV infection. However, lung fibroblast-like cells, derived from the ANPEP KO PAM cultures, supported PDCoV infection to high levels. The results suggest that APN is a receptor for PDCoV in PAMs but is not necessary for infection of lung-derived fibroblast cells. The infection of the ANPEP KO pigs with PDCoV further confirmed that APN is dispensable as a receptor for PDCoV.


id: cord-313126-7hrjzapj
author: Chen, Fangzhou
date: 2019-03-08
url: https://www.ncbi.nlm.nih.gov/pubmed/30850666/
doi: 10.1038/s41598-019-40564-z
title:
  Decline of transmissible gastroenteritis virus and its complex evolutionary relationship with porcine respiratory coronavirus in the United States

abstract:
  The epidemiology and genetic diversity of transmissible gastroenteritis virus (TGEV) in the United States (US) was investigated by testing clinical cases for TGEV by real time RT-PCR between January 2008 and November 2016. Prevalence of TGEV ranged between 3.8–6.8% and peaked during cold months until March 2013, in which prevalence decreased to < 0.1%. Nineteen complete TGEV genomes and a single strain of porcine respiratory coronavirus (PRCV) from the US were generated and compared to historical strains to investigate the evolution of these endemic coronaviruses. Sixteen of our TGEV strains share 8 unique deletions and 119 distinct amino acid changes, which might greatly affect the biological characteristics of the variant TGEV, and resulted in a “variant” genotype of TGEV. The “variant” genotype shared similar unique deletions and amino acid changes with the recent PRCV strain identified in this study, suggesting a recombination event occurred between the ‘‘variant’’ TGEV and PRCV. Moreover, the results indicate the “variant” genotype is the dominant genotype circulating in the US. Therefore, this study provides insight into the occurrence, origin, genetic characteristics, and evolution of TGEV and PRCV circulating in the US.


id: cord-315688-ba5dus2j
author: He, Lei
date: 2012-08-28
url: https://www.ncbi.nlm.nih.gov/pubmed/22929207/
doi: 10.1186/1743-422x-9-176
title:
  In vitro inhibition of transmissible gastroenteritis coronavirus replication in swine testicular cells by short hairpin RNAs targeting the ORF 7 gene

abstract:
  BACKGROUND: Transmissible gastroenteritis (TGE) is a highly contagious viral disease of swine, characterized by severe vomiting, diarrhea, and high mortality. Currently, the vaccines for it are only partially effective and no specific drug is available for treatment of TGE virus (TGEV) infection. RNA interference has been confirmed as a new approach for controlling viral infections. In this study, the inhibitory effect of short hairpin RNAs (shRNAs) targeting the ORF 7 gene of TGEV on virus replication was examined. RESULTS: Four theoretically effective sequences of TGEV ORF 7 gene were designed and selected for construction of shRNA expression plasmids. In the reporter assays, three of four shRNA expression plasmids were able to inhibit significantly the expression of ORF 7 gene and replication of TGEV, as shown by real-time quantitative RT-PCR analysis of viral ORF 7 and N genes and detection of virus titers (TCID(50)/ml). Stable swine testicular (ST) cells expressing the shRNAs were established. Observation of the cytopathic effect and apoptosis, as well as a cell proliferation assay demonstrated that the three shRNAs were capable of protecting ST cells against TGEV destruction, with high specificity and efficiency. CONCLUSIONS: Our results indicated that plasmid-transcribed shRNAs targeting the ORF 7 gene in the TGEV genome effectively inhibited expression of the viral target gene and viral replication in vitro. These findings provide evidence that the shRNAs have potential therapeutic application for treatment of TGE.


id: cord-315780-uhi66unn
author: Paton, David
date: 1997-07-31
txt: ./txt/cord-315780-uhi66unn.txt
cache: ./cache/cord-315780-uhi66unn.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/9255741/
doi: 10.1016/s0166-0934(97)00055-4
summary:
  Abstract An RT-PCR method was developed that amplified genetic material from the 5′ end of the S protein gene of both transmissible gastroenteritis virus (TGEV) and porcine respiratory coronavirus (PRCV), but discriminated between the two by the size of the product generated. Detection of TGEV in clinical specimens was possible using a spin column method to extract RNA and sensitivity was compared to virus isolation and antigen detection ELISA. There are also reports of the use of DNA probes and of RT-PCR as detectors of TGEV RNA (Bae et al., 1991; Vaughn et al., 1996; Wesley et al., 1991; Jackwood et al., 1995) but the methods were not shown to be suitable for the direct detection of virus in clinical samples. Differentiation of transmissible gastroenteritis virus from porcine respiratory coronavirus and other antigenically related coronaviruses by using cDNA probes specific for the 5'' region of the S glycoprotein gene

title:
  Detection of transmissible gastroenteritis virus by RT-PCR and differentiation from porcine respiratory coronavirus

abstract:
  Abstract An RT-PCR method was developed that amplified genetic material from the 5′ end of the S protein gene of both transmissible gastroenteritis virus (TGEV) and porcine respiratory coronavirus (PRCV), but discriminated between the two by the size of the product generated. A number of restriction endonuclease enzymes were assessed for recognition of the amplicons so produced. The assay was shown to detect viral RNA from all of the 26 different TGEV and PRCV isolates examined, covering a period from 1946 to 1996. Detection of TGEV in clinical specimens was possible using a spin column method to extract RNA and sensitivity was compared to virus isolation and antigen detection ELISA. The method could provide a means of confirming positive results from immunological screening tests such as FAT and ELISA, reducing the need for virus isolation and convalescent serology.


id: cord-316134-lkd2mj27
author: Sungsuwan, Suttipun
date: 2020-01-15
txt: ./txt/cord-316134-lkd2mj27.txt
cache: ./cache/cord-316134-lkd2mj27.txt
extension: .txt
mime: text/plain
url: https://www.sciencedirect.com/science/article/pii/S0042682219303150
doi: 10.1016/j.virol.2019.11.007
summary:
  Investigation of possible molecular interactions between components of PEDV, PDCoV and TGEV and their influence on replication of each virus would provide a crucial insight into comprehensive understanding of these CoVs. Of all viral proteins, we have chosen to start with the N protein, as it is among the most abundant and ubiquitous structural proteins in infected cells. For viral infection in the transient CoV N expression experiment, VeroE6 cells were transfected with 1 or 2 μg of pCAGGS-PEDV N-Myc, pCAGGS-PDCoV N-HA, pCAGGS-TGEV N-FLAG, or the empty pCAGGS vector and were incubated for 24 h to allow for protein expression. To investigate how this protein-protein interaction might affect PEDV replication, we transiently transfected VeroE6 cells with varying amounts of the pCAGGS plasmid expressing N proteins from either PDCoV or TGEV for 24 h before infection with PEDV-mCherry (MOI = 0.0001) and followed the course of viral replication for each condition.

title:
  Nucleocapsid proteins from other swine enteric coronaviruses differentially modulate PEDV replication

abstract:
  Porcine epidemic diarrhea virus (PEDV), transmissible gastroenteritis virus (TGEV) and porcine deltacoronavirus (PDCoV) share tropism for swine intestinal epithelial cells. Whether mixing of viral components during co-infection alters pathogenic outcomes or viral replication is not known. In this study, we investigated how different coronavirus nucleocapsid (CoV N) proteins interact and affect PEDV replication. We found that PDCoV N and TGEV N can competitively interact with PEDV N. However, the presence of PDCoV or TGEV N led to very different outcomes on PEDV replication. While PDCoV N significantly suppresses PEDV replication, overexpression of TGEV N, like that of PEDV N, increases production of PEDV RNA and virions. Despite partial interchangeability in nucleocapsid oligomerization and viral RNA synthesis, endogenous PEDV N cannot be replaced in the production of infectious PEDV particles. Results from this study give insights into functional compatibilities and evolutionary relationship between CoV viral proteins during viral co-infection and co-evolution.


id: cord-317462-nvrl0vyi
author: Song, Zhenhui
date: 2016-09-28
url: https://doi.org/10.1016/j.jviromet.2016.09.018
doi: 10.1016/j.jviromet.2016.09.018
title:
  Morphogenesis and proliferative rule of porcine transmissible gastroenteritis virus in porcine intestinal epithelial cells

abstract:
  To gain a better understanding of the replication, proliferation and infection characteristics of porcine transmissible gastroenteritis virus (TGEV) in porcine intestinal epithelial cells (IECs), this study established a cell model of IECs infected with the Chongqing (CQ) strain of TGEV. The morphogenesis and proliferative rule of TGEV in porcine IECs were investigated using transmission electron microscopy, indirect immunofluorescence assays and real-time fluorescence quantitative PCR. Observations under the TEM indicated that the enveloped viral particles were roughly spherical, with diameters of between 80 and 120 nm. The virions entered porcine IECs by membrane fusion and the mature viruses in the vacuoles were transported to the cell membrane before release. The results also showed that from 0 to 12 h after TGEV infection of porcine IECs, the intracellular viral RNA content did not change significantly. Logarithmic growth occurred from 12 to 36 h, after which it gradually decreased. Moreover, the extracellular RNA content began to rise at 24 h after inoculation and then reduced gradually at approximately 48 h. This study provided a theoretical foundation for further study on the infection characteristics of TGEV in target cells.


id: cord-317496-6o2upns3
author: Pascual-Iglesias, Alejandro
date: 2019-07-25
url: https://www.ncbi.nlm.nih.gov/pubmed/31349683/
doi: 10.3390/v11080682
title:
  Recombinant Chimeric Transmissible Gastroenteritis Virus (TGEV)—Porcine Epidemic Diarrhea Virus (PEDV) Virus Provides Protection against Virulent PEDV

abstract:
  Porcine epidemic diarrhea virus (PEDV) is an enteric coronavirus causing high morbidity and mortality in porcine herds worldwide. Although both inactivated and live attenuated vaccines have been extensively used, the emergence of highly virulent strains and the recurrent outbreaks even in vaccinated farms highlight the need of effective vaccines. Engineering of genetically defined live attenuated vaccines is a rational approach for novel vaccine development. In this line, we engineered an attenuated virus based on the transmissible gastroenteritis virus (TGEV) genome, expressing a chimeric spike protein from a virulent United States (US) PEDV strain. This virus (rTGEV-RS-SPEDV) was attenuated in highly-sensitive five-day-old piglets, as infected animals did not lose weight and none of them died. In addition, the virus caused very minor tissue damage compared with a virulent virus. The rTGEV-RS-SPEDV vaccine candidate was also attenuated in three-week-old animals that were used to evaluate the protection conferred by this virus, compared with the protection induced by infection with a virulent PEDV US strain (PEDV-NVSL). The rTGEV-RS-SPEDV virus protected against challenge with a virulent PEDV strain, reducing challenge virus titers in jejunum and leading to undetectable challenge virus RNA levels in feces. The rTGEV-RS-SPEDV virus induced a humoral immune response specific for PEDV, including neutralizing antibodies. Altogether, the data indicated that rTGEV-RS-SPEDV is a promising vaccine candidate against virulent PEDV infection.


id: cord-322238-8iwljdoi
author: Chen, Qin
date: 2010-08-29
url: https://www.ncbi.nlm.nih.gov/pubmed/20799985/
doi: 10.1186/1743-422x-7-206
title:
  Detection of swine transmissible gastroenteritis coronavirus using loop-mediated isothermal amplification

abstract:
  A conserved nucleic acid fragment of the nucleocapsid gene of Swine Transmissible Gastroenteritis Coronavirus (TGEV) was chosen as the target, six special primers were designed successfully. Loop-mediated isothermal amplification (LAMP) was developed to detect the TGEV by incubation at 60°C for 1 h and the product specificity was confirmed by HphI digestion. Standard curves with high accuracy for TGEV quantization was constructed by adding 1 × SYBR greenI in the LAMP reaction. The assay established in this study was found to detect only the TGEV and no cross-reaction with other viruses, demonstrating its high specificity. By using serial sample dilutions as templates, the detection limit of LAMP was about 10 pg RNA, 10 times more sensitive than that of PCR and could be comparable to the nest-PCR.


id: cord-324098-9x18bidq
title: p53- and ROS-mediated AIF pathway involved in TGEV-induced apoptosis
author: DING, Li
date: 2018-09-25
url: https://www.ncbi.nlm.nih.gov/pubmed/30249935/
doi: 10.1292/jvms.18-0104
abstract:
  We previously demonstrated that transmissible gastroenteritis virus (TGEV) could induce apoptosis through caspase signaling. However, apoptosis was not completely prevented by caspases inhibitors, suggesting that there may be a caspase-independent pathway involved in TGEV-induced cell apoptosis. In this study, we investigated the regulation of apoptosis-inducing factor (AIF) on TGEV-induced apoptotic pathway. Results indicated that AIF translocated from the mitochondria to nucleus during TGEV infection, and the AIF inhibitor, N-phenylmaleimide (NP), significantly attenuated the apoptosis. In addition, the translocation of AIF was inhibited by Veliparib (ABT-888), an inhibitor of poly (ADP-ribose) polymerase (PARP). And the reactive oxygen species (ROS) scavenger, pyrrolidinedithiocarbamic (PDTC), redistributed AIF in the mitochondria and nucleus in TGEV-infected cells. Moreover, the protein levels in nucleus and the mRNA levels of AIF were inhibited in the presence of the p53 inhibitor, piﬁthrin-α (PFT-α) or in TGEV-infected p53−/−cells. Furthermore, TGEV-induced apoptosis was blocked by combination of three or more inhibitors, such as pan caspase inhibitor Z-VAD-FMK, NP, ABT-888, PDTC, PFT-α, to treat PK-15 cells. Taken together, these results suggest that the p53- and ROS-mediated AIF pathway and caspase-dependent pathway were involved in TGEV-induced apoptosis.


id: cord-326349-59566vqe
author: Ding, Li
date: 2013-12-26
url: https://www.sciencedirect.com/science/article/pii/S0168170213003286
doi: 10.1016/j.virusres.2013.09.036
title:
  Transmissible gastroenteritis virus infection induces cell cycle arrest at S and G2/M phases via p53-dependent pathway

abstract:
  p53 signaling pathway plays an important role in the regulation of cell cycle. Our previous studies have demonstrated that TGEV infection induces the activation of p53 signaling pathway. In this study we investigated the effects of TGEV infection on the cell cycle of host cells and the roles of p53 activation in this process. The results showed that TGEV infection induced cell cycle arrest at S and G2/M phases in both asynchronous and synchronized PK-15 and ST cells, while UV-inactivated TGEV lost the ability of induction of cell cycle arrest. TGEV infection promoted p21 accumulation, down-regulated cell cycle-regulatory proteins cyclins B1, cdc2, cdk2 and PCNA. Further studies showed that inhibition of p53 signaling could attenuate the TGEV-induced S- and G2/M-phase arrest by reversing the expression of p21 and corresponding cyclin/cdk. In addition, TGEV infection of the cells synchronized in various stages of cell cycle showed that viral genomic RNA and subgenomic RNA, and virus titer were higher in the cells released from S-phase- or G2/M phase-synchronized cells than that in the cells released from the G0/G1 phase-synchronized or asynchronous cells after 18 h p.i. Taken together, our data suggested that TGEV infection induced S and G2/M phase arrest in host cells, which might provide a favorable condition for viral replication.


id: cord-326719-p1ma4akz
title: Virus-based vectors for gene expression in mammalian cells: Coronavirus
author: Enjuanes, Luis
date: 2003-12-31
url: https://www.sciencedirect.com/science/article/pii/S016773060338010X
doi: 10.1016/s0167-7306(03)38010-x
abstract:
  Publisher Summary The coronavirus and the torovirus genera form the Coronaviridae family, which is closely related to the Arteriviridae family. Both families are included in the Nidovirales order. Recently, a new group of invertebrate viruses, the Roniviridae, with a genetic structure and replication strategy similar to those of coronaviruses, has been described. This new virus family has been included within the Nidovirales. Coronaviruses have several advantages as vectors over other viral expression systems: (1) coronaviruses are single-stranded RNA viruses that replicate within the cytoplasm without a DNA intermediary, making integration of the virus genome into the host cell chromosome unlikely, (2) these viruses have the largest RNA virus genome and, in principle, have room for the insertion of large foreign genes, (3) a pleiotropic secretory immune response is best induced by the stimulation of gut-associated lymphoid tissues, (4) the tropism of coronaviruses may be modified by manipulation of the spike (S) protein allowing engineering of the tropism of the vector, (5) non-pathogenic coronavirus strains infecting most species of interest (human, porcine, bovine, canine, feline, and avian) are available to develop expression systems, and (6) infectious coronavirus cDNA clones are available to design expression systems. Within the coronavirus two types of expression vectors have been developed: one requires two components (helper–dependent expression system) and the other a single genome that is modified either by targeted recombination or by engineering a cDNA encoding an infectious RNA. This chapter focuses on the advantages and limitations of these coronavirus expression systems, the attempts to increase their expression levels by studying the transcription-regulating sequences (TRSs), and the proven possibility of modifying their tissue and species-specificity.


id: cord-328935-mn8r972x
title: Mucosal Veterinary Vaccines: Comparative Vaccinology
author: Hodgins, Douglas C.
date: 2015-03-13
txt: ./txt/cord-328935-mn8r972x.txt
cache: ./cache/cord-328935-mn8r972x.txt
extension: .txt
mime: text/plain
url: https://api.elsevier.com/content/article/pii/B9780124158474000689
doi: 10.1016/b978-0-12-415847-4.00068-9
summary:
  Studies of the potential of novel adjuvants to improve vaccine efficacy against genetically unstable, immune-subverting RNA viruses, such as porcine reproductive and respiratory syndrome virus in pigs, should assist in the control of pathogens with similar characteristics in other species. However, a recent study showed that an inactivated reassortant RV strain (CDC-9 strain) formulated with aluminum phosphate and administered systemically in gnotobiotic pigs resulted in induction of serum IgG antibody titers, coinciding with partial protection against shedding and diarrhea, suggesting that adjuvant may have stimulated local specific (gut IgA antibodies) or nonspecific immune responses, which were not assessed in this study (Wang et al., 2010) . Intranasal delivery of whole cell lysate of Mycobacterium tuberculosis induces protective immune responses to a modified live porcine reproductive and respiratory syndrome virus vaccine in pigs

abstract:
  Infections of mucosal surfaces are major causes of morbidity, mortality, and economic loss in species of veterinary interest, and a concern for animal welfare. Vaccines are used extensively in veterinary medicine, and innovative vaccine technologies such as recombinant DNA-vectored and distinguishing infected from vaccinated animals (DIVA) vaccines and automated in ovo vaccination (of embryonated chicken eggs) have been rapidly adopted commercially. Immunological research using outbred, nonrodent animal models has contributed to a broader understanding of mucosal defenses, and has provided the initial impetus for investigation of the common mucosal immune system. Studies of the potential of novel adjuvants to improve vaccine efficacy against genetically unstable, immune-subverting RNA viruses, such as porcine reproductive and respiratory syndrome virus in pigs, should assist in the control of pathogens with similar characteristics in other species. Successful development of vaccines to prevent and treat ascending infections of the reproductive tract of cattle set a precedent for applications in other species including humans. Studies of mucosal adjuvants and delivery systems continue at the interface between passive and active immunity, with the goal of inducing the earliest possible protection against enteric and respiratory pathogens of neonates.


id: cord-329819-dpgexphf
title: Epidermal growth factor receptor is a co-factor for transmissible gastroenteritis virus entry
author: Hu, Weiwei
date: 2018-06-04
txt: ./txt/cord-329819-dpgexphf.txt
cache: ./cache/cord-329819-dpgexphf.txt
extension: .txt
mime: text/plain
url: https://api.elsevier.com/content/article/pii/S0042682218301508
doi: 10.1016/j.virol.2018.05.009
summary:
  IPEC-J2 cells were infected with TGEV (MOI = 2) and cultured for 30 min, then stained for fluorescence microscopy using mouse anti-APN pAb, followed by DyLight 488-conjugated goat anti-mouse IgG and rabbit anti-p-EGFR mAb, followed by DyLight 594-conjugated goat anti-rabbit IgG. Plaque formation in ST cells by the intracellular of infected IPEC-J2 cells showed that APN + EGFR-targeting shRNAs inhibited TGEV entry more significantly (Fig. 3G) . To explore the role of caveolin and clathrin in EGFR internalization early in TGEV infection, we reduced clathrin or caveolin down in normal IPEC-J2 cells through targeting shRNAs, and investigated cell membrane EGFR expression levels during TGEV invasion. We can get to the conclusion that in the early infection stage of TGEV, TGEV particles bound with APN and EGFR, the virus-receptors complex are subsequently internalized by clathrin.

abstract:
  Transmissible gastroenteritis virus (TGEV) causes severe diarrhea and high mortality in newborn piglets. It is well established that porcine intestinal epithelium is the target of the TGEV infection, however the mechanism that TGEV invades the host epithelium remains largely unknown. Aminopeptidase N (APN) is a known receptor of TGEV. This study discovered that the extracellular receptor binding domain 1 pertaining to epidermal growth receptor (EGFR) interact with TGEV spike protein. APN and EGFR synergistically promote TGEV invasion. TGEV promotes APN and EGFR clustering early in infection. Furthermore APN and EGFR synergistically stimulate PI3K/AKT as well as MEK/ERK1/2 endocytosis signaling pathways. TGEV entry is via clathrin and caveolin mediated endocytosis in IPEC-J2 cells. TGEV binds with EGFR, and subsequently promotes EGFR internalization by a clathrin-mediated endocytosis pathway. These results show that EGFR is a co-factor of TGEV, and that it plays a synergistic role with APN early in TGEV infection.


id: cord-332317-wrztpeb8
author: Zhang, Xin
date: 2015-03-16
url: https://www.ncbi.nlm.nih.gov/pubmed/25533531/
doi: 10.1016/j.virusres.2014.12.013
title:
  Identification of the interaction between vimentin and nucleocapsid protein of transmissible gastroenteritis virus

abstract:
  Nucleocapsid (N) protein of transmissible gastroenteritis virus (TGEV) packages viral RNA genome to form a ribonucleoprotein complex. In addition to its function as a structural protein, N protein is involved in cell apoptosis or cell-cycle regulation. N protein possibly interacts with host factors to modulate cellular functions. To identify cellular proteins that interacted with N protein of TGEV, methods of GST pull-down and Co-IP were utilized to precipitate cellular proteins of swine testicular (ST). Bound cellular proteins were resolved by SDS-PAGE. Analysis of interacting proteins by mass spectrometry allowed identification of 15 cellular protein bands representative of 12 cellular proteins including vimentin that bound to N protein. Furthermore, the function of vimentin cytoskeleton in ST cells during TGEV infection was examined. Vimentin cytoskeleton was required for virus replication. The present study thus provides protein-related information about interaction of TGEV N protein with host cell that should be useful for understanding host cell response to coronavirus pathogenesis infection and the underlying mechanism of coronavirus replication.


id: cord-332358-0t4uxmj2
author: Lamphear, Barry J.
date: 2004-06-23
url: https://www.ncbi.nlm.nih.gov/pubmed/15193404/
doi: 10.1016/j.vaccine.2003.11.066
title:
  A corn-based delivery system for animal vaccines: an oral transmissible gastroenteritis virus vaccine boosts lactogenic immunity in swine

abstract:
  Recombinant plant expression systems offer a means to produce large quantities of selected antigens for subunit vaccines. Cereals are particularly well-suited expression vehicles since the expressed proteins can be stored at relatively high concentrations for extended periods of time without degradation and dry seed can be formulated into oral vaccines suitable for commercial applications. A subunit vaccine candidate directed against porcine transmissible gastroenteritis virus and expressed in corn seed has been developed for oral delivery to swine. Here, we show that this vaccine, when administered to previously sensitized gilts, can boost neutralizing antibody levels in the animals’ serum, colostrum and milk. Thus, this vaccine candidate is effective at boosting lactogenic immunity and is appropriate to pursue through large-scale field trials preceding commercialization.


id: cord-337498-zp697h4k
author: Zhao, Xiaomin
date: 2017-12-07
url: https://www.ncbi.nlm.nih.gov/pubmed/29217619/
doi: 10.1074/mcp.ra117.000432
title:
  microRNA-4331 Promotes Transmissible Gastroenteritis Virus (TGEV)-induced Mitochondrial Damage Via Targeting RB1, Upregulating Interleukin-1 Receptor Accessory Protein (IL1RAP), and Activating p38 MAPK Pathway In Vitro

abstract:
  Transmissible gastroenteritis virus (TGEV), a member of the coronaviridae family, could cause fatal diarrhea of piglets and result in numerous economic losses. Previous studies demonstrated that TGEV infection could lead to mitochondrial damage and upregulate miR-4331 level. So miR-4331 may play an important regulatory role in the control of mitochondrial function. To explore the potential role of miR-4331 in mitochondrial damage, we adopted a strategy consisting of quantitative proteomic analysis of porcine kidney (PK-15) cells in response to miR-4331 and TGEV infection. Eventually, 69 differentially expressed proteins were gained. The target of miR-4331 was identified. The effects of miR-4331 and its target RB1 on mitochondrial Ca(2+) level, mitochondrial membrane potential (MMP), interleukin-1 receptor accessory protein (IL1RAP), p38 MAPK signaling pathway were investigated. The results showed that miR-4331 elevated mitochondrial Ca(2+) level, reduced MMP, targets Retinoblastoma 1 (RB1), upregulated IL1RAP, and induced activation of p38 MAPK pathway during TGEV infection. RB1 was identified as the direct targets of miR-4331 and downregulated IL1RAP, suppressed the activation of p38 MPAK, and attenuated TGEV-induced mitochondrial damage. In addition, IL1RAP played a positive role in activating p38 MAPK signaling and negative role in TGEV-induced mitochondrial damage. The data indicate that miR-4331 aggravates TGEV-induced mitochondrial damage by repressing expression of RB1, promoting IL1RAP, and activating p38 MAPK pathway.


id: cord-337645-t6py0oyw
author: Yin, Jiechao
date: 2010-10-14
url: https://api.elsevier.com/content/article/pii/S0166354210007448
doi: 10.1016/j.antiviral.2010.10.002
title:
  Cholesterol is important for a post-adsorption step in the entry process of transmissible gastroenteritis virus

abstract:
  Cholesterol is a major constituent of detergent-resistant membrane microdomains (DRMs). We localized transmissible gastroenteritis virus (TGEV) spike (S) protein in DRMs in the viral envelope. Though S protein was not solubilized by cold non-ionic detergents, this behavior was unchanged when cholesterol was depleted from viral membrane by methyl-β-cyclodextrin (MβCD) and the protein did not comigrate with cellular DRM marker proteins in flotation analyses. Therefore, the S protein is not anchored in the viral membrane DRMs as they are known to occur in the plasma membrane. Cholesterol depletion from viral membrane may not affect the adsorption process as neither the sialic acid binding activity nor the binding to aminopeptidase N was reduced post-MβCD treatment. Reduced infectivity of cholesterol-depleted TGEV was observed only when the adsorption process occurred at 37 °C but not when the virus was applied at 4 °C. Cholesterol is important for a post-adsorption step, allowing membrane rearrangements that facilitate virus entry.


id: cord-339178-d6f6a5ds
title: A new coronavirus-like particle associated with diarrhea in swine
author: Pensaert, M. B.
date: 1978
url: https://www.ncbi.nlm.nih.gov/pubmed/83132/
doi: 10.1007/bf01317606
abstract:
  Coronavirus-like particles were detected by electron microscopy in the intestinal contents of pigs during a diarrheal outbreak on 4 swine breeding farms. Diarrhea was reproduced in experimental pigs with one of the isolates, designated CV777, which was found to be distinct from the 2 known porcine coronaviruses, transmissible gastroenteritis virus and hemagglutinating encephalomyelitis virus.


id: cord-339694-sp212tai
author: Jiang, Xinpeng
date: 2016-03-28
url: https://www.ncbi.nlm.nih.gov/pubmed/27020282/
doi: 10.1007/s00253-016-7424-9
title:
  A phase trial of the oral Lactobacillus casei vaccine polarizes Th2 cell immunity against transmissible gastroenteritis coronavirus infection

abstract:
  Transmissible gastroenteritis coronavirus (TGEV) is a member of the genus Coronavirus, family Coronaviridae, order Nidovirales. TGEV is an enteropathogenic coronavirus that causes highly fatal acute diarrhoea in newborn pigs. An oral Lactobacillus casei (L. casei) vaccine against anti-transmissible gastroenteritis virus developed in our laboratory was used to study mucosal immune responses. In this L. casei vaccine, repetitive peptides expressed by L. casei (specifically the MDP and tuftsin fusion protein (MT)) were repeated 20 times and the D antigenic site of the TGEV spike (S) protein was repeated 6 times. Immunization with recombinant Lactobacillus is crucial for investigations of the effect of immunization, such as the first immunization time and dose. The first immunization is more important than the last immunization in the series. The recombinant Lactobacillus elicited specific systemic and mucosal immune responses. Recombinant L. casei had a strong potentiating effect on the cellular immunity induced by the oral L. casei vaccine. However, during TGEV infection, the systemic and local immune responses switched from Th1 to Th2-based immune responses. The systemic humoral immune response was stronger than the cellular immune response after TGEV infection. We found that the recombinant Lactobacillus stimulated IL-17 expression in both the systemic and mucosal immune responses against TGEV infection. Furthermore, the Lactobacillus vaccine stimulated an anti-TGEV infection Th17 pathway. The histopathological examination showed tremendous potential for recombinant Lactobacillus to enable rapid and effective treatment for TGEV with an intestinal tropism in piglets. The TGEV immune protection was primarily dependent on mucosal immunity.


id: cord-341015-45kbggzk
author: Galán, Carmen
date: 2006
url: https://www.ncbi.nlm.nih.gov/pubmed/17037508/
doi: 10.1007/978-0-387-33012-9_12
abstract: nan
title:
  Differential role of N-Terminal Polyprotein Processing in Coronavirus Genome Replication and Minigenome Amplification


id: cord-341690-h8fqijk5
author: Hu, Weiwei
date: 2016-02-25
txt: ./txt/cord-341690-h8fqijk5.txt
cache: ./cache/cord-341690-h8fqijk5.txt
extension: .txt
mime: text/plain
url: https://doi.org/10.18632/oncotarget.7723
doi: 10.18632/oncotarget.7723
summary:
  title: The epidermal growth factor receptor regulates cofilin activity and promotes transmissible gastroenteritis virus entry into intestinal epithelial cells The TGEV spike protein is capable of binding with EGFR, activating the downstream phosphoinositide-3 kinase (PI3K), then causing the phosphorylation of cofilin and F-actin polymerization via Rac1/Cdc42 GTPases. We found that TGEV acted via the EGFR-PI3K-Rac1/Cdc42-PAK-LIMK signaling pathway to regulate the activity of cofilin and F-actin arrangement early in infection, and also demonstrated that EGFR was a promoter for TGEV entry. During the early phase of TGEV infection, the destruction of lipid rafts inhibited the activation of EGFR, Akt, and LIMK, and also inhibited the phosphorylation of cofilin ( Figure 7E ). Our results also indicate that TGEV binding induces the phosphorylation of cofilin through the EGFR-PI3K-Rac1/ Cdc42-PAK-LIMK signaling pathways, resulting in actin polymerization around the cell membrane and foming multiple poutrusions.

title:
  The epidermal growth factor receptor regulates cofilin activity and promotes transmissible gastroenteritis virus entry into intestinal epithelial cells

abstract:
  Transmissible gastroenteritis virus (TGEV), a coronavirus, causes severe diarrhea and high mortality in newborn piglets. The porcine intestinal epithelium is the target of TGEV infection, but the mechanisms that TGEV disrupts the actin cytoskeleton and invades the host epithelium remain largely unknown. We not only found that TGEV infection stimulates F-actin to gather at the cell membrane but the disruption of F-actin inhibits TGEV entry as well. Cofilin is involved in F-actin reorganization and TGEV entry. The TGEV spike protein is capable of binding with EGFR, activating the downstream phosphoinositide-3 kinase (PI3K), then causing the phosphorylation of cofilin and F-actin polymerization via Rac1/Cdc42 GTPases. Inhibition of EGFR and PI3K decreases the entry of TGEV. EGFR is also the upstream activator of mitogen-activated protein kinase (MAPK) signaling pathways that is involved in F-actin reorganization. Additionally, lipid rafts act as signal platforms for the EGFR-associated signaling cascade and correlate with the adhesion of TGEV. In conlusion, these results provide valuable data of the mechanisms which are responsible for the TGEV pathogenesis and may lead to the development of new methods about controlling TGEV.


id: cord-341860-a6yoz3w1
author: Zhao, Xiaomin
date: 2016-02-04
url: https://www.ncbi.nlm.nih.gov/pubmed/26870610/
doi: 10.7717/peerj.1635
title:
  miR-27b attenuates apoptosis induced by transmissible gastroenteritis virus (TGEV) infection via targeting runt-related transcription factor 1 (RUNX1)

abstract:
  Transmissible gastroenteritis virus (TGEV), belonging to the coronaviridae family, is the key cause of the fatal diarrhea of piglets and results in many pathological processes. microRNAs (miRNAs) play a key role in the regulation of virus-induced apoptosis. During the process of apoptosis induced by TGEV infection in PK-15 cells, the miR-27b is notably down-regulated. Thus, we speculate that miR-27b is involved in regulating the process of apoptosis in PK-15 cells. In this study we demonstrated that the over-expression of miR-27b led to the inhibition of TGEV-induced apoptosis, reduction of Bax protein level, and decrease of caspase-3 and −9 activities. Conversely, silencing of miR-27b by miR-27b inhibitors enhanced apoptosis via up-regulating Bax expression and promoting the activities of caspase-3 and −9 in TGEV-infected cells. Subsequently, the runt-related transcription factor 1 (RUNX1) is a candidate target of miR-27b predicted by bioinformatics search. We further identified that the miR-27b directly bound to the 3′ UTR of RUNX1 mRNA and suppressed RUNX1 expression, which indicates RUNX1 is the direct target gene of miR-27b. The over-expression of RUNX1 increased apoptosis and knockdown RUNX1blocked apoptosis of viral-infected cells via regulating Bax expression and the activities of caspase-3 and −9. Our data reveal that miR-27b may repress the mitochondrial pathway of apoptosis by targeting RUNX1, indicating that TGEV may induce apoptosis via down-regulating miR-27b and that miR-27b may act as a target for therapeutic intervention.


id: cord-342289-zpstb7h9
author: Cui, Tingting
date: 2018-10-12
url: https://www.ncbi.nlm.nih.gov/pubmed/30315177/
doi: 10.1038/s41598-018-33305-1
title:
  Establishment of porcine enterocyte/myofibroblast co-cultures for the growth of porcine rota- and coronaviruses

abstract:
  A stable culture of primary porcine enterocytes is necessary to study porcine enteric virus replication characteristics. Because the direct cultivation of primary porcine enterocytes is difficult, alternatives have to be considered. As subepithelial myofibroblasts secrete extracellular matrix and growth factors contributing to the attachment, proliferation and differentiation of epithelial cells, co-cultures of primary porcine enterocytes (ileocytes and colonocytes) with myofibroblasts were developed and evaluated for their susceptibility to enteric viruses. First, it was demonstrated that the co-cultured ileocytes and colonocytes were susceptible to an archival rotavirus strain RVA/pig-tc/BEL/RV277/1977/G1P[7] and different other rotavirus genotypes (fecal samples containing G5P[7], G5P[13], G9P[23], G4P[6]). Next, the TGEV Purdue strain infected both ileocytes and colonocytes whereas the Miller strain only infected ileocytes. Last, the PEDV CV777 Vero adapted and non-adapted (fecal suspension) strains could infect co-cultured ileocytes but not colonocytes. The infectivity of the CV777 Vero adapted strain was higher when the cells were cultured without fetal bovine serum and the CV777 fecal suspension only infected the ileocytes cultured without fetal bovine serum. In conclusion, a novel co-culture of porcine enterocytes with myofibroblasts was established, which can be used for the investigation of the replication of enteric viruses.


id: cord-344558-1jgqofbr
title: Completion of the Porcine Epidemic Diarrhoea Coronavirus (PEDV) Genome Sequence
author: Kocherhans, Rolf
date: 2001
url: https://www.ncbi.nlm.nih.gov/pubmed/11724265/
doi: 10.1023/a:1011831902219
abstract:
  The sequence of the replicase gene of porcine epidemic diarrhoea virus (PEDV) has been determined. This completes the sequence of the entire genome of strain CV777, which was found to be 28,033 nucleotides (nt) in length (excluding the poly A-tail). A cloning strategy, which involves primers based on conserved regions in the predicted ORF1 products from other coronaviruses whose genome sequence has been determined, was used to amplify the equivalent, but as yet unknown, sequence of PEDV. Primary sequences derived from these products were used to design additional primers resulting in the amplification and sequencing of the entire ORF1 of PEDV. Analysis of the nucleotide sequences revealed a small open reading frame (ORF) located near the 5′ end (no 99–137), and two large, slightly overlapping ORFs, ORF1a (nt 297–12650) and ORF1b (nt 12605–20641). The ORF1a and ORF1b sequences overlapped at a potential ribosomal frame shift site. The amino acid sequence analysis suggested the presence of several functional motifs within the putative ORF1 protein. By analogy to other coronavirus replicase gene products, three protease and one growth factor-like motif were seen in ORF1a, and one polymerase domain, one metal ion-binding domain, and one helicase motif could be assigned within ORF1b. Comparative amino acid sequence alignments revealed that PEDV is most closely related to human coronavirus (HCoV)-229E and transmissible gastroenteritis virus (TGEV) and less related to murine hepatitis virus (MHV) and infectious bronchitis virus (IBV). These results thus confirm and extend the findings from sequence analysis of the structural genes of PEDV.


id: cord-345651-admlzeu4
author: Wang, Gang
date: 2019-03-30
url: https://www.ncbi.nlm.nih.gov/pubmed/30935078/
doi: 10.3390/v11040313
title:
  The N-Terminal Domain of Spike Protein Is Not the Enteric Tropism Determinant for Transmissible Gastroenteritis Virus in Piglets

abstract:
  Transmissible gastroenteritis virus (TGEV) is the etiologic agent of transmissible gastroenteritis in pigs, and the N-terminal domain of TGEV spike protein is generally recognized as both the virulence determinant and enteric tropism determinant. Here, we assembled a full-length infectious cDNA clone of TGEV in a bacterial artificial chromosome. Using a novel approach, the clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) systems efficiently and rapidly rescued another recombinant virus with a 224-amino-acid deletion in the N-terminal domain of the TGEV Spike gene (S_NTD224), which is analogous to the N-terminal domain of porcine respiratory coronavirus. S_NTD224 notably affected the TGEV growth kinetics in PK-15 cells but was not essential for recombinant virus survival. In animal experiments with 13 two-day-old piglets, the TGEV recombinant viruses with/without S_NTD224 deletion induced obvious clinical signs and mortality. Together, our results directly demonstrated that S_NTD224 of TGEV mildly influenced TGEV virulence but was not the enteric tropism determinant and provide new insights for the development of a new attenuated vaccine against TGEV. Importantly, the optimized reverse genetics platform used in this study will simplify the construction of mutant infectious clones and help accelerate progress in coronavirus research.


id: cord-346643-os2kyvvf
author: Wang, Li
date: 2016-11-15
url: https://doi.org/10.1007/s11262-016-1409-8
doi: 10.1007/s11262-016-1409-8
title:
  Inhibition of porcine transmissible gastroenteritis virus infection in porcine kidney cells using short hairpin RNAs targeting the membrane gene

abstract:
  The membrane (M) protein is the most abundant component of the porcine transmissible gastroenteritis virus (TGEV) particle. To exploit the possibility of using RNA interference (RNAi) as a strategy against TGEV infection, three plasmids (pRNAT-1, pRNAT-2, and pRNAT-3) expressing short hairpin RNAs were designed to target three different coding regions of the M gene of TGEV. The plasmids were constructed and transiently transfected into a porcine kidney cells, PK-15, to determine whether these constructs inhibited TGEV production. The analysis of cytopathic effects demonstrated that pRNAT-2 and pRNAT-3 could protect PK-15 cells against pathological changes specifically and efficiently. Additionally, indirect immunofluorescence and 50% tissue culture infectious dose (TCID(50)) assays showed that pRNAT-2 and pRNAT-3 inhibited the multiplication of the virus at the protein level effectively. Quantitative real-time PCR further confirmed that the amounts of viral RNAs in cell cultures pre-transfected with the three plasmids were reduced by 13, 68, and 70%, respectively. This is the first report showing that RNAi targeting of the M gene. Our results could promote studies of the specific function of viral genes associated with TGEV infection and might provide a theoretical basis for potential therapeutic applications.


id: cord-346872-k5d5793a
author: Yuan, Peng
date: 2018-09-03
txt: ./txt/cord-346872-k5d5793a.txt
cache: ./cache/cord-346872-k5d5793a.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/30176660/
doi: 10.1159/000492424
summary:
  Both viruses establish an infection in porcine enterocytes in the small intestine, and their spike (S) proteins play a key role in the virus-cell binding process under unfavorable conditions when the intestine with a low pH is filled with a thick layer of mucus and proteases. This review emphasizes the role of three factors (sialic acid, proteases, and low pH) in the invasion of TGEV and PEDV into porcine small intestine epithelial cells and provides information with respect to α-CoV infection that brings new insights into virus research. Like TGEV, the crystal structure of a single domain unit in the PRCoV RBD adopts a β-barrel fold with 2 highly twisted β-sheets located in the CTD of the S1 domain and engages in binding to the host cell surface receptor. Low pH in the initial stage of PEDV entry into intestinal epithelial cells allows structural changes and protease activation during binding to surface receptors.

title:
  Three Main Inducers of Alphacoronavirus Infection of Enterocytes: Sialic Acid, Proteases, and Low pH

abstract:
  Transmissible gastroenteritis virus (TGEV) and porcine epidemic diarrhea virus (PEDV) are similar coronaviruses, causing diseases characterized by vomiting, diarrhea, and death from severe dehydration in piglets. Thus, they have caused huge losses to the swine-breeding industry worldwide. Nowadays, they are easily transmitted among the continents via vehicles, equipment, and cargo. Both viruses establish an infection in porcine enterocytes in the small intestine, and their spike (S) proteins play a key role in the virus-cell binding process under unfavorable conditions when the intestine with a low pH is filled with a thick layer of mucus and proteases. Sialic acid, proteases, and low pH are three main inducers of coronavirus infection. However, the details of how sialic acid and low pH affect virus binding to the host cell are not determined, and the functions of the proteases are unknown. This review emphasizes the role of three factors in the invasion of TGEV and PEDV into porcine enterocytes and offers more insights into Alphacoronavirus infection in the intestinal environment.


id: cord-346928-g1dqiki6
author: Costantini, V.
date: 2003-11-26
txt: ./txt/cord-346928-g1dqiki6.txt
cache: ./cache/cord-346928-g1dqiki6.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/15098110/
doi: 10.1007/s00705-003-0245-z
summary:
  Porcine respiratory coronavirus (PRCV), a spike (S) gene deletion mutant of Transmissible gastroenteritis virus (TGEV), causes mild or subclinical respiratory infections in pigs. In preliminary studies, inoculation of gnotobiotic pigs with each plaque-purified pair of the nasal and fecal PRCV isolates, revealed no clinical disease but different tropisms. Fecal and nasal swabs from the field cases (sentinel pigs), cell culture isolates and fecal and nasal swabs from gnotobiotic pigs were tested by nested-RT-PCR to detect and to differentiate TGEV and PRCV viral RNA as previously described by Kim et al. Fecal and nasal swab supernatant fluids from the sentinel field cases or the cell culture passaged PRCV isolates and nasal and fecal swabs from gnotobiotic pigs were diluted in minimum essential medium (MEM-E) and tested by CCIF to detect infectious virus using previously described procedures [23] .

title:
  Respiratory and fecal shedding of Porcine respiratory coronavirus (PRCV) in sentinel weaned pigs and sequence of the partial S-gene of the PRCV isolates

abstract:
  Porcine respiratory coronavirus (PRCV), a spike (S) gene deletion mutant of Transmissible gastroenteritis virus (TGEV), causes mild or subclinical respiratory infections in pigs. The shedding of PRCV/TGEV was studied at different days post-arrival in fecal and nasal swabs from PRCV/TGEV seronegative sentinel pigs introduced into a PRCV seropositive herd with questionable TGEV serology and diarrhea. Nasal shedding of PRCV was detected in 57% and 63% of samples by nested-RT-PCR and cell culture immunofluorescence (CCIF), respectively. However fecal shedding of PRCV was detected in 37% of the samples by nested-RT-PCR and 19% by CCIF. Four respiratory and 5 fecal PRCV strains were isolated in swine testicle cells including nasal/fecal PRCV pairs (isolated at the same time) from 3 pigs. Comparison of nasal/fecal PRCV pairs from individual pigs revealed different deletions in the spike (S) gene (648 or 681 nt) in 2 pairs and a consistent change in nt 790/791 (aa T to V) for all pairs. In preliminary studies, inoculation of gnotobiotic pigs with each plaque-purified pair of the nasal and fecal PRCV isolates, revealed no clinical disease but different tropisms. The nasal isolate was shed both nasally and in feces, but the fecal isolate was shed only marginally in feces, and not nasally. Our results show that nested-RT-PCR was as sensitive as CCIF for PRCV detection in nasal swabs, but was more sensitive than CCIF for PRCV detection in fecal samples; alternatively PRCV shed in feces was more labile with loss of infectivity. The S-gene sequence differences found between the fecal and respiratory PRCV isolates may influence their tissue tropism. These new PRCV isolates should be useful to understand the molecular basis of coronavirus tropism and evolution in infected swine.


id: cord-348896-a2mjj5dt
author: Abid, Nabil Ben Salem
date: 2010-12-28
txt: ./txt/cord-348896-a2mjj5dt.txt
cache: ./cache/cord-348896-a2mjj5dt.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/21188626/
doi: 10.1007/s11262-010-0562-8
summary:
  Although these deletions were positioned at the beginning of the antigenic site B of S protein, no clinical differences were observed in piglets infected experimentally either with the native virus or the mutated one. The objective of this study was to carry out a typical experiment to compare two TGEV TMK22 strains, one of which was cell culture, adapted and maintained in the laboratory for about 15 years, and the other virus was passed in animals during the same period of time. Overall, the clinical signs observed in piglets, infected with the cell culture adapted TMK22 and pTMK22 strains, were consistent with a typical TGEV infection and did not show any clinical difference in these typical experiments. As shown in Table 2 , the genome of TGEV was detected by RT-PCR in stool samples of the all 1-week-old infected piglets either by TMK22 or pTMK22 strains 24 hpi.

title:
  Molecular study of porcine transmissible gastroenteritis virus after serial animal passages revealed point mutations in S protein

abstract:
  Porcine respiratory coronavirus is related genetically to porcine transmissible gastroenteritis virus with a large deletion in S protein. The respiratory virus is a mutated form that may be a consequence of the gastroenteritis virus’s evolution. Intensive passages of the virus in its natural host may enhance the appearance of mutations and therefore may contribute to any attenuated form of the virus. The objective of this study was to characterize the porcine transmissible gastroenteritis virus TMK22 strain after passages in piglets from 1992 until 2007. A typical experimental infection, molecular characterization, and serological analysis were also carried out to further characterize and to evaluate any significant difference between strains. The sequence analysis showed two amino acid deletions and loss of an N-glycosylation site in transmissible gastroenteritis virus S protein after passages in piglets. Although these deletions were positioned at the beginning of the antigenic site B of S protein, no clinical differences were observed in piglets infected experimentally either with the native virus or the mutated one. Serological tests did not show any antibody reactivity difference between the two strains. In this article, we report that the S protein deletion did not affect the virus’s pathogenicity. The variety of the virus’s evolutionary forms may be a result, not only of the multiple passages in natural hosts, but also of other factors, such as different pathogens co-infection, nutrition, immunity, and others. Further studies need to be carried out to characterize the mutated strain.


id: cord-349800-s9w2yr08
author: Hohdatsu, T.
date: 1991
txt: ./txt/cord-349800-s9w2yr08.txt
cache: ./cache/cord-349800-s9w2yr08.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/1706593/
doi: 10.1007/bf01310494
summary:
  Seven monoclonal antibodies (MAbs) with neutralizing activity against feline infectious peritonitis virus (FIPV) strain 79-1149 (type II) were prepared. The reactivity of these MAbs with 6 viruses classified as FIPV type I (UCD-1, UCD-2, UCD-3, UCD-4, NW-1, and Black), feline enteric coronavirus (FECV) type II strain 79-1683, canine coronavirus (CCV) strain 1-71, and transmissible gastroenteritis virus (TGEV) strains TO-163 and SH was examined by neutralization tests. Feline coronaviruses are divided into FIPV types I and II, and FECV types I and II, on the basis of the disease types, that is, whether it causes feline infectious peritonitis (FIP) or not, the ability of the viruses to proliferate in cell cultures, and the antigenic relationship to TGEV and CCV [17] . These MAbs did not neutralize the 6 FIPV type I viruses, but neutralized FECV strain 79-1683, TGEV strains TO-163 and SH, and CCV strain 1-71, which do not cause feline infectious peritonitis (Table 4) .

title:
  Characterization of monoclonal antibodies against feline infectious peritonitis virus type II and antigenic relationship between feline, porcine, and canine coronaviruses

abstract:
  Seven monoclonal antibodies (MAbs) with neutralizing activity against feline infectious peritonitis virus (FIPV) strain 79-1149 (type II) were prepared. When the polypeptide specificity recognized by these monoclonal antibodies (MAbs) was investigated by Western immunoblotting, all of the MAbs reacted with peplomer glycoprotein (S) of the virus. By competitive binding assay these MAbs were found to recognize at least 3 different epitopes. The reactivity of these MAbs with 6 viruses classified as FIPV type I (UCD-1, UCD-2, UCD-3, UCD-4, NW-1, and Black), feline enteric coronavirus (FECV) type II strain 79-1683, canine coronavirus (CCV) strain 1-71, and transmissible gastroenteritis virus (TGEV) strains TO-163 and SH was examined by neutralization tests. All MAbs neutralized FECV strain 79-1683, CCV strain 1-71, and TGEV strains TO-163 and SH, while they did not neutralize the 6 FIPV type I viruses. Moreover, the MAb against TGEV strain TO-163, which has strong neutralizing activity against 7 TGEV viruses, neutralized CCV strain 1-71, FECV strain 79-1683, and FIPV strain 79-1146, but did not neutralize the 6 FIPV type I viruses. These results demonstrated that there are at least 3 epitopes involved in the neutralization of FIPV type II strain 79-1146, and that these epitopes are not present in FIPV type I viruses but are present in FECV strain 79-1683 which does not induce feline infectious peritonitis, TGEV strains TO-163 and SH, and CCV strain 1-71. These results suggest the presence of 2 serotypes of FIPV which can be clearly distinguished by the neutralization test using MAbs.


id: cord-349964-38rgcc5h
title: Antigenic relationship of the feline infectious peritonitis virus to coronaviruses of other species
author: Pedersen, N. C.
date: 1978
url: https://www.ncbi.nlm.nih.gov/pubmed/81044/
doi: 10.1007/bf01315534
abstract:
  Utilizing the direct and indirect fluorescent antibody procedure, the antigenic relationship of the feline infectious peritonitis virus (FIPV) to 7 other human and animal coronaviruses was studied. FIPV was found to be closely related to transmissible gastroenteritis virus (TGEV) of swine. Transmissible gastroenteritis virus and FIPV were in turn antigenically related to human coronavirus 229E (HCV-229E) and canine coronavirus (CCV). An interesting finding in the study was that the 8 coronaviruses selected for this study fell into one of two antigenically distinct groups. Viruses in each group were antigenically related to each other to varying degrees, but were antigenically unrelated to coronaviruses of the second group. The first antigenically related group was comprised of mouse hepatitis virus, type 3 (MHV-3), hemeagglutinating encephalomyelitis virus 67N (HEV-67N) of swine, calf diarrhea coronavirus (CDCV), and human coronavirus OC43 (HCV-OC43). The second antigenically related group was comprised of FIPV, TGEV, HCV-229E and CCV.


id: cord-354904-7gq2e6f0
title: Prospects for the use of spherical gold nanoparticles in immunization
author: Staroverov, Sergey A.
date: 2018-11-06
txt: ./txt/cord-354904-7gq2e6f0.txt
cache: ./cache/cord-354904-7gq2e6f0.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/30402771/
doi: 10.1007/s00253-018-9476-5
summary:
  We used spherical gold nanoparticles (average diameter, 15 nm) as a platform for the antigen for swine transmissible gastroenteritis virus (TGEV). The literature data demonstrate that immunization of animals with the TGEV antigen coupled to gold nanoparticles (GNPs) not only activates antigen-presenting cells but also increases the proliferative activity of splenic lymphoid (antibody-forming) cells. Immunization with the TGEV antigen conjugated to GNPs as a carrier activates the respiratory activity of lymphoid cells and peritoneal macrophages, which is directly related to their transforming activity and to the activation of antibody generation. After the virus''s nucleic acid was inactivated with ribonuclease, the resultant antigen (a mixture of viral capsid proteins) was used for conjugation with GNPs and for subsequent animal immunization. A study of the respiratory activity of splenic lymphoid cells (Fig. 5) showed that after immunization with the conjugate, the activity increased 2.2-fold, as compared to the control, whereas after immunization with TGEV antigen alone, it did not change much.

abstract:
  Recent years have seen extremely fast development of new viral nanovaccines and diagnostic agents using nanostructures prepared by biological and chemical synthesis. We used spherical gold nanoparticles (average diameter, 15 nm) as a platform for the antigen for swine transmissible gastroenteritis virus (TGEV). The literature data demonstrate that immunization of animals with the TGEV antigen coupled to gold nanoparticles (GNPs) not only activates antigen-presenting cells but also increases the proliferative activity of splenic lymphoid (antibody-forming) cells. The contents of γ-IFN, IL-1β, and IL-6 in animals immunized with GNP-antigen conjugates were found to be higher than those in intact animals or in animals given the antigen alone. The increased concentration of IL-1β in the immunized animals directly correlated with the activity of macrophages and stimulated B cells, which produce this cytokine when activated. The increased concentration of IL-6 indicates that the injected preparations are stimulatory to cellular immunity. Immunization with the TGEV antigen conjugated to GNPs as a carrier activates the respiratory activity of lymphoid cells and peritoneal macrophages, which is directly related to their transforming activity and to the activation of antibody generation. Furthermore, the use of this conjugate allows marked improvement of the structure of the animals’ immune organs and restores the morphological–functional state of these organs. The microanatomical changes (increased number of follicles) indicate the activation of the B-dependent zone of the spleen and, consequently, the development of a humoral-type immunological reaction. The degradative processes observed in the animals immunized with TGEV antigen alone are evidence of weak resistance to pathogen attack. These results can be used to develop vaccines against this infection by employing TGEV antigen coupled to gold nanoparticles as a carrier.


id: cord-355499-5vj3oasa
author: Song, Xiangjun
date: 2015-06-07
txt: ./txt/cord-355499-5vj3oasa.txt
cache: ./cache/cord-355499-5vj3oasa.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/26157346/
doi: 10.7150/ijbs.11585
summary:
  title: Transmissible Gastroenteritis Virus (TGEV) Infection Alters the Expression of Cellular MicroRNA Species That Affect Transcription of TGEV Gene 7 In this study, we performed microRNA microarray assay and predicted targets of altered miRNAs. The results showed TGEV infection caused the change of miRNAs profile. In conclusion, differentially expressed miR-4331 that is caused by TGEV infection can suppress transcription of TGEV gene 7 via targeting cellular CDCA7. Overall, we observed that TGEV infection caused the change of miRNA profile and miR-4331 suppressed transcription of TGEV gene 7 via directly targeting CDCA7. The major findings in this study are that TGEV infection leads to the change of cellular miRNAs expression profile, and altered miRNAs regulate transcription of TGEV gene 7 through targeting cellular CDCA7. In conclusion, the results of the present study provide evidence that TGEV infection resulted in altered profiles of miRNAs in PK-15 cells and the differentially expressed miR-4331 was involved in regulation of TGEV transcription by targeting cellular CDCA7.

title:
  Transmissible Gastroenteritis Virus (TGEV) Infection Alters the Expression of Cellular MicroRNA Species That Affect Transcription of TGEV Gene 7

abstract:
  Transmissible gastroenteritis virus (TGEV) is a member of Coronaviridae family. TGEV infection has emerged as a major cause of severe gastroenteritis and leads to alterations of many cellular processes. Meanwhile, the pathogenic mechanism of TGEV is still unclear. microRNAs (miRNAs) are a novel class of small non-coding RNAs which are involved in the regulation of numerous biological processes such as viral infection and cell apoptosis. Accumulating data show that miRNAs are involved in the process of coronavirus infection such as replication of severe acute respiratory syndrome coronavirus (SARS-CoV). However, the link between miRNAs and TGEV infection is unknown. In this study, we performed microRNA microarray assay and predicted targets of altered miRNAs. The results showed TGEV infection caused the change of miRNAs profile. Then we selected miR-4331 for further analysis and subsequently identified cell division cycle-associated protein 7 (CDCA7) as the target of miR-4331. Moreover, miR-4331 showed the ability to inhibit transcription of TGEV gene 7 (a non-structure gene) via directly targeting CDCA7. In conclusion, differentially expressed miR-4331 that is caused by TGEV infection can suppress transcription of TGEV gene 7 via targeting cellular CDCA7. Our key finding is that TGEV selectively manipulates the expression of some cellular miRNAs to regulate its subgenomic transcription.


id: cord-355991-4zu69e0y
author: Piñeyro, Pablo Enrique
date: 2018-09-24
txt: ./txt/cord-355991-4zu69e0y.txt
cache: ./cache/cord-355991-4zu69e0y.txt
extension: .txt
mime: text/plain
url: https://www.ncbi.nlm.nih.gov/pubmed/30249258/
doi: 10.1186/s12917-018-1615-9
summary:
  The epidemiological and clinical presentations of outbreaks of neonatal mortality associated with enteritis and the detection of TGEV started in the gestation units. When TGEV enters in a naïve herds, an epizootic form characterized by a 100% mortality of pre-weaning piglets due to diarrhea and dehydration is normally observed [1, 14] . In this study, although all cases were selected using clinical features and epidemiological information, the histological evaluation consistently showed lesions compatible with viral infection. The application of IHC and ISH-RNA on archived paraffin blocks from cases of neonatal diarrhea with high morbidity and mortality allowed retrospective identification of TGEV infection. During the period when the sows showed gastro-enteric clinical signs, 2-to 4-day-old piglets presented vomiting (75-80%) and diarrhea (90%), and the mortality rate of suckling pigs reached 90%. Emergence of porcine epidemic diarrhea virus in the United States: clinical signs, lesions, and viral genomic sequences

title:
  First retrospective studies with etiological confirmation of porcine transmissible gastroenteritis virus infection in Argentina

abstract:
  BACKGROUND: In 2014, a notification of porcine transmissible gastroenteritis virus (TGEV) was made by the National Services of Animal Health of Argentina (SENASA) to the World Organization of Animal Health (OIE). The notification was based on a serological diagnosis in a small farm with a morbidity rate of 2.3% without enteric clinical signs. In order to determine if TGEV was circulating before the official report, a retrospective study on cases of neonatal diarrhea was performed. The selection criteria was a sudden increase in mortality in 1- to 21-day-old piglets with watery diarrhea that did not respond to antibiotics. Based on these criteria, three clinical cases were identified during 2010–2015. RESULTS: All animals that were evaluated presented histological lesions consistent with enteric viral infection. The feces and ultrathin sections of intestine that were evaluated by electron microscopy confirmed the presence of round particles of approximately 80 nm in size and characterized by finely granular electrodense nucleoids consistent with complete particles of coronavirus. The presence of the TGEV antigen was confirmed by monoclonal specific immunohistochemistry, and final confirmation of a metabolically-active virus was performed by in situ hybridization to detect a TGE mRNA encoding spike protein. All sections evaluated in this case were negative for PEDV and rotavirus A. CONCLUSIONS: This is the first case series describing neonatal mortality with etiological confirmation of TGEV in Argentina. The clinical diagnosis of TGEV infections in endemic regions is challenging due to the epidemiological distribution and coinfection with other enteric pathogens that mask the clinical presentation. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12917-018-1615-9) contains supplementary material, which is available to authorized users.


