key: cord-0870415-wslsqytj authors: Edara, V. V.; Floyd, K.; Lai, L.; Gardner, M.; Hudson, W.; Piantadosi, A.; Waggoner, J.; Babiker, A.; Ahmed, R.; Xie, X.; Lokugamage, K.; Menachery, V.; Shi, P.-Y.; COVID-19 Neutralization Study Group,; Suthar, M. S. title: Infection and mRNA-1273 vaccine antibodies neutralize SARS-CoV-2 UK variant date: 2021-02-05 journal: medRxiv : the preprint server for health sciences DOI: 10.1101/2021.02.02.21250799 sha: 71acd6bcd0c964c2a0d8eeb78d63469c626c4dad doc_id: 870415 cord_uid: wslsqytj Antibody responses against the SARS-CoV-2 Spike protein correlate with protection against COVID-19. Serum neutralizing antibodies appear early after symptom onset following SARS-CoV-2 infection and can last for several months. Similarly, the messenger RNA vaccine, mRNA-1273, generates serum neutralizing antibodies that are detected through at least day 119. However, the recent emergence of the B.1.1.7 variant has raised significant concerns about the breadth of these neutralizing antibody responses. In this study, we used a live virus neutralization assay to compare the neutralization potency of sera from infected and vaccinated individuals against a panel of SARS-CoV-2 variants, including SARS-CoV-2 B.1.1.7. We found that both infection- and vaccine-induced antibodies were effective at neutralizing the SARS-CoV-2 B.1.1.7 variant. These findings support the notion that in the context of the UK variant, vaccine-induced immunity can provide protection against COVID-19. As additional SARS-CoV-2 viral variants continue to emerge, it is crucial to monitor their impact on neutralizing antibody responses following infection and vaccination. COVID-19. Serum neutralizing antibodies appear within 10 days post-symptom onset (PSO) following SARS-CoV-2 infection 1 and are maintained for at least eight months 2 . Similarly, the messenger RNA vaccine, mRNA-1273, generates serum neutralizing antibodies that are detected through at least day 119 3 . The recent emergence of the SARS-CoV-2 B.1.1.7 variant raises concerns about the breadth of these neutralizing antibody responses. We describe the neutralizing antibody response in 20 acutely infected COVID-19 patients (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22) (23) (24) days PSO), 20 convalescent COVID-19 individuals (30-90 days PSO), and 14 healthy adult participants that received two injections of the mRNA-1273 vaccine at a dose of 100 µg (18-55 years; day 1 and day 14 post-2nd dose) 4 against a panel of SARS-CoV-2 variants. This includes an early from Seattle, WA 5 isolate (USA-WA1/2020), a later D614G variant isolated from a residual nasopharyngeal swab collected from a patient in Atlanta, GA in March 2020 (SARS-CoV-2/human/USA/GA-EHC-083E/2020), and a B.1.1.7 variant isolated from a residual nasopharyngeal swab collected from a patient in San Diego, CA (SARS-CoV-2/human/USA/CA_CDC_5574/2020). A recombinant SARS-CoV-2 containing a single point mutation within the spike at position 501 (Asn to Tyr) was also included 6 . The amino acid differences within the spike protein are described in Figure 1A . Serum neutralization titers were measured using a live-virus Focus Reduction Neutralization Test (FRNT) assay 7 and no reduction in the neutralization titers were observed in the variants compared to SARS-CoV-2 EHC-83E (Figure 1) (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted February 5, 2021. As additional SARS-CoV-2 viral variants continue to emerge, it is crucial to monitor their impact on neutralizing antibody responses following infection and vaccination. All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted February 5, 2021. ; https://doi.org/10.1101/2021.02.02.21250799 doi: medRxiv preprint (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. Vero cells for 20 minutes. Cells were incubated with an anti-SARS-CoV spike primary antibody directly conjugated to biotin (CR3022-biotin) for 1 hour at room temperature. Next, the cells were washed three times in PBS and avidin-HRP was added for 1 hour at room temperature followed by three washes in PBS. Foci were visualized using TrueBlue HRP substrate (KPL, # 5510-0050) and imaged on an ELISPOT reader (CTL). Quantification and Statistical Analysis. Antibody neutralization was quantified by counting the number of foci for each sample using the Viridot program 10 . The neutralization titers were calculated as follows: 1 -(ratio of the mean number of foci in the presence of sera and foci at the highest dilution of respective sera sample). Each specimen was tested in duplicate. The FRNT-50 titers were interpolated using a 4-parameter nonlinear regression in GraphPad Prism 8.4.3. Samples that do not neutralize at the limit of detection at 50% are plotted at 10 and was used for geometric mean calculations. All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted February 5, 2021. ; https://doi.org/10.1101/2021.02.02.21250799 doi: medRxiv preprint Rapid Generation of Neutralizing Antibody Responses in COVID-19 Patients Immunological memory to SARS-CoV-2 assessed for up to eight months after infection Durability of Responses after SARS-CoV-2 mRNA-1273 Vaccination An mRNA Vaccine against SARS-CoV-2 -Preliminary Report Severe Acute Respiratory Syndrome Coronavirus 2 from Patient with Coronavirus Disease, United States Neutralization of N501Y mutant SARS-CoV-2 by BNT162b2 vaccine-elicited sera Development of a Rapid Focus Reduction Neutralization Test Assay for Measuring SARS-CoV-2 Neutralizing Antibodies Rapid Generation of Neutralizing Antibody Responses in COVID-19 Patients Immunological memory to SARS-CoV-2 assessed for up to eight months after infection Durability of Responses after SARS-CoV-2 mRNA-1273 Vaccination An mRNA Vaccine against SARS-CoV-2 -Preliminary Report Severe Acute Respiratory Syndrome Coronavirus 2 from Patient with Coronavirus Disease, United States Neutralization of N501Y mutant SARS-CoV-2 by BNT162b2 vaccine-elicited sera Development of a Rapid Focus Reduction Neutralization Test Assay for Measuring SARS-CoV-2 Neutralizing Antibodies An mRNA Vaccine against SARS-CoV-2 -Preliminary Report An Infectious cDNA Clone of SARS-CoV-2 Viridot: An automated virus plaque (immunofocus) counter for the measurement of serological neutralizing responses with application to dengue virus