key: cord-0696763-zdkntuay
authors: Marot, Stéphane; Malet, Isabelle; Jary, Aude; Leducq, Valentin; Abdi, Basma; Teyssou, Elisa; Soulie, Cathia; Wirden, Marc; Rodriguez, Christophe; Fourati, Slim; Pawlotsky, Jean-Michel; Boutolleau, David; Burrel, Sonia; Calvez, Vincent; Marcelin, Anne-Geneviève
title: Neutralization heterogeneity of United Kingdom and South-African SARS-CoV-2 variants in BNT162b2-vaccinated or convalescent COVID-19 healthcare workers
date: 2021-03-05
journal: bioRxiv
DOI: 10.1101/2021.03.05.434089
sha: f594236633ba1b3e5bb5eb6ddf808a87d113e153
doc_id: 696763
cord_uid: zdkntuay

There are concerns about neutralizing antibodies (NAb) potency against the newly emerged VOC202012/01 (UK) and 501Y.V2 (SA) SARS-CoV-2 variants in mRNA-vaccinated subjects and in recovered COVID-19 patients. We used a viral neutralization test with a strict 100% neutralizing criterion on UK and SA clinical isolates in comparison with a globally distributed D614G SARS-CoV-2 strain. In two doses BNT162b2-vaccinated healthcare workers (HCW), despite heterogeneity in neutralizing capacity against the three SARS-CoV-2 strains, most of the sera harbored at least a NAb titer ≥ 1:10 suggesting a certain humoral protection activity either on UK or SA variants. However, six months after mild forms of COVID-19, an important proportion of HCW displayed no neutralizing activity against SA strain. This result supports strong recommendations for vaccination of previously infected subjects.

ABSTRACT 23 There are concerns about neutralizing antibodies (NAb) potency against the newly emerged 24 VOC202012/01 (UK) and 501Y.V2 (SA) SARS-CoV-2 variants in mRNA-vaccinated subjects 25 and in recovered COVID-19 patients. We used a viral neutralization test with a strict 100% 26 neutralizing criterion on UK and SA clinical isolates in comparison with a globally distributed 27 D614G SARS-CoV-2 strain. In two doses BNT162b2-vaccinated healthcare workers (HCW), 28 despite heterogeneity in neutralizing capacity against the three SARS-CoV-2 strains, most of 29 the sera harbored at least a NAb titer ≥ 1:10 suggesting a certain humoral protection activity 30 either on UK or SA variants. However, six months after mild forms of COVID-19, an important 31 proportion of HCW displayed no neutralizing activity against SA strain. This result supports 32 strong recommendations for vaccination of previously infected subjects. UK and 501Y.V2 for SA) [3, 4] . The spreading of these variants has increased rapidly in other 50 countries and recent observations suggests that they are significantly more transmissible than 51 previously circulating variants. It is still not fully known if the pathogenicity is either increased, Written informed consent for participation in this study was obtained from all participants. 

Virus neutralization test 95 The neutralizing activity of the various serum specimen was assessed with a whole virus 96 replication assay as previously describe (9). Microscopy examination on day 4 to assess the 97 cytopathic effect (CPE). Neutralization antibody (NAb) titers are expressed as the highest 98 serum dilution displaying 100% inhibition of the CPE. A same known positive control serum 99 was added to each experiment to assess the reproductivity. All the serum samples were tested for their neutralizing activity against SARS-CoV-2 D614G, (13/25) of HCW harbored neutralizing activity with a NAb titer ≥ 1:5 against the D614G strain, 117 24% (6/25) were neutralizing against the UK strain and only two (8%) had detectable NAbs 118 against the SA strain (Figure 1 A, Table S1 ). Seven days after the booster immunization, all but I7  10  5  0  I8  10  20  5  I9  20  20  5  I10  40  20  5  I11  80  80  20  I12  40  40  0  I13  20  20  5  I14  80  20  10  I15  160  40  20  290 

Mutated COVID-19 may foretell a great risk for mankind in the future

Tracking Changes in SARS-CoV-2 Spike: Evidence that D614G

rapid spread of a new severe acute respiratory syndrome-related 198 coronavirus 2 (SARS-CoV-2) lineage with multiple spike mutations in South Africa | 199 medRxiv

Preliminary genomic characterisation of an emergent SARS-CoV-2 lineage in the UK 201 defined by a novel set of spike mutations -SARS-CoV-2 coronavirus / nCoV

Covid-19: New UK variant may be linked to increased death rate, early 206 data indicate

Neutralization of SARS-CoV-2 spike 69/70 deletion, E484K and N501Y variants by