SARS-CoV-2 vaccination of convalescents boosts neutralization capacity against SARS-CoV-2 Delta and Omicron that can be predicted by anti-S antibody concentrations in serological assays
التفاصيل البيبلوغرافية
العنوان:
SARS-CoV-2 vaccination of convalescents boosts neutralization capacity against SARS-CoV-2 Delta and Omicron that can be predicted by anti-S antibody concentrations in serological assays
BackgroundRecent data on immune evasion of new SARS-CoV-2 variants raise concerns about antibody-based COVID-19 therapies. Therefore in this study the in-vitro neutralization capacity against SARS-CoV-2 variants Wuhan D614G, Delta and Omicron in sera of convalescent individuals with and without boost by vaccination was assessed.Methods and FindingsThis in-vitro study included 66 individuals with a history of SARS-CoV-2 infection, divided into subgroups without (n=29) and with SARS-CoV-2 vaccination (n=37). We measured SARS-CoV-2 antibody concentrations by serological assays (anti-SARS-CoV-2-QuantiVac-ELISA (IgG) and Elecsys Anti-SARS-CoV-2 S) and neutralizing titers against Wuhan D614G, Delta and Omicron in a pseudovirus neutralization assay.Sera of the majority of unvaccinated convalescents did not effectively neutralize Delta and Omicron (4/29, 13.8% and 19/29, 65.5%, resp.). Neutralizing titers against Wuhan D614G, Delta and Omicron were significantly higher in vaccinated compared to unvaccinated convalescents (pin-vitro by Bamlanivimab, Casirivimab and Imdevimab, Omicron was resistant to these monoclonal antibodies.ConclusionsThese findings confirm substantial immune evasion of Delta and Omicron which can be overcome by vaccination of convalescents. This informs strategies for choosing of plasma donors in COVID-19 convalescent plasma programs that shall select specifically vaccinated convalescents with very high titers of anti-S antibodies.
