Strong Correlations between the Binding Antibodies against Wild-Type and Neutralizing Antibodies against Omicron BA.1 and BA.2 Variants of SARS-CoV-2 in Individuals Following Booster (Third-Dose) Vaccination

• DOI: 10.3390/diagnostics12081781
• Publication Date: 2022-07-22T16:53:45Z
• Authors: Nungruthai Suntro...; Suvichada Assawak...; Sitthichai Kanokudom; Ritthideach Yorsaeng; Chompoonut Auphimai; Thanunrat Thongmee; Preeyaporn Vichai...; Thaneeya Duangchinda; Warangkana Chantima; Pattarakul Pakcho...; Jira Chansaenroj; Pornjarim Nilyanimit; Donchida Srimuan; Thaksaporn Thatsa...; Natthinee Sudhina...; Nasamon Wanlapakorn; Juthathip Mongkol...; Yong Poovorawan
• Keywords: Antibody titer

This study examined the neutralizing activity and receptor-binding domain (RBD) antibody levels against wild-type omicron BA.1 BA.2 variants in individuals who received three doses of COVID-19 vaccination. The relationship between anti-RBD IgG live virus titers was examined. In total, 310 sera samples from after booster vaccination (third-dose) were tested for specific SARS-CoV-2 RBD surrogate neutralization test (sVNT). assay performed using foci-reduction (FRNT50). strongly correlated with FRNT50 BA.2. Non-linear regression showed that at cut-off value ≥148 BAU/mL ≥138 related to threshold ≥20 BA.2, respectively. A moderate correlation observed sVNT titers. At ≥20, predicted ≥10.57% ≥11.52%, identified predict detectable antibodies variants. Assessment monitoring protective immunity support vaccine policies will help identify optimal timing