Fig. 2: Neutralizing antibody levels of SARS-CoV-2 convalescents’ sera against the pseudoviruses of SARS-CoV-2 variants.

a The mutations on the spike protein of SARS-CoV-2 variants. The amino acid differences from prototype (including substitution, deletion, and insertion) in sub-variant sequences are highlighted in blueish color. Deletion mutations are shown as blank squares with background color. b–o 50% pseudovirus neutralization titers (pVNT50) against SARS-CoV, SARS-CoV-2 PT, Delta, and Omicron BA.1, BA.2, BA.2.12.1, BA.2.75, BA.4/BA.5/BA.5.2 (n = 20 biologically independent samples in the Control group; n = 60 for BA.2-BTI-3m; n = 60 for BA.2-BTI-6m), XBB, XBB.1.5, CH.1.1, BF.7, BQ.1, and BQ.1.1 (for the last six sub-variants, n = 8 for Control; n = 20 for BA.2-BTI-3m; n = 20 for BA.2-BTI-6m). The Control group is colored in blue. Groups of BA.2-BTI-3m and BA.2-BTI-6m were stratified by time after BA.2 BTI on 2x Convidecia, and colored in red and green separately. The pVNT50 in each group is shown as the geometric mean titers (GMTs) with 95% confidence intervals (CI). GMT numbers are shown on top of each column. The lowest limit of the pseudovirus neutralization assay (1:10) is shown by dashed lines. A pVNT50 < 10 indicated a NAb-negative sample and was counted as 5. P values reflect two-sided ordinary ANOVA tests adjusted for multiple comparisons. Source data are provided as a Source Data file.