Fig. 2

Humoral immune response. Anti-receptor-binding domain (RBD) (A) IgG, (B) IgA, (C) IgM, and (D) neutralizing antibody responses in the serum of macaques after the first and second immunizations, administered 28 days apart, with 15 µg of CoVLP with and without CpG 1018 or AS03. The geometric mean (GMT) and 95% CI are represented. The presence of identical color-matched letters indicates the absence of significant differences between two timepoints for each group (p < 0.05). Significant differences among groups at each timepoint are indicated by # (#p < 0.05, ##p < 0.01, ###p < 0.001, and ####p < 0.0001). Two-way ANOVA of log-transformed optical density (450 nm) values (GraphPad Prism v8, San Diego, USA)