Figure 5.

Spike-RBD-specific cells induced by SARS-CoV-2 vaccination over time. (A) Timeline for blood draws for analysis of nAbs in plasma, the secretion from stimulated PBMCs, or cellular identification with the MiSelect R II. T4 was 4 weeks after a 3rd vaccination, while T5 was a blood draw 6 months later. (B) Concentration of neutralizing anti-spike-RBD IgG antibodies in plasma samples from vaccinated subjects over time. (C) Total number of spike-RBD-specific MBCs in PBMC samples from all vaccinated subjects for each time point. (D) Concentration of neutralizing anti-spike-RBD IgG antibodies in culture supernatant over time from PBMC stimulated with R848, IL-2, IL-21, sCD40, and WT-RBD. The error bar indicates the median. Statistics were calculated using the non-parametric Mann–Whitney test. The dotted line indicated the limit of detection (LOD) for the assay. * p < 0.05; ** p < 0.01; *** p < 0.001; ns, no significant difference.