Figure 4.

Comparison of the magnitude of CD4+ (left) and CD8+ (right) T-cell responses against SARS-CoV-2 S, M, and N proteins between the different subgroups at baseline (BL) and after two doses of vaccine (PV, post-vaccination). No CR (unexposed without cross-reactivity, green dots and bars), CR (unexposed with cross-reactivity, rose dots and bars), and Conv (convalescent, red dots and bars). Frequencies are indicated at the X axis. Statistically significant when p < 0.05. * = p < 0.05, and *** = p < 0.001.