Figure 1. Humoral immune response to the Gam-COVID-Vac in 149 elderly individuals. (A) A cross-sectional study of IgG anti-RBD titers measured by ELISA in serum samples taken at 0, 14, 28, 60, 90 and 180 days’ post-vaccination (dpv). CP: SARS-CoV-2 Convalescent plasm (n = 309) analyzed with the same ELISA platform [