CD8A and COVID-19: Frequency of antigen-specific CD154+CD69+CD8+ T cells did not differ between COVID-19+ and UN individuals but remained higher in early convalescence and decreased with increasing convalescence period (Figure 2H,I, Supplementary Figure S7A); HLA-DR+CD38+ hyperactivated CD8+ T cells also negatively correlated with convalescence (Figure 2J,K, Supplementary Figure S7A).