Regarding anti-S1-specific CD8+ T cells, more COVID-19-naive young participants developed AIM+CD8+ T cells than COVID-19-naive older adults (76.4% versus 48.0%, respectively, p = 0.0018) (Figure 6A), but the frequency of AIM+CD8+ among total CD8+ T cells was similar in responders of both groups (Figure 6B). Here, CD8A is linked to COVID-19.