Next, we found that IL-27 negatively correlated with the CCR6+CD8+ T cell frequencies within EM (r = –0.400, p = 0.006) and TEMRA (r = –0.343, p = 0.021) subsets in patients with acute COVID-19, but not in convalescents COVID-19 or healthy controls (Figure 8B,C, respectively). Here, CCR6 is linked to COVID-19.