markers to identify each cluster (Fig. 2I). This approach identified an increase in cells in several clusters including Clusters 1, 2, and 5 in COVID-19 patients, reflecting CD45RA+CD27−CCR7− TEMRA-like populations that expressed CX3CR1 and varying levels of T-bet (Fig. 2, I and J). Clusters 12 and 14 contained CD27+HLA-DR+CD38+KI6