Additionally, Cell Atlas analysis revealed that proteins with increased HLA-I peptides were most enriched for liver markers, consistent with a high incidence of liver injury in severe COVID-19 cases, while proteins with reduced HLA-I peptides were enriched for CD4+ and CD8+ T cell markers, consistent with the reduced T cell counts that has been observed in patients with severe COVID-19 (23) (Figure 2E; Table S7). This evidence concerns the gene CD8A and COVID-19.