As presented in Figure 6A, compared with the control samples, naïve B cells, follicular helper T cells, Tregs, activated NK cells, monocytes, and activated mast cells were less enriched, while plasma cells, CD4 naïve T cells, activated CD4 memory T cells, γδ T cells, resting dendritic cells, and activated dendritic cells were more enriched in COVID-19 sample. The gene discussed is CD4; the disease is COVID-19.