We also observed that there was no public TCR clonotype among the different populations of Tregs and across patients with different severities of COVID-19, and there was a higher frequency of TCR sharing between HLA_DR+ Tregs and CD69+ Tregs (Supplementary Figures S6E, F), especially in the MR and SP groups (Figure 6C). The gene discussed is CD69; the disease is COVID-19.