IL-7 treatment did not significantly increase the frequency of MAIT cells expressing TNF-α or granzyme B in COVID-19 patients (Figure S3A,D,C,F), but it successfully increased both the perforin expression level (MFI) (p = 0.001, Fig. 2E,F) and the frequency of MAIT cells expressing perforin (p = 0.001, Fig. 2G,H). This evidence concerns the gene PRF1 and COVID-19.