Finally, we explored HLA-C expression in one subject at three different time points (Figure 5D): T0 before SARS-CoV-2 infection and T1 and T2 after COVID-19 recovery (both at a clinical point of view and negative to SARS-CoV-2 test), the last day of hydroxychloroquine treatment (T1) and 18 days after treatment (T2). This evidence concerns the gene HLA-C and COVID-19.