Additionally, the regulatory role of NKG2D in COVID-19 is also supported by Lee et al., 2022 where their results show that the viral non-structural protein 1 (Nsp1) of SARS-CoV-2 mediates its immune escape by downregulating NKG2D ligands, therefore decreasing NKG2D-dependent NK cytotoxic responsiveness and conferring resistance to infected cells. This evidence concerns the gene KLRK1 and COVID-19.