FIGURE 2.

Multiple functions of SARS‐CoV‐2 S1 protein. S1 protein interacts with some active receptors/molecules expressed on many cell types, by directly or indirectly interfering with innate and adaptive immune responses. S1 protein induces also HLA‐E expression on epithelial cells mediated by GATA3 activation which may negatively affect NKG2A+ NK cells in the lung. S1 protein display also epitopes with superantigenic activity and/or cross‐reacting with self‐antigens: They may amplify polyclonal activation of not specific T cells or bystander autoreactive T and B cells