There are different theoretical explanations for the development of autoimmunity in patients with SARS-CoV-2 infection such as: (1) superantigen activity: the S protein of SARS-CoV-2 contains sequence and structure motifs similar to those of a bacterial superantigen and can bind directly to the T-cell receptor; (2) molecular mimicry and overt autoimmunity: accumulating evidence demonstrates that the virus has structural similarity to host-derived components. Here, PROS1 is linked to Autoimmunity.