If a mutation site was in the MHC-like domain, the mutation enhanced the MHC decoy function. It challenged the production of antibodies to neutralize these MHC decoy sites. If antibodies could attach to the MHC-like proteins, the antibodies could also bind to MHC proteins. Then the normal MHC antigen presentation function would be affected, and the body would appear autoimmune diseases. It is not a piece of good news for CD4+ T, CD8+ T, NK cells, and other immune cells that can bind to MHC. These immune cells could indiscriminately bind to MHC-like structures of the S protein, and were attacked by ROS from the E protein. Then the immune system could not effectively perform the antigen presentation for the SARS-COV-2 virus protein. It also could not produce the neutralizing antibody effectively. Moreover, the probability of infected cells was killed by immune cells would be significantly reduced.