However, the function of MAIT cells has significant duality and tissue specificity—in microenvironments such as the intestines, lungs, or liver, it can secrete IL‐22 to promote tissue repair; however, it can also be converted into a proinflammatory mediator in autoimmune diseases and metabolic diseases, directly damaging tissues or amplifying pathogenic pathways such as Th17. The gene discussed is IL22; the disease is autoimmune disease.