Recent evidence indicates that IL-22 plays an important role in the pathogenesis of autoimmune diseases, including psoriasis, systemic lupus erythematosus, multiple sclerosis, rheumatoid arthritis, and allergic diseases, implicating Th22 cells and IL-22 as potential therapeutic targets in autoimmune diseases [11,45]. Here, IL22 is linked to systemic lupus erythematosus.