Recent studies have implicated the involvement of IL-22 in the pathogenesis of autoimmune diseases, such as rheumatoid arthritis, Crohn’s disease, psoriasis and systemic lupus erythematosus [23] and some hematological diseases, such as myelodysplastic syndrome (MDS) and idiopathic thrombocytopenic purpura (ITP) [24,25]. Here, IL22 is linked to autoimmune disease.