Th17 cells, a key player in autoimmune diseases and antibiosis, are differentiated from naïve T cells (CD4+) stimulated by IL-6, TGF-β, IL-1β, IL-21 and IL-23 [43–46] and release IL-17A, IL-17F, IL-21 and IL-22. The gene discussed is IL23A; the disease is autoimmune disease.