However, IL-17-producing cells have an important role in the development of several autoimmune diseases in humans such as systemic lupus erythematosus [40], rheumatoid arthritis [41], bronchial allergy [21], inflammatory bowel disease [20], multiple sclerosis [42], and Kawasaki disease [43] and also in experimental models such as collagen-induced arthritis [19] and experimental autoimmune encephalomyelitis (EAE) [22]. This evidence concerns the gene IL17A and multiple sclerosis.