TLR2 and autoimmune disease: TLR2 is widely investigated in the pathogenesis of autoimmune diseases including rheumatoid arthritis [44–46], systemic lupus erythematosus [47, 48], systemic sclerosis [49], Sjogren’s syndrome [50–52], psoriasis [53, 54], multiple sclerosis [55, 56], and autoimmune diabetes [57, 58].