TNF and autoimmune thyroid disease: Th17 cells secrete proinflammatory cytokines such as Interleukins IL-17A, IL-21, IL-22, tumor necrosis factor (TNF)-α, and IL-6 (4–6), playing pivotal roles in host defense and in the pathogenesis of autoimmune diseases including autoimmune thyroid disease (7) systemic lupus erythematosus and multiple sclerosis (5, 6, 8–10).