Th17 cells: a new therapeutic target in inflammatory dermatoses.

Th17 cells, named for their secretion of interleukin-17 (IL-17), are a new class of T-cells involved in a wide range of cutaneous autoimmune and inflammatory conditions. An overactive Th17 cell response in the skin can produce damaging results. There appears to be a partial role for the Th17 axis in the pathogenesis of a range of dermatological diseases including allergic contact dermatitis, atopic dermatitis, psoriasis, and scleroderma. Immunologists have also discovered a unique association between Th17 cells and cutaneous T-cell lymphoma. The Th17 branch has been linked to a number of additional systemic inflammatory diseases with significant cutaneous pathology such as systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease, and Behcet's disease. Newly developed treatment modalities for neutralizing the Th17 branch of the immune system are proving to be valuable additions to the current therapeutic armamentarium.