Inflammation is a complex response involving many different cells and signaling molecules, including the secretion of the cytokine IL-17 by activated T cells. IL-17 secretion is restricted to specific subsets of T cells but the receptor for IL-17 is widely expressed throughout the body, including fibroblasts and epithelial cells. Inflammatory responses involving IL-17 probably contribute to arthritis, asthma, skin immune reactions and autoimmune disorders. Fibroblasts and other cells stimulated by IL-17 are induced themselves to secrete inflammatory and hematopoietic cytokines, including IL-6, IL-8, G-CSF and Stem Cell Factor (SCF). These cytokines in turn provoke a range of activities, including the stimulation of neutrophil proliferation and differentiation.
