Background information
IL-17 is produced by CD4+ T helper cells, a T cell subset termed Th17, which also secrete IL-17F and IL-22 and express the NK cell marker CD1611 . IL-17 secretion has also been described for other cell types, such as CD8+ memory T cells.
Th17 cells are involved in the recruitment of neutrophils to control early stages of infections by a number of pathogens, such as extracellular bacteria and fungi. IL-17 and Th17 cells play an important role in immune-mediated inflammatory diseases, such as rheumatoid arthritis, psoriasis, multiple sclerosis, asthma, and inflammatory bowel disease.