Human IL9

IL9 (interleukin-9) interacts selectively with IL-9 R which then associates with gamma c to form the functional receptor complex. It is expressed by activated Th9, Th17, Treg, and Th2 cells, and acts as an autocrine growth and activation factor for Th17, Treg, and mast cells. IL-9 contributes to allergic inflammation, autoimmunity-induced inflammation, parasite clearance from the GI tract, and Treg-mediated immune suppression. It enhances the expansion and recruitment of mast cells and eosinophils as well as the production of IgE and Th2 cytokines.