Human Recombinant IL-5

Interleukin 5 (IL-5) is a member of the short-chain 4-α-helical bundle subset of hematopoietic cytokines. It binds to a receptor consisting of IL-5Ra, which is specific for IL-5R, and common beta chain, which is shared with the receptor for IL-3 and GM-CSF (Shearer). Upon binding to its receptor, IL-5 activates the JAK/STAT and MAPK pathways. IL-5 is produced by Th2 cells, eosinophils, and activated mast cells. It functions in the recruitment, activation, proliferation, and survival of eosinophils, thus playing an important role in allergic inflammation, asthma, and parasite immunity. Stimulation of eosinophils with IL-5 leads to their activation, upregulation of CD11b expression, and inhibition of apoptosis (Shearer).