Interleukin-9 Simoa

Interleukin 9 (IL-9) is predominately produced by T lymphocytes, specifically T helper 9 (Th9) cells. IL-9 plays a role in immunity and inflammation directly affecting the function/activity of multiple cell types including T cells, mast cells, and airway epithelial cells. IL-9 signaling via binding to the IL-9 receptor which results in the formation of a heterodimeric complex with the common gamma chain. Receptor dimerization activates JAK1 and JAK3 leading to the activation of STAT1, STAT3, and STAT5 transcription factor proteins and subsequent modulation of gene expression. Th9 cells are well known to play a role in triggering allergic inflammation and asthma and promoting autoimmune diseases such as idiopathic pulmonary fibrosis, Crohn?s disease, multiple sclerosis, systemic lupus erythematosus, and rheumatoid arthritis. Elevated serum IL-9 levels were shown to correlate with disease severity in asthma. Th9 cells are also reported to promote immune tolerance and protect against parasitic infections. More recently, Th9 cells have been shown to exert anti-tumor immunity.

Swiss-Prot Accession Number: P15248