Description
Interleukin 9, also known as IL9, is a TH2 cytokine1 belonging to the group of interleukins. This cytokine stimulates cell proliferation and prevents apoptosis. It functions through the interleukin-9 receptor (IL9R), which activates different signal transducer and activator (STAT) proteins and thus connects this cytokine to various biological processes. IL-9 stimulates the proliferation of a variety of hematopoietic lineages through its interaction with a receptor of the cytokine receptor superfamily.2 IL-9 plays a role in the complex pathogenesis of bronchial hyperresponsiveness as a risk factor for asthma.3