The MH9A3 monoclonal antibody specifically binds to human interleukin-9 (IL-9). Human IL-9 is a multifunctional cytokine and a member of the type I cytokine (hematopoietin) family that includes IL-2, IL-4, IL-7, IL-15 and IL-21. This cytokine is encoded by the IL9 gene that is resident on chromosome 5q31.1. IL-9 is expressed by activated CD4-positive T helper cells, by some transformed T cells and by eosinophils, mast cells and neutrophils. IL-9 induces the proliferation, differentiation, and effector function of various cell types including T lymphocytes, B lymphocytes, mast cells, eosinophils, neutrophils, hematopoietic cells and epithelial cells. It potentiates the interleukin-4-induced IgM, IgG and IgE responses by human B lymphocytes. IL-9 has been implicated in human allergic disorders such as asthma and malignancies such as Hodgkin's disease. IL-9 exerts its biological activities through binding to the surface IL-9 receptor (IL-9R) complex comprised of the IL-9R alpha subunit (IL-9Rα; CD129) and the common cytokine receptor gamma subunit (γc; CD132). IL-9 signaling through its receptor includes activation of the Janus kinases 1 and 3 ( JAK1 and JAK3) and activation of Signal transducer and activator of transcription 1, 3 and 5 factors (STAT1, STAT3 and STAT5).
This antibody is conjugated to BD Horizon PE-CF594, which has been developed exclusively by BD Biosciences as a better alternative to PE-Texas Red®. PE-CF594 excites and emits at similar wavelengths to PE-Texas Red® yet exhibits improved brightness and spectral characteristics. Due to PE having maximal absorption peaks at 496 nm and 564 nm, PE-CF594 can be excited by the blue (488-nm), green (532-nm) and yellow-green (561-nm) lasers and can be detected with the same filter set as PE-Texas Red® (eg, 610/20-nm filter).