This polyclonal antibody is directed against the interleukin 12 (IL-12) subunit IL12B. IL-12 is a key immunoregulatory cytokine that coordinates innate and adaptive immune responses. IL12 is a disulfide-linked heterodimer composed of the 40 kD cytokine receptor like subunit IL12B, and a 35 kD subunit IL12A. IL12 is expressed by activated macrophages that serve as an essential inducer of Th1 cells development. It acts on T and natural killer cells, and has a broad array of biological activities. The main role of IL-12 is activation of Interferon gamma ( IFN-gamma) production by triggering the Jak-STAT signaling pathway. Overexpression of the IL12 gene was observed in the central nervous system of patients with multiple sclerosis (MS), suggesting a role of this cytokine in the pathogenesis of the disease. IL-12 is also linked to autoimmunity. Promoter polymorphisms in the IL12 gene have been reported to be associated with the severity of atopic and non-atopic asthma in children.