IL12Rbeta2

IL12Rbeta2, also known as IL12RB2 or IL12RB, is a receptor subunit that plays a crucial role in the immune system. It is a type I transmembrane protein that primarily binds to the cytokine interleukin-12 (IL-12). This receptor is a component of the high-affinity IL-12 receptor, which is a heterodimer consisting of IL12Rbeta2 and the IL12Ralpha subunit (IL12RA). The IL12Rbeta2 subunit itself is a distinct protein that associates with other receptor chains to form functional receptors.

The expression of IL12Rbeta2 is predominantly found on T helper 1 (Th1) cells, natural killer (NK) cells, and dendritic cells. Upon binding of IL-12 to the IL12Rbeta2 subunit, a signaling cascade is initiated. This signaling pathway often involves the Janus kinase (JAK) family of tyrosine kinases, particularly JAK2, and signal transducer and activator of transcription (STAT) proteins, most notably STAT4. Activation of STAT4 is a key event downstream of IL-12 signaling.

The biological consequences of IL-12Rbeta2 engagement by IL-12 are significant. It is critical for the differentiation of naive T cells into Th1 cells, which are important for cell-mediated immunity against intracellular pathogens. IL-12 signaling through IL12Rbeta2 also promotes the production of interferon-gamma (IFN-gamma) by Th1 and NK cells, further enhancing immune responses. Dysregulation of IL12Rbeta2 function has been implicated in various autoimmune diseases and inflammatory conditions, highlighting its importance in maintaining immune homeostasis.

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