IL-27 Ra/WSX-1/TCCR Fc Chimera Protein, Human

The interleukin-27 receptor subunit alpha (IL27RA), also known as WSX-1 or TCCR, is a member of the type I cytokine receptor family that forms the interleukin-27 receptor heterodimer together with glycoprotein 130 (IL6ST/gp130). Structurally characterized by three fibronectin type-III domains, IL27RA is highly expressed in lymphoid tissues including spleen, lymph nodes, and peripheral blood leukocytes, with particularly strong expression in resting/naive CD4+ and CD8+ T cells.Functioning as the specific ligand-binding component for interleukin-27, IL27RA requires association with gp130 for effective signal transduction through STAT1 and STAT3 pathways. This receptor system plays crucial roles in both adaptive and innate immunity. In adaptive immunity, it promotes Th1-type immune responses by initiating Th1 cell differentiation through STAT1 activation and T-bet expression induction, while also stimulating proliferation of naive CD4+ T cells. In innate immunity, IL27RA contributes to innate defense mechanisms through direct actions on cells of the innate immune system. The receptor shares structural and sequential homology with the IL-12 receptor β2 chain, placing it within the IL-6/IL-12 cytokine family, and serves as a key regulator in bridging innate and adaptive immune responses.