Interleukin-12 receptor (IL-12R) (IL-12R)

The Interleukin-12 receptor (IL-12R) is a heterodimeric type I cytokine receptor complex composed of two subunits, IL-12Rβ1 and IL-12Rβ2 (UniProt: P42701, Q99665). It is primarily expressed on activated T cells and natural killer (NK) cells, but is also found on dendritic cells, where it mediates the signaling of the pro-inflammatory cytokine IL-12 (PubMed: 15123770). Upon binding of IL-12, the receptor activates the JAK-STAT signaling pathway, specifically involving JAK2, TYK2, and the phosphorylation of STAT4 (StatPearls: Interleukin 12). This process is crucial for the differentiation of naive CD4+ T cells into Th1 cells and the subsequent production of interferon-gamma (IFN-γ), which are essential components of the adaptive immune response against intracellular pathogens (PubMed: 9565861). Dysregulation or overactivation of the IL-12/IL-12R axis is implicated in the pathogenesis of several chronic inflammatory and autoimmune diseases, including psoriasis, Crohn's disease, and ulcerative colitis (PubMed: 22126727). Conversely, genetic mutations in the receptor subunits can lead to Mendelian Susceptibility to Mycobacterial Diseases (MSMD), characterized by severe infections from weakly virulent mycobacteria (NCBI: NBK1154). Therapeutic targeting of this pathway is achieved by monoclonal antibodies such as ustekinumab, which binds to the p40 subunit shared by IL-12 and IL-23, thereby preventing their interaction with the IL-12Rβ1 subunit and modulating the inflammatory cascade (FDA: Stelara Label).

Other names

IL-12 receptor complexIL12RInterleukin-12 receptor subunit beta-1Interleukin-12 receptor subunit beta-2

Inhibition of IL-12 signaling by blocking the p40 subunit of the IL-12 ligand, preventing receptor activation.