Interleukin-12 subunit beta (IL-12p40) (IL-12p40)

Interleukin-12 subunit beta, commonly known as IL-12p40, is a regulatory cytokine subunit that plays a dual role in the immune system by dimerizing with the p35 subunit to form Interleukin-12 (IL-12) and with the p19 subunit to form Interleukin-23 (IL-23) [UniProt: P29460]. IL-12 is essential for the differentiation of naive T-cells into Th1 cells, while IL-23 is crucial for the maintenance and expansion of the Th17 cell population, both of which are central to the inflammatory response [PubMed: 18311140]. These pathways are heavily implicated in the pathogenesis of chronic autoimmune diseases such as psoriasis, Crohn's disease, and ulcerative colitis [NCBI: IL12B]. Therapeutic monoclonal antibodies, such as ustekinumab, target the p40 subunit to simultaneously neutralize both IL-12 and IL-23 signaling, effectively suppressing multi-pathway inflammation [FDA: Stelara Label]. Because IL-12 and IL-23 are involved in host defense, therapeutic inhibition of the p40 subunit is associated with an increased risk of serious infections and potentially malignancy [StatPearls: Ustekinumab]. Despite these safety considerations, IL-12p40 remains a cornerstone target in the treatment of moderate-to-severe immune-mediated inflammatory disorders [PubMed: 25164408].

Other names

IL12B [NCBI: 3593]Cytotoxic lymphocyte maturation factor 2 [UniProt: P29460]CLMF2Natural killer cell stimulatory factor 2NKSF2Interleukin-12 subunit p40IL-23 subunit p40

Binds to the p40 subunit shared by Interleukin-12 (IL-12) and Interleukin-23 (IL-23) cytokines, thereby blocking their interaction with the IL-12Rβ1 receptor protein and inhibiting subsequent Th1 and Th17 mediated inflammatory signaling [PubMed: 18311140].