Rat Anti-Human CD120b Antibody (S-4441)

The CD120b protein, encoded by the TNFRSF1B gene and commonly referred to as TNFR2 or p75, is a key member of the tumor necrosis factor receptor superfamily. As a type I transmembrane protein primarily expressed on immune cells, neurons, and endothelial cells, it binds to the ligand TNF-α and recruits the TRAF2/cIAP1/cIAP2 complex, thereby activating signaling pathways such as NF-κB and PI3K/Akt. This plays a dual role in mediating inflammatory responses, regulating cell survival, and counteracting oxidative stress. Notably, CD120b acts as a "master switch" for regulatory T cells (Tregs): its signaling not only potently promotes Treg proliferation and maintains their immunosuppressive function but is also highly exploited within the tumor microenvironment, driving Treg hyperfunction while simultaneously promoting the proliferation of certain tumor cells—making it a key driver of tumor immune evasion. Additionally, the membrane-bound form of this protein can undergo proteolytic cleavage to generate a soluble fragment (TBP-2), and abnormal levels of this fragment are closely associated with various autoimmune and neuropsychiatric disorders, including systemic lupus erythematosus, rheumatoid arthritis, and schizophrenia. Given its central regulatory role in both immune homeostasis and oncogenesis, antibody-based strategies targeting CD120b present a double-edged sword. Antagonistic antibodies that specifically deplete TNFR2⁺ Tregs within the tumor microenvironment relieve immunosuppression without inducing the widespread autoimmune toxicity often associated with conventional immune checkpoint inhibitors, positioning CD120b as a highly promising next-generation target for cancer immunotherapy.