Alexa Fluor® 647 Mouse Anti-Human CD152 Antibody (S-R577)

CD152 is a 223-amino-acid transmembrane glycoprotein receptor expressed mainly on activated CD4+ and CD8+ T cells that functions as a critical negative regulator of immune responses by out-competing CD28 for binding to the costimulatory ligands CD80 (B7-1) and CD86 (B7-2) on antigen-presenting cells, thereby transducing inhibitory signals that attenuate T-cell proliferation, cytokine production, and cell cycle progression; the protein’s signal peptide is cleaved to yield a disulfide-linked homodimer whose extracellular Ig-like V-type domain mediates high-avidity ligand engagement, while its cytoplasmic tail contains a tyrosine-based motif that recruits phosphatases such as SHP-2 and PP2A to propagate inhibitory cascades, and genetic polymorphisms or therapeutic blockade of CD152 (e.g., the monoclonal antibody ipilimumab) can enhance antitumor immunity but also precipitate autoimmune toxicities, underscoring its pivotal role in maintaining immune homeostasis.