Alexa Fluor® 647 Mouse Anti-Human CD50 Antibody (S-4993)

CD50, also known as Intercellular Adhesion Molecule 3 (ICAM-3), is a type I transmembrane glycoprotein belonging to the immunoglobulin superfamily that plays a pivotal role in the initiation and regulation of immune responses, particularly during the early stages of T-cell activation. Primarily expressed on the surface of leukocytes, including resting T cells, B cells, monocytes, and granulocytes, CD50 functions as a critical ligand for the leukocyte function-associated antigen-1 (LFA-1, or CD11a/CD18) integrin found on antigen-presenting cells and other immune effectors. This interaction facilitates stable adhesion between immune cells, thereby supporting essential processes such as immunological synapse formation, leukocyte migration, and costimulatory signaling that primes naive T cells for subsequent activation by ICAM-1 and other molecules. Beyond its adhesive properties, CD50 is involved in intracellular signal transduction pathways that influence cell morphology and cytoskeletal rearrangement, making it a key mediator in both innate and adaptive immunity, with its dysregulation implicated in various inflammatory disorders and hematological malignancies.