Leukocyte surface antigen CD47 (CD47)

Leukocyte surface antigen CD47, commonly known as CD47, is a ubiquitously expressed 50 kDa transmembrane glycoprotein belonging to the immunoglobulin superfamily [3, 12]. It serves as a critical "don't eat me" signal by interacting with signal-regulatory protein alpha (SIRPα) on the surface of myeloid cells, such as macrophages and dendritic cells [1, 4]. This interaction triggers an inhibitory signaling pathway that prevents the phagocytosis of healthy host cells, thereby maintaining self-tolerance and homeostatic balance [10, 13]. However, many types of cancer, including both hematologic malignancies and solid tumors, exploit this mechanism by overexpressing CD47 to evade immune surveillance and clearance [6, 11]. Therapeutic strategies targeting the CD47-SIRPα axis, such as monoclonal antibodies and SIRPα-Fc fusion proteins, aim to block this inhibitory signal and promote the macrophage-mediated destruction of tumor cells [8, 16]. Despite its therapeutic potential, the broad expression of CD47 on normal tissues, particularly red blood cells and platelets, poses significant clinical challenges, including treatment-induced anemia and thrombocytopenia [9, 15].

Other names

Integrin-associated proteinIAPMER6OA3Antigenic surface determinant protein OA3Rh-related antigenCD47 molecule

Blockade of the CD47-SIRPα interaction to promote macrophage-mediated phagocytosis (antibody-dependent cellular phagocytosis) and enhance innate and adaptive immune responses against target cells.