CD47， also known as integrin-associated protein (IAP)， is a member of the immunoglobulin superfamily containing a five-pass transmembrane attachment. CD47 is heavily glycosylated and widely expressed by hematopoietic and nonhematopoietic cells. CD47 interacts with several membrane integrins and also acts a receptor for thrombospondin (THBS1). It is involved in a range of cellular processes， including apoptosis， proliferation， adhesion， and migration. CD47 also functions as a ligand for signal regulatory protein-α (SIRPα). Upon binding CD47， SIRPα initiates a signaling cascade that results in the inhibition of phagocytosis.