CD63 (LAMP-3, lysosome-associated membrane protein-3), a glycoprotein of tetraspanin family, is present in late endosomes, lysosomes and secretory vesicles of various cell types. CD63 is also present in the plasma membrane, usually following cell activation. Hence, CD63 has become a widely used basophil activation marker. In mast cells, however, CD63 exposition does not need their activation. CD63 interacts with integrins and affects phagocytosis and cell migration, it is also involved in H/K-ATPase trafficking regulation of ROMK1 channels. CD63 also serves as a T-cell costimulation molecule. Expression of CD63 can be used for predicting the prognosis in earlier stages of carcinomas. CD63 is expressed on activated platelets, and is a lysosomal membrane glycoprotein that is translocated to plasma membrane after platelet activation. CD63 is also present in monocytes and macrophages and is weakly expressed on granulocytes, B, and T cells. CD63 is identical to the melanoma-associated antigen which is ME491 and to the platelet antigen PTLGP40. Diseases associated with CD63 dysfunction include melanoma and Hermansky-Pudlak Syndrome.
CD 63; CD63; CD63 antigen; CD63 antigen (melanoma 1 antigen); Granulophysin; LAMP-3; Lysosomal-associated membrane protein 3; lysosome-associated membrane glycoprotein 3; Melanoma-associated antigen ME491; melanoma-associated antigen MLA1; Ocular melanoma-associated antigen; OMA81H; Tetraspanin-30; Tspan-30