ITGA2B and autoimmune thrombocytopenic purpura: Membrane glycoprotein complexes GPIb-IX, including as GPIbα, GPIbβ, GPIX, and GPIa, are recognized by anti-megakaryocyte antibodies in combination with the GPIIb/IIIa complex, commonly referred to as CD41/CD61, which is present in ITP patients [65].