Background：CD61 is a membrane glycoprotein with a molecular weight of 105 kDa, it is expressed in platelets, megakaryocytes, osteoclasts and vascular endothelial cells. CD61 can react with integrin-b3, then integrin-b3 binds to the glycoprotein llA （CD41） and form the CD41/CD61 complex （GP lib/llla） to regulate the conglutination and accumulation of platelet. CD61 is mainly used for identification of platelet and its precursor cells, and can be applied in diagnosis of megakaryocytic leukemia.
