Description

CD31, a member of the immunoglobulin superfamily,is a 130-kDa transmembrane glycoprotein also designated as PECAM-1 (platelet endothelial cell adhesion molecule. It is present on the surface of platelets, monocytes, macrophages, and neutrophils and is a constituent of the endothelial intercellular junction. It plays a major role in the adhesion cascade between endothelial cell and the inflammatory cells during inflammation in facilitating leucocyte migration and between endothelial cells during angiogenesis .CD31 is expressed by stem cells of the hematopoietic system and is primarily used to identify and concentrate these cells for experimental studies as well as for bone marrow transplantation. Anti-CD31 has shown to be highly specific and sensitive for vascular endothelial cells. Staining of nonvascular tumors (excluding hematopoietic neoplasms) is rare.