P-selectin 

P-selectin (CD62) is a type 1 transmembrane protein encoded by the selectin-P (SELP) gene in humans. It is produced in megakaryocytes and endothelial cells and is packaged in platelet α-granules and endothelial Weibel-Palade bodies. Upon stimulation, P-selectin rapidly mobilizes to the cell surface and is then externalized. Just as rapidly, P-selectin can be re-internalized and destroyed or recycled. The major ligand for P-selectin is P-selectin glycoprotein ligand-1 (PSGL-1), which is present on most leukocytes. P-selectin also binds platelet glycoprotein (Gp)1b, promoting leukocyte and platelet rolling and adhesion. P-selectin also triggers the release of procoagulant microparticles and increases tissue factor expression on monocytes.