Platelet and endothelial cell P-selectin and its leukocyte sialoglycoprotein ligand

P-selectin (CD62P) belongs to the selectin family of cell adhesion molecules, which includes E-selectin (CD62E) and L-selectin (CD62L). It contains a NH2-terminal domain of similar to 120 amino acid residues homologous to Ca2+-dependent animal lectins and functions as an inducible receptor on activated platelets and endothelial cells for most leukocytes. The high-affinity human leukocyte ligand for P-selectin is dimeric transmembrane sialomucin, called PSGL-1 (P-selectin Glycoprotein Ligand-1). As this molecule also serves as a ligand for E-selectin, we refer to it as P/ESGL-1 (P- and E-selectin Glycoprotein Ligand-1). There is an increasing body of evidence from work both in vitro and in vivo to support an important physiological and pathological role for P-selectin in mediating adhesion of leukocytes to endothelial cells and platelets in inflammation.