The biology of P-selectin glycoprotein ligand-1: Its role as a selectin counterreceptor in leukocyte-endothelial and leukocyte-platelet interaction

Cell-cell interactions mediating leukocyte trafficking, thrombogenesis and inflammation are crucial for the host defense mechanism. The selectin famil y of integral membrane proteins includes E-selectin, L-selectin and P-selec tin. Selectins mediate tethering and rolling: of leukocytes to the vessel w all at the site of inflammation. The counter-receptor for P-selectin and po ssibly the other selectins is P-selectin glycoprotein ligand-l (PSGL-1). Th is review focuses on the properties and biology of PSGL-1.