P-Selectin, also known as CD62P, GMP-140, PADGEM, and LECAM-3, is a transmembrane adhesion protein that is upregulated on activated platelets and vascular endothelial cells. It binds to hematopoietic cell PSGL-1/CD162 with highly clustered O-linked sialyl Lewis-x (sLex ) tetrasaccharides and sulfated tyrosine, as well as to heparin sulfate, Versican, and CD42b/GPIb alpha. P-Selectin mediates the initial interaction of circulating leukocytes with activated endothelial cells that produces a characteristic ‘rolling’ of the leukocytes on the endothelium. It is therefore critical for leukocyte extravasation at sites of inflammation and leukocyte involvement in thrombus formation at sites of vascular injury.
