P-selectin is a protein that in humans is encoded by the SELP gene.
P-selectin functions as a cell adhesion molecule on the surfaces of activated endothelial cells, which line the inner surface of blood vessels, and activated platelets. In unactivated endothelial cells, it is stored in granules called Weibel-Palade bodies, and α-granules in unactivated platelets.
Other names for P-selectin include CD62P, Granule Membrane Protein 140, and Platelet Activation-Dependent Granule to External Membrane Protein. It was first identified in endothelial cells in 1989.