The AK-4 monoclonal antibody specifically reacts with human CD62P （P-Selectin）, a 140 kDA type I transmembrane glycoprotein also known as platelet activation-dependent granule membrane protein （PADGEM）.
Upon activation it is quickly transported to the plasma membrane from the alpha-granules of platelets and WEibel-Palade bodies of endothelial cells.
It is essential to the functions of cell adhesion during inflammatory reactions and in the interaction of platelets with monocytes and neutrophils.
