CD226 belongs to the Ig-superfamily containing 2 Ig-like domains of the V-set. CD226 is a 65kDa glycoprotein expressed on the surface NK cells, platelets, monocytes and a subset of T cells. CD226 facilitates cellular adhesion of platelets and megakaryocytic cells to vascular endothelial cells. CD226 also plays a role in megakaryocytic cell maturation.