CD226 is a 65 kDa glycoprotein expressed on the surface NK cells, platelets, monocytes and a subset of T cells. It is a member of the Ig-superfamily containing 2 Ig-like domains of the V-set. CD226 mediates cellular adhesion of platelets and megakaryocytic cells to vascular endothelial cells. This protein also plays a role in megakaryocytic cell maturation. Recombinant human CD226 protein, fused to His-tag at N-terminus, was expressed in E.coli.