The phosphorylated acidic glycoprotein osteopontin is present in the extracellular matrix of
atherosclerotic plaques and the wall of injured but not normal arteries. To determine if
osteopontin could serve as a substrate for platelet adhesion, we measured the adherence of
resting and agonist-stimulated human platelets to immobilized recombinant human
osteopontin. Agonist-stimulated but not resting platelets bound to osteopontin by a process
that was mediated primarily by αvμ3. αvμ3-mediated adherence occurred at physiologic …