Cellular adhesion molecules and peripheral arterial disease.

Cellular adhesion molecules (CAMs), by mediating the recruitment of circulating leukocytes to the blood vessel wall and their subsequent migration into the subendothelial spaces, play a crucial role in all stages of atherosclerosis. Soluble forms of CAMs, probably derived from proteolytic shedding, are present in the circulation and their blood levels parallel the amount expressed on the cell surface. In patients with peripheral arterial disease (PAD), increased levels of soluble CAMs have been found during exercise-induced claudication, are associated with the presence, the severity and the extent of atherosclerosis in the arteries of the lower limbs, and portend a worse outcome. These findings have provided new insights into the pathophysiology of PAD and its consequences. However, further large population studies are needed to firmly establish whether increased levels of circulating CAMs give additive information to current risk assessment approaches, and to verify whether PAD patients with elevated levels of circulating CAMs would benefit from any specific therapy.