CD40-CD40L interactions in atherosclerosis.

Increasing evidence supports a central role for CD40-CD40L interactions in the pathogenesis of atherosclerosis. Recently, we have shown that CD40L deficiency as well as pharmacological inhibition of CD40L in ApoE(-/-) mice results in the development of a stable atherosclerotic plaque phenotype. This phenotype is rich in smooth muscle cells and collagen, and contains only a small amount of macrophages and T-lymphocytes. CD40 and CD40L protein are present in almost all cell types in human atherosclerotic lesions. Expression was observed in early plaques, but was more predominant in advanced, rupture-prone, and ruptured plaques. Because most of the acute complications of atherosclerosis are the result of plaque rupture, CD40L inhibition might be a novel therapeutic approach to prevent atherosclerotic plaque destabilization and plaque rupture.