Atherosclerosis involves the formation of plaques and chronic inflammation in large arteries, which weakens vessel walls and restricts blood flow. PECAM-1 is expressed in many hematopoietic cells and along endothelial cells of the vascular wall, where it binds a subset of myeloid cells and responds to changes in blood flow. In mice with a susceptibility to atherosclerosis (ApoE−/−), Hazel Stevens and colleagues found that removing PECAM-1 reduces the amount and extent of atherosclerotic lesions. The authors speculate that the reduced ability of mutant endothelial cells to sense changes in blood flow causes disease resistance of PECAM-1−/− vessels.
