One contributor to the build-up of fatty plaques in artery walls is a signalling protein that blocks the emigration of a major plaque constituent from the deposits.

Fat-laden white blood cells called macrophages are abundant in atherosclerotic plaques. Kathryn Moore at New York University and her colleagues found that these cells produce netrin-1, a protein that can guide the migration of white blood cells and the growing tips of neurons. But expression of netrin-1 in plaques blocked macrophage responses to chemical cues that would normally direct them out of the plaques.

Furthermore, mice lacking the netrin-1 gene had less atherosclerosis. These findings suggest that netrin-1 could provide a new drug target.

Nature Immunol. http://dx.doi.org/10.1038/ni.2205 (2012)