New molecule responsible for atherosclerosis

A new molecule called netrin-1 has been found to block the normal migration of macrophages out of arteries, which causes immune cells to accumulate and promote the progression of atherosclerosis.

Researchers at New York University revealed why cholesterol-laden, coronary artery disease-causing cells called macrophages, accumulate in artery plaques. Netrin-1 is a molecule created by the accumulation of macrophages in plaques.

Heart attacks and strokes caused by artery plaques that break off and block vessels have high macrophage cell content.

The immune system sends macrophages to clean up cholesterol deposits in arteries, however, once they are filled up with the unhealthy form of cholesterol they get stuck in the arteries, triggering the body's inflammatory response. Until now, the mechanism by which macrophages become trapped has remained unknown.

The experiment, which used florescent tracking technique to label and monitor the movement of macrophage cells in and out of plaques, showed how macrophages were immobilised and retained in plaque by netrin-1 expression. It also demonstrated macrophage emigration from plaque after the deletion of netrin-1.

Posted by Fiona Griffiths