Macrophage subsets in atherosclerosis

Only M1 proinflammatory and M2 anti-inflammatory macrophages have been described in vitro—however, a wide spectrum of intermediate phenotypes has been identified in in vivo studiesVarious stimuli (cytokines, lipids and their derivatives, senescent cells, iron) can influence macrophage phenotypes in atherosclerotic lesionsMacrophages with different functional phenotypes are likely to perform different roles in the development of atherosclerosisM1 macrophages are associated with symptomatic and unstable plaques, whereas M2 macrophages are particularly abundant in stable zones of the plaque and asymptomatic lesionsModulation of macrophage phenotypes might be a novel strategy for the pharmacological treatment of atherosclerosis