APOE and atherosclerosis: With the use of an atherosclerosis model in apolipoprotein E knock out (ApoE−/−) mice, Zhang X et al. have reported that systemic infusion of human GMSC to ApoE-/- mice significantly reduced the plaque size and lipid deposition in the wall of blood vessels, the frequency of inflammatory monocytes/macrophages, and macrophage foam cell formation.