Following 3 months of HCD feeding, atherosclerosis developed (Supplemental Fig. 9b, c), and blood and aortas were analyzed by flow cytometry for CD45.1/CD45.2 chimerism and differences in the expression of proliferation marker Ki67 in CD45.1 Msr1+/+ versus CD45.2 Msr1–/– macrophages, and in CD45.1 CD36+/+ versus CD45.2 CD36–/– macrophages, respectively. This evidence concerns the gene MSR1 and atherosclerosis.