ML1 monocytes had preferential expression of Ccr5, Cd72, Trem2, and Spp1, while ML2 monocytes had higher expression of Ccr2, Cd74, and Ly6c. Although mechanisms responsible for their divergent polarization are not clear, their generation may represent coordinated low-grade inflammatory events relevant to the pathogenesis of chronic diseases such as atherosclerosis. This evidence concerns the gene SPP1 and atherosclerosis.