A recent report investigating TREM2 in macrophages in atherosclerosis proposed that TREM2 promotes lipid uptake and macrophage survival and that TREM2 deficiency in macrophages decreases lesion formation17, thereby showing TREM2-mediated modulation of macrophage functions consistent with our observations but contrasting outcomes of in vivo disease readouts. This evidence concerns the gene TREM2 and atherosclerosis.