To assess whether the defect in cholesterol efflux plays a causal role in the accelerated atherosclerosis in M-Jak2 mice, we treated BMDM from M-Jak2 WT and KO mice with an LXR agonist TO901317 which is known to enhance cholesterol efflux through transcriptional upregulation of the cholesterol transporters ABCA1 and ABCG120. This evidence concerns the gene ABCA1 and atherosclerosis.