Enforced cell survival promotes atherogenesis in the absence of CX₃CR1. Quantitative analysis of atherosclerotic lesion area in apoe^−/− recipients of wt (○) and cx₃cr1^gfp/gfp (●) BM cells, either from hMRP8bcl2-transgenic (hBcl2 tg) or nontransgenic (non tg) donors. Mice were subjected to high-fat diet for 12 weeks, after which atherosclerotic plaques were analyzed in aortic roots (A,A') and en face prepared aortas (B,B′) by Oil Red O staining. Panels A′ and B′ show a summary of Oil Red O⁺ plaque area for each group, a representative of which is shown in panels A and B, respectively; n = 12, representative of 2 independent experiments. *P < .05, **P < .01 (Student t test).