Expression studies in aortic tissue of fat-fed mice that received transplants. (A) Immunoblot analysis using the Mac-3 antibody and lysates of cultured cells (NIH 3T3 fibroblasts and macrophages—Mϕ—obtained from the BM of wild-type and p27^–/– mice) and aortic tissue prepared from the pooled descending aortic arch of 3 fat-fed mice. The arrowheads point to macrophage-specific bands. (B) PCNA-immunostained specimens (Figure 1) were analyzed to quantify PCNA-immunoreactive cells per cross-section, both in the media and atheroma. PCNA-positive cells were counted in at least 3 sections from different regions of the aortic arch and all independent values were averaged. The dotted horizontal bars indicate the average value in each group. (C) Real-time quantitative RT-PCR analysis of total RNA isolated from the descending aortic arch to quantify cytokine expression within the atherosclerotic vessel wall. The number of animals in each group is indicated (n). Results are given as mean ± SE (ratio of cytokine/GAPDH [glyceraldehyde-3-phosphate dehydrogenase] mRNA). For each cytokine, average values in both groups were compared using the nonparametric Mann-Whitney U test (*, P < .01; **, P < .001). Error bars indicate SE.