Figure 8.

CD24 mediates the resolving efficacy of 4-phenylbutyric acid (4-PBA)-trained monocytes in atherosclerotic mice. A through C, Male wild-type (WT) C57 BL/6 mice, serving as recipients, were intravenously injected with a single dose of AAV8-mPCSK9-D377Y (5×10¹¹ vector genomes per mouse) and fed with high-fat diet (HFD) for 4 weeks. Bone marrow–derived monocytes (BMMs) from WT C57 BL/6 and Cd24^−/− mice were treated with PBS or 4-PBA (1 mmol/L) for 5 days. PBS- or 4-PBA-polarized monocytes (3×10⁶ cells per mouse) were then adoptively transferred by intravenous injection to HFD-fed recipient mice once a week for 4 weeks. Tissues were harvested 1 week after the last monocyte transfer. A, Representative images of H&E-stained atherosclerotic lesions and quantification of plaque size demonstrated as the percentage of lesion area within aortic root area. Scale bars, 300 µm. B, Representative images of Oil Red O–stained atherosclerotic plaques and quantification of lipid deposition within lesion area. Scale bars, 300 µm. C, Representative images of Picrosirius red–stained atherosclerotic plaques and quantification of collagen content within lesion area. Scale bars, 100 µm. Data were analyzed using 2-way ANOVA followed by Šídák post hoc test (n=10 for each group; biological replicates). Error bars represent means±SEM.