Figure 5. In vivo delivery of the annexin A1 fragment Ac2-26 reduces atherosclerosis.

A–C, Apoe^−/−, Apoe^−/−Fpr2^−/−, and Apoe^−/−Anxa1^−/− mice were fed a high-fat diet (HFD) for 4 weeks. Intravital microscopy of the carotid artery was used for assessment of luminal leukocyte endothelial interactions. Myeloid cells were identified by intravenous injection of an antibody to CD11b 10 minutes before recording. Myeloid cell adhesion (B) and rolling flux (C) in Apoe^−/− (left), Apoe^−/−Fpr2^−/− (middle), and Apoe^−/−Anxa1^−/− (right) mice were assessed before and 30 minutes after injection of native (panels to the left) or boiled Ac2-26 (far right panel; 50 μg, IV). Representative images are shown in A. Scale bar, 100 μm. Each dot represents 1 mouse. *P<0.05 compared with read-out before Ac2-26 administration. Data were analyzed with paired t test. D, Apoe^−/− mice were fed a HFD for 4 weeks and mice received a single dose of antagonist to CCR2 (RS504393, 5 mg/kg), CCR5 (DAPTA, 1 mg/kg), or CXCR2 (SB225002, 5 mg/kg), or a combination of all, or vehicle control. Thirty minutes later arterial adhesion of CD11b⁺ cells was studied (before). Immediately after recording, mice received Ac2-26 (50 μg IV) and adhesion was studied 30 minutes later (after). Each dot represents 1 mouse. *P<0.05 compared with read-out before Ac2-26 administration. Data were analyzed with Wilcoxon matched-pairs signed rank test. E–G, Ac2-26 reduces atherogenesis. Apoe^−/− mice (n=6 per group) were repeatedly injected with Ac2-26 (3× per week; 50 μg IP per injection) or vehicle control during 4 weeks of HFD. E, Quantification of atherosclerotic lesion sizes in Oil-Red-O–stained aortic root sections. Representative images are shown aside. F, Quantification of Mac2⁺ macrophages. G, Quantification of lesional Ly6G⁺ neutrophils. *P<0.05 compared with vehicle treatment. Data in F and G are presented as mean±SD. Data in E–G were analyzed with Mann-Whitney test.