Measurement of the percentage of section covered by plaque was performed every 25 sections (75 μm) through the width of the artery. An average of 6.75 measurements was made per carotid. To standardize the analysis, measurement of plaque coverage was performed on the field of view 500 μm below the carotid bifurcation. This avoids the potential for plaque initiation due to either the turbulent shear stress experienced around the bifurcation or the mechanical damage to CHIR99021 the endothelium during gene transfer. The average length analyzed for

plaque coverage was ∼1400 μm the length of internal elastic lamina. The data was normally distributed within each group, and differences between groups were analyzed using one-way analysis of variance (ANOVA), using Tukey–Kramer multiple comparisons post hoc test. In a separate cohort of mice, gene transfer of either LOX-1 or RAd66 selleck was performed and the mice sacrificed after 7 days. Both the transduced and nontransduced arteries were taken and snap frozen in OCT compound (BDH), orientated to allow transverse sections to be cut. Seven-micrometer-thick frozen sections were cut, air dried, and fixed in methanol with 0.3% H2O2 for 10 min. Human LOX-1 expression was visualized using goat anti-human LOX-1 antibody (5 μg/ml, AF1798, R&D Systems, Abingdon, UK) or matched nonimmune goat control,

with 1/400 biotinylated rabbit anti-goat secondary antibody (DAKO, Ely, UK) and 1/200 extravidin HRP conjugate (Sigma, Poole, UK) with SIGMA FAST diaminobenzidine

staining tablets (Sigma). Sections were counterstained with hematoxylin for 30 s. In order to Ketanserin test the potential of endothelial LOX-1 overexpression to contribute to atherogenesis, we performed luminal gene transfer using an adenoviral vector. Ten-minute luminal incubation of the vector, or an empty virus control (RAd66), was sufficient to achieve gene transfer, detected by immunohistochemistry on transduced vessels (Fig. 1A–C). Only cells on the surface of the lumen stained for human LOX-1, showing that the technique selectively transduces endothelial cells, in agreement with previous reports [18]. To assess the impact of endothelial LOX-1 overexpression on the development of atherosclerosis, carotid arteries were examined 6 weeks following gene transfer, in hyperlipidemic ApoE−/− mice, without the placement of any flow-modifying cuffs or collars. Transduced arteries were removed, opened up, and sectioned longitudinally to allow the area of the vessel surface covered by plaque to be assessed along the vessel (Fig. 1D–F). There was significantly more plaque coverage in arteries transduced by LOX-1 compared to controls, with an average of 91% coverage vs. 50% RAd66 control virus (Fig. 2, P≤.05). Infection with RAd66 alone increased plaque coverage (50% compared to 30%) compared to vehicle, although this failed to reach significance.