Histological comparison of diseased and normal aortic valve leaflets – All scale bars are 50 μm in length. (A, B): Hematoxylin & Eosin shows thickening and foam cell accumulation in diseased valve leaflets compared to normal valve leaflet (C). (B) shows bone formation at the base of a diseased aortic valve leaflet. The diseased valve leaflet contains extensive macrophage infiltration (D) and smooth muscle actin-positive myofibroblasts (E). Endothelial staining (PECAM) shows microvasculature within diseased valve leaflet (F). Macrophage, smooth muscle actin, and PECAM stains were negative in normal aortic valve (data not shown). ανβ3 integrin stain shows angiogenesis in diseased valve leaflet with highly upregulated expression of ανβ3 (G), while there is minimal expression in the healthy valve leaflet (H).