Vein graft lesions show clear neovascularization.

<p><b>A</b>; Endothelial cell staining (CD31) of neovessels in a vein graft lesion. <b>B</b>; Erythrocytes are clearly visible in (*) and outside neovessels indicating that leaky vessels are present. <b>C</b>; VEGF staining of a vein graft with extravasated erythrocytes (*), a VEGF positive neovessel is depicted with #. <b>D</b>; Basement membrane staining with antibodies directed to laminin. Most neovessels in vein grafts stain positive. <b>E:</b> SMC staining of a vein graft.^# marks SMC positive neovessels and * depicts neovessels lacking pericytes. These neovessels without pericytes are frequently found in regions with extravasated erythrocytes. Insets are 10x magnifications of vein grafts.