Representative histology of carotid artery.

Typical adjacent carotid cross-sections taken straight upstream (US), straight downstream (DS) and within the cuff 8 weeks after implantation, stained for HE, Mac-3/MRP14, MMP-2 and MMP-9. HE staining (first row) shows extensive plaque formation, large foam cells (circle) and a narrowed vessel lumen (number sign) in contrast to relatively mild plaque formation in the DS region. Inside the cuff no plaque formation is visible. Magnifications of the same plaque region from different US sections (dashed boxes) demonstrate red stained MRP14-positive cells (arrow heads) close to an area positive for MMP-2 (section sign) and MMP-9 (asterisk sign). In the MRP14/Mac-3 stained DS section open arrow heads line a stripe of plaque deposition positive for Mac-3 (brownish stain). (Scale bar = 150 𝜇m).