Figure 3.

In vivo stent endothelialization at day 7 post-implantation. Representative examples of scanning electron microscopy imaging of the luminal surface of pig coronary arteries implanted with either bare metal or drug-eluting stent vs. CD31-mimetic plasma aminated or dip-coated stents (n = 9 stents/group), taken at low (top), medium (middle) or high (bottom) magnification. Arrowheads point at the absence of endothelialization over the drug-eluting stent struts. Note the presence of activated leukocytes (numerous pseudopods at their surface) tangled in a dense fibrin mesh over the endothelialized struts of bare metal stents. Non-activated (round-shaped) leukocytes can be identified over drug-eluting stent struts but there endothelial cells appeared detached one from another and covered with platelets and fibrin. Instead, the absence of leukocyte activation (round shape) was combined with the presence of a smooth and continuous endothelium, free from platelets and fibrin, over CD31-mimetic stent struts.