Effect of Anti-ApoA-I Antibody-Coating of Stents on Neointima Formation in a Rabbit Balloon-Injury Model

<div><p>Background and Aims</p><p>Since high-density lipoprotein (HDL) has pro-endothelial and anti-thrombotic effects, a HDL recruiting stent may prevent restenosis. In the present study we address the functional characteristics of an apolipoprotein A-I (ApoA-I) antibody coating <i>in vitro</i>. Subsequently, we tested its biological performance applied on stents <i>in vivo</i> in rabbits.</p><p>Materials and Methods</p><p>The impact of anti ApoA-I- versus apoB-antibody coated stainless steel discs were evaluated <i>in vitro</i> for endothelial cell adhesion, thrombin generation and platelet adhesion. <i>In vivo</i>, response to injury in the iliac artery of New Zealand white rabbits was used as read out comparing apoA-I-coated versus bare metal stents.</p><p>Results</p><p>ApoA-I antibody coated metal discs showed increased endothelial cell adhesion and proliferation and decreased thrombin generation and platelet adhesion, compared to control discs. In vivo, no difference was observed between ApoA-I and BMS stents in lumen stenosis (23.3±13.8% versus 23.3±11.3%, <i>p</i>=0.77) or intima surface area (0.81±0.62 mm² vs 0.84±0.55 mm², <i>p</i>=0.85). Immunohistochemistry also revealed no differences in cell proliferation, fibrin deposition, inflammation and endothelialization.</p><p>Conclusion</p><p>ApoA-I antibody coating has potent pro-endothelial and anti-thrombotic effects <i>in vitro</i>, but failed to enhance stent performance in a balloon injury rabbit model <i>in vivo</i>.</p>