Stent-Based Delivery of Tissue Inhibitor of Metalloproteinase-3 Adenovirus Inhibits Neointimal Formation in Porcine Coronary Arteries

Abstract

Background— Stent-based antiproliferative therapy appears to decrease in-stent restenosis. However, alternative approaches might produce equivalent efficacy with better long-term safety. In previous work, an adenovirus capable of expressing the tissue inhibitor of metalloproteinase-3 (RAdTIMP-3) inhibited neointima formation in cell cultures and porcine saphenous vein grafts. RAdTIMP-3 decreased smooth muscle cell migration, stabilized the extracellular matrix, and uniquely promoted apoptosis. The current study developed eluting stent technology to deliver RAdTIMP-3 during stenting of pig coronary arteries. Methods and Results— Binding of virus to and elution from stents and transduction of pig coronary arteries were confirmed using β-galactosidase as a reporter gene in vitro and in vivo. Deployment of RAdTIMP-3–coated stents increased apoptosis and reduced neointimal cell density, but did not increase inflammation or proliferation compared with β-galactosidase–expressing adenovirus (RAd lac Z). Neointimal area after 28 days was significantly reduced to 1.27±0.19 mm ² with RAdTIMP-3 versus 2.61±0.31 mm ² with RAd lac Z stents ( P 2 with bare stents ( P Conclusions— Our results demonstrate for the first time to our knowledge the feasibility of adenovirus-coated stent technology and highlight the potential of TIMP-3 to produce significant inhibition of in-stent neointima formation.