Abstract 47: Point-of-Care Seeded Blood-Derived Endothelial Cells Rapidly Endothelialize Nitinol Stent in a Pig Model of Personalized Cell Therapy

• Published in: Arteriosclerosis, thrombosis, and vascular biology Vol. 34; no. suppl_1
• Main Authors: Mills, James S, Jantzen, Alexandra E, Baker, Katherine, Lin, Fu-Hsiung, Truskey, George A, Achneck, Hardean E
• Format: Journal Article
• Language: English
• Published: 01.05.2014
• ISSN: 1079-5642; 1524-4636
• DOI: 10.1161/atvb.34.suppl_1.47

Abstract only Intimal hyperplasia after percutaneous intervention is especially problematic in peripheral arteries. In coronary arteries, drug-eluting stents (DES) have greatly reduced intimal hyperplasia; however, DES not only prevent smooth muscle cell proliferation but also inhibit endothelial cell (EC) healing. In an effort to rapidly endothelialize Nitinol vascular stents, we have developed a novel rapid seeding technology (QuickSeeding). 5000 micropores (~32.4 ± 0.4 μm) were laser-drilled circumferentially into Nitinol stent delivery systems to enable ECs to flow across the stent struts and thereby attach to the stent while in its compressed state within 5 min at the point-of-care. To evaluate EC adhesion after stent deployment, ECs were isolated from human umbilical cord blood progenitor cells and QuickSeeded, resulting in a uniform stent surface coverage of 55,000 ± 9,500 cells/cm2 (n=4). QuickSeeded stents were then deployed in tubing and tested in a flow circuit at 15 dynes/cm2, representing arterial flow shear stress. After 48 hr of flow, ECs had spread over the stent surface, demonstrated by PECAM staining of cell junctions. To assess EC function, total nitrite was measured as a marker of NO production and increased from 0.41 ± 0.13 nmol under static conditions to 7.83 ± 1.97 nmol after 24 hr of flow (p<0.05, n=5). These results demonstrate a flow-dependent increase in NO secretion. To test this technology in a large animal model, ECs were grown out from peripheral blood circulating progenitor cells of 4 pigs, fluorescently labeled, and seeded onto 4 stents. The 4 stents were then percutaneously implanted into the carotid arteries of the original 4 pigs. Each pig received an identical uncoated stent in the contralateral artery as control. Fluorescent microscopy and SEM showed that control stents were devoid of ECs but QuickSeeded stents were endothelialized after 2 days. Functionality of ECs adhering to stent struts was confirmed with a metabolic assay after explantation.