EPC Adhesion to Teflon-AF and ePTFE Vascular Grafts

描述(由申请人提供)：虽然有许多手术替代自体大直径血管移植物，即同种异体移植物、异种移植物和合成血管移植物替代品，但没有临床上可以接受的替代健康的自体小直径(&lt；6 mm)动脉或静脉。这种缺乏替代品的原因是腔内血栓形成和新生内膜增生阻塞了替代的小直径血管。在小直径血管移植物的管腔内种植一层完整的内皮细胞是提高移植物通畅性的一种有前途的方法。在这项研究中，我们假设体外内皮化小直径ePTFE血管移植物的临床成功取决于三个相互作用的因素的汇合：(1)内皮细胞的自体来源，(2)内皮细胞层与移植物管腔的附着、生长和保持，以及(3)内皮细胞层维持抗血栓的特性。此次竞争性更新的具体目的是：(1)鉴定从冠状动脉疾病患者的外周血中分离出的血源性自体内皮祖细胞，(2)转人血栓调节蛋白(HTM)基因的内皮细胞，(3)验证种植在Teflon AF血管移植物代理膜上的天然和HTM转基因内皮细胞抗血栓标志物的黏附和表达，(4)验证天然和HTM转基因EPC在直径1 mm的ePTFE血管移植物上的黏附和表达，以及(5)检测以天然EPC和HTM转基因EPC接种的ePTFE血管移植物的短期通畅性。将对人类内皮祖细胞进行研究，以期在未来的临床应用中应用。公共卫生相关性：虽然有许多手术替代自体大直径血管移植物，即异体移植物、异种移植物和合成血管移植物替代品，但没有临床上可以接受的替代健康的自体小直径(&lt；6 mm)动脉或静脉。我们认为，在合成的小直径ePTFE血管移植物的管腔内种植一层完整的自体内皮细胞将为缺乏合适的健康自体组织的患者提供一种可行的替代方案。

DESCRIPTION (provided by applicant): While there are a number of surgical alternatives to autologous large diameter vascular grafts, i.e. allografts, xenografts, and synthetic vascular graft substitutes, there are no clinically acceptable alternatives to healthy autologous small diameter (<6mm) artery or vein. This lack of alternatives arises from luminal thrombosis and neointimal hyperplasia that occlude the substitute small diameter vessel. Growing a layer of intact endothelium in the lumen of small diameter vascular grafts represents a promising means of increasing graft patency. In this study we hypothesize that the clinical success of in vitro endothelialized small diameter ePTFE vascular grafts is dependent upon the confluence of three interacting factors: (1) the autologous sourcing of ECs, (2) the attachment, growth and retention of the layer of ECs to the graft lumen, and (3) the maintenance of an antithrombotic profile by the layer of ECs. The specific aims of this competitive renewal are to (1) identify a reliable and viable source of blood-derived autologous EPCs isolated from the peripheral blood of adults with coronary artery disease, (2) transfect the EPCs with the gene for human thrombomodulin (hTM), (3) verify the adherence and expression of antithrombotic markers in native and hTM transfected EPCs seeded onto vascular graft surrogate films of Teflon AF, (4) verify adherence and expression of antithrombotic markers in native and hTM transfected EPCs sodded onto the lumen of 1 mm diameter ePTFE vascular grafts, and (5) test short term patency of ePTFE grafts sodded with native or hTM transfected EPC in nude rats. Human EPCs will be studied in anticipation of future clinical applications. PUBLIC HEALTH RELEVANCE: While there are a number of surgical alternatives to autologous large diameter vascular grafts i.e. allografts, xenografts, and synthetic vascular graft substitutes, there are no clinically acceptable alternatives to healthy autologous small diameter (<6mm) artery or vein. We propose that growing a layer of intact, autologous endothelium in the lumen of small diameter ePTFE vascular grafts synthetic would provide a viable alternative for patients who lack suitable healthy autologous tissue.