EPC Adhesion to Teflon-AF and ePTFE Vascular Grafts

描述（由申请人提供）：虽然有许多外科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，但没有临床可接受的替代健康的自体小直径（<6mm）动脉或静脉。由于管腔血栓形成和新生内膜增生阻塞了替代的小直径血管，导致缺乏替代血管。在小直径血管移植物的管腔内培养一层完整的内皮细胞是增加移植物通畅的一种有希望的方法。在本研究中，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因素的融合：(1)内皮细胞的自体来源，(2)内皮细胞层在移植物腔内的附着、生长和保留，以及(3)内皮细胞层维持抗血栓特性。这种竞争性更新的具体目的是：(1)从患有冠状动脉疾病的成人外周血中分离出一种可靠和可行的血液来源的自体EPCs，(2)用人血栓调节蛋白（hTM）基因转染EPCs，(3)验证天然和hTM转染的EPCs在Teflon AF血管移植替代膜上的粘附性和抗血栓标志物的表达。(4)在直径1mm的ePTFE血管移植物的管腔中，验证转染了天然ePTFE和hTM的EPCs的粘附性和抗血栓标志物的表达；(5)在裸鼠身上检测转染了天然ePTFE或hTM的ePTFE移植物的短期通畅性。人类EPCs将在未来的临床应用中进行研究。公共卫生相关性：虽然有许多外科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，但临床无法接受健康的自体小直径（<6mm）动脉或静脉的替代品。我们建议在小直径ePTFE血管移植物的管腔中生长一层完整的自体内皮，为缺乏合适的健康自体组织的患者提供可行的替代选择。

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.