ENDOTHELIAL CELL TRANSPLANTATION AND AV GRAFT HEALING

动静脉瘘移植(AVG)在人类中失败的原因是 流动表面的致凝性与细胞的发育 增生症。我们之前的研究集中在改变贪污上。 自体脂肪源性微血管移植的血栓形成作用 内皮细胞(MVEC)附着在聚合物移植物的管腔表面。 我们观察到，MVEC移植或‘软化’会导致 聚合物表面抗血栓形成细胞衬里的加速形成 动脉搭桥手术中使用的移植物。我们还观察到一个 MVEC动脉搭桥术的统计学显著改善 在动物研究中移植通畅，并已开始将这项技术用于 人体临床试验。微血管内皮细胞涂抹技术在影视手术中的应用 瘘管移植代表了我们工作的合理延伸。这个 在美国人群中保持AVG的通畅性代表着一种 巨大的医疗成本。因此，对 导致AVG故障的机制，以及开发流程以 延长AVG的开放时间将立即给人类带来好处。为此，我们 建议测试四个解决MVEC向AVG过渡的假设 犬类模型。该假设检验将提供以下问题的答案 以下是问题： 1.微血管内皮细胞涂抹AVG是否能改善血管通畅性。 2.移植细胞的密度、细胞类型和细胞培养方法 沉积影响抗血栓形成衬里的形成速度和 随后的移植物再通畅？ 3.微血管内皮细胞贴壁是否影响内膜增生的发生？ 4.它们是细胞增殖的时间序列吗？ 内膜增生症？这一序列是否受MVEC抖动的影响？ 为了解决这些问题，我们将使用犬动静脉瘘模型和 细胞和分子方法学评价细胞增殖和生长 因子表达式。扩张型聚四氟乙烯移植物将采用自体移植 从镰状韧带脂肪中分离出MVEC。第一阶段研究将 评价微血管内皮细胞涂抹对动静脉络膜血管通畅率的影响。后续研究 将评估细胞密度和使用的细胞类型的影响 用于抑制血管内皮细胞和血管内皮细胞的生长 新生内膜。移植物将立即由以下人员解释和评估 形态和分子生物学技术。血管移植物环 也将被放置在器官培养和细胞增殖中 血管内膜和生长因子的表达将被量化。这个 第二阶段的研究将通过以下方式评估新生内膜的发展 移植物移植时间从48小时到26周不等。 通过这些实验，我们建议确定MVEC如何 是否会影响抗血栓形成的新生内膜的形成 临床上使用房室通路移植物观察到的慢性增生 受MVEC涂抹技术的影响。

Arterio-Venous fistulate grafts (AVG) fail in humans because of thrombogenicity of the flow surface and the development of cellular hyperplasia. Our previous studies have concentrated on altering graft thrombogenicity by transplanting autologous fat-derived microvessel endothelial cells (MVEC) onto the luminal surface of polymeric grafts. We have observed that MVEC transplantation or 'sodding' results in the accelerated formation of an antithrombogenic cellular lining on polymeric grafts used in arterial bypass surgery. We also have observed a statistically significant improvement in MVEC sodded arterial bypass graft patency in animal studies and have begun to use this technology in human clinical trials. The evaluation of MVEC sodding technology in AV fistulae grafts represents a logical extension of our work. The maintenance of AVG patency in the american population represents a significant healthcare cost. Accordingly, an understanding of the mechanisms resulting in AVG failure, and development of a process to prolong AVG patency will have immediate human benefits. To this end we propose to test four hypotheses addressing MVEC sodding to AVG in a canine model. This hypothesis testing will provide answers to the following questions: 1. Does MVEC sodding of AVG improve patency. 2. Does the density of cells transplanted, cell type and methods of cell deposition affect the rate of formation of an antithrombogenic lining and subsequent graft patency? 3. Does MVEC sodding affect the development of intimal hyperplasia? 4. Is their a temporal sequence of cellular proliferation occurring in intimal hyperplasia? Is this sequence affected by MVEC sodding? To address these questions we will use a canine A-V fistula model and cellular and molecular methodology to evaluate hyperplasia and growth factor expression. Expanded PTFE grafts will be treated with autologous MVEC isolated from falciform ligament fat. First phase studies will evaluate the effects of MVEC sodding on AVG patency. Subsequent studies will evaluate the effects of cell density, and the types of cells used for sodding (EC vs smooth muscle cells) on the development of a neointima. Grafts will be explained and evaluated immediately by morphologic, and molecular biologic techniques. Rings of vascular grafts will also be placed in organ culture and the cellular proliferation in the intima as well as growth factor expression will be quantified. The second phase studies will evaluate the development of the neointima by explanting grafts during periods ranging from 48 hours to 26 weeks. Through these experiments we propose to determine how MVEC sodding influences the development of an antithrombogenic neointima and whether the chronic hyperplasia observed clinically with AV access grafts is affected by MVEC sodding technology.