ENDOTHELIAL CELL TRANSPLANTATION AND AV GRAFT HEALING

动静脉瘘移植物（AVG）在人体中失败是因为 流动表面的血栓形成和细胞的发展 增生 我们以前的研究集中在改变移植物 自体脂肪微血管移植致血栓性 内皮细胞（MVEC）的聚合物移植物的管腔表面上。 我们已经观察到MVEC移植或“草皮化”导致 在聚合物上加速形成抗血栓形成细胞衬里 动脉搭桥手术中使用的移植物。 我们还观察到 MVEC植入动脉旁路术的统计学显著改善 移植物通畅性的动物研究，并已开始使用这项技术， 人体临床试验 MVEC草皮技术在AV中的应用评价 瘘管移植是我们工作的合理延伸。 的 在美国人群中维持AVG通畅率代表了 巨大的医疗成本。 因此，理解 导致AVG失败的机制，以及开发一个过程， 延长AVG开放性将具有直接的人类益处。 为此我们 建议测试四个假设解决MVEC草皮平均在一个 犬模型。 该假设检验将为以下问题提供答案： 以下问题： 1. AVG的MVEC sodding是否改善了通畅性。 2. 移植细胞的密度、细胞类型和细胞移植方法 沉积影响抗血栓形成衬里的形成速率， 后续移植物通畅性？ 3. 微血管内皮细胞的生长是否影响内膜增生的发展？ 4. 它们是细胞增殖的时间序列， 内膜增生 该顺序是否受到MVEC草皮的影响？ 为了解决这些问题，我们将使用犬动静脉瘘模型， 评价增生和生长的细胞和分子方法学 因子表达式 膨胀型PTFE移植物将采用自体 MVEC分离自镰状韧带脂肪。 第一阶段研究将 评价MVEC覆盖对AVG通畅性的影响。 随后的研究 将评估细胞密度和所用细胞类型的影响， 对于sodding（EC vs平滑肌细胞）， 新生内膜 移植物将立即由以下人员进行解释和评价： 形态学和分子生物学技术。 血管移植物环 也将被放置在器官培养和细胞增殖中， 将对内膜以及生长因子表达进行定量。 的 第二阶段研究将通过以下方法评价新生内膜的发展： 在48小时到26周的时间内移植移植物。 通过这些实验，我们提出，以确定如何MVEC草皮 影响抗血栓新生内膜的形成， 临床上观察到的AV通路移植物的慢性增生是 受MVEC草皮技术的影响。

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.