ISLET TRANSPLANTATION

胰岛移植

• 批准号: 2142266
• 负责人: HELENA P SELAWRY
• 金额: $ 14.5万
• 依托单位: UNIVERSITY OF TENNESSEE HEALTH SCI CTR
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-04-01 至 1996-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2142266
• 关键词: Macaca mulatta; Sertoli cells; diabetes mellitus therapy; disease /disorder model; electron microscopy; gender difference; glucagon; glucose tolerance test; hormone metabolism; immune tolerance /unresponsiveness; immunosuppression; insulin; insulin dependent diabetes mellitus; male castration; model design /development; pancreatic islet transplantation; radioimmunoassay; testis; transplantation immunology

The central objective of this grant is to develop a technique whereby pancreatic islets can be successfully grafted into a large animal model, the Rhesus monkey, who is homologous to the human in terms of immune responsiveness and testicular morphology. The following specific objectives are planned: Specific aim #1: Determine the optimal amount of islets grafted per testis to achieve a physiologic reversal of the diabetic process. Earlier studies have shown that a total of 10,000 islets per kg grafted into the testes of diabetic primates led to rapid induction of euglycemia which was sustained for more that 100 days. But these animals also showed evidence of hyperinsulinemia, suggesting that the mass injected may have been excessive. Male primates will thus be made diabetic and a comparative study done on the effect of specified and variable amounts of islet cells on induction of normoglycemia. The results will be correlated with weight-corrected islet counts in the grafted tissues. Specific aim #2: Determine the optimal organ site for islet transplantation in the primate. Clinical application of islet transplantation will require the grafting of a large mass of islets into the testes. Theoretically this may not be feasible because of the relatively smaller size of the testis of man compared to that of the primate. But earlier studies revealed that the grafting of islets into the testis of rats with concomitant cyclosporine therapy led to the induction of tolerance in the host. A study will thus be conducted in male primates on the survival of islets transplanted into the livers of animals with a primary testis graft, compared with survival of identical preparations in the livers of naive animals who had never been exposed to islets. Specific aim #3: Design a method for the grafting of female monkeys. Previous studies in rats have shown that isolated Sertoli cells grafted along with islets into the renal subcapsular space of female rats led to augmented islet allograft survival. Consequently a study will be initiated whereby the survival of islets, with and without Sertoli cells, will be examined in the renal, subcapsular space of diabetic, female primates. Specific Aim #4: Determine the effect of established intratesticular islet allografts on glucose homeostasis. Using standard methods for the stimulation of insulin secretion from beta cells, grafted primates will be given IVGTT, OGTT, and sustacal stimulation tests. Serum glucose, insulin and C-peptide levels will be determined and compared with control, and with diabetic, non-transplanted, animals. Specific Aim #5: Examine the effects of intratesticular islet allografts on testis and beta cell morphology. Grafted, normoglycemic animals will be orchiectomized and the tissues prepared for light and electron microscopy. The degree of granulation of beta cells, the relationship of beta cells to testicular cell components, presence or absence of inflammatory reactions, are some of the characteristics which will be assessed. The results of these studies will provide knowledge critical to the long term objective of designing and developing techniques for the transplantation of the human diabetic with isolated pancreatic islets.

这笔赠款的核心目标是开发一种技术，使 胰岛可以成功移植到大型动物模型中， 恒河猴，在免疫方面与人类同源 反应能力和睾丸形态。 具体如下 计划目标：具体目标#1：确定最佳数量 每个睾丸移植胰岛以实现生理逆转 糖尿病过程。 早期研究表明，总共有 10,000 将每公斤胰岛移植到患有糖尿病的灵长类动物的睾丸中会导致快速 诱导血糖正常，持续100多天。 但 这些动物还表现出高胰岛素血症的证据，表明 注射的质量可能过多。 因此，雄性灵长类动物将 进行了糖尿病治疗，并针对特定和特定的效果进行了比较研究 不同数量的胰岛细胞诱导正常血糖。 这 结果将与体重校正的胰岛计数相关 移植组织。 具体目标#2：确定最佳器官部位 灵长类动物的胰岛移植。 胰岛的临床应用 移植需要将大量胰岛移植到 睾丸。 理论上这可能不可行，因为 与男性相比，男性睾丸的尺寸相对较小 灵长类动物。 但早期的研究表明，将胰岛移植到 联合环孢素治疗的大鼠睾丸出现 诱导宿主耐受。 因此将进行一项研究 雄性灵长类动物移植到肝脏的胰岛存活率 具有原发性睾丸移植物的动物与具有相同睾丸移植物的动物的存活率相比 从未接触过的幼稚动物肝脏中的制剂 到小岛。 具体目标#3：设计一种雌性嫁接方法 猴子。 先前对大鼠的研究表明，分离的支持细胞 与胰岛一起移植到雌性大鼠的肾被膜下空间 导致胰岛同种异体移植物存活率增加。 因此一项研究将 启动胰岛的生存，无论是否有支持氏细胞 细胞，将在糖尿病患者的肾脏、囊下空间进行检查， 雌性灵长类动物。 具体目标#4：确定既定目标的效果 睾丸内胰岛同种异体移植物对葡萄糖稳态的影响。 使用标准 刺激移植的β细胞分泌胰岛素的方法 灵长类动物将接受 IVGTT、OGTT 和 Sustacal 刺激测试。 将测定血清葡萄糖、胰岛素和 C 肽水平，并 与对照组以及糖尿病、非移植动物相比。 具体目标#5：检查睾丸内胰岛同种异体移植物的效果 睾丸和β细胞形态。 嫁接的、血糖正常的动物会 切除睾丸并准备接受光和电子的组织 显微镜。 β细胞颗粒化程度、关系 β细胞与睾丸细胞成分的关系，存在或不存在 炎症反应是一些特征， 评估。 这些研究的结果将为长期研究提供至关重要的知识。 设计和开发技术的术语目标 用分离的胰岛移植人类糖尿病患者。