Composite porcine islet-kidney xenotransplants to cure diabetes and renal failure

项目摘要 该实验室以前开发了一种技术，用于移植胰岛作为复合物的一部分， 胰岛-肾（I-K），其中将自体胰岛置于供体动物6至8的肾包膜下 移植前几周。在此期间，胰岛变得血管化，因此没有周期性的血管化。 当随后将I-K移植到受体动物时对胰岛的缺血性损伤。也没有 在此期间，由于免疫反应造成的损伤，因为胰岛是自体的。我们已经证明 该技术对于成功的同种异体胰岛移植优于游离胰岛移植的优点， 在小型猪和非人类灵长类动物身上都有。然而，这种方法对临床胰岛 移植受6至8周血管化要求的限制，因为这一要求限制了移植的成功率。 对活体捐赠者。将该方法扩展到I-K异种移植可以消除这种限制， 为许多患有终末期糖尿病肾病的患者目前未满足的需求提供治疗。直到 然而，最近异种移植肾的存活时间太短，需要的免疫抑制太大， 这种方法被认为是一种可行的临床选择。我们最近的研究表明， 使用小型猪供体和诱导耐受性的药物， approach.因此，本项目的目标是开发一种临床相关的耐受诱导策略 进行猪到狒狒的I-K移植具体而言，我们将：1）将联合收割机IK技术与我们的混合 嵌合耐受诱导方法，以确定肾脏耐受是否延伸至猪胰岛， 2）联合收割机IK加电生理技术，以确定肾脏耐受性是否扩展到 猪胰岛和逆转糖尿病;和3）比较和对比混合嵌合体和嵌合体方法， 对肾脏和胰岛抗原耐受机制的研究。如果成功，我们的方法可以克服 目前通过提供几乎无限的供体供应来治疗这种临床上重要的实体的局限性 胰岛和肾脏，一种耐受性的方法，以避免需要长期，慢性免疫抑制和 来自近交系小型猪的供体肾，具有达到与人相似大小的内在能力 受惠人士

Project Summary This laboratory has previously developed a technique for transplanting pancreatic islets as part of a composite islet-kidney (I-K), in which autologous islets are placed under the kidney capsule of the donor animal 6 to 8 weeks prior to transplantation. During this time, the islets become vascularized, so that there is no period of ischemic damage to the islets when the I-K is subsequently transplanted to a recipient animal. There is also no damage due to an immune response during this period, since the islets are autologous. We have demonstrated the advantages of this technique over free islet transplantation for successful allogeneic islet transplantation, both in miniature swine and in non-human primates. However, the applicability of this approach to clinical islet transplantation is limited by the requirement for 6 to 8 weeks for vascularization, since this requirement limits the approach to living donors. Extension of the approach to I-K xenotransplants could eliminate this limitation, providing a cure for the currently unmet needs of many patients with end-stage diabetic nephropathy. Until recently, however, the survival of xenograft kidneys was too short and the immunosuppression required too great for the approach to be considered as a viable clinical option. Our recent studies now suggest that long-term survival of porcine kidneys in baboons is possible using miniature swine donors and a tolerance-inducing approach. The goal of this project is therefore to develop a clinically relevant tolerance induction strategy for pig-to-baboon I-K transplantation. Specifically, we will: 1) Combine IK technology with our mixed chimerism tolerance-inducing approach to determine whether tolerance of kidney extends to porcine islets and reverses diabetes; 2) Combine IK plus VTL technologies to determine whether tolerance of kidney extends to porcine islets and reverses diabetes; and 3) Compare and contrast mixed chimerism and VTL approaches with regard to mechanism of tolerance to kidney and islets antigens. If successful, our approach could overcome the current limitations to treatment of this clinically important entity by providing a virtually limitless donor supply of islets and kidneys, a tolerance approach to avoid the need for long-term, chronic immunosuppression and a donor kidney from inbred miniature swine, with intrinsic capacity to attain a size similar to that of human recipients.