Ex vivo perfusion in a lung box for rehabilitation of donor lungs

描述(申请人提供)：大多数潜在的供体肺被排斥进行移植，因此许多患者在等待合适的供体时死亡。供体肺通常是在脑死亡后从个体身上取回的；然而，人们对利用心源性死亡后取回的非心脏跳动供体(NHBD)肺重新产生了兴趣。NHBD肺利用的主要挑战是在热缺血后难以评估功能，这会导致严重的损伤。有两种新方法有望极大地扩大NHBD肺的应用：1)使用体外肺灌流(EVLP)的“肺盒”来评估和修复移植前的肺；2)使用腺苷2A受体(A2AR)激动剂来修复肺并防止缺血再灌注(IR)损伤。这项建议结合了这两种方法，完善了一种基于肺盒的EVLP方法，用于评估和治疗NHBD肺移植的成功。我们已经证明了使用A2AR激动剂进行EVLP后NHBD猪肺的康复和成功移植，我们还证明了腺苷2B受体(A2BR)拮抗剂可以减轻IR损伤。因此，我们提出的研究将验证这样的假设，即NHBD肺可以通过使用A2AR激动剂或A2BR拮抗剂的EVLP介导性治疗来恢复以成功移植。我们将通过三个目标来检验这一假设。目的1将使用猪肺移植模型来确定使用A2AR激动剂的EVLP是否可以安全地延长NHBD肺的热缺血和冷缺血时间。AIM 2将确定使用A2AR激动剂的EVLP是否将边缘和先前被排斥的人类供体肺恢复到可接受的移植状态。AIM 3将确定使用A2BR拮抗剂的EVLP是否能恢复猪和人的NHBD肺。在每个目标中，我们还将确定EVLP对NHBD肺的康复是否需要抑制NKT细胞激活、上皮细胞激活和中性粒细胞浸润。该项目解决了困扰肺移植的两个主要问题：适合移植的肺太少，以及移植后由于IR损伤而导致的原发移植物失败。如果NHBD的肺可以安全地修复用于移植，那么肺供体短缺就可以消除。因此，该项目将提供一种手段，极大地扩大供体肺池的规模，并支持旨在挽救更多在肺移植等待名单上的患者的生命的临床试验。

DESCRIPTION (provided by applicant): The majority of potential donor lungs are rejected for transplantation and thus many patients die while waiting for a suitable donor. Donor lungs are typically retrieved from individuals after brain death; however, there is renewed interest in utilizing non-heart- beating donor (NHBD) lungs retrieved after cardiac death. The major challenge for utilization of NHBD lungs is the difficulty in assessing function after a warm ischemic period which results in significant injury. Two novel approaches show promise to greatly expand the utilization of NHBD lungs: 1) use of a "lung box" for ex vivo lung perfusion (EVLP) to assess and rehabilitate lungs prior to transplantation, and 2) use of adenosine 2A receptor (A2AR) agonist to rehabilitate lungs and prevent ischemia-reperfusion (IR) injury. This proposal combines these two approaches to perfect a lung box-based method of EVLP to assess and therapeutically rehabilitate NHBD lungs for successful transplantation. We have demonstrated the rehabilitation and successful transplantation of NHBD porcine lungs after EVLP with an A2AR agonist, and we have demonstrated that an adenosine 2B receptor (A2BR) antagonist attenuates IR injury. Thus our proposed studies will test the hypothesis that NHBD lungs can be rehabilitated for successful transplantation by EVLP-mediated therapy using an A2AR agonist or A2BR antagonist. We will test this hypothesis with three aims. Aim 1 will use a porcine lung transplant model to determine if EVLP with A2AR agonist can safely extend both warm and cold ischemic times of NHBD lungs. Aim 2 will determine if EVLP with A2AR agonist therapy will rehabilitate marginal and previously rejected human donor lungs to an acceptable state for transplantation. Aim 3 will determine if EVLP with A2BR antagonist will rehabilitate porcine and human NHBD lungs. Within each aim, we will also determine if the rehabilitation of NHBD lungs by EVLP entails the inhibition of NKT cell activation, epithelial cell activation and neutrophil infiltration. This project addresses two major problems that plague lung transplantation: far too few suitable lungs for transplant and primary graft failure after transplat due to IR injury. If NHBD lungs can be safely rehabilitated for transplantation, then the lung donor shortage could be eliminated. Thus this project will provide a means to greatly extend the donor lung pool size and support clinical trials aimed at saving many more lives of those patients on the lung transplant waiting list.