Incorporating hepatic cell function into lung ex vivo lung perfusion for transplant preservation

针对NHLBI“NOT-HL-21-024”的摘要重新提交1R21 HL164436-01 大胆而新颖的生物工程研究 与其他器官相比，供肺移植的保存时间限制为 标准冷藏时间不超过8小时。质量随时间延长而下降 保存时间增加了原发移植物功能障碍的风险，这是发生移植物功能障碍的风险因素 慢性排斥反应，这可能是肺移植后5年存活率低(50%)的原因 移植(LTX)。体外活体肺灌流有望改善肺保存 通过提供常温循环和通风来提高移植效果。一个问题是， 目前的EVLP受到常温激活的肺代谢的自我限制。积攒的 有毒代谢产物导致促炎状态，激活晚期糖基化受体 最终产物(RAGE)和核因子(NF)-B机制，这反过来又上调 促炎症细胞因子信号转导。实验上，全猪与EVLP的交叉循环 其他人证明了肺复苏的改善，但真正促成这一点的是 改善情况仍不明朗。自身体外初步数据表明肝功能在 加强内皮细胞的保存。在以前的工作中，我们维持了正常的肝脏 使用肝细胞生物反应器(BRX)的体外电路中的解毒、合成和调节。我们 首先假设肝功能在猪跨循环模型中起主要作用 在增强EVLP和组织活力方面。我们还假设，肝细胞BRX可以部分地 在EVLP上替代全猪肝功能并维持观察到的肺功能改善 保存和LTX结果。我们的具体目标是为能力提供原则性证明 肝细胞BRX，以加强肺移植物保存。我们将在我们的 建立EVLP环路及其对实验大鼠短期LTX的影响 模特们。我们将使用身体人的EVLP模型重复这些实验。我们将进行 肺组织的全面表型、转录和功能终点评估 和肝细胞，如RAGE和NF-B。如果成功，我们的技术将提供 改变EVLP的当前状态以保存肺并允许维持肺的手段 供体体外时间更长，细胞损伤更少。最终，我们的工作将解决当前 LTX的局限性，包括增加可行的供体器官运输时间和距离， 帮助减少LTX等待名单，并提高移植后患者的存活率。

ABSTRACT RESUBMISSION 1R21 HL164436-01 IN RESPONSE TO NHLBI “NOT-HL-21-024 BOLD AND NEW BIOENGINEERING RESEARCH” In contrast with other organs, preservation times of lung grafts for transplantation are limited to no more than 8 hours with standard cold preservation. Declining quality with extending preservation times increases the risk of primary graft dysfunction, a risk factor for developing chronic rejection, which could account for the low 5-year survival rate (50%) following lung transplantation (LTx). Ex Vivo Lung Perfusion (EVLP) is expected to improve lung preservation and transplant outcomes by providing normothermic circulation and ventilation. A problem is that current EVLP is self-limited by normothermia-activated lung metabolism. The accumulation of toxic metabolites leads to a proinflammatory state, activating Receptor of Advanced Glycation End-Products (RAGE) and nuclear factor (NF)-B mechanisms, which in turn upregulate proinflammatory cytokine signaling. Experimentally, cross-circulation of a whole swine with EVLP by others demonstrated improved lung resuscitation, but the exact contributors to this improvement remain unclear. Own in vitro preliminary data suggest a role for hepatic function in enhancing endothelial preservation. In previous work, we have maintained normal hepatic detoxification, synthesis, and regulation in in vitro circuits using liver cell bioreactors (BRx). We hypothesize first that the liver function in the swine cross-circulation model played a major role in enhancing EVLP and tissue viability. We also hypothesize that a hepatocyte BRx can partly substitute for whole-swine liver function on EVLP and maintain the observed improvements lung preservation and LTx outcomes. Our Specific Aim is to provide proof-of-principle for the ability of hepatocyte BRx to enhance lung graft preservation. We will incorporate a hepatic BRx in our established EVLP circuits and demonstrate its effect on short-term LTx in experimental rat models. We will repeat these experiments using a cadaveric human EVLP model. We will conduct comprehensive phenotypic, transcriptional, and functional endpoint assessments on lung tissue and hepatic cells in BRx, such as RAGE and NF-B. If successful, our technology will provide the means to change the current state of EVLP for lung preservation and allow lungs to be maintained longer outside the donor body with less cellular injury. Ultimately, our work will address current limitations in LTx, including increasing viable donor organ transportation time and distance, helping reduce LTx waiting lists, and improving post-transplant patient survival.