YAP-IRGM1 REGULATES HEPATIC INFLAMMATION IN ORTHOTOPIC LIVER TRANSPLANTATION

项目总结/摘要 肝缺血再灌注损伤（IRI）是肝移植、肝切除、肝移植中常见的问题， 和冲击.由于它经常导致原发性移植物功能障碍（PGD）、晚期慢性排斥反应，并有助于维持移植物的功能。 由于可用于移植的供体器官短缺，肝脏IRI是迄今为止最具挑战性的器官之一。 临床原位肝移植（奥尔特）的并发症研究不足。作为内在雅普表达 与人奥尔特中肝功能和组织损伤呈负相关，用雅普激活剂治疗 通过抑制巨噬细胞功能和改善肝细胞保护来改善肝脏IRI， 肝“温”IRI的非移植模型。在这里，不同的雅普信号通路的功能被提出， 在临床相关的肝冷缺血继奥尔特的小鼠模型中的研究。假设： 下调的移植物周围雅普表达是移植物损伤和PGD发展的重要驱动因素， 雅普在移植肝中的表达降低可能具有预后和治疗意义。蜂窝 特异性雅普分布，促使提出了巨噬细胞（先天性）雅普信号传导的剖析 免疫）调节炎症（致病性）、自噬重编程（稳态）和细胞保护 （抗氧化）在冷储存的鼠OLT中的IR应激期间。提出了以下三个具体目标： 目的1：确定下调的巨噬细胞雅普表达是否是发展中的危险因素。 冷藏小鼠OLT中的PGD？根据初步数据，转基因小鼠品系（YAPM-KO）将 用于评价OLT前和OLT后驻留和循环巨噬细胞上雅普表达与 在临床相关的小鼠模型中，延长肝脏冷藏，然后进行奥尔特。 目的2：阐明雅普信号通路调控免疫相关GT3家族的调控机制 IR应激OLT中的M成员1（IRGM 1）依赖性巨噬细胞炎症。假设：雅普 活化通过偶联环GMP-AMP合酶（cGAS）和 干扰素调节因子3（IRF 3），其反过来通过减少先天性促炎因子而减轻肝脏IRI。 应答将在IRI-OLT中筛选YAP介导的IRGM 1剥夺。然后，建立了一种新的肝脏IRI模型， CD 11b-DTR小鼠，其中过继转移独特的巨噬细胞群体（在条件性消耗 天然CD 11b+细胞）将用于剖析肝脏IR-炎症中的YAP-IRGM 1交叉调节。 目的3：确定雅普控制IRGM 1依赖性巨噬细胞自噬的分子机制 在IR应激OLT中。假设：雅普缺陷增强IRGM 1介导的巨噬细胞自噬， 导致IRI-OLT中肝细胞恶化。YAP-IRGM 1介导的主要自噬体形成 调节巨噬细胞M1/M2平衡，以及IRGM 1衍生的生物学意义和机制 在IR-应激的YAP无效OLT中评估巨噬细胞极化。

PROJECT SUMMARY/ABSTRACT Hepatic ischemia and reperfusion injury (IRI) remains a common problem in liver transplant, hepatic resection, and shock. As it often leads to primary graft dysfunction (PGD), late chronic rejection, and contributes to the shortage of donor organs available for transplantation, liver IRI represents one of the most challenging yet understudied complications in clinical orthotopic liver transplantation (OLT). As intrinsic YAP expression negatively correlated with liver function and tissue damage in human OLT, treatment with YAP activator ameliorated liver IRI by depressing macrophage function and improving hepatocyte protection in a non-transplant model of hepatic “warm” IRI. Here, the function of distinct YAP signaling pathways is proposed to study in a clinically relevant mouse model of prolonged hepatic cold ischemia followed by OLT. Hypothesis: downregulated peri-transplant YAP expression is an important driver of graft injury and development of PGD, and that such reduced YAP expression in liver graft may be of prognostic and therapeutic significance. Cellular specific YAP distribution, has prompted to put forth a dissection that YAP signaling at the macrophage (innate immune) regulates inflammation (pathogenic), autophagic reprogramming (homeostatic) and cytoprotection (anti-oxidative) during IR-stress in cold-stored murine OLTs. The following three specific aims are proposed: Aim 1: Determine whether downregulated macrophage YAP expression is a risk factor for developing PGD in cold-stored murine OLTs? Based on preliminary data, genetically modified mice strain (YAPM-KO) will be used to evaluate pre-OLT and post-OLT YAP expression on residential and circulation macrophage in relation to PGD events in a clinically relevant mouse model of extended hepatic cold storage followed by OLT. Aim 2: Define regulatory mechanisms by which YAP signaling controls immunity-related GTPase family M member 1 (IRGM1)-dependent macrophage inflammation in IR-stressed OLTs. Hypothesis: YAP activation modulates macrophage IRGM1 in liver IRI by coupling cyclic GMP-AMP synthase (cGAS) and interferon regulatory factor 3 (IRF3), which in turn mitigates liver IRI by diminishing innate pro-inflammatory responses. YAP-mediated IRGM1 deprivation will be screened in IRI-OLTs. Then, a new model of liver IRI in CD11b-DTR mice in which adoptive transfer of distinctive macrophage populations (after conditional depletion of native CD11b+ cells) will be utilized to dissect YAP–IRGM1 cross-regulation in hepatic IR-inflammation. Aim 3: Define molecular mechanisms by which YAP controls IRGM1-dependent macrophage autophagy in IR-stressed OLTs. Hypothesis: YAP deficiency augments IRGM1-mediated macrophage autophagy and leads into hepatocellular deterioration in IRI-OLT. YAP–IRGM1 mediated major autophagosomal formation in governing macrophage M1/M2 balance, and the biological significance and mechanisms of IRGM1-derived macrophage polarization will be assessed in IR-stressed YAPnull OLTs.