Innate-Adaptive Immunoregulation in Liver Transplant Ischemia/Reperfusion Injury

项目3--摘要/摘要 缺血再灌注损伤(IRI)是移植过程的必然结果，是限制移植的关键因素。 人肝移植。IRI引起的细胞损伤可导致原发的非功能性必需性 再次移植。肝脏IRI还使受体容易发生急性和慢性排斥反应以及移植物丢失，因为 同时，减少可移植器官的数量。在小鼠模型中的关键观察表明肝脏IRI 是由先天免疫系统和获得性免疫系统共同调节的。目前还不清楚类似的机制是否 在人类肝移植中发挥着重要作用。我们的中心假设是识别阻尼器及其相关的 PRRs在人OLT-IRI期间驱动髓细胞可塑性将使我们能够开发治疗干预措施 改善OLT结果。目的1，我们将确定TLR9和TLR7/NOD2配体介导的差异 炎性巨噬细胞与调节性巨噬细胞的极化以及与T细胞的串扰。我们将描述细胞的特征- 游离DNA/TLR9配体线粒体DNA、中性粒细胞胞外陷阱和HMGB1/RAGE在治疗前后的变化 再灌流血液以确定其对人OLT-IRI的贡献，极化巨噬细胞和发育的能力 同种异体反应T细胞。我们还将确定TLR7和NOD2配体对其调节的耐受作用 可能缓解TLR4和/或TLR9极化和抑制同种异体免疫。特征描述 受者血液和供者移植活组织中髓系和T细胞表型的纵向变化 再灌流前后将确定内型特异性通路上新的靶向相互作用 TLR4/TLR9和TLR7/NOD2原位杂交。目标2将确定PRR预适应的治疗潜力 减轻髓系激活和OLT-IRI。我们将评估TLR4/9拮抗剂的治疗潜力 用血减轻IR介导的损伤、巨噬细胞炎症极化和T细胞同种异体反应 来自人类原位肝移植受体，以及在IRI啮齿动物模型中的应用。空间免疫图谱的原位检测 在对照器官和耐受器官中供体和受体髓系细胞的比较将探索IRI介导的免疫细胞和 实质改变有助于移植物的调节状态与炎症状态。目标3将决定 DAMP/PRR内型对同种异体免疫生成和移植物预后的影响。我们将评估 DAMP/PRR内型指导同种异体反应性T细胞和供体特异性T细胞的产生和广度 抗体。数据将与临床元数据、血液和移植物免疫表型、IRI和移植相结合 结果确定DAMP/PRR内型对IRI的易感性和更糟糕的结果。

PROJECT 3 - SUMMARY/ABSTRACT Ischemia and reperfusion injury (IRI), the inevitable consequence of the transplant process, is a key limitation to human liver transplantation. The cellular damage incurred by IRI can lead to primary non-function necessitating re-transplantation. Liver IRI also predisposes the recipient to both acute and chronic rejection and graft loss, as well as, decreasing the pool of transplantable organs. Key observations in murine models indicate that liver IRI is mediated by both the innate and adaptive immune systems. Little is known whether similar mechanisms are at play in human liver transplantation. Our central hypothesis is that identifying the DAMPs and their associated PRRs driving myeloid cell plasticity during human OLT-IRI will permit us to develop therapeutic interventions to improve OLT outcomes. Aim 1, we will determine the TLR9 and TLR7/NOD2 ligands mediating differential polarization of inflammatory vs. regulatory macrophages and crosstalk with T cells. We will characterize the cell- free DNA/TLR9 ligands mitochondrial DNA, neutrophil extracellular traps, and HMGB1/RAGE in pre/post reperfusion blood to establish their contributions to human OLT-IRI, ability to polarize macrophages and develop alloreactive T cells. We will also determine the tolerogenic effect of TLR7 and NOD2 ligands for their regulatory potential to mitigate TLR4 and/or TLR9 polarization and suppression of alloimmunity. Characterization of longitudinal changes in myeloid and T cell phenotypes of recipient blood and donor allograft biopsies obtained pre- and post-reperfusion will identify new targetable interactions along the endotype-specific pathways TLR4/TLR9 and TLR7/NOD2 in situ. Aim 2 will determine the therapeutic potential of PRR preconditioning to mitigate myeloid activation and OLT-IRI. We will assess the therapeutic potential of TLR4/9 antagonists to mitigate IR mediated-injury, macrophage inflammatory polarization and T cell alloreactivity in vitro using blood from human OLT recipients, and in vivo in rodent models of IRI. In situ assessment of the spatial immune profile of donor vs. recipient myeloid cells in control vs. tolerized organs will explore the IRI-mediated immune cell and parenchymal changes contributing to a regulatory vs inflammatory state in the graft. Aim 3 will determine the impact of DAMP/PRR endotypes on generation of alloimmunity and graft outcome. We will assess the DAMP/PRR endotypes that direct the generation and breadth of alloreactive T cells and donor specific antibodies. Data will be integrated with clinical metadata, blood and graft immunophenotypes, IRI and transplant outcomes to determine DAMP/PRR endotypes responsible for susceptibility to IRI and worse outcomes.