Contribution of CMV-specific T cells to chronic kidney rejection

项目摘要 肾移植是终末期肾病(ESKD)患者的救命手段。然而，并发症 包括机会性感染和慢性T细胞和抗体介导的排斥反应减少长期移植物 生死存亡。巨细胞病毒(CMV)血清阳性与术后慢性排斥反应发生率高相关 移植。慢性暴露于巨细胞病毒可诱导巨细胞病毒应答记忆T细胞的免疫衰老 包括丧失增殖能力和分化潜能，同时维持炎症的产生 细胞因子。因此，这些细胞的保护作用变得不那么强，甚至可能促进排斥反应。我的 初步数据表明，对CMV的反应加速了衰老的发展 移植。此外，T细胞介导的炎性巨噬细胞在移植肾中的渗透可以 诱导排斥。巨噬细胞是CMV感染的主要部位。总之，这些观察结果导致了 关于衰老的巨细胞病毒反应性T细胞导致慢性排斥反应的假设将得到验证 通过两个目标。第一个目标的目的是表征巨细胞病毒应答T细胞在感染后的衰老。 移植。对巨细胞病毒有反应的T细胞将在移植后的时间点进行分析 加速衰老。特征将包括通过单细胞RNA进行深入的基因表达谱分析 染色质可及性、端粒长度和增殖的测序和功能分析。的目标是 第二个目标是确定巨细胞病毒反应性T细胞和炎性巨噬细胞是否影响 对慢性排斥反应的敏感性。CMV特异性T细胞和CMV特异性T细胞的数量和分布 将在存档的活检标本中测量进入移植肾的巨噬细胞，以比较患者 诊断为慢性排斥反应的患者为对照组。血液T细胞表型分析 移植活组织检查时的细胞将识别与排斥相关的群体，从长期来看 可能为排斥反应提供一种新的诊断方法。职业生涯规划是让私家侦探成为一名独立调查员 探讨免疫并发症对肾移植的影响。斯坦福大学的研究环境是 非常适合于这些研究，因为可以使用测序、流式细胞仪和显微镜的核心设施。 这些目标提供了与生物信息学家、统计学家、 肾病学家和病理学家，他们是职业规划的关键。具体地说，AIM 1涉及与 Purvesh Khatri博士对测序数据集的复杂数据分析。目标2涉及与 移植肾病学家简·谭和保罗·格林博士以及病理学家Neeraja Kambham博士进行分析和 对活检结果的解释。它还涉及与肾细胞癌研究人员温迪博士的合作 Fantl和统计学家Robert Tibishani博士对活检标本进行了高度多元化的分析。这些目标是 旨在了解巨细胞病毒反应性T细胞在慢性排斥反应中的作用，潜在地 为慢性排斥提供新的治疗方法，并支持申请者向独立的过渡。

Project Summary Kidney transplantation is life-saving for people with end stage kidney disease (ESKD). However, complications including opportunistic infection and chronic T cell- and antibody-mediated rejection reduce long-term graft survival. Seropositivity for cytomegalovirus (CMV) is associated with higher rates of chronic rejection after transplantation. Chronic exposure to CMV induces immunosenescence in CMV-responsive memory T cells, including loss of proliferative capacity and differentiation potential, with maintained production of inflammatory cytokines. In consequence, these cells become less protective, and may even promote rejection. My preliminary data suggest that the development of senescence in response to CMV is accelerated after transplantation. In addition, T cell mediated infiltration of inflammatory macrophages into kidney grafts can induce rejection. Macrophages are a major site of CMV infection. Together, these observations led to the hypothesis that senescent CMV-responsive T cells contribute to chronic rejection that will be tested through two aims. The goal of the first aim is to characterize senescence in CMV-responsive T cells post- transplant. CMV-responsive T cells will be analyzed at post-transplant time points before and after the onset of acceleration of senescence. Characterization will include in-depth gene expression profiling by single cell RNA sequencing and functional assays for chromatin accessibility, telomere length, and proliferation. The goal of the second aim is to determine whether CMV-responsive T cells and inflammatory macrophages influence susceptibility to chronic rejection. Quantity and localization of infiltration of both CMV-specific T cells and macrophages into kidney allografts will be measured in archived biopsy specimens, comparing patients diagnosed with chronic rejection to a control group of patients with chronicity. Phenotypic analysis of blood T cells at the time of transplant biopsy will identify populations correlated with rejection, which in the long-term may provide a new diagnostic of rejection. The career plan is for the PI to become an independent investigator researching the effects of immune complications on kidney transplant. The research environment at Stanford is well suited for these studies, given access to core facilities for sequencing, flow cytometry, and microscopy. The aims provide opportunities to gain expertise in collaboration with bioinformaticians, statisticians, nephrologists, and pathologists, which are key to the career plan. Specifically, Aim 1 involves collaboration with Dr. Purvesh Khatri for complex data analysis of sequencing data sets. Aim 2 involves collaboration with transplant nephrologists Drs Jane Tan and Paul Grimm and pathologist Dr. Neeraja Kambham for analysis and interpretation of biopsy results. It also involves collaboration with renal cell carcinoma researcher Dr. Wendy Fantl and statistician Dr. Robert Tibshirani for highly multiplexed analysis of biopsy specimens. These aims are formulated to gain understanding of the role of CMV-responsive T cells in chronic rejection, potentially to produce new therapies to chronic rejection, and to support the applicant’s transition to independence.