High-dimensional single-cell mapping to define immune signatures of cytomegalovirus-associated rejection in cardiac transplantation

项目摘要 人巨细胞病毒（CMV）是使心脏移植复杂化的最常见的病毒感染， 细胞排斥反应的一个重要风险因素而CMV通过直接的病毒感染对原生器官造成损害， CMV介导的心脏同种异体移植排斥反应是由于“免疫失调”， 其机制尚不清楚。这些信息对移植领域至关重要，因为 细胞排斥反应的治疗，即使在并发CMV病毒血症的情况下，也包括免疫抑制， 可能导致病毒血症控制失效和CMV相关发病率升高的方法，包括 排斥反应恶化和其他机会性感染。细胞排斥反应是由细胞毒性T细胞介导的， 淋巴细胞（CTL），最近的范式转移工作表明，激活的单核吞噬细胞， (MP)细胞还在通过训练的免疫力驱动同种异体移植物排斥中具有关键作用。这些发现 这在CMV介导的移植排斥的背景下是有趣的，因为MP细胞是重要的CMV病毒储库。的 在这个提议中被测试的中心假设是CMV介导的MP系统的失调触发了一种新的免疫反应。 独特的排斥表型，驱动明显增殖和同种异体反应性CTL浸润到心脏 同种异体移植组织该提案的目的是利用多组学策略，包括scRNA-seq和 CITE-seq，以解码CMV病毒血症期间排斥反应中的同种异体移植物组织微环境，重点是 了解MP细胞如何协调同种异体反应性CTL应答（Aim 1），并确定组织MP和 CTL细胞状态反映在血液中（目的2）。为了实现这一点，我们将研究肌内膜组织， 来自马萨诸塞州布里格姆（MGB）的220名心脏移植受者的配对血液。这些研究将 区分CMV介导和CMV非依赖性细胞排斥机制， 针对病毒或非病毒原因定制的诊断工具和排斥治疗策略， 心脏移植中的药物Sen博士将在移植中执行本K 08提案中的工作， 布里格姆妇女医院（BWH）肿瘤传染病组，继续与 马萨诸塞州总医院（MGH）免疫学和炎症疾病中心，细胞回路 布罗德研究所（MIT）和哈佛医学院（HMS）的研究小组。森博士设计了一个职业 发展计划包括课程作业，实践培训，以及单细胞“组学”的专家指导， 生物信息学，同种免疫和耐受生物学，心脏组织微环境，体内宿主- 病原体相互作用和人体研究。K 08奖将为森博士提供培训， 有必要成为一个独立的，R 01资助的研究者，具有宿主-病原体相互作用的专业知识， 移植免疫失调。

PROJECT SUMMARY Human cytomegalovirus (CMV) is the most common viral infection to complicate cardiac transplantation and is an important risk factor for cellular rejection. While CMV causes damage to native organs through direct viral cytopathic effect, CMV-mediated cardiac allograft rejection is attributed to “immune dysregulation,” the mechanisms for which are not well understood. This information is critical to the field of transplantation, as treatment of cellular rejection, even in cases with concurrent CMV viremia, includes immunosuppression, an approach that confers risk of abrogation of viremic control and precipitation of CMV-related morbidity, including worsening rejection and other opportunistic infections. While cellular rejection is mediated by cytotoxic T lymphocytes (CTL), recent paradigm-shifting work has demonstrated that activated mononuclear-phagocytic (MP) cells also have a critical role in driving allograft rejection through trained immunity. These findings are intriguing in the context of CMV-mediated graft rejection as MP cells are an important CMV viral reservoir. The central hypothesis being tested in this proposal is that CMV-mediated dysregulation of the MP system triggers a unique rejection phenotype that drives the infiltration of distinctly proliferative and alloreactive CTL into cardiac allograft tissue. The objective of this proposal is to leverage multi-omics strategies, including scRNA-seq and CITE-seq, to decode the allograft tissue microenvironment in rejection during CMV viremia, with a focus on understanding how MP cells orchestrate alloreactive CTL responses (Aim 1) and determine if tissue MP and CTL cell states are reflected in the blood (Aim 2). To accomplish this, we will study endomyocardial tissue and paired blood from a cohort of 220 heart transplant recipients at MassGeneralBrigham (MGB). These studies will distinguish CMV-mediated and CMV-independent mechanisms of cellular rejection, allowing for the development of diagnostic tools and rejection treatment strategies tailored to viral or non-viral causes, promoting precision medicine in cardiac transplantation. Dr. Sen will perform the work in this K08 proposal in the Transplant and Oncology Infectious Diseases Group at Brigham and Women’s Hospital (BWH), with continued affiliation with the Center for Immunology and Inflammatory diseases at Massachusetts General Hospital (MGH), Cell Circuits Group at the Broad Institute (MIT) and Harvard Medical School (HMS). Dr. Sen has devised a career development plan consisting of coursework, hands-on training, and expert mentorship in single-cell ‘omics,’ bioinformatics, the biology of alloimmunity and tolerance, cardiac tissue microenvironments, in vivo host- pathogen interactions, and human subjects research. The K08 award will provide Dr. Sen with the training necessary to become an independent, R01-funded investigator with expertise in host-pathogen interactions and immune dysregulation in transplantation.