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

项目总结 人巨细胞病毒(CMV)是导致心脏移植并发症的最常见的病毒感染， 这是细胞排斥反应的重要风险因素。而CMV通过直接病毒对自然器官造成损害 细胞病变效应，巨细胞病毒介导的同种异体心脏移植排斥反应归因于“免疫失调，” 其机制还不是很清楚。这一信息对移植领域至关重要，因为 细胞排斥的治疗，即使在并发CMV病毒血症的病例中，也包括免疫抑制，以及 有可能消除病毒控制和减少巨细胞病毒相关发病率的办法，包括 不断恶化的排斥反应和其他机会性感染。而细胞排斥反应是由细胞毒性T细胞介导的 淋巴细胞(CTL)，最近的范式转变工作表明，激活的单核巨噬细胞 (MP)细胞也通过训练免疫在驱动同种异体移植排斥反应中发挥关键作用。这些发现是 耐人寻味的是，在巨细胞病毒介导的移植物排斥反应的背景下，MP细胞是一个重要的CMV病毒库。这个 在这项提议中检验的中心假设是，CMV介导的MP系统的调节失调触发了 独特的排斥表型促使明显增殖性和同种异体反应性CTL渗入心脏 同种异体组织。该提案目标是利用多种组学战略，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移植组织微环境，重点是 了解MP细胞如何协调同种异体反应性CTL反应(目标1)，并确定组织MP和 CTL细胞状态反映在血液中(目标2)。为了实现这一点，我们将研究心内膜心肌组织和 马萨诸塞州总医院200名心脏移植患者的配对血液 移植中心。这些研究将区分CMV介导的和非CMV依赖的细胞内机制 排斥反应，允许开发诊断工具和排斥反应治疗策略，为病毒或 非病毒原因，促进心脏移植的精准医学。森博士将在这里执行这项工作 在MGH免疫和炎症疾病中心(CIID)的指导下的K08提案 安德鲁·卢斯特博士和亚历山德拉·克洛伊·维拉尼博士。CID是一项最先进的多学科研究 该中心专注于免疫介导性炎症性疾病的机制，是 麻省理工学院的免疫学研究。森博士设计了一项职业发展计划，包括课程和 单细胞组学、生物信息学、同种异体免疫和耐受生物学、心脏组织方面的实践培训 微环境、体内宿主-病原体相互作用和人类受试者研究，以及组织了 培训咨询委员会，由约伦·马德森博士担任主席，在这些领域提供专门知识和援助。 K08奖项将为森博士提供必要的智力和技术培训，以成为一名 R01资助的独立研究员，在宿主-病原体相互作用和免疫失调方面具有专业知识 移植。

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 200 heart transplant recipients at the Massachusetts General Hospital (MGH) Transplant Center. 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 Center for Immunology and Inflammatory diseases (CIID) at MGH under the mentorship of Dr. Andrew Luster and Dr. Alexandra-Chloe Villani. The CIID is a state-of-the-art multidisciplinary research center focused on mechanisms of immune-mediated inflammatory diseases and is the foundation for immunology research at MGH. Dr. Sen has devised a career development plan consisting of coursework and hands-on training in single-cell ‘omics,’ bioinformatics, the biology of alloimmunity and tolerance, cardiac tissue microenvironments, in vivo host-pathogen interactions, and human subjects research, as well as organized a Training Advisory Committee, chaired by Dr. Joren Madsen, to provide expertise and assistance in these areas. The K08 award will provide Dr. Sen with the intellectual and technical training necessary to become an independent, R01-funded investigator with expertise in host-pathogen interactions and immune dysregulation in transplantation.