Characterizing the Role of CMV Latency in Solid Organ Transplant Rejection

表征 CMV 潜伏期在实体器官移植排斥中的作用

• 批准号: 9220714
• 负责人: DANIEL N STREBLOW
• 金额: $ 43.75万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-03-01 至 2021-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9220714
• 关键词: Acceleration; Acute; Address; Allogenic; Allografting; Antigens; Antiviral Response; Binding; Biological Assay; Blood Vessels; Cells; Cercopithecine Herpesvirus 1; Chronic; Clinical; Clinical Research; Complex; Cytomegalovirus; Cytomegalovirus Infections; DNA Polymerase Inhibitor; Defect; Development; Disease; Endothelial Cells; Epithelial Cells; Exhibits; Ganciclovir; Goals; Graft Rejection; Heart; Heart Transplantation; Homologous Gene; Human; Immune; Immune response; Immunologic Deficiency Syndromes; Infection; Infiltration; Inflammatory; Innovative Therapy; Kinetics; Latent Virus; Leukocytes; Life; Ligand Binding; Link; Lymphocyte; Lymphoid; Mediating; Migration Assay; Modeling; Mutation; Names; Operative Surgical Procedures; Organ Donor; Organ Transplantation; Pathogenesis; Patient Care; Phenotype; Play; Point Mutation; Population; Process; Proteins; Rattus; Recruitment Activity; Risk; Rodent; Role; Sclerosis; Solid; Specificity; Structure; T memory cell; T-Cell Activation; T-Lymphocyte; Techniques; Testing; Tissue Donors; Tissues; Transplant Recipients; Transplantation; Transplanted tissue; Vascular Diseases; Viral; Viral Genes; Virus; Virus Latency; Virus Replication; allograft rejection; cell motility; chemokine; cost; graft failure; heart allograft; high risk; immune activation; in vitro Assay; in vivo; macrophage; migration; mutant; organ transplant rejection; prevent; public health relevance; reactivation from latency; scaffold; stem; trafficking; viral DNA

 DESCRIPTION (provided by applicant): The goal of this project is to determine the mechanisms behind Human cytomegalovirus (HCMV) accelerated transplant vascular sclerosis (TVS) and chronic rejection (CR) of solid organ grafts. Approximately 75% of the solid organ donor/recipient population is infected with HCMV making it difficult to avoid the effects of HCMV. During clinical latency, CMV infections cause extraordinary immune responses that are associated with a number of CMV-induced inflammatory diseases including solid organ transplant CR. The mechanisms involved in promoting these deleterious immune responses during latency are still unknown, although they could be mediated by either the anti-viral response to latent virus or by viral genes expressed during persistence that actively promote immune cell infiltration, or both. To determine the mechanisms of immune infiltration and its effects on CR, we have developed a rat heart transplant CR model that exhibits the hallmarks of TVS/CR in humans. Rat CMV (RCMV) infection significantly accelerates the development of TVS/CR in heart allografts from latently infected donors. Surprisingly, ganciclovir treatment of recipients of latently infected donor hearts does not prevent TVS/CR, as its treatment does in acutely infected recipients. We have discovered the accumulation of activated T cells and macrophages in CMV-latently infected hearts prior to transplantation. Passenger leukocytes have been associated with CR and we hypothesize that RCMV-induced alteration of donor tissue immune profiles prior to transplantation mediates the ganciclovir-insensitive rejection of latently infected donor tissues in naïve recipients by providing a scaffold for immune activation. We have found that the RCMV encoded chemokines R129 and R131 (homologues of HCMV UL128 and UL130) are chemotactic towards rat lymphocytes. We hypothesize that these virus-encoded chemokines mediate immune cell infiltration into the heart during latency and predispose the allograft for accelerated CR. However, R129 and R131 are also part of the gH/gL entry complex required for infection of endothelial cells and macrophages. The focus of our proposal is to determine how R129 and R131 mediate immune cell migration and rejection by dissecting the two proposed functions of these molecules using in vitro assays and in vivo pathogenesis and transplantation models. In SA1, we will make point mutations in R129 and R131 that separate chemokine activity from entry mechanisms and test them using migration, ligand binding and entry assays. These mutations will be incorporated into RCMV using BAC recombineering and the viruses will be used in SA2 to characterize the immune cells that infiltrate the heart during latency and promote lymphoid structure formation. We will characterize the changes in T cell profiles in donor hearts during latency as well as their CMV specificity and determine whether chemokine vs. entry complex activity is required for these processes. In SA3, we will determine the role that the viral chemokines play in promoting rejection of latently infected donor hearts by transplanting infected hearts harboring viruses with chemokine vs. entry defects.

 描述（由申请人提供）：本项目的目的是确定人巨细胞病毒（HCMV）加速实体器官移植物移植血管硬化（TVS）和慢性排斥反应（CR）的机制。大约75%的实体器官供体/受体群体感染HCMV，使得难以避免HCMV的影响。在临床潜伏期期间，CMV感染引起与许多CMV诱导的炎性疾病（包括实体器官移植CR）相关的异常免疫应答。在潜伏期期间促进这些有害免疫应答的机制仍然未知，尽管它们可以通过对潜伏病毒的抗病毒应答或通过在持续期间表达的积极促进免疫细胞浸润的病毒基因或两者来介导。为了确定免疫浸润的机制及其对CR的影响，我们开发了一种大鼠心脏移植CR模型，该模型表现出人类TVS/CR的特征。大鼠巨细胞病毒（RCMV）感染显著加速了潜伏感染供体心脏移植物中TVS/CR的发生。令人惊讶的是，更昔洛韦治疗潜在感染的供体心脏的受体并不能预防TVS/CR，因为它的治疗在急性感染的受体。我们已经发现在移植前CMV潜伏感染的心脏中活化的T细胞和巨噬细胞的积累。乘客白细胞与CR相关，我们假设RCMV诱导的供体组织免疫谱的改变在移植前介导了幼稚受体中潜伏感染供体组织的更昔洛韦不敏感排斥反应，通过提供免疫激活的支架。 我们发现RCMV编码的趋化因子R129和R131（HCMV UL 128和UL 130的同源物）对大鼠淋巴细胞具有趋化性。我们假设这些病毒编码的趋化因子介导免疫细胞在潜伏期浸润到心脏，并使同种异体移植物加速CR。然而，R129和R131也是感染内皮细胞和巨噬细胞所需的gH/gL进入复合物的一部分。我们建议的重点是确定R129和R131如何介导免疫细胞迁移和排斥反应，通过解剖这些分子的两个拟议的功能，使用体外测定和体内发病机制和移植模型。在SA 1中，我们将在R129和R131中进行点突变，将趋化因子活性与进入机制分开，并使用迁移，配体结合和进入试验对其进行测试。将使用BAC重组工程将这些突变掺入RCMV中，并且将在SA 2中使用病毒来表征在潜伏期期间浸润心脏并促进淋巴结构形成的免疫细胞。我们将表征供体心脏中T细胞谱在潜伏期期间的变化以及它们的CMV特异性，并确定这些过程是否需要趋化因子与进入复合物活性。在SA 3中，我们将确定病毒趋化因子在通过移植携带趋化因子的病毒与进入缺陷的病毒的受感染心脏来促进潜伏感染的供体心脏的排斥反应中发挥的作用。