Mechanisms of CMV latency in accelerated vascular disease

描述(申请人提供)：本项目的目标是确定巨细胞病毒(CMV)加速的移植血管硬化症(TVS)所涉及的病毒机制，TVS是与实体器官移植的慢性排斥反应相关的标志性血管疾病。临床研究表明，人巨细胞病毒(HCMV)与移植血管硬化(TVS)、血管成形术后血管再狭窄以及动脉粥样硬化的发生有直接关系。我们已经开发出一种大鼠心脏移植慢性排斥模型，该模型显示了电视在人类身上的所有特征。我们等人的研究表明，在大鼠心脏移植模型中，大鼠巨细胞病毒(RCMV)感染显著加速了TVS的发展和慢性排斥反应。我们观察到，与临床上观察到的情况类似，与未感染对照相比，来自潜伏感染的供体大鼠的同种异体心脏移植经历了慢性排斥反应的加速。有趣的是，我们还观察到更昔洛韦的治疗，它是一种病毒DNA聚合酶抑制剂，可以阻断病毒晚期基因的表达，但并没有阻止RCMV潜伏感染的同种异体移植到血清阴性受体中TVS的加速。这些结果表明，病毒的完全复制不是疾病加速所必需的，病毒的表达仅限于CMV即刻早期(IE)或早期基因产物。在这项研究中，我们将确定同种异体移植物中感染的病毒载量和细胞类型。此外，我们将确定在移植前和移植后潜伏感染的供者的同种异体移植物中表达的病毒基因，然后确定这些基因产物是否有助于加速TV？为了实现这些目标，我们计划了以下具体目标：1.移植前RCMV潜伏感染的细胞类型以及移植前移植物中的病毒表达谱是什么？在移植前，供者心脏中有哪些RCMV潜伏感染的细胞类型？哪些RCMV基因在潜伏感染的供者心脏中表达？2.潜伏感染供者的同种异体移植心脏中RCMV加速的特征是什么？潜伏感染供者的同种异体移植物中TVS的形成动力学是什么？在有更昔洛韦参与的TVS形成过程中，潜伏感染的同种异体移植物中的巨细胞病毒基因表达谱是否发生了变化？3.潜伏感染的同种异体移植物中表达的RCMV基因(S)对TVS的加速是必需的？在潜伏感染的同种异体移植物中表达的RCMV基因的突变是否会改变病毒诱导的疾病加速？在潜伏感染的同种异体移植物中表达的RCMV基因有什么功能？

DESCRIPTION (provided by applicant): The goal of this project is to determine the viral mechanisms involved in cytomegalovirus (CMV)-accelerated transplant vascular sclerosis (TVS), which is the hallmark vascular disease associated with chronic rejection of solid organ grafts. Clinical studies have directly associated human cytomegalovirus (HCMV) with the acceleration of transplant vascular sclerosis (TVS) and vascular restenosis following angioplasty, as well as atherosclerosis. We have developed a rat heart transplant chronic rejection model that exhibits all of the hallmarks of TVS in humans. Studies by our group and others have shown that rat CMV (RCMV) infection significantly accelerates both the development of TVS as well as chronic rejection in the rat heart allograft model. We have observed that similar to what is observed in the clinical setting that heart allografts from latently infected donor rats undergo acceleration of chronic rejection compared to uninfected controls. Interestingly, we have also observed that treatment with ganciclovir, which is a viral DMA polymerase inhibitor that blocks viral late gene expression, did not prevent the acceleration of TVS in RCMV latently infected allografts transplanted into sero-negative recipients. These results indicate that complete viral replication is not required for the acceleration of disease and that virus expression is restricted to CMV immediate early (IE) or early gene products. In this study, we will determine the viral load and cell types infected in the allograft. In addition, we will determine the viral genes that are expressed in the allografts from latently infected donors prior to and following transplantation and then determine whether these gene products contribute to the acceleration of TVS? To achieve these objectives we plan the following specific aims: 1. What are the RCMV latently infected cell types as well as the viral expression profile in the allograft prior to transplantation? A. What are the RCMV latently infected cell types in the donor hearts prior to transplantation? B. Which RCMV genes are expressed in the latently infected donor hearts? 2. What are the characteristics of RCMV acceleration of TVS in allografts from latently infected donors? A. What are the kinetics of TVS formation in allografts from latently infected donors? B. Does the spectrum of RCMV gene expression change in the latently infected allografts during the development of TVS in the presence of ganciclovir? 3. Which RCMV gene(s) expressed in latently infected allografts are required for the acceleration of TVS? A. Does mutation of the RCMV genes expressed in the latently infected allografts alter virus-induced acceleration of disease? B. What is the function of RCMV genes expressed in latently infected allografts?