CMV PATHOGENESIS AND CELLULAR TROPISM

CMV 发病机制和细胞趋向性

• 批准号: 8358007
• 负责人: Susan V. Westmoreland
• 金额: $ 6.84万
• 依托单位: HARVARD MEDICAL SCHOOL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-05-01 至 2012-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8358007
• 关键词: Achievement; Acquired Immunodeficiency Syndrome; Animal Experimentation; Animal Model; Animals; Bladder; Bodily secretions; Cell Adhesion; Cellular Tropism; Chemotactic Factors; Chemotaxis; Clinical; Complex; Cytomegalovirus; Disease; Endothelial Cells; Epithelial Cells; Exhibits; Fetus; Funding; Gene Family; Genes; Grant; Herpesviridae; Homologous Gene; Human; Human Milk; IL8 gene; Immunocompromised Host; In Vitro; Infection; Leukocytes; Macaca mulatta; Mammary gland; Mediating; National Center for Research Resources; New England; Organ; Pan Genus; Pathogenesis; Patients; Play; Population; Primates; Principal Investigator; Relative (related person); Reporting; Research; Research Infrastructure; Resources; Role; Saliva; Salivary Glands; Seizures; Severities; Source; Species Specificity; Transplantation; United States National Institutes of Health; Urine; Vaccines; Viral; Virus; Virus Shedding; base; cost; disease transmission; improved; in vivo; in vivo Model; monocyte; neutrophil; prevent; repaired

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Human cytomegalovirus (HCMV) is a ubiquitous ¿-herpesvirus infecting 50-90% of the population. HCMV is transmitted through bodily secretions including saliva, urine, and breast milk. Once inside the body the virus infects epithelial and endothelial cells and eventually infects leukocytes, primarily monocytes and neutrophils, which then disseminate the virus systemically to multiple organs including salivary glands, urinary bladder, and mammary gland. Although asymptomatic in most cases, HCMV can cause fatal disease in immunocompromised patients after transplantation, in AIDS patients, and in the fetus. Although a need for a CMV vaccine has been emphasized, no successful vaccine has been developed to date. This is partially limited by the species specificity of cytomegaloviruses and the lack of a representative animal model that precisely mimics HCMV. A crucial step in all clinical HCMV cases is viral replication in endothelial cells and the associated viral dissemination mediated by leukocytes. HCMV is transmitted bidirectionally between endothelial cells and leukocytes through viral seizure of normal leukocyte-endothelial cell adhesion mechanisms, formation of microfusion, and permitting virus passage through direct intercellular transport. Preventing the dissemination of the virus in a host may reduce the severity of CMV disease and transmission of the virus to others. In vitro studies indicate that HCMV UL131-128 genes are essential for viral replication in endothelial cells and transfer to leukocytes. In addition, virally encoded chemotactic factors IL-8 and GRO¿ within UL146-147 strongly enhance virus passage to neutrophils in vitro. In vivo studies to date are limited. Beta-herpesviruses are highly species-specific. The closest relative to HCMV is chimpanzee CMV (CCMV), but this is not a practical animal model. Rhesus macaques are a more widely used experimental animal species and rhesus CMV (RhCMV) contains most of the HCMV gene families. Multiple reports have recently characterized genes in RhCMV that represent the HCMV UL131-128 and UL146-147 gene homologues. In a recent report, Lilja et. al. repaired the deleted UL131-UL128 locus of RhCMV strain 68-1 in a BAC-derived infectious virus and observed that the repaired derivative replicates much more efficiently than parental 68-1 virus in rhesus epithelial cells and in cultured human epithelial cells and endothelial cells. These recent achievements will facilitate examination of CMV cellular tropism and dissemination improving our understanding of the pathogenesis of CMV in both rhesus monkeys and humans. In this study we will examine the effects of UL131-128 and UL146-147 genes on the cellular tropism and dissemination of RhCMV. We will compare cellular tropism from in vivo infections in rhesus macaques with naturally occurring wild-type RhCMV, RhCMV strain 68-1 (lacking the UL131-128 gene region and having inverted UL146-147 gene region), and RhCMV strain 180.92 (lacking the UL146-147 gene region). We hypothesize that animals infected with strain 68-1, which lacks UL128 complex, will not exhibit endothelial infection. We further expect that lack of intact UL128 complex in our in vivo model will hamper viral dissemination to the salivary glands and urinary bladder, and consequently reduce viral shedding in saliva and urine. In addition, we hypothesize that animals infected with strain180.92, which lacks UL146-147, will not exhibit neutrophilic chemotaxis. Since we believe that neutrophils also play a role in systemic viral dissemination, we expect that animals infected with CMV strains lacking functional UL146-147 will exhibit reduced viral dissemination compared to the wild-type RhCMV.

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 人巨细胞病毒(HCMV)是一种普遍存在的疱疹病毒，感染人群的比例为50%-90%。人巨细胞病毒通过包括唾液、尿液和母乳在内的身体分泌物传播。一旦进入体内，病毒就会感染上皮细胞和内皮细胞，最终感染白细胞，主要是单核细胞和中性粒细胞，然后将病毒系统性地传播到包括唾液腺、膀胱和乳腺在内的多个器官。尽管在大多数情况下没有症状，但巨细胞病毒可以在移植后免疫功能低下的患者、艾滋病患者和胎儿中导致致命疾病。尽管强调了CMV疫苗的必要性，但到目前为止还没有成功的疫苗被开发出来。这在一定程度上受到巨细胞病毒的物种特异性和缺乏精确模拟巨细胞病毒的代表性动物模型的限制。 在所有临床巨细胞病毒病例中，关键的一步是病毒在内皮细胞中的复制和由白细胞介导的相关病毒传播。人巨细胞病毒通过病毒侵袭正常的白细胞-内皮细胞黏附机制，形成微融合，并允许病毒通过细胞间的直接转运，在内皮细胞和白细胞之间双向传播。防止病毒在宿主中传播可能会减轻CMV病的严重程度，并将病毒传播给其他人。体外研究表明，HCMV UL131-128基因对病毒在内皮细胞中的复制和向白细胞的转移是必不可少的。此外，UL146-147中的病毒编码的趋化因子IL-8和Gro？在体外强烈促进病毒对中性粒细胞的传播。到目前为止，体内研究还很有限。 贝塔疱疹病毒具有高度的物种特异性。与巨细胞病毒关系最近的是黑猩猩巨细胞病毒(CCMV)，但这并不是一个实用的动物模型。恒河猴是应用较广泛的实验动物物种，而恒河猴巨细胞病毒(RhCMV)包含了大部分的巨细胞病毒基因家族。最近，许多报道描述了代表巨细胞病毒UL131-128和UL146-147基因同源物的RhCMV基因。在最近的一份报告中，Lilja et.艾尔在BAC来源的感染性病毒中修复了RhCMV 68-1株UL131-UL128缺失的位点，观察到修复后的衍生物在恒河猴上皮细胞以及培养的人上皮细胞和内皮细胞中的复制效率比亲本68-1病毒高得多。这些最新的研究成果将有助于研究巨细胞病毒的细胞趋向性和传播，提高我们对巨细胞病毒在恒河猴和人类体内的致病机制的认识。 在这项研究中，我们将研究UL131-128和UL146-147基因对RhCMV细胞趋向性和传播的影响。我们将比较恒河猴体内感染的细胞嗜性与自然产生的野生型巨细胞病毒、68-1株(缺少UL131-128基因区，具有倒置的UL146-147基因区)和180.92株(缺少UL146-147基因区)的细胞嗜性。我们推测，感染缺乏UL128复合体的68-1菌株的动物不会表现出内皮感染。我们进一步预计，在我们的体内模型中，缺乏完整的UL128复合体将阻碍病毒传播到唾液腺和膀胱，从而减少病毒在唾液和尿液中的脱落。此外，我们假设感染缺乏UL146-147的180.92菌株的动物不会表现出中性粒细胞趋化。由于我们认为中性粒细胞也在系统性病毒传播中发挥作用，我们预计，与野生型RhCMV相比，感染缺乏功能UL146-147的CMV毒株的动物将显示出较少的病毒传播。