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.

该子项目是利用资源的众多研究子项目之一 由 NIH/NCRR 资助的中心拨款提供 该子项目的主要支持。 并且子项目的主要研究者可能是由其他来源提供的， 包括其他 NIH 来源的子项目可能列出的总成本。 代表子项目使用的中心基础设施的估计数量， NCRR 赠款不直接向子项目或子项目工作人员提供资金。 人类巨细胞病毒 (HCMV) 是一种普遍存在的病毒- 感染 50-90% 人口的疱疹病毒通过身体分泌物（包括唾液、尿液和母乳）传播。病毒进入体内后会感染上皮细胞和内皮细胞，并最终感染白细胞（主要是单核细胞和中性粒细胞），然后进行传播。尽管大多数情况下无症状，但病毒会全身传播到多个器官，包括唾液腺、膀胱和乳腺。 HCMV 可在移植后的免疫功能低下的患者、艾滋病患者和胎儿中引起致命疾病，尽管人们强调需要 CMV 疫苗，但迄今为止尚未开发出成功的疫苗，这在一定程度上受到巨细胞病毒的物种特异性的限制。且缺乏精确模拟 HCMV 的代表性动物模型。 所有临床 HCMV 病例中的一个关键步骤是病毒在内皮细胞中复制，并且由白细胞介导的相关病毒传播通过病毒捕获正常白细胞-内皮细胞粘附机制、形成微融合并允许在内皮细胞和白细胞之间双向传播。病毒通过直接细胞间运输传播可以减少巨细胞病毒疾病的严重程度以及病毒向其他人的传播。研究表明，HCMV UL131-128 基因对于病毒在内皮细胞中复制和转移至白细胞至关重要。此外，病毒编码的趋化因子 IL-8 和 GRO¿ UL146-147 内的病毒在体外强烈增强病毒进入中性粒细胞，迄今为止的体内研究是有限的。 β-疱疹病毒具有高度的物种特异性，与 HCMV 最接近的是黑猩猩 CMV (CCMV)，但这不是实用的动物模型，恒河猴是更广泛使用的实验动物物种，而恒河猴 CMV (RhCMV) 包含大部分。 HCMV 基因家族最近已鉴定出 RhCMV 中代表 HCMV UL131-128 和 UL146-147 基因的基因。在最近的一份报告中，Lilja 等人修复了 BAC 衍生感染病毒中删除的 RhCMV 病毒株 UL131-UL128 基因座，并观察到修复后的衍生物在恒河猴中的复制效率更高。这些最新成果将有助于检查巨细胞病毒的细胞趋向性和传播，提高我们对巨细胞病毒的理解。 CMV 在恒河猴和人类中的发病机制。 在本研究中，我们将研究 UL131-128 和 UL146-147 基因对 RhCMV 的细胞向性和传播的影响，我们将比较恒河猴体内感染与天然野生型 RhCMV、RhCMV 毒株 68- 的细胞向性。 1 (缺少 UL131-128 基因区域并具有反向 UL146-147 基因区域)，以及RhCMV 菌株 180.92（缺乏 UL146-147 基因区域）我们发现，感染缺乏 UL128 复合物的菌株 68-1 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 复合物将不会表现出内皮感染。阻碍病毒传播到唾液腺和膀胱，从而减少唾液和尿液中的病毒脱落。此外，我们捕获了感染的动物。缺乏 UL146-147 的 180.92 株病毒株不会表现出中性粒细胞趋化性，因为我们相信中性粒细胞也在系统性病毒传播中发挥作用，因此我们预计，与缺乏功能性 UL146-147 的 CMV 病毒株感染的动物相比，感染病毒株的病毒传播会减少。野生型RhCMV。