Development of a Mouse Model of Progressive Multifocal Leukoencephalopathy

进行性多灶性白质脑病小鼠模型的建立

基本信息

批准号：
8837920
负责人：
Elizabeth Leigh Frost
金额：
$ 2.92万
依托单位：
PENNSYLVANIA STATE UNIV HERSHEY MED CTR
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-01-01 至 2015-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8837920
关键词：
AIDS/HIV problem Acute Affect Affinity Allografting Amino Acid Substitution Animal Model Antibodies Antiviral Agents Autoimmune Diseases Autoimmune Process BCL6 gene BK Virus Binding Binding Sites Bone Marrow Brain CD4 Positive T Lymphocytes CD8B1 gene Capsid Capsid Proteins Cells Central Nervous System Diseases Central Nervous System Infections Cerebrospinal Fluid Cytolysis Demyelinations Depressed mood Development Disabled Persons Disease Disease Progression Evaluation Flow Cytometry Functional disorder Goals Health Hematologic Neoplasms Hematological Disease Histopathology Human Immune Immune system Immunocompetent Immunofluorescence Microscopy Immunologic Monitoring Immunosuppression Immunosuppressive Agents Incidence Individual Infection Infection Control Inflammatory Integrin alpha4beta1 JC Virus Kidney Kidney Diseases Laboratories Lesion Leucocytic infiltrate Life Lytic Maintenance Maps Mediating Memory Modeling Monoclonal Antibodies Monoclonal Antibody Therapy Multiple Sclerosis Mus Mutation Neuraxis Neurodegenerative Disorders Neuroglia Neurologic Oligodendroglia Organ Pathogenesis Patients Pharmaceutical Preparations Play Point Mutation Polymerase Chain Reaction Polyomavirus Polyomavirus Infections Population Positioning Attribute Predisposition Progressive Multifocal Leukoencephalopathy Relapsing-Remitting Multiple Sclerosis Risk Risk Factors Role Satellite Viruses Severities Sialic Acids Site Species Specificity T cell response T memory cell T-Lymphocyte Testing Tissues Transplantation Tropism Untranslated RNA Urinary tract Urine Viral Viral Load result Virulence Virus Virus-like particle Work adverse outcome base cell type central nervous system demyelinating disorder central nervous system injury handicapping condition humanized monoclonal antibodies immune function immunosuppressed kidney allograft leukemia migration mortality mouse model mouse polyomavirus mutant natalizumab neuropathology neurotropic neurovirulence pathogen prevent receptor binding trafficking treatment duration

项目摘要

DESCRIPTION (provided by applicant): Human JC polyomavirus (JCV) is the causative agent of progressive multifocal leukoencephalopathy (PML), a life-threatening demyelinating disease of the central nervous system (CNS) resulting from infection of oligodendrocytes. JCV infection is prevalent in the human population, where it persists lifelong as an asymptomatic infection in healthy individuals. JCV-induced PML manifests in individuals immunosuppressed by HIV/AIDS, leukemia, allograft transplantation, or, more recently, monoclonal antibody-mediated therapy for autoimmune and inflammatory diseases. Natalizumab, a monoclonal antibody therapy for treatment of multiple sclerosis, carries a risk for PML; incidence of PML in these patients rises with duration of treatment. This therapy is intended to prevent migration of autoimmune T cells to their target tissues, but blockade of trafficking of JCV-specific T cells into the CNS is generally considered its adverse consequence. JCV isolated from PML patients were found to have mutations in the major capsid protein VP1 and the non-coding control region (NCCR), implicating virus-associated risk factors in addition to host immune compromise. Several specific VP1 mutations have been identified, all of which are single amino acid substitutions that map to sialic acid binding sites, which are involved in attachment and entry of virus into host cells. Species-specificity of polyomaviruses has severely impeded development of a tractable JCV-PML animal model, and as a result our understanding of the pathogenesis of PML is limited. For example, it remains to be determined if mutations in VP1 alter virulence, and the role that immunosuppression plays in disease progression. The goal of this project is to develop a model of PML in mice using mouse polyomavirus (MPyV) to investigate how virus capsid mutations, adaptive immune system deficiencies, and treatment with natalizumab contribute to induction of polyomavirus- induced CNS disease. Introduction of a PML-associated substitution into an analogous site in VP1 of MPyV is hypothesized to increase the severity of CNS disease in mice by making MPyV neurotropic, allowing infection and damage of glial cells, including oligodendrocytes. Shifts in tropism will be determined by quantitative polymerase chain reaction (PCR) to assess viral replication efficiency, immunofluorescence microscopy to define infected CNS cells, and histopathologic evaluation of CNS injury. As in human PML, CNS infection is likely exacerbated by immunosuppression. Using therapy similar to natalizumab in an MPyV CNS infection model, flow cytometry-based phenotypic and functional analyses will be used to determine the mechanisms by which immunosuppression contributes to pathogenesis. Successful development of this MPyV infection model would provide the opportunity to explore mechanisms of polyomavirus CNS pathogenesis in a natural host.

描述（由申请人提供）：人JC多瘤病毒（JCV）是进行性多灶性白质脑病（PML）的病原体，PML是一种由少突胶质细胞感染引起的危及生命的中枢神经系统（CNS）脱髓鞘疾病。 JCV 感染在人群中普遍存在，在健康个体中它会作为无症状感染终生持续存在。 JCV 诱导的 PML 表现在因 HIV/AIDS、白血病、同种异体移植或最近的单克隆抗体介导的自身免疫和炎症性疾病治疗而受到免疫抑制的个体中。那他珠单抗是一种治疗多发性硬化症的单克隆抗体疗法，存在发生 PML 的风险；这些患者中 PML 的发生率随着治疗时间的延长而升高。这种疗法的目的是防止自身免疫 T 细胞迁移到其靶组织，但阻碍 JCV 特异性 T 细胞进入 CNS 的运输通常被认为是其不良后果。从 PML 患者中分离出的 JCV 被发现在主要衣壳蛋白 VP1 和非编码控制区 (NCCR) 中存在突变，这表明除了宿主免疫受损之外，还存在与病毒相关的危险因素。已经鉴定出几种特定的 VP1 突变，所有这些突变都是映射到唾液酸结合位点的单个氨基酸取代，这些位点参与病毒附着和进入宿主细胞。多瘤病毒的物种特异性严重阻碍了易处理的 JCV-PML 动物模型的开发，因此我们对 PML 发病机制的了解有限。例如，VP1 突变是否会改变毒力以及免疫抑制在疾病进展中所起的作用仍有待确定。该项目的目标是使用小鼠多瘤病毒 (MPyV) 开发小鼠 PML 模型，以研究病毒衣壳突变、适应性免疫系统缺陷和那他珠单抗治疗如何导致多瘤病毒诱导的中枢神经系统疾病。假设将 PML 相关取代引入 MPyV VP1 的类似位点，可通过使 MPyV 具有嗜神经性，从而增加小鼠中枢神经系统疾病的严重程度，从而允许神经胶质细胞（包括少突胶质细胞）感染和损伤。将通过定量聚合酶链反应（PCR）来确定向性的变化，以评估病毒复制效率，通过免疫荧光显微镜来确定受感染的中枢神经系统细胞，以及中枢神经系统损伤的组织病理学评估。与人类 PML 一样，中枢神经系统感染可能因免疫抑制而加剧。在 MPyV CNS 感染模型中使用类似于那他珠单抗的疗法，基于流式细胞术的表型和功能分析将用于确定免疫抑制导致发病机制的机制。这种 MPyV 感染模型的成功开发将为探索自然宿主中多瘤病毒中枢神经系统发病机制提供机会。