A Mouse Model to Define Immunovirologic Determinants of Polyomavirus CNS Disease

定义多瘤病毒中枢神经系统疾病免疫病毒学决定因素的小鼠模型

基本信息

批准号：
8853962
负责人：
Aron Eliot Lukacher
金额：
$ 33.47万
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：
2014-06-01 至 2019-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8853962
关键词：
A Mouse AIDS/HIV problem Acute Address Adhesions Amino Acid Substitution Animal Model Antibodies Antibody Response Antiviral Agents Autoimmune Process BK Virus Binding Blood Blood - brain barrier anatomy Bone Marrow Brain Brain Diseases CD4 Positive T Lymphocytes CD8B1 gene Capsid Capsid Proteins Cells Central Nervous System Diseases Complex Complication Cutaneous Demyelinating Diseases Demyelinating Encephalopathy Depressed mood Disease Elements Environment Extravasation Family Flow Cytometry Functional disorder Genome Genomic DNA Genotype Goals Health Hematologic Neoplasms Heterogeneity High Prevalence Human Humoral Immunities Hybrids Immune Immunologic Monitoring Immunologics Immunosuppression Immunosuppressive Agents Individual Infection Inflammatory Integrin alpha4beta1 Integrins JC Virus Kidney Diseases Libraries Life Lung MHC Class I Genes Maintenance Mediating Memory Modeling Monitor Monoclonal Antibodies Multiple Sclerosis Mus Mutagenesis Mutation Neuroglia Neurotropism Nonstructural Protein Organ Pathogenesis Patients Play Polyomavirus Polyomavirus Infections Polysaccharides Progressive Multifocal Leukoencephalopathy Receptor Cell Recording of previous events Regimen Relapse Relapsing-Remitting Multiple Sclerosis Replication Origin Risk Risk Factors Role Sialic Acids Skin Tissue Specificity T memory cell T-Lymphocyte Testing Therapeutic immunosuppression Tissues Transgenic Mice Transplant Recipients Tropism Tysabri Urinary tract Variant Viral Viral Tumor Antigens Viral load measurement Virulence Virus base brain tissue cell motility central nervous system injury exhaustion humanized monoclonal antibodies immune function immunosuppressed in vivo kidney allograft mouse model mouse polyomavirus mutant natalizumab neurotropic neurovirulence neutralizing antibody next generation sequencing novel pathogen pre-clinical prevent residence seropositive white matter

项目摘要

DESCRIPTION (provided by applicant): Progressive Multifocal Leukoencephalopathy (PML), a demyelinating encephalopathy caused by the human JC polyomavirus, is a life-threatening complication of natalizumab therapy for relapsing multiple sclerosis. Seropositivity for JCV, prior immunosuppression, and > 24 month of natalizumab treatment are the only identified factors known to increase risk for PML, but their utility is limited because of the high prevalence of JCV infection and the heterogeneity of immunosuppressive regimens patients receive before starting natalizumab. No anti-JCV agents are available. Elucidation of the pathogenesis of PML and immunosurveillance mechanisms that keep JCV replication in check are required to adequately assess risk for PML in MS individuals receiving natalizumab. Polyomaviruses are highly species specific, with humans being the only host reservoir for JCV. A tractable animal model is urgently needed to understand the immunologic and virologic determinants of JCV-induced PML, and to provide a preclinical platform to assess the in vivo efficacy of novel anti-JCV compounds. Using mouse polyomavirus (MPyV), we have developed a mouse model of polyomavirus-induced CNS disease. We propose applying this MPyV-CNS infection model to address two Aims based on the following hypotheses: (1) by blocking T cell extravasation across the blood-brain barrier into the CNS parenchyma, natalizumab prevents maintenance of brain-resident virus-specific CD8 T cells required for antiviral immunosurveillance; and (2) because JCV in PML patients harbor novel mutations in their capsid protein, the dominant target for humoral-mediated immune defense, virus-neutralizing antibodies select viral variants that acquire neurotropism. For Aim 1, we have constructed MHC class I and class II tetramers to visualize MPyV-specific CD8 and CD4 T cells by flow cytometry, and have developed an MPyV- specific TCR transgenic mouse to monitor the fate of anti-MPyV CD8 T cells in the CNS. For Aim 2, we will create a library of capsid mutant MPyVs by PCR-based random mutagenesis, and by combining iterative virus passaging in vivo with next-generation sequencing, determine whether neutralizing MPyV antibodies select mutations that confer neurovirulence. We will also attempt to create a hybrid virus expressing the capsid proteins of JCV (to confer JCV host cell specificity) and having the noncoding control elements, origin of replication, and nonstructural proteins of MPyV (to enable replication in the mouse). This novel hybrid virus will allow us to determine the functional significance of the capsid mutations in JCV-PML variant viruses.

描述（由申请人提供）：进行性多灶性白质脑病（PML）是一种由人类 JC 多瘤病毒引起的脱髓鞘性脑病，是那他珠单抗治疗复发性多发性硬化症的危及生命的并发症。 JCV 血清阳性、既往免疫抑制和那他珠单抗治疗超过 24 个月是唯一已知会增加 PML 风险的因素，但由于 JCV 感染的高患病率以及患者在开始那他珠单抗之前接受的免疫抑制方案的异质性，其效用有限。没有可用的抗 JCV 药物。需要阐明 PML 的发病机制和控制 JCV 复制的免疫监视机制，以充分评估接受那他珠单抗的 MS 个体发生 PML 的风险。多瘤病毒具有高度物种特异性，人类是 JCV 的唯一宿主。迫切需要一个易于处理的动物模型来了解 JCV 诱导的 PML 的免疫学和病毒学决定因素，并提供一个临床前平台来评估新型抗 JCV 化合物的体内功效。使用小鼠多瘤病毒（MPyV），我们开发了多瘤病毒诱导的中枢神经系统疾病的小鼠模型。我们建议应用这种 MPyV-CNS 感染模型来解决基于以下假设的两个目标：（1）通过阻止 T 细胞跨血脑屏障外渗到 CNS 实质，那他珠单抗可防止脑驻留病毒特异性 CD8 T 的维持抗病毒免疫监视所需的细胞； (2) 由于 PML 患者的 JCV 在其衣壳蛋白（体液介导的免疫防御的主要靶标）中存在新的突变，因此病毒中和抗体会选择获得向神经性的病毒变体。对于目标 1，我们构建了 MHC I 类和 II 类四聚体，通过流式细胞术可视化 MPyV 特异性 CD8 和 CD4 T 细胞，并开发了 MPyV 特异性 TCR 转基因小鼠来监测抗 MPyV CD8 T 细胞的命运中枢神经系统。对于目标 2，我们将通过基于 PCR 的随机诱变创建衣壳突变体 MPyV 文库，并通过将体内迭代病毒传代与下一代测序相结合，确定中和 MPyV 抗体是否选择赋予神经毒力的突变。我们还将尝试创建一种表达 JCV 衣壳蛋白（以赋予 JCV 宿主细胞特异性）并具有非编码控制元件、复制起点和 MPyV 非结构蛋白（以实现在小鼠中复制）的杂交病毒。这种新型杂交病毒将使我们能够确定 JCV-PML 变种病毒中衣壳突变的功能意义。