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Deciphering Early Stages of Polyomavirus CNS Pathogenesis and Immunity

破译多瘤病毒中枢神经系统发病机制和免疫的早期阶段

基本信息

批准号：
10785321
负责人：
Aron Eliot Lukacher
金额：
$ 8.68万
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：
2022
资助国家：
美国
起止时间：
2022-05-01 至 2030-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10785321
关键词：
Acquired Immunodeficiency Syndrome Address Affinity Animal Model Autoimmune Biological Products Brain Brain Diseases CD4 Positive T Lymphocytes CD8-Positive T-Lymphocytes CD8B1 gene Capsid Proteins Central Nervous System Diseases Central Nervous System Infections Cerebrum Complication Cryoelectron Microscopy Custom Demyelinations Development Disease Ependyma Epitopes Event Family Foundations Hematologic Neoplasms Heterogeneity Human Immune Immunity Immunologics Immunotherapeutic agent Incidence Individual Infection Inflammatory Invaded JC Virus Lesion Life Link Maintenance Maps Memory Modeling Mus Mutation Natural Immunity Pathogenesis Patients Polyomavirus Progressive Multifocal Leukoencephalopathy Reaction Resolution STAT1 gene Staging T cell response T-Lymphocyte Therapeutic Three-Dimensional Imaging Tropism Tysabri Variant Ventricular Virus Visualization brain parenchyma chemotherapeutic agent chronic infection drug withdrawal human pathogen image reconstruction immune modulating agents in vivo in vivo evaluation interleukin-21 mortality mouse polyomavirus multiple sclerosis patient natalizumab neuropathology neutralizing antibody next generation sequencing pathogen preservation tissue culture

项目摘要

ABSTRACT JC polyomavirus (JCPyV), a ubiquitous human pathogen, causes several devastating brain diseases in immune compromised individuals. The most notable of these JCPyV-associated CNS diseases is the frequently fatal demyelinating brain disease progressive multifocal leukoencephalopathy (PML). PML, an AIDS-defining lesion in the pre-cART epoch, has emerged as a life-threatening complication in patients receiving immunomodulatory agents for autoimmune and inflammatory disorders and treatment for certain hematological malignancies. Among the rapidly expanding list of PML-associated biologics, natalizumab (Tysabri®) has the highest incidence and is an ominous sequela for multiple sclerosis (MS) patients who otherwise benefit from dramatic reductions in relapses using this immunomodulatory agent. Drug withdrawal, the only therapeutic option for PML, is often complicated by a high-mortality cerebral inflammatory reaction. No anti-JCPyV agents are available. Polyomaviruses are species-specific. Lack of a tractable animal model of polyomavirus-induced CNS disease is an acknowledged bottleneck to elucidating PML pathogenesis, the immunological mechanisms that control JCPyV, in vivo evaluation of agents that inhibit polyomavirus replication in tissue culture, and uncovering early events that presage irreversible JCPyV-associated neuropathology. Using mouse polyomavirus (MuPyV), we developed a natural virus-host model of polyomavirus-associated CNS disease. In this R35 application, we plan to leverage our three recent key findings: (1) Mapping JCPyV-PML VP1 capsid protein mutations to MuPyV’s VP1 confers escape from virus- neutralizing antibodies (nAb) while preserving CNS tropism; (2) IL-21 produced by high-affinity anti-MuPyV CD4 T cells in the brain is required for formation and maintenance of MuPyV-specific brain resident-memory CD8 T cells (bTRM); and (3) STAT1-dependent innate immunity limits infection of the ventricular ependyma, a critical barrier to infection of the brain parenchyma. These findings lay the foundation for three key questions to be addressed here: (1) Is the ependyma the staging ground for polyomavirus invasion of the brain parenchyma?; (2) Does the integrity of the CD8 bTRM response to persistent infection depend on subset heterogeneity?; and (3) Does T cell deficiency open the door for outgrowth of nAb-escape virus variants? The proposed studies will make use of cutting edge advances in next-generation sequencing to uncover rare VP1 mutations in vivo, custom cryo EM image reconstruction approaches to define endogenous VP1 nAb epitopes and nAb escape mechanisms, and high-resolution 3D imaging of intact mouse brains to visualize virus CNS entry and spread. Findings from these studies will answer fundamental questions about innate and adaptive immune control of polyomavirus CNS infection and conditions underlying dissemination of virus from the periphery into the brain before development of irreversible neuropathology.

抽象的 JC 多瘤病毒 (JCPyV) 是一种普遍存在的人类病原体，可导致多种毁灭性脑部疾病免疫功能低下的个体。这些 JCPyV 相关 CNS 疾病中最值得注意的是经常致命的脱髓鞘性脑病进行性多灶性白质脑病（PML）。 PML，一个 cART 之前时代的艾滋病定义病变已成为危及患者生命的并发症接受免疫调节剂治疗自身免疫性和炎症性疾病以及某些疾病的治疗血液系统恶性肿瘤。那他珠单抗是快速扩大的 PML 相关生物制剂之一 (Tysabri®) 的发病率最高，对于多发性硬化症 (MS) 患者来说是一种不祥的后遗症否则，使用这种免疫调节剂可大大减少复发，从而受益。药物戒断， PML 的唯一治疗选择，通常会并发高死亡率的脑炎症反应。不可以使用抗 JCPyV 药物。多瘤病毒具有物种特异性。缺乏易驯化的动物模型多瘤病毒引起的中枢神经系统疾病是阐明 PML 发病机制的公认瓶颈，控制 JCPyV 的免疫机制，抑制多瘤病毒的药物的体内评估组织培养中的复制，并揭示预示不可逆 JCPyV 相关的早期事件神经病理学。使用小鼠多瘤病毒（MuPyV），我们开发了一种天然病毒宿主模型多瘤病毒相关的中枢神经系统疾病。在此 R35 应用程序中，我们计划利用我们最近的三个关键研究结果：（1）将 JCPyV-PML VP1 衣壳蛋白突变映射到 MuPyV 的 VP1 可以逃避病毒 - 中和抗体 (nAb)，同时保留 CNS 趋向性； (2)高亲和力抗MuPyV产生的IL-21 MuPyV 特异性大脑常驻记忆的形成和维持需要大脑中的 CD4 T 细胞 CD8 T 细胞（bTRM）； (3) STAT1 依赖性先天免疫限制室管膜的感染，脑实质感染的关键屏障。这些发现为解决三个关键问题奠定了基础这里要讨论的是：（1）室管膜是多瘤病毒侵入大脑的舞台吗？薄壁组织？ (2) CD8 bTRM 对持续感染反应的完整性是否取决于子集异质性？ (3) T 细胞缺陷是否为 nAb 逃逸病毒变体的生长打开了大门？这拟议的研究将利用下一代测序的尖端技术来发现罕见的 VP1 体内突变，定制冷冻电镜图像重建方法来定义内源性 VP1 nAb 表位和 nAb 逃逸机制，以及完整小鼠大脑的高分辨率 3D 成像以可视化病毒中枢神经系统进入和传播。这些研究的结果将回答有关先天和适应性的基本问题多瘤病毒中枢神经系统感染的免疫控制和病毒传播的条件在不可逆的神经病理学发展之前，外周细胞进入大脑。