Mechanisms of Cellular and Humoral Immune Evasion and Subsequent Polyomavirus Encephalitis

细胞和体液免疫逃避及随后的多瘤病毒脑炎的机制

• 批准号: 9760815
• 负责人: Heather Marie Ren
• 金额: $ 2.54万
• 依托单位: PENNSYLVANIA STATE UNIV HERSHEY MED CTR
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2020-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9760815
• 关键词: AIDS/HIV problem; Acquired Immunodeficiency Syndrome; Adaptive Immune System; Allografting; Amino Acids; Animal Model; Antibodies; Antibody Affinity; Antibody Repertoire; Antibody Response; Antibody Specificity; Antiviral Agents; Autoimmune Diseases; Autoimmune Process; B-Lymphocytes; Biological Assay; Blood; Brain; Brain Diseases; CD4 Positive T Lymphocytes; CD8-Positive T-Lymphocytes; CD8B1 gene; Capsid Proteins; Cells; Central Nervous System Diseases; Central Nervous System Infections; Chronic; Complication; Data; Defect; Development; Disease; Encephalitis; Enzyme-Linked Immunosorbent Assay; Epitopes; Genomic DNA; Goals; HIV; Haplotypes; Hematologic Neoplasms; Homeostasis; Host Defense; Humoral Immunities; Immune; Immune Evasion; Immune response; Immunocompromised Host; Immunoglobulin G; Immunohistochemistry; Immunologic Monitoring; Immunologics; Immunosuppression; Impairment; Incidence; Individual; Infection; Inflammatory; Integrin alpha4; Interleukin-10; Interleukins; JC Virus; Label; Laboratories; Lesion; Life; Link; Maintenance; Mediating; Memory; Messenger RNA; Modeling; Monoclonal Antibodies; Multiple Sclerosis; Mus; Mutant Strains Mice; Mutation; Neuraxis; Neuroglia; Pathogenesis; Patients; Plasma Cells; Polyomavirus; Polyomavirus Infections; Prevention; Preventive therapy; Preventive treatment; Production; Progressive Multifocal Leukoencephalopathy; Proteins; Reaction; Receptor Cell; Receptor Signaling; Residencies; Role; Serum; Signal Transduction; Source; Specificity; Structure of germinal center of lymph node; Systemic Lupus Erythematosus; T cell response; T-Lymphocyte; Testing; Time; Tissues; Transplantation; Tropism; Tumor-infiltrating immune cells; Variant; Viral; Virus; Virus Diseases; base; central nervous system demyelinating disorder; chemotherapy; cytokine; immunomodulatory therapies; immunosuppressed; improved; interleukin-21; interleukin-21 receptor; leukemia; mouse model; mouse polyomavirus; multiple sclerosis patient; mutant; natalizumab; neurotropic; neurotropic virus; neutralizing antibody; prevent; receptor; residence; response; transcriptome; transcriptome sequencing

ABSTRACT Progressive Multifocal Leukoencephalopathy (PML), a life-threatening demyelinating brain disease caused by JC polyomavirus (JCV), is a significant complication for patients with HIV/AIDS, hematologic malignancies, rheumatologic diseases, and those receiving long-term immunomodulating therapies. The immunomodulating therapy mostly closely associated with PML is natalizumab, an α4 integrin antibody (Ab) commonly used to treat multiple sclerosis (MS). Lack of a tractable animal model for PML is a widely recognized hurdle to defining the mechanisms of immunological control of JCV CNS infection. Using mouse polyomavirus (MuPyV), our laboratory developed a robust model of polyomavirus-associated demyelinating leukoencephalitis, with viral infection and T cell infiltration. This proposal seeks to use the MuPyV-CNS infection model to mechanistically understand the cellular and humoral immune mechanisms in place to control JCV CNS infection and how immunosuppression predisposes patients to JCV CNS infection. Increasing evidence supports the importance of CD4+ T cells in controlling JCV and thereby preventing PML. Recent studies in our laboratory show that CD4+ T cells are essential for differentiation and maintenance of MuPyV-specific tissue-resident memory CD8+ T cells (TRMs) in the brain. My preliminary data strongly supports the likelihood that IL-21 is a major component of the help provided by CD4+ T cells. I have further found that the serum from IL-21 receptor (IL21R)-deficient mice has a reduced ability to neutralize MuPyV carrying an amino acid mutation in its VP1 capsid protein that corresponds to a frequent VP1 mutation in PML-JCV. In Specific Aim 1, I hypothesize that IL-21 is required for brain-infiltrating CD8+ T cells to differentiate into TRMs. To test this hypothesis, I will define a time course for IL-21 production in the MuPyV-infected brain, its cellular sources, and when its receptor is expressed by MuPyV-specific CD8+ T cells. Using donor MuPyV-specific CD8+ T cells lacking IL21R, I will determine if signaling through the IL21R is intrinsically required by CD8+ T cells for their differentiation into TRMs. I will also apply RNA-seq to determine if the transcriptomes of IL21R-/- CD8+ T cells in the brain are similar to CD8+ T cells in CD4+ T cell-deficient mice. In Specific Aim 2, I hypothesize that IL21R signaling diversifies the VP1 Ab repertoire in a B cell-intrinsic manner to facilitate recognition of a MuPyV carrying a PML-synonymous VP1- mutation. To test this hypothesis, I will use MuPyV Ab neutralization assays, ELISAs, and germinal center immunohistochemistry to define the time course for developing a hole in the VP1 Ab specificity repertoire under T-independent (TCRα-/-) and IL-21-deficient (IL21R-/-) conditions. I also will determine plasma cell specificity against the PML-synonymous VP1 MuPyV mutant using fluorescently labeled MuPyVs in these aforementioned conditions. Finally, I will distinguish whether the mechanistic basis for the diminished VP1 neutralizing Ab repertoire is due to an intrinsic defect in IL21R signaling in B and/or T cells.

抽象的 进行性多灶性白质脑病 (PML)，一种由以下疾病引起的危及生命的脱髓鞘性脑病 JC 多瘤病毒 (JCV) 是 HIV/AIDS、血液恶性肿瘤、 风湿病以及接受长期免疫调节治疗的患者。 与 PML 密切相关的治疗方法是那他珠单抗，一种 α4 整合素抗体 (Ab)，常用于治疗 治疗多发性硬化症 (MS) 缺乏易处理的 PML 动物模型是定义多发性硬化症的一个广泛公认的障碍。 使用小鼠多瘤病毒 (MuPyV)，我们的 JCV CNS 感染的免疫控制机制。 实验室开发了多瘤病毒相关脱髓鞘性白质脑炎的稳健模型，其中病毒 该提案旨在使用 MuPyV-CNS 感染模型来机械地进行感染和 T 细胞浸润。 了解控制 JCV CNS 感染的细胞和体液免疫机制以及如何控制 JCV CNS 感染 越来越多的证据支持免疫抑制的重要性。 我们实验室最近的研究表明，CD4+ T 细胞可以控制 JCV，从而预防 PML。 CD4+ T 细胞对于 MuPyV 特异性组织驻留记忆 CD8+ 的分化和维持至关重要 我的初步数据强烈支持 IL-21 是主要成分的可能性。 在 CD4+ T 细胞提供的帮助下，我进一步发现 IL-21 受体 (IL21R) 缺陷的血清。 小鼠中和 MuPyV 的能力降低，该 MuPyV 的 VP1 衣壳蛋白中携带氨基酸突变，导致 对应于 PML-JCV 中频繁出现的 VP1 突变。在特定目标 1 中，我纠结是否需要 IL-21。 为了验证这一假设，我将定义一个时间过程。 MuPyV 感染大脑中 IL-21 的产生、其细胞来源以及其受体何时表达 使用缺乏 IL21R 的 MuPyV 特异性 CD8+ T 细胞，我将确定是否 CD8+ T 细胞分化为 TRM 本质上需要通过 IL21R 发出信号。 应用 RNA-seq 确定大脑中 IL21R-/- CD8+ T 细胞的转录组是否与 CD8+ T 相似 在特定目标 2 中，我发现 IL21R 信号传导使 VP1 Ab 多样化。 以 B 细胞固有的方式来促进识别携带 PML 同义 VP1- 的 MuPyV 为了检验这个假设，我将使用 MuPyV Ab 中和测定、ELISA、生发中心。 免疫组织化学确定 VP1 Ab 特异性库中出现空洞的时间过程 在 T 独立 (TCRα-/-) 和 IL-21 缺乏 (IL21R-/-) 条件下，我还将确定浆细胞。 使用荧光标记的 MuPyV 在这些中针对 PML 同义 VP1 MuPyV 突变体的特异性 最后，我将区分VP1减少的机制基础是否 中和抗体库是由于 B 和/或 T 细胞中 IL21R 信号传导的内在缺陷所致。