Role of CD8 T cell-mediated Pathology in Globoid Cell Leukodystrophy

CD8 T 细胞介导的病理学在球状细胞脑白质营养不良中的作用

基本信息

批准号：
10634808
负责人：
Stephen J Crocker
金额：
$ 51.91万
依托单位：
UNIVERSITY OF CONNECTICUT SCH OF MED/DNT
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-03-01 至 2028-02-29
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10634808
关键词：
5 year old Address Affect Antibodies Antigen-Presenting Cells Antigens Automobile Driving Behavioral Biochemical Blood Body Weight decreased Brain CD4 Positive T Lymphocytes CD8-Positive T-Lymphocytes CD8B1 gene Cell Therapy Cells Cellular Immunity Central Nervous System Central Nervous System Diseases Cessation of life Child Clinical Cognitive deficits Complex Cytometry Cytotoxic T-Lymphocytes Data Demyelinations Development Disease Effectiveness Flow Cytometry Future Genes Genetic Genetic Diseases Globoid cell leukodystrophy Histologic Human Image Immune Immunity Inflammation Inflammatory Investigational Therapies Knockout Mice Knowledge Lesion Life Expectancy Lipids Live Birth Location Longevity Maps Mediating Meningeal Modeling Molecular Motor Mus Mutation Nature Nerve Degeneration Nerve Tissue Nonsense Codon Oligodendroglia Onset of illness Outcome Outcome Measure Outcome Study Paralysed Pathogenesis Pathogenicity Pathologic Pathology Phenotype Play Population Process Psychosine Reporter Genes Role T cell clonality T-Cell Depletion T-Lymphocyte Technology Testing Therapeutic Therapeutic Intervention Time Tissues Transgenic Animals Transgenic Organisms adaptive immunity brain tissue cell type central nervous system demyelinating disorder cytokine cytotoxic CD8 T cells cytotoxicity defined contribution disability galactosylceramidase gene therapy genetic approach genetic profiling improved insight loss of function loss of function mutation mouse model multidisciplinary neuroinflammation neuropathology novel pharmacologic postnatal preservation prevent response single-cell RNA sequencing spatial relationship success tool transcriptome sequencing transcriptomics white matter

项目摘要

Abstract Globoid cell leukodystrophy (GLD) or Krabbe's disease is a fatal genetic demyelinating disease of the central nervous system affecting 1 in 100,000 live births with no cure or effective long-term treatment. GLD is caused by loss-of-function mutations in the galactosylceramidase (galc) gene, where loss of GALC enzymatic function results in toxic accumulation of its substrate, a lipid called galactosylsphingosine or `psychosine'. Psychosine cytotoxicity is considered the basis of several key pathologies in GLD. Neuropathology in GLD is marked by profound demyelination and inflammation. However, molecular details of these processes are limited, leaving few therapeutic options. Early histological evidence for CD8+ T cells within demyelinated lesions in both the twi mouse brain and human GLD brain had suggested a role for adaptive immunity in this disease. However, the function of CD8+ T cells in GLD has not been previously determined. To address this gap in our knowledge, we analyzed the timing of T cell population changes by flow cytometry in CNS tissues from the twitcher mouse model of GLD and compared with wt littermates. We identified a rapid and protracted elevation of T cells in the twi CNS that was coincident with the onset of clinical disease at postnatal day 21 (P21). These data were confirmed using single-cell RNA sequencing on twi and wt littermate brain tissues from which identified a 9-fold increase in CD8+ T cells in twi mouse brains at P21. Our transcriptomic data also defined the CD8+ population as cytotoxic T lymphocytes (CTLs). To test the function of CD8+ CTLs in GLD-like disease in twi mice, we depleted CD8+ T cells by administering anti-CD8 antibody to twi mice and found that this treatment effectively prevented disease onset, preserved wellness and completely prevented CNS demyelination while also attenuating pro-inflammatory cytokine levels in brain and blood. These novel and highly translational data portend a pathogenic role for CD8+ T cells in GLD and underlie the basis for our overall hypothesis that CD8+ T cells are pathogenic in GLD and directly contribute to disease. Accordingly, Aim 1 will characterize the spatial and temporal development of CD8+ T cells in twi mice and challenge the contribution of CD8+ T cells using knockout mouse lines to then assess clinical, biochemical, and pathological outcomes. Aim 2 will define the overall nature of adaptive immunity by evaluating contribution of CD4+ T cells to CD8+ T cell-mediated immunity in twi mice using targeted depletion and genetic strategies. Aim 3 will identify and profile the timing, and location T cells responding to authentic antigen, the clonality of the T cells using T cell β chain VDJ phenotyping, and then identify the nature of the antigen presenting cell types using transgenic reporter mice. These multi-disciplinary studies will interrogate a previously unrecognized CD8+ T cell neuroinflammatory response in GLD. Outcomes of these studies are expected to fill an important gap in our understanding on the fundamental cellular pathological mechanisms underlying the development CD8+ T cell mediated neuropathology and disease in GLD.

抽象的球状细胞脑白质营养不良（GLD）或克拉伯氏病是一种遗传性致命的中枢神经脱髓鞘疾病神经系统疾病会影响十分之一的活产儿，且无法治愈或长期有效治疗。通过半乳糖神经酰胺酶 (galc) 基因的功能丧失突变，其中 GALC 酶功能丧失导致其底物（一种称为半乳糖基鞘氨醇或“精神毒碱”的脂质）的毒性积累。细胞毒性被认为是 GLD 中几种关键病理学的基础。然而，这些过程的分子细节有限，导致广泛的脱髓鞘和炎症。两者脱髓鞘病变内 CD8+ T 细胞的早期组织学证据很少。小鼠大脑和人类 GLD 大脑表明适应性免疫在这种疾病中发挥着作用。 CD8+ T 细胞在 GLD 中的功能先前尚未确定。通过流式细胞术分析了 twitcher 小鼠中枢神经系统组织中 T 细胞群变化的时间 GLD 模型并与 wt 同窝小鼠相比，我们发现 T 细胞快速且持久的升高。 twi CNS 与出生后第 21 天（P21）临床疾病的发作一致。使用单细胞 RNA 测序对 twi 和 wt 同窝小鼠脑组织进行证实，从中鉴定出 9 倍 P21 时双胞胎小鼠大脑中 CD8+ T 细胞的增加我们的转录组数据也定义了 CD8+ 群体。作为细胞毒性 T 淋巴细胞 (CTL) 为了测试 CD8+ CTL 在 Twi 小鼠中的 GLD 样疾病中的功能。通过给双胞胎小鼠施用抗 CD8 抗体来耗尽 CD8+ T 细胞，并发现这种治疗有效预防疾病发作，保持健康并完全预防中枢神经系统脱髓鞘，同时还这些新颖且高度转化的数据降低了大脑和血液中的促炎细胞因子水平。预示着 CD8+ T 细胞在 GLD 中的致病作用，并构成了我们总体假设的基础：CD8+ T 细胞在 GLD 中具有致病性并直接导致疾病，因此，目标 1 将描述该疾病的特征。双胞胎小鼠中 CD8+ T 细胞的空间和时间发育并挑战 CD8+ T 细胞的贡献使用基因敲除小鼠系来评估临床、生化和病理结果将定义目标 2。通过评估 CD4+ T 细胞对 CD8+ T 细胞介导的贡献来评估适应性免疫的总体性质使用目标消除和遗传策略对 Twi 小鼠进行免疫，Aim 3 将识别并分析时间，并定位对真实抗原有反应的 T 细胞，使用 T 细胞 β 链 VDJ 确定 T 细胞的克隆性表型分析，然后使用转基因报告小鼠鉴定抗原呈递细胞类型的性质。这些多学科研究将探究以前未被识别的 CD8+ T 细胞神经炎症这些研究的结果预计将填补我们对 GLD 理解的一个重要空白。 CD8+ T 细胞介导的发育的基本细胞病理机制 GLD 中的神经病理学和疾病。