The Progranulin C-Terminal Domain and AAV-Progranulin Gene Therapy for Frontotemporal Dementia

颗粒体蛋白前体 C 端结构域和 AAV-颗粒体蛋白前体基因治疗额颞叶痴呆

基本信息

批准号：
10671655
负责人：
Shreya Kashyap
金额：
$ 4.87万
依托单位：
UNIVERSITY OF ALABAMA AT BIRMINGHAM
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-09-01 至 2024-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10671655
关键词：
Ablation Alleles Amino Acids Anti-Inflammatory Agents Antibodies Antigen-Presenting Cells Behavioral Binding Binding Sites Biological Assay Biology Blood Brain C-terminal Carboxy-Lyases Cells Cervical lymph node group Critical Thinking Data Dementia Dendritic Cells Detection Disease Doctor of Medicine Doctor of Philosophy Effectiveness Environment Enzyme-Linked Immunosorbent Assay Epitopes Foundations Frontotemporal Dementia Functional disorder Genes Gliosis Glycoproteins Goals Growth Factor Heterozygote Human Immune Immune response Immunohistochemistry In Situ Hybridization In Vitro Label Language Disorders Loss of Heterozygosity Lysosomes Macrophage Measures Mediating Mentors Microdialysis Microglia Modification Mus Mutation N-terminal Neurodegenerative Disorders Neuroimmune Neurons PGRN gene Parkinson Disease Pathogenesis Pathology Patients Phenotype Physicians Predisposition Property Proteins Rodent Model Role Scientist Small Interfering RNA Social Behavior Solid System T-Cell Activation Testing Therapeutic Training Translational Research Tube Work aged career cellular transduction clinical translation design doctoral student dosage early onset enzyme activity experimental study extracellular gene therapy immunogenic immunogenicity improved in vivo interstitial loss of function mutation mouse model neuroinflammation novel therapeutics particle prevent receptor research clinical testing skills social sortilin success trafficking translational approach uptake vector

项目摘要

Project Summary This application is for F30 support of Shreya Kashyap during her MD/PhD training. The scientific focus of this proposal is to determine the role of the progranulin C-terminal domain (CTD) on AAV-derived progranulin levels in vivo and the effectiveness of AAV-Progranulin gene therapy. Heterozygous loss of function mutations in the progranulin gene (GRN) are one cause of frontotemporal dementia (FTD), a devastating neurodegenerative disease characterized by social behavior and language deficits. Work from the lab of Dr. Erik Roberson, sponsor of the PI, has established the therapeutic potential of AAV-Progranulin gene therapy in progranulin-insufficient mouse models of FTD. The vector used for these experiments has a tag fused to the CTD that precludes progranulin's interaction with its canonical trafficking receptor, sortilin. These experiments show that the lysosomal localization and efficacy of AAV-Progranulin is independent of sortilin. However, the functional consequences of an exposed progranulin CTD, which allows for progranulin-sortilin binding, are still unknown. Notably, sortilin mediates the uptake and degradation of progranulin and sortilin ablation or inhibition boosts both brain and CSF progranulin levels in wild type and progranulin-insufficient mouse models. My preliminary experiments indicate that blocking the progranulin C-terminal domain boosts parenchymal levels of AAV-derived progranulin, and improves efficacy of AAV-Progranulin in rescuing lysosomal pathology and neuroinflammation. The clinical translation of AAV-Progranulin vectors with tags fused to the progranulin CTD is unlikely. Thereby, it is important to determine CTD sequence modifications that improve dosage and levels of AAV-Progranulin. Immune mediated clearance of AAV particles and AAV-transduced cells reduce the effectiveness of AAV- based gene therapies. Progranulin-deficient mice mount an immune response to AAV-murine progranulin, and it is unclear if FTD-GRN patients (who have one functioning progranulin allele) will mount an immune response to AAV-human progranulin. However, as evidenced by recent clinical testing of AAV-glial derived neurotrophic growth factor (AAV-GDNF) and AAV-amino acid decarboxylase (AAV-AADC) in patients with Parkinson's disease, patients can mount immune responses even to AAV-derived proteins with non-foreign epitopes. Thus, it is important to identify sequence modifications that reduce immune cell uptake of secreted AAV-derived progranulin. Because sortilin is expressed by various antigen presenting cells in the brain, blocking the progranulin-sortilin interaction has the potential to decrease the immunogenicity of AAV-Progranulin vectors. The proposed training plan for Shreya Kashyap is sponsored by her project mentor, Dr. Erik Roberson. The overall goal of the training plan is to provide the PI with a solid foundation for a successful career as a physician scientist. A project based both in translational approaches, while focused on a disease-oriented pathogenesis, is the ideal training environment for any aspiring physician scientist.

项目摘要该应用程序是为Shreya Kashyap在MD/PhD培训期间的F30支持。科学重点提案是确定前素蛋白C末端结构域（CTD）对AAV衍生的pRogranulin水平的作用体内和AAV生素蛋白基因疗法的有效性。功能突变的杂合丧失促素蛋白基因（GRN）是额颞痴呆（FTD）的原因，这是一种毁灭性的神经退行性的原因以社会行为和语言缺陷为特征的疾病。赞助商Erik Roberson博士的实验室工作 PI的aav-性蛋白基因疗法在易生素蛋白不足的情况下建立了治疗潜力 FTD的鼠标模型。这些实验使用的向量具有与CTD融合的标签，可排除促素蛋白与其规范运输受体Tortilin的相互作用。这些实验表明 AAV-生育蛋白的溶酶体定位和功效独立于Tortilin。但是，功能暴露的尿素蛋白CTD的后果仍然未知。值得注意的是，Tortilin介导了前体蛋白和分子蛋白消融或抑制作用的摄取和降解都可以增强野生型和足够的小鼠模型中的脑和CSF前素水平。我的初步实验表明，阻断易生蛋白C末端结构域可提高AAV衍生的实质水平促生蛋白，并提高AAV杂化蛋白在营救溶酶体病理学和神经炎症方面的功效。 AAV杂化素载体的临床翻译与融合到前素蛋白CTD的标签的临床翻译不可能。从而，确定改善剂量和AAV生物素水平的CTD序列修饰很重要。免疫介导的AAV颗粒和AAV转导细胞的清除率降低了AAV-的有效性基因疗法。缺陷型小鼠对AAV-羟基植物蛋白的免疫反应，并且目前尚不清楚FTD-GRN患者（具有一个功能性的progranulin等位基因）是否会安装免疫反应到AAV-HUMAN PROGRANULIN。然而，正如最近对AAV胶质衍生神经营养的临床测试所证明的。帕金森氏病患者的生长因子（AAV-GDNF）和AAV-氨基酸脱羧酶（AAV-AADC）疾病，即使对具有非外国表位的AAV衍生蛋白的患者也可以进行免疫反应。因此，重要的是确定序列修饰，以减少分泌AAV衍生的免疫细胞摄取的摄取前植物。因为Tortilin是由大脑中各种抗原呈现细胞表达的，从而阻止了前素蛋白 - 替代蛋白的相互作用具有降低AAV杂化素载体的免疫原性的潜力。 Shreya Kashyap拟议的培训计划由她的项目导师Erik Roberson博士赞助。这培训计划的总体目标是为PI为成功的职业提供稳固的基础科学家。一个基于翻译方法的项目，虽然专注于面向疾病的发病机理，但是任何有抱负的医师科学家的理想培训环境。