Gene therapy for Alzheimer's disease using virally delivered Aβ variants

使用病毒传递的 Aβ 变体进行阿尔茨海默氏病的基因治疗

基本信息

批准号：
10316624
负责人：
JOANNA L JANKOWSKY
金额：
$ 178.83万
依托单位：
BAYLOR COLLEGE OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-08-15 至 2024-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10316624
关键词：
APP-PS1 Aducanumab Adult Aftercare Age Alzheimer&apos s Disease Alzheimer&apos s disease brain Alzheimer&apos s disease therapy Amyloid Amyloid beta-Protein Antibodies Base Sequence Biophysical Process Birth Brain Cell Line Cell membrane Chromatography Chronic Circular Dichroism Spectroscopy Data Dependovirus Disease Disease Marker Disease Progression Electron Microscopy Engineering Extracellular Space Gene Expression Profiling Gene Transduction Agent Genes Growth Half-Life Histologic Human Immune Immune response Impaired cognition In Vitro Inflammation Injections Knock-in Mouse Life Measures Memantine Molecular Sieve Chromatography Morphology Mus Neuroimmune Neurons Outcome Penetration Peptide Hydrolases Peptides Pharmaceutical Preparations Phase Prevention Preventive treatment Reaction Research Route Safety Seeds Severities Spectrum Analysis Structure Surveys Technology Testing Therapeutic Therapeutic Uses Toxic effect Transgenic Mice Tube Variant Viral Work abeta accumulation abeta toxicity adeno-associated viral vector amyloid pathology analytical method antibody engineering base blood-brain barrier penetration cognitive function comparison intervention cost dosage expression vector gamma secretase gene therapy in vivo inflammatory marker inhibitor/antagonist mouse model neonatal brain nervous system disorder novel phase III trial pre-clinical prevent protein misfolding response tau Proteins therapeutic candidate therapeutic evaluation tool transduction efficiency

项目摘要

SUMMARY The continuing saga of anti-Ab antibody aducanumab has produced the first positive phase 3 outcome for Alzheimer's disease (AD) since memantine was approved in 2003. This promising, albeit controversial, result has breathed new life into the therapeutic potential for Ab-lowering strategies and legitimized the ongoing exploration of other means to chronically and safely mitigate Ab. Past work had shown that small peptide inhibitors can be readily tailored to prevent Ab aggregation, but in vivo delivery of peptide-based drugs was limited by short half-life and poor brain penetration. We have identified two Ab sequence variants that meet criteria for potential therapeutic use, as they 1) prevent aggregation of WT Ab in vitro, 2) promote disassembly of Ab existing fibrils, 3) mitigate toxicity of Ab oligomers, and importantly, 4) do not self-aggregate. To deliver these peptides in vivo, we have developed a novel mini-gene to express our variant peptides at the plasma membrane where they are released into the extracellular space by g-secretase cleavage. By packaging this minigene into an AAV vector that is injected into APP/PS1 mice, our pilot data show that viral expression of variant Ab lowers Ab load and delays plaque formation. The current proposal will build on these results through the following specific aims. First, we will decipher the biophysical mechanism of interactions between variant and wild type Aβ peptides. We will use analytical methods of CD spectroscopy, SEC chromatography, EM, and antibody profiling to define the structural mechanism by which our variants prevent/reverse aggregation of wild-type Ab. Second, we will determine how dosage, timing and route of variant Aβ administration influence efficacy in vivo. We will use viral strategies to compare interventional treatment after amyloid onset with preventative treatment starting at birth, determine the lowest effective ratio of variant:wild- type Ab needed to modify plaque formation and cognitive function, and test whether delivery through the CSF can match the effect of neuronal transduction. Third, we will interrogate the neuroimmune reaction to variant Aβ as an accomplice to plaque reduction. We will use histological and transcriptional profiling to assess whether a neuroimmune response to either the variant peptide or its AAV carrier contribute to plaque prevention in vivo, and if the neuroimmune response changes with age. Finally, we will test the potential for variant Aβ to slow AD aggregate seeding. We anticipate that variant Ab will slow seeding by AD Ab extracts, but will more importantly test whether variant Ab can assuage cross-seeding of tau in amyloid-bearing mice. If successful, this strategy for self-inhibition may also be applicable to other protein misfolding diseases where peptide treatments have been eschewed for technical reasons that can now be overcome through expression engineering and viral technology.

概括抗AB抗体aducanumab的持续传奇已经产生了第一个正阶段3结果自从梅米恩丁（Memantine）于2003年获得批准以来，阿尔茨海默氏病（AD）。这一承诺，尽管有争议，但结果已经为减少AB的策略带来了新的生活潜力，并使正在进行的策略合法化探索其他方法，以慢性和安全地减轻AB。过去的工作表明小胡椒抑制剂可以轻松量身定制以防止AB聚集，但体内递送基于肽的药物是受到半衰期和大脑穿透不良的限制。我们已经确定了两个满足的AB序列变体潜在治疗用途的标准，因为它们1）防止在体外汇总WT AB，2）促进拆卸在现有的原纤维中，3）减轻AB低聚物的毒性，重要的是，4）不要自我聚集。交付这些在体内的宠物，我们开发了一种新颖的迷你基因来表达我们在等离子体的变体膜通过G-分泌酶的裂解将它们释放到细胞外空间中。通过包装在AAV矢量中注入APP/PS1小鼠的AAV矢量，我们的试验数据表明，病毒表达变体AB降低AB负载并延迟牙菌斑的形成。当前的建议将基于这些结果通过以下特定目标。首先，我们将破译相互作用的生物物理机制变体和野生型AβPeperides。我们将使用CD光谱，SEC色谱法的分析方法， EM和抗体分析以定义我们的变体阻止/反向的结构机制野生型AB的聚集。其次，我们将确定剂量，时机和变体AB的途径如何管理影响体内的效率。我们将使用病毒策略来比较淀粉样蛋白发作从出生开始时进行预防治疗，确定变体的有效比率最低：野生修改斑块形成和认知功能所需的AB类型，并测试是否通过CSF进行交付可以匹配神经元转移的效果。第三，我们将询问对变体的神经免疫反应 Aβ作为减少牙菌斑的收购。我们将使用组织学和转录分析来评估对变异肽或其AAV载体的神经免疫反应是否有助于斑块在体内预防，如果神经免疫反应随着年龄的增长而变化。最后，我们将测试潜力变体Aβ减慢AD聚集播。我们预计变体AB会减慢AD AB提取物的播种，但是，更重要的是，将测试变体AB是否可以在淀粉样小鼠中缓解tau的交叉种子。如果成功，这种自我抑制策略也可能适用于其他蛋白质错误折叠疾病由于技术原因，已经避免了肽治疗，现在可以通过表达工程和病毒技术。