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积极的 3 期结果自 2003 年美金刚获批以来，阿尔茨海默病 (AD) 一直备受关注。这一结果充满希望，但也可能存在争议为 Ab-lowering 策略的治疗潜力注入了新的活力，并使正在进行的治疗合法化探索其他长期、安全缓解抗体的方法过去的工作表明，小肽。抑制剂可以很容易地定制以防止抗体聚集，但基于肽的药物的体内递送是受到半衰期短和脑渗透性差的限制，我们已经确定了两种符合的抗体序列变体。潜在治疗用途的标准，因为它们 1) 防止 WT Ab 体外聚集，2) 促进分解 Ab 现有原纤维的数量，3) 减轻 Ab 寡聚物的毒性，重要的是，4) 不会自我聚集。这些肽在体内，我们开发了一种新的迷你基因来在血浆中表达我们的变体肽膜，通过 g-分泌酶裂解将其释放到细胞外空间。将小基因导入注射到 APP/PS1 小鼠的 AAV 载体中，我们的试验数据表明，病毒表达变体抗体降低抗体负载并延迟斑块形成当前的提议将建立在这些结果的基础上。首先，我们将破译之间相互作用的生物物理机制。我们将使用 CD 光谱法、SEC 色谱法、 EM 和抗体分析来定义我们的变体预防/逆转的结构机制其次，我们将确定变体 Aβ 的剂量、时间和途径。我们将使用病毒策略来比较介入治疗后的效果。淀粉样蛋白发作从出生开始进行预防性治疗，确定变体：野生型的最低有效比率需要改变斑块形成和认知功能的抗体，并测试是否通过脑脊液传递第三，我们将探讨对变异的神经免疫反应。 Aβ 作为斑块减少的帮凶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会导致斑块体内预防，以及神经免疫反应是否随年龄变化。最后，我们将测试其潜力。变体 Aβ 会减缓 AD 聚集播种，我们预计变体 Ab 会减缓 AD Ab 提取物的播种，但更重要的是测试变体 Ab 是否可以减轻 tau 蛋白在携带淀粉样蛋白的小鼠中的交叉接种。如果成功的话，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，其中由于技术原因，肽治疗一直受到质疑，现在可以通过以下方式克服：表达工程和病毒技术。