Developing a drug-inducible gene therapy for temporal lobe epilepsy

开发药物诱导的颞叶癫痫基因疗法

基本信息

批准号：
10800000
负责人：
EDWARD PEREZ-REYES
金额：
$ 53.15万
依托单位：
UNIVERSITY OF VIRGINIA
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-07-01 至 2025-04-30
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10800000
关键词：
Address Affect Agonist American Animal Model Anticonvulsants Basic Science Brain region Cells Characteristics Clinical Collaborations Convulsants Development Disease Dose Doxycycline Drug Screening Electric Stimulation Elements Enhancers Environment Epilepsy Equilibrium FDA approved Frequencies Gene Expression Goals Grant Hippocampus Hybrids Immune Kainic Acid Learning Maps Medical Medicine Memory Modeling Motor Seizures Mouse Strains Mus Neuromodulator Neurons Partial Epilepsies Patients Persons Pharmaceutical Preparations Pharmacotherapy Potassium Channel Randomized Recurrence Reproducibility Research Research Design Rodent Model Safety Seizures Side Site Sleep Structure System Technology Temporal Lobe Epilepsy Testing Universities Viral Vector antagonist clinical translation design drug development efficacy study excitatory neuron forest gamma-Aminobutyric Acid gene product gene therapy immunocytochemistry inhibitory neuron insight miniaturize neural circuit neuronal circuitry next generation novel overexpression preclinical study promoter side effect success targeted treatment

项目摘要

There are 3 million Americans with epilepsy. This research aims to develop a first-in-class drug- inducible gene therapy for the most common form of focal epilepsy, temporal lobe epilepsy (TLE). TLE affects half a million Americans, yet despite the size of this problem, medical treatment of TLE fails in a third of these patients. Clearly there is a large unmet clinical need for a treatment without side effects. The guiding hypothesis of these studies is that TLE is a circuit-based disease, requiring the development of next-generation gene therapies that target these circuits. Key technological advances made to address this hypothesis include: 1) development of novel animal models of TLE with spontaneous seizure characteristics that are amenable to drug screening; 2) mapping epileptic circuits using activity-dependent promoters; and 3) development of drug-inducible gene therapies that target specific circuits. It was discovered that electrical stimulation of a specific strain of mouse (VGAT-Cre) was sufficient to trigger limbic epilepsy. To extend the model to other strains of mice, electrical stimulation was combined with a chemoconvulsant, kainic acid. This hybrid approach effectively triggered spontaneous seizures in commonly used mouse strains, such as C57Bl/6. Importantly, the hybrid approach opened the door for studies using the TRAP2 strain, which has proven useful for circuit mapping studies. The drug-inducible gene therapy uses the well-established doxycycline (Dox) regulated system. The technological challenges were to miniaturize this system so it fits in viral vectors, reduce gene expression in the absence of the inducer (leak), and develop a toolkit of promoters to target neuronal subtypes. The goal is to develop a Dox-On system where Dox administration reduces seizures and that possible side effects can be reduced by lowering the Dox dose. Reducing leak to background levels is an important safety feature that has yet to be incorporated in any FDA-approved gene therapy. The mechanisms of action of many current antiseizure drugs are to either reduce the activity of excitatory neurons or enhance the activity of inhibitory neurons. By developing gene therapies that selectively target these types of neurons, the proposed studies will compare these two approaches. Key metrics for these therapies are to show they reduce spontaneous seizure frequency by 50% and target specific nodes in the epileptic circuit. Efficacy studies will use rigorous preclinical study designs with blinding, reproducibility, and target engagement. Contributing to the success of this study is a rich environment for clinical translation of basic research in animal models of epilepsy.

有 300 万美国人患有癫痫症。这项研究旨在开发一种一流的药物针对最常见形式的局灶性癫痫——颞叶癫痫（TLE）的诱导基因疗法。 TLE 影响了 50 万美国人，尽管这个问题很严重，但 TLE 的治疗却失败了其中三分之一的患者。显然，对于无副作用的治疗，临床需求还有很大的未得到满足。这些研究的指导性假设是 TLE 是一种基于回路的疾病，需要开发针对这些回路的下一代基因疗法。关键技术进展为解决这一假设而做出的努力包括：1）开发新的 TLE 动物模型适合药物筛选的自发性癫痫发作特征； 2）绘制癫痫回路图使用活性依赖性启动子； 3）开发靶向药物诱导的基因疗法具体电路。研究发现，对特定品系小鼠（VGAT-Cre）进行电刺激足以引发边缘叶癫痫。为了将该模型扩展到其他品系的小鼠，电刺激与化学惊厥剂红藻氨酸结合使用。这种混合方法有效地引发常用小鼠品系（例如 C57Bl/6）的自发性癫痫发作。重要的是，混合方法为使用 TRAP2 菌株进行研究打开了大门，该菌株已被证明对电路有用测绘研究。药物诱导基因疗法使用成熟的多西环素 (Dox) 监管系统。技术挑战是使该系统小型化，使其适合病毒载体，在没有诱导物（泄漏）的情况下减少基因表达，并开发启动子工具包目标神经元亚型。目标是开发一个 Dox-On 系统，减少 Dox 管理癫痫发作，并且可以通过降低阿霉素剂量来减少可能的副作用。减少泄漏至背景水平是一项重要的安全特性，尚未纳入 FDA 批准的任何产品中基因疗法。目前许多抗癫痫药物的作用机制是减少癫痫发作兴奋性神经元的活性或增强抑制性神经元的活性。通过开发基因选择性针对这些类型神经元的疗法，拟议的研究将比较这两种接近。这些疗法的关键指标是表明它们可以降低自发性癫痫发作频率 50% 并针对癫痫回路中的特定节点。功效研究将使用严格的临床前研究设计具有盲法、可重复性和目标参与度。为本次活动的成功做出了贡献研究为癫痫动物模型基础研究的临床转化提供了丰富的环境。