Global spinal cord trophic factor delivery using intracerebral rAAV in ALS rats

描述(申请人提供)：肌萎缩侧索硬化症(ALS)是一种进行性和致命性的神经系统疾病，其特征是上下部运动神经元死亡。目前还没有已知的治疗方法。我们团队有在神经系统疾病的动物模型中使用病毒载体传递蛋白质的经验，并已在其他医学适应症上进行了临床试验。最近的报道表明，胶质细胞源性神经营养因子(GDNF)和胰岛素样生长因子1(IGF1)是可能有效治疗ALS的营养因子。然而，由于肌萎缩侧索硬化症是进行性的，需要长期的蛋白质输送。此外，受影响的运动神经元分布在整个脊髓的前角。慢性递送和全球脊髓递送是蛋白质递送的主要挑战。该项目的目标是使用腺相关病毒载体，注射在单个脑区，通过已知的解剖脊髓投射束顺行运输，将分泌的营养因子GDNF和IGF1运送到整个脊髓。本研究的总体假设是，无论是运动皮质的锥体细胞还是红核的神经元，都可以通过重组腺相关病毒载体(RAAV)永久性地转导产生GDNF和IGF1，并且这些蛋白可以以治疗性的方式输送到整个脊髓。因此，我们提出两个目标：1)在正常大鼠的红核内注射rAAV1、rAAV5和rAAV8，以确定报告基因、绿色荧光蛋白(GFP)、IGF1和GDNF顺行转运的效率、持续时间和安全性。以优化脊髓基因产品的输送。2)检测rAAV介导的GDNF和IGF1在肌萎缩侧索硬化症大鼠模型中拯救下运动神经元疾病的可能性。救援将通过评估对照组和ALS大鼠运动症状的进展以及脊髓的详细组织病理学来确定。目前的建议可能会产生大量关于载体介导的蛋白质传递到整个脊髓的一般信息。这些数据可能对脊髓损伤特别是ALS有普遍意义。

DESCRIPTION (provided by applicant): Amyotrophic Lateral Sclerosis (ALS) is a progressive and lethal neurological disorder characterized by death of upper and lower motoneurons. There is no known cure. Our group has experience using viral vectors to deliver proteins in animal models of neurological disorders and have proceeded to clinical trials in other medical indications. Recent reports indicate that glial cell line- derived neurotrophic factor (GDNF) and insulin-like growth factor 1 (IGF1) are trophic factors that may be efficacious in treating ALS. However, since ALS is progressive, chronic protein delivery will be needed. Moreover, the affected motoneurons are distributed in the ventral horn of the entire spinal cord. Chronic delivery and global spinal cord delivery are major challenges for protein delivery. The goal of this project is to use recombinant adeno-associated viral vectors, injected in single brain regions, to deliver the secreted trophic factors GDNF and IGF1 to the entire spinal cord, by using anterograde transport via known anatomical spinal projecting tracts. The overall hypothesis of the present proposal is that either the pyramidal cells of the motor cortex or the neurons in the red nucleus can be permanently transduced by recombinant adeno-associated viral vectors (rAAV) to produce GDNF and IGF1 and these proteins can be delivered to the entire spinal cord in a therapeutic manner. Therefore, two aims are proposed: 1) To determine the efficiency, duration and safety of anterograde transport of the reporter gene, green fluorescent protein (GFP), IGF1, and GDNF after injection of rAAV1, rAAV5 and rAAV8 into the red nucleus in normal rats. In order to optimize spinal cord delivery of gene products. 2) To examine the potential for rescue of lower motor neuron disease in an amyotrophic lateral sclerosis rat model using rAAV-delivered GDNF and IGF1. Rescue will be determined both by evaluating the progression of the motor symptoms in control and ALS rats and by detailed histopathology of the spinal cord. The present proposal is likely to produce a significant amount of general information about vector-mediated protein delivery to the entire spinal cord. These data may have general implications for spinal cord injuries and ALS in particular.