Intrathecal Gene Therapy Expressing IGF-1 for Amyotrophic Lateral Sclerosis

肌萎缩侧索硬化症(ALS)是一种破坏性的神经肌肉疾病，每40,000人中就有1人发病 每年。肌萎缩侧索硬化症患者表现出肌肉控制能力的迅速丧失、肌肉萎缩和死于 呼吸衰竭。肌萎缩侧索硬化症的原因是运动神经元对肌肉的渐进性失神经。的确有 目前还没有治愈这种疾病的方法，唯一被批准的治疗方法对这种疾病的效果非常温和 进步。显然，迫切需要更有效的治疗方法。一条可能的路线是 使用神经保护因子，由于它们的一般作用方式，可能对其他神经肌肉有用 疾病也是如此。我们这个项目的长期目标是开发ALS的基因疗法。以前的研究 已经调查了神经保护因子的使用情况。这些分子，如胰岛素样生长因子1 胰岛素样生长因子-1(IGF-1)为运动神经元提供抗凋亡信号，并促进轴突生长。这些 分子在动物研究中似乎很有前途。然而，临床试验表明，将剂量扩大到 人类构成了令人生畏的挑战。一种更有效的方法可能是使用基因疗法来允许 患者自身细胞产生的治疗因子。几项研究，包括我们自己的研究，已经证明了这一点 这种方法有其可取之处。然而，这些研究使用的技术并没有在更大的动物身上得到很好的推广。 模特们。脊髓实质内注射只导致局部转基因表达，因此 将需要在人体内进行不合理的大量注射。运动神经元的逆行运输 肌肉注射载体对ALS啮齿动物模型也有效，但同样可能有限 由于需要注射的肌肉质量，临床适用性。在这份提案中，我们将调查 鞘内注射表达IGF-1的基因治疗ALS大鼠模型的疗效在……里面 具体目标1，我们证明了我们的基因疗法可以促进运动神经元的存活，并保护运动神经元的完整性 神经肌肉接头。此外，我们将展示这种疗法减弱星形胶质细胞的激活和 有助于破坏运动神经元的小胶质细胞。此外，我们将调查 运动神经元对升高的IGF-1水平产生耐受性的可能性，这一现象可能限制 这种疗法的疗效是长期的。在具体的目标2中，我们将展示在AIM中发现的改进 1转化为改善运动功能和延长寿命。SOD1大鼠将使用GRIP进行评估 力量、旋转和开阔场地测试，以评估运动功能的几个方面。另外，寿命，年龄 在疾病开始时，将测量疾病进展率以显示疗效。这项研究将 提供必要的原则证明数据，以支持该方法未来的临床试验。

Amyotrophic lateral sclerosis (ALS) is a devastating neuromuscular disorder striking about 1 person in 40,000 each year. Individuals with ALS exhibit rapid loss of muscle control, muscle atrophy, and death due to respiratory failure. The cause of ALS is the progressive denervation of muscle by motor neurons. There is currently no cure for this disease, and the only approved therapy has a very modest effect on the disease progression. Clearly, there is a pressing need for more effective therapies. One possible route would be to use neuroprotective factors which, due to their general mode of action, may have utility in other neuromuscular disorders as well. Our long-term objective for this project is to develop gene therapy for ALS. Previous studies have investigated the use of neuroprotective factors. These molecules, such as insulin-like growth factor 1 (IGF-1) provide anti-apoptotic signals for motor neurons as well as promoting neurite outgrowth. These molecules seemed promising in animal studies. However, clinical trials demonstrated that scaling the dose to humans poses daunting challenges. A more effective approach might be to use gene therapy to allow the patients' own cells to produce the therapeutic factor. Several studies, including our own, have shown this approach has merit. However, these studies used techniques that have not scaled up well in larger animal models. Intraparenchymal injection into the spinal cord results in only localized transgene expression and thus would require an unreasonably large number of injections in humans. Retrograde transport in motor neurons of vector injected into muscle was also effective in a rodent model of ALS, but again would likely have limited clinical applicability due to the muscle mass that would need to be injected. In this proposal we will investigate efficacy of intrathecally administered gene therapy expressing IGF-1 in the SOD1-G93A rat model of ALS. In Specific Aim 1, we show that our gene therapy can promote motor neuron survival and protect the integrity of neuromuscular junctions. In addition we will show that this therapy attenuates the activation of astrocytes and microglia that helps contribute to the destruction of motor neurons. Furthermore, we will investigate the possibility that motor neurons can develop tolerance to elevated levels of IGF-1, a phenomenon that could limit the effectiveness of this therapy long-term. In Specific Aim 2, we will show that the improvements found in Aim 1 translate into improved motor function and increased life span. SOD1 rats will be evaluated using the grip strength, rotarod, and open field tests to evaluate several aspects of motor function. In addition, life span, age at disease onset, and the rate of disease progression will be measured to show efficacy. This study will provide the proof-of-principle data necessary to support future clinical trials of this approach.