Gene Therapy for Pain

描述(申请人提供)：在过去的五十年里，神经科学界在我们对脊髓背角和背根神经节(DRG)的组织和功能的了解方面取得了重大进展。许多新的蛋白质被发现在疼痛信号传导通路中起重要作用。新的基因治疗方法可能为长期疼痛管理策略提供新的机会。腺相关病毒(AAV)的血清型已被证明对皮质、脑干和小脑的神经元转导有用。它在脊髓和背根神经节的神经元转导中的作用也得到了探索；将AAV载体运送到脊髓或DRG的尝试只有通过直接实质内或神经内注射才能成功。侵入性较小、临床疗效较好的直接腰椎穿刺法尚未成功地传导至脊髓。相比之下，我们现在已经成功地通过腰穿直接注射AAV 5型(AAV5)在清醒的小鼠和大鼠中实现了标记绿色荧光蛋白(GFP)的广泛脊髓和DRG转导。这些初步研究支持我们的建议，即优化AAV5载体的传递并鉴定其潜在功能，该载体针对特定的已知基因，可调节脊髓或DRG内的慢性疼痛信号。高效的AAV5介导的基因操作提供了大量的机会来1)进一步研究慢性疼痛的潜在机制，以及2)开发基于基因的新疗法，使用具有既定安全边际的非侵入性递送途径来治疗和管理慢性疼痛。这项拟议的研究将评估通过腰椎穿刺法输送AAV载体作为慢性疼痛基础科学研究的有用工具以及潜在的治疗输送选择。该项目的主要目标是：1)优化向脊髓和背根节的递送，并确定AAV5-GFP结构的分布。2)为了验证这种方法，在疼痛信号传导通路中建立了一个良好的系统。3)将该方法应用于一种新的非阿片类药物系统，该系统可能对慢性阿片类药物耐受的发展和慢性疼痛的维持施加控制。鞘内注射AAV5构建物的未来应用将加强在脊髓和背根节水平参与慢性疼痛的其他新靶点的研究，并可能使慢性疼痛治疗的翻译开发成为可能。

DESCRIPTION (provided by applicant): Over the past five decades, the neuroscientific community has made significant progress in our understanding of the organization and function of the spinal cord dorsal horn and dorsal root ganglia (DRG). Many new proteins have been identified as important in the pain signal conduction pathway. Novel gene therapy approaches may offer new opportunities for long-term pain management strategies. The adeno-associated virus (AAV) serotype has been shown to be useful for transduction of neurons in cortex, brainstem, and cerebellum. Its utility for transduction of neurons in the spinal cord and dorsal root ganglia has also been explored; attempts to deliver the AAV vectors to the spinal cord or DRG have only been successful with direct intraparenchymal or intraneural injections. Less invasive and more clinically therapeutic direct lumbar puncture approaches have not successfully transduced the spinal cord. In contrast, we have now succeeded in achieving widespread spinal cord and DRG transduction of the marker green fluorescent protein (GFP) by direct lumbar puncture injection of an AAV serotype 5 (AAV5) in conscious mouse and rat. These preliminary studies support our proposal to optimize delivery and characterize potential function of AAV5 based vectors targeting specific genes known to modulate chronic pain signaling within spinal cord or DRG. Efficient AAV5-mediated genetic manipulation offers substantial opportunities to 1) further study mechanisms underlying chronic pain and 2) develop novel gene-based therapies for the treatment and management of chronic pain using a non-invasive delivery route with established safety margins. The proposed research will assess the utility of delivery of AAV-vector by lumbar puncture as a useful tool for basic scientific study of chronic pain as well as a potential therapeutic delivery option. The primary objectives of the project are: 1) To optimize delivery to the spinal cord and DRG and characterize the distribution of the AAV5-GFP construct. 2) To validate this approach, in a system well established in the pain signal conduction pathway. 3) To apply the approach to a novel non-opioid system that may exert control on the development of chronic opioid tolerance and maintenance of chronic pain. Future applications of intrathecal delivery of AAV5 constructs will enhance study of other novel targets participating in chronic pain at the level of the spinal cord and DRG and may enable translational developments of chronic pain therapies.