Gene Therapy for Pain

描述（由申请人提供）：在过去的五十年中，神经科学界在我们对脊髓背角和背根神经节（DRG）的组织和功能的理解方面取得了重大进展。许多新的蛋白质已被鉴定为在疼痛信号传导通路中的重要蛋白质。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）血清型已显示可用于皮层、脑干和小脑中的神经元的转导。其用于脊髓和背根神经节中的神经元转导的效用也已被探索;将AAV载体递送至脊髓或DRG的尝试仅通过直接实质内或神经内注射成功。微创和更具临床治疗性的直接腰椎穿刺方法尚未成功转导脊髓。相比之下，我们现在已经成功地实现了广泛的脊髓和DRG转导的标志物绿色荧光蛋白（GFP）的直接腰椎穿刺注射的AAV血清型5（AAV 5）在清醒的小鼠和大鼠。这些初步研究支持我们的建议，以优化递送和表征基于AAV 5的载体的潜在功能，所述载体靶向已知调节脊髓或DRG内慢性疼痛信号传导的特定基因。高效的AAV 5介导的遗传操作提供了大量的机会，以1）进一步研究慢性疼痛的潜在机制，和2）开发新的基于基因的疗法，用于使用具有确定的安全裕度的非侵入性递送途径治疗和管理慢性疼痛。拟议的研究将评估通过腰椎穿刺递送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递送选择的效用。该项目的主要目的是：1）优化向脊髓和DRG的递送并表征AAV 5-GFP构建体的分布。2)为了验证这种方法，在一个系统中建立了疼痛信号传导通路。3)将该方法应用于一种新的非阿片系统，该系统可能对慢性阿片耐受的发展和慢性疼痛的维持施加控制。鞘内递送AAV 5构建体的未来应用将增强对在脊髓和DRG水平参与慢性疼痛的其他新靶点的研究，并可能实现慢性疼痛治疗的转化发展。

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.