Next Generation Gene Therapy for Refractory Pain

项目摘要 在美国，慢性疼痛影响着2500多万成年人，是导致残疾的主要原因。目前 现有的疼痛治疗方法，如阿片类药物，往往是无效的，并伴随着不可接受的副作用 包括呼吸抑制和上瘾。新的疼痛疗法的一个主要目标是抑制感觉 选择性地传递疼痛信号(伤害性感受器)的神经元，而不影响参与 无害的感觉或中枢神经系统。然而，针对伤害性感受器的治疗方法 仍处于初级阶段。基于病毒的基因疗法在治疗顽固性疼痛方面有几个吸引人的优势， 因为病毒可以被设计成传递广泛的分子，可以局部或系统地给药， 最近已被食品和药物管理局批准用于一些适应症。然而， 伤害性感受器特异性病毒工具目前还不存在，这在很大程度上是由于感觉的异常异质性 神经元，这使得识别这些细胞独有的分子特征变得困难。最新进展 在单细胞基因组学中，已经使我们能够生成一份细胞图谱，描述选择性地 在老鼠和人类的伤害性感受器中表达。这一建议旨在揭示内源基因的调控 介导伤害性感受器特异性基因表达模式的元件，并将这些元件改造成条形码 腺相关病毒库。为此，我们提出了以下具体目标：1)映射 小鼠和人伤害性感受器特异性基因调控元件和2)伤害性感受器特异性基因调控元件的产生 AAV工具包。我们在这项提案中开发的伤害性感受器特异性病毒将立即对科学 在野生型小鼠和可能的其他物种中访问伤害感受器的社区。另外，因为我们会 优先考虑在老鼠和人类伤害性感受器之间保守的基因调控元件，我们持乐观态度 我们在老鼠身上筛选的病毒也将在人类中驱动伤害性感受器特异性基因的表达。接下来是这些 新一代针对伤害性感受器的基因疗法非常适合于治疗某些顽固性疼痛障碍。 因为它们可以通过标准的门诊程序局部注射到神经病理性感觉神经节 并且可以被设计成驱动离子通道的表达，该离子通道仅在存在的情况下沉默伤害性感受器的活动 一种特定的药物(化学遗传学)。这种无阿片类药物的方法可能会有重大的翻译应用 对于患有顽固性慢性疼痛的患者，他们往往没有其他缓解的选择。

Project Summary Chronic pain affects over 25 million adults in the United States and is a major cause of disability. Currently available pain treatments such as opioids are often ineffective and associated with unacceptable side effects including respiratory depression and addiction. A major goal for new pain therapeutics is to inhibit the sensory neurons which transmit pain signals (nociceptors) selectively without affecting other neurons involved in innocuous sensation or the central nervous system. However, nociceptor-specific therapeutic approaches remain in their infancy. Viral-based gene therapy offers several attractive advantages in treating refractory pain, as viruses can be engineered to deliver a wide range of molecules, can be administered locally or systemically, and have been recently approved by the Food and Drug Administration for a number of indications. However, nociceptor-specific viral tools do not presently exist in large part due to the extraordinary heterogeneity of sensory neurons that has made it difficult to identify molecular features that are unique to these cells. Recent advances in single-cell genomics have enabled us to generate a cell atlas that describes the genes that are selectively expressed in mouse and human nociceptors. This proposal aims to uncover the endogenous gene regulatory elements that mediate nociceptor-specific gene expression patterns and engineer these elements into barcoded adeno-associated viral libraries. To accomplish this, we propose the following specific aims: 1) Mapping nociceptor-specific gene regulatory elements in mouse and human and 2) Generation of a nociceptor-specific AAV toolkit. The nociceptor-specific viruses we develop in this proposal will be immediately useful to the scientific community for accessing nociceptors in wild-type mice and likely other species. In addition, because we will prioritize gene regulatory elements that are conserved between mouse and human nociceptors, we are optimistic that the viruses we screen in mice will also drive nociceptor-specific gene expression in humans. These next generation nociceptor-specific gene therapies would be ideally suited for treating certain refractory pain disorders because they can be administered locally to neuropathic sensory ganglia through standard outpatient procedures and can be engineered to drive expression of ion channels that silence nociceptor activity only in the presence of a specific drug (chemogenetics). This opioid-free approach could have significant translational applications for patients with refractory chronic pain who often have no other options for relief.