Novel viral tools for control of bladder function and pain

 描述(申请人提供)：有许多影响膀胱的疾病没有得到足够的治疗。例如，间质性膀胱炎(IC)和膀胱过度活动症(OAB)是以排尿频率和紧迫感增加为特征的慢性泌尿系统疾病；IC与OAB的不同之处在于，患者还会遭受盆腔/耻骨上疼痛。同样，无法排空膀胱是脊髓损伤患者中常见的衰弱问题(通常与剧烈疼痛有关)，对一些患者来说，是导致生活质量下降的主要原因。在所有这些例子中，它并不完全是 明确不同的膀胱传入亚群是如何不同地驱动这些症状的，因此，在探索基于机制的方法之前，需要解决一些基础科学问题。我们的实验室(戴维斯实验室)一直在使用在感觉神经元中表达通道视紫红质(ChR2)或卤视紫质(NpHR)的遗传小鼠品系。本申请中提供的初步数据表明，这些光敏通道可用于调节内脏运动反射(膀胱疼痛的替代物)以及控制排尿反射。不幸的是，我们之前的研究依赖于转基因小鼠模型，这种模型具有遗传技术固有的显著局限性，这种基因技术产生在胚胎发生期间被激活的永久性基因变化，并且缺乏时间和空间控制。需要新的工具来确定我们的观察是否可以扩展到其他相关的动物模型，以及开发成对人类的有效治疗。本申请是对RFA-RM-15-002号文件的响应，RFA-RM-15-002致力于开发“为研究中的具体用例/机制量身定做”的工具，其“最终交付成果是一种工具或技术，而不是生物发现”(来自向潜在申请者提供的共同基金pdf)。这项应用的合作伙伴(Glorioso博士)是使用感觉神经元特异性病毒的先驱，这种病毒可以 被用来激活或沉默感觉神经元。特别是，他开发了一种新的、可药物的氯离子通道(伊维菌素)结构，可以有效地阻断躯体疼痛。此外，Glorioso实验室还生产了其他通过第一阶段人体试验的新型病毒构建物，使拟议的研究能够满足本RFA所要求的可译性标准。这一“概念证明”数据虽然令人兴奋，但只有在开发出适当的策略允许这些分子在人类体内表达的情况下，才适用于人类膀胱(以及其他动物模型)。拟议中的研究计划将结合这两个实验室的努力；一个研究疼痛和内脏器官功能的调节，另一个在设计感觉神经元特异性病毒方面有着长期的记录，这些病毒可以用于靶向初级传入的新基因的表达。我们将生产和测试9种不同的病毒构建体(在三种不同的启动子下表达三种新基因)，针对不同的感觉神经元群体，并确定它们对控制排尿和内脏运动反射(膀胱疼痛的替代品)的有效性。

 DESCRIPTION (provided by applicant): There are a number of diseases that affect the bladder that do not have adequate treatments. For example, interstitial cystitis (IC) and overactive active bladder (OAB) are chronic urological disorders characterized by increased micturition frequency and urgency; IC is distinct from OAB in that patients additionally suffer from pelvic/suprapubic pain. Likewise, inability to empty the bladder is a common debilitating problem (often associated with severe pain) among spinal cord injury patients and for some, is the major contributor to decreased quality of life. In all of these examples, it is not completely clear how distinct subpopulations of bladder afferents differentially drive these symptoms and thus, there are basic science issues that need to be addressed before mechanism-based approaches can be explored. Our laboratory (the Davis lab) has been using genetic mouse lines that express channelrhodopsin (ChR2) or halorhodopsin (NpHR) in sensory neurons. Preliminary data presented in this application demonstrate that these light sensitive channels can be used to regulate the visceromotor reflex (a surrogate for bladder pain) as well as control the micturition reflex. Unfortunately, our previous studies rely on transgenic mouse models that have significant limitations inherent in a genetic technology that produces permanent gene changes that are activated during embyogenesis and lack temporal and spatial control. New tools are needed to determine if our observations can be extended to other relevant animal models, as well as developed into effective treatments for human. This application is in response to RFA-RM-15-002 that strives to develop tools that will "be tailored to the specific use case/mechanism under study" and whose "end deliverable is a tool or technology, NOT a biological discovery" (from Common Fund pdf provided to potential applicants). The co-PI on this application (Dr. Glorioso) is a pioneer in the use of sensory neuron-specific viruses that can be used to activate or silence sensory neurons. In particular, he has developed a novel, druggable chloride channel (ivermectin) construct that is effective in blocking somatic pain. In addition, the Glorioso lab has produced other novel viral constructs that have passed phase I human trials, allowing the proposed studies to meet the criteria of translatability that is require by this RFA. This "proof of concept" data while exciting, will only be applicable to human bladder (as well as other animal models) if appropriate strategies are developed that will allow expression of these molecules in humans. The proposed research program will combine the efforts of these two laboratories; one studying pain and regulation of visceral organ function and a second that has a long track-record in designing sensory neuron-specific viruses that can be used to target expression of novel genes to primary afferents. We will produce and test 9 different viral constructs (expressing three novel genes, under three different promoters), targeted to different sensory neuron populations and determine their effectiveness for control micturition and the visceromotor reflex (a surrogate for bladder pain).