AAV-mediated gene therapy for CNS disease correction in feline NPC1 disease

项目概要/摘要 C1 型尼曼-匹克病（NPC1 病）是一种以溶酶体贮积为特征的遗传性疾病 胆固醇和鞘脂的含量，以及进行性小脑共济失调、痴呆、垂直 核上性凝视麻痹、吞咽困难和早逝。目前尚无 FDA 批准的 NPC1 疗法 疾病。在小脑池内 (IC) 重复施用 2-羟丙基-β-环糊精 (HPßCD) 患有 NPC1 疾病的猫可以预防小脑共济失调的发生，预防浦肯野细胞死亡，使其正常化 小脑皮质和脑皮质胆固醇和神经节苷脂浓度，并增加生存时间。 这些临床前数据将 IC HPßCD 推进到临床试验中，并已证明其功效。 然而，在患者一生中，HPßCD 必须每两周注射一次 IC，这会导致 进行性剂量限制性耳毒性，突出表明明确需要针对这些疾病的侵入性更小且更安全的治疗方法 患者。 我们假设使用 AAV9 载体将 NPC1 递送至大脑来优化 IC 基因治疗将 有效预防NPC1疾病相关的小脑共济失调和浦肯野细胞病理，无需重复 终身注射且无耳毒性。我们还假设颈动脉内（IV）施用一种新型 猫的 AAV 血清型可以将 NPC1 递送至未接受 IC 治疗的基底神经节和脑干区域 HPßCD 或 AAV9 的管理，并负责肌张力障碍、垂直核上性凝视麻痹和 吞咽困难。因此，在拟议的研究中，我们将评估优化 AAV9 介导的方法 转导最大数量的浦肯野细胞（目标 1），评估 AAV9-NPC1 的功效 给药治疗 NPC1 相关小脑疾病的临床、生化和组织学方面（目标 2），评估颈动脉内AAV-NPC1给药治疗小脑外区域的疗效 导致痴呆（大脑皮层）、肌张力障碍（基底神经节）和垂直核上性凝视麻痹 吞咽困难（脑干）（目标 3）。 这些概念验证研究将是第一个优化非扩散膜结合的递送的研究 蛋白转化为浦肯野细胞，从而推进针对影响浦肯野细胞的许多其他遗传疾病的基因治疗 细胞，包括脊髓小脑共济失调。此外，这些研究将是第一个开发一次性疗法的研究 用于治疗 NPC1 疾病，可治疗小脑和小脑外疾病，并且不会产生耳毒性。

Project Summary/Abstract Niemann-Pick disease type C1 (NPC1 disease) is a hereditary disorder characterized by the lysosomal storage of cholesterol and sphingolipids, and clinical signs of progressive cerebellar ataxia, dementia, vertical supranuclear gaze palsy, dysphagia, and early death. There are no FDA-approved therapies for NPC1 disease. Repeated intracisterna magna (IC) administration of 2-hydroxypropyl-beta-cyclodextrin (HPßCD) in cats with NPC1 disease prevented the onset of cerebellar ataxia, prevented Purkinje cell death, normalized cerebellocortical and cerebrocortical cholesterol and gangliosides concentrations, and increased survival time. These preclinical data advanced IC HPßCD into clinical trials where efficacy has been demonstrated. However, HPßCD must be administered IC every two weeks for the duration of the patient’s life and results in progressive dose-limiting ototoxicity, highlighting a clear need for less invasive and safer therapies for these patients. We hypothesize that optimization of IC gene therapy using an AAV9 vector to deliver NPC1 to the brain will effectively prevent NPC1 disease-associated cerebellar ataxia and Purkinje cell pathology without repeated lifelong injections and without ototoxicity. We also hypothesize that intracarotid (IV) administration of a novel AAV serotype to cats can deliver NPC1 to the basal ganglia and brainstem, regions which are untreated by IC administration of HPßCD or AAV9, and are responsible for dystonia, vertical supranuclear gaze palsy, and dysphagia. Therefore, in the proposed studies we will assess methods to optimize AAV9-mediated transduction of the greatest number of Purkinje cells (Aim 1), evaluate the efficacy of AAV9-NPC1 administration to treat clinical, biochemical, and histologic aspects of NPC1-associated cerebellar disease (Aim 2), and evaluate the efficacy of intracarotid AAV-NPC1 administration to treat extracerebellar regions responsible for dementia (cerebral cortex), dystonia (basal ganglia), and vertical supranuclear gaze palsy and dysphagia (brainstem) (Aim 3). These proof-of-concept studies will be the first to optimize the delivery of a non-diffusible membrane-bound protein to Purkinje cells, thereby advancing gene therapy for many other genetic diseases affecting Purkinje cells including spinocerebellar ataxias. Moreover, these studies will be the first to develop a one-time therapy for NPC1 disease that treats both cerebellar and extracerebellar disease and results in no ototoxicity.