A gene and prgenitor cell therapy in Huntington disease mice

亨廷顿病小鼠的基因和祖细胞疗法

• 批准号: 8569489
• 负责人: ANTHONY WING SANG CHAN
• 金额: $ 19.52万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-01 至 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8569489
• 关键词: Alzheimer' s Disease; Amyotrophic Lateral Sclerosis; Atrophic; Behavior; Behavioral; Body Weights and Measures; Brain; CAG repeat; Cell Therapy; Cells; Cessation of life; Clinical assessments; Corpus striatum structure; Data; Effectiveness; Electrophysiology (science); Evaluation; Future; Gait abnormality; Genes; Genetic; Goals; Human; Huntington Disease; Impaired cognition; Implant; In Vitro; Involuntary Movements; Lead; Length; Longevity; Measures; Messenger RNA; MicroRNAs; Modeling; Monkeys; Movement; Mus; Neurodegenerative Disorders; Neuronal Differentiation; Neurons; Neurophysiology - biologic function; Nuclear Pore Complex; Parkinson Disease; Patients; Pattern; Phenotype; Population; Property; Proteins; RNA Interference; Replacement Therapy; Rodent Model; SCID Mice; Stem cells; Subfamily lentivirinae; Testing; Therapeutic; Transgenic Mice; Transgenic Organisms; Translations; Treatment Efficacy; Tremor; base; disease phenotype; functional restoration; gamma-Aminobutyric Acid; grasp; human Huntingtin protein; implantation; improved; in vivo; induced pluripotent stem cell; innovation; knock-down; mRNA Transcript Degradation; molecular pathology; mouse model; mutant; nerve stem cell; neuropathology; neurotoxicity; nonhuman primate; public health relevance; reconstitution; relating to nervous system; repaired; small hairpin RNA; success; tumor

DESCRIPTION (provided by applicant): Cell replacement therapy is a viable option as a long-term treatment for Huntington's disease (HD), where expansion of CAG repeats in Huntingtin (HTT) gene results in the degeneration of the majority of striatal neurons. The damaged neurons may be replaced by new functional neurons, which can be derived from induced pluripotent stem cells (iPSCs). However, iPSCs from the patients' cells harbor the same mutant HTT (mHTT) gene, which eventually will lead to toxic HTT protein accumulation and cell degeneration. Therefore, genetic repair should be done to reduce overproduction of mHTT proteins before cell replacement. Moreover, the integration of the replaced cells into the neuronal network is important for reconstituting neural functions. This study is evolved based on our recent success in developing a transgenic HD monkey model. HD monkeys develop cellular changes and neuropathologies similar to that of human patients, which are rarely observed in rodent models. Besides the neurotoxicity of mHTT in monkeys, HD monkeys also develop involuntary movement, difficulties in coordinating body movement, cognitive decline and striatal atrophy similar to that of HD patients. Our preliminary results show that iPSCs from our HD monkey can be in vitro differentiated into neural progenitor cells (NPCs) and GABAergic neurons, which form the majority of striatal neurons. We also show that NPCs grafted into severe combined immunodeficient (SCID) mice continue to differentiate into GABA expressing neurons after implantation and do not form tumors. These results suggest that NPCs derived from HD monkey/patients themselves may be utilized to replenish the population of the lost striatal neurons. However, it is unclear whether these NPCs will be able to restore the function of the striatum of HD. The overall objective of this proposal is to determine the effectiveness of NPCs replacement in rescuing the abnormal phenotype of HD mouse model. The proposed study will be used as a proof-of-principle which will lay the groundwork for future cell replacement therapy in HD monkeys by genetically correcting iPSC-derived NPCs from HD monkeys (rHD-NPCs). To achieve our goals, our approach is to suppress mHTT expression in rHD-NPCs with small hairpin RNA targeting the HTT gene (shRNA-htt) and then grafts the resulted rHD-NPCs into HD mice. Genetic modulation with shRNA can reduce the expression and subsequent accumulation of toxic mHTT, whereas cell replacement may improve the abnormal behavior and the atrophy of the striatum in HD mice model. To achieve our goals, we have two specific aims: (1) Determine neuronal differentiation properties of genetically modulated rHD-NPCs and (2) Determine the efficacy of rHD-NPC-siHD2 graft in rescuing the abnormal phenotype of HD mice.

描述（由申请人提供）：细胞替代疗法是亨廷顿病 (HD) 的长期治疗的可行选择，亨廷顿病 (HD) 中亨廷顿 (HTT) 基因中 CAG 重复的扩增会导致大多数纹状体神经元的退化。受损的神经元可能会被新的功能神经元取代，这些神经元可以源自诱导多能干细胞（iPSC）。然而，来自患者细胞的 iPSC 带有相同的突变 HTT (mHTT) 基因，最终将导致有毒的 HTT 蛋白积累和细胞变性。因此，在细胞替换之前应进行基因修复，以减少 mHTT 蛋白的过量产生。此外，被替换的细胞整合到神经元网络中对于重建神经功能很重要。这项研究是在我们最近成功开发转基因 HD 猴子模型的基础上发展而来的。 HD 猴子会出现与人类患者相似的细胞变化和神经病理学，这在啮齿动物模型中很少观察到。除了mHTT对猴子的神经毒性外，HD猴子还会出现与HD患者类似的不自主运动、身体运动协调困难、认知能力下降和纹状体萎缩。我们的初步结果表明，来自 HD 猴的 iPSC 可以在体外分化为神经祖细胞 (NPC) 和 GABA 能神经元，它们构成了纹状体神经元的大部分。我们还表明，移植到严重联合免疫缺陷（SCID）小鼠体内的 NPC 在植入后继续分化为表达 GABA 的神经元，并且不会形成肿瘤。这些结果表明，源自 HD 猴/患者本身的 NPC 可用于补充丢失的纹状体神经元的数量。然而，目前尚不清楚这些NPC是否能够恢复HD纹状体的功能。该提案的总体目标是确定 NPC 替代在挽救 HD 小鼠模型异常表型方面的有效性。拟议的研究将用作原理验证，通过对 HD 猴的 iPSC 衍生 NPC (rHD-NPC) 进行基因校正，为未来 HD 猴的细胞替代疗法奠定基础。为了实现我们的目标，我们的方法是用针对 HTT 基因的小发夹 RNA (shRNA-htt) 抑制 rHD-NPC 中 mHTT 的表达，然后将所得的 rHD-NPC 移植到 HD 小鼠中。 shRNA的基因调节可以减少有毒mHTT的表达和随后的积累，而细胞替代可以改善HD小鼠模型中的异常行为和纹状体萎缩。为了实现我们的目标，我们有两个具体目标：（1）确定基因调节的rHD-NPC的神经元分化特性；（2）确定rHD-NPC-siHD2移植物在挽救HD小鼠异常表型中的功效。