Intravenous MitoTargeted AAV9 Gene Therapy for Treatment of Visual Loss and Encephalopathy in Leigh Syndrome and NARP

线粒体DNA突变会导致一系列神经退行性疾病，对这些疾病来说， 有效的治疗方法是存在的。这是一组无法治愈的疾病，影响着眼睛，紧张 系统和心脏，其中一些在一个世纪前具有临床特征，但现在已知 是一系列分子定义的疾病。我们选择了从世界上最大的 严重的，线粒体DNA ATP6突变(T8993G)与母体相关 遗传性Leigh综合征(MILS)，一种以导致失明和 儿童早期的快速致命性脑脊髓病或神经源性共济失调和视网膜炎 成年期早期的色素性。 我们在确定疾病的发病机制和测试治疗方法方面取得了重大进展。 另一种常见的线粒体疾病是Leber遗传性视神经病变(LHON)。在这 我们建议设计、修改和测试一种临床相关的疗效和安全性 ATP6基因突变所致MILS和NARP的载体治疗我们的目标是：(1) 通过开发MTS AAV 9型载体促进MILS和NARP的翻译研究 用于静脉注射将正常的ATP6基因直接输送到线粒体并进行测试 100%突变的T8993G线粒体DNA在线虫细胞中的表达以挽救呼吸。 (2)评价MTS AAV9载体静脉注射对正常小鼠的生物学效应 这导致了线粒体基因转移而没有不良影响。(3)为了挽救视力丧失， 转基因ATP6小鼠的脑脊髓病和死亡。我们希望找出这些条件 用于长期挽救小鼠的视力丧失和脑脊髓病，使这种方法可以 在I/II期临床中进行测试，旨在恢复MILS和 纳普病患者。

Mutations in mitochondrial DNA lead to a spectrum of neurodegenerative diseases for which no effective treatment exists. This is a group of untreatable disorders affecting the eye, nervous system and heart, some clinically characterized over a century ago, but they are now known to be a spectrum of molecularly defined diseases. We had chosen to start with one of the most severe, the ATP6 mutation (T8993G) in mitochondrial (mt) DNA responsible for Maternally Inherited Leigh Syndrome (MILS), a neurologic disease renowned for causing blindness and rapidly fatal encephalomyelopathy in early childhood or Neurogenic Ataxia and Retinitis Pigmentosa in early adulthood. We have made major strides towards determining the pathogenesis and testing treatments for another common mitochondrial disorder Leber hereditary optic neuropathy (LHON). In this application, we propose to design, modify and test the efficacy and safety of a clinically relevant vector for the treatment of MILS and NARP caused by mutated ATP6. Our Aims are: (1) To facilitate translational studies for MILS and NARP by developing an MTS AAV serotype 9 vector for intravenous use to deliver the normal ATP6 gene directly to the mitochondria and test expression to rescue respiration in cybrid cells with 100% mutated T8993G mitochondrial DNA. (2) To evaluate biological effects of intravenous delivery of MTS AAV9 vectors in normal mice that result in mitochondrial gene transfer without adverse effects.(3) To rescue visual loss, encephalomyelopathy and death in transgenic ATP6 mice. We hope to identify the conditions for long-term rescue of visual loss and encephalomyelopathy in mice, so that this approach can be tested in a phase I/II clinical designed to restore visual and neurologic function in MILS and NARP patients.