Leber Hereditary Optic Neuropathy: Gene Therapy Trial

莱伯遗传性视神经病：基因治疗试验

• 批准号: 7936872
• 负责人: John Guy
• 金额: $ 86.25万
• 依托单位: UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-05-01 至 2013-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7936872
• 关键词: ATP Synthesis Pathway; Affect; Amino Acids; Animal Model; Antibodies; Apoptosis; Arginine; Axon; Behavior; Biodistribution; Biological; Biological Assay; Blindness; Cells; Childhood; Clinical; Clinical Protocols; Clinical Trials; Clinical Trials Design; Codon Nucleotides; Collaborations; Complex; Consensus; Cultured Cells; DNA; Data; Development; Disease; Dose; Effectiveness; Feedback; Funding; Gene Delivery; Genes; Goals; Grant; Hearing; Heart; Histidine; Human; Individual; Injection of therapeutic agent; Investigational Drugs; Investigational New Drug Application; Knowledge; Leber' s Hereditary Optic Neuropathy; Mediating; Mitochondria; Mitochondrial DNA; Mitochondrial Diseases; Monoclonal Antibody R24; Mus; Mutate; Mutation; Nature; Neuro-Ocular System; Nuclear; Optic Disk; Optic Nerve; Outcome; Outcome Measure; Oxidative Phosphorylation; Pathogenesis; Patients; Persons; Phase; Preclinical Testing; Primates; Principal Investigator; Production; Proteins; Reactive Oxygen Species; Reading Frames; Recombinants; Recovery; Relative (related person); Research; Research Personnel; Respiratory physiology; Retina; Safety; Schedule; Series; Simplexvirus; Site-Directed Mutagenesis; Swelling; Techniques; Technology; Testing; TimeLine; Toxic effect; Toxicology; United States National Institutes of Health; Validation; Vision; Visual system structure; Work; adeno-associated viral vector; design; emerging adult; ganglion cell; gene complementation; gene therapy; human disease; in vivo; man; meetings; mutant; optic nerve disorder; organizational structure; preclinical study; preclinical toxicity; prevent; programs; research clinical testing; symposium; therapeutic evaluation; vector

DESCRIPTION (provided by applicant): Our understanding of human diseases caused by mutated mitochondrial DNA has recently evolved dramatically. This is a group of untreatable disorders affecting the eye, nervous system and heart, some that have been clinically characterized over a century ago, but they are now known to be a spectrum of molecularly defined diseases. We have chosen to start with one of the most severe, the G11778A mutation in mitochondrial DNA responsible for Leber Hereditary Optic Neuropathy (LHON) a disease group renowned for causing blindness in later childhood and early adulthood. It shows little or no propensity for recovery. In previous work we have made major strides towards determining the pathogenesis and testing a treatment for LHON. First, we discovered that ND4 mutant cells have a severe reduction in ATP synthesis, even though mild reductions in complex I activity appear insufficient to induce disease. Since no technology existed to introduce DNA directly into mitochondria, we overcame this deficiency in oxidative phosphorylation by constructing a "nuclear version" of the mitochondrial gene then targeted the cytoplasmically synthesized protein to the mitochondria by using a targeting sequence appended to the reading frame (allotopic expression). When delivered to cultured cells containing a mutant ND4, respiratory function was restored. Next, we created a bona fide animal model for LHON. Using site directed mutagenesis of the nuclear version of ND4 we replaced the codon for arginine to that for histidine at amino acid 340. Injection of this construct into the mouse visual system disrupted mitochondrial cytoarchitecture, elevated reactive oxygen species, induced swelling of the optic nerve head and induced apoptosis, with a progressive demise of ganglion cells in the retina and their axons comprising the optic nerve. In contrast, ocular expression of the wild-type human ND4 subunit appeared safe, suggesting that it may be useful for treatment of patients with LHON. Here by using the scientific and clinical knowledge acquired to date we will begin the journey towards genetic therapy for human optic neuropathy and mitochondrial disease. Our goal in this application is to test the relevance of allotopic rescue of our LHON animal model; the safety of AAV mediated delivery of the ND4 gene and the effectiveness of this therapy in preventing and restoring visual loss in our patients with LHON.

描述（由申请人提供）：我们对由线粒体DNA突变引起的人类疾病的理解最近发生了巨大的变化。这是一组影响眼睛、神经系统和心脏的无法治愈的疾病，其中一些在一个多世纪前就被临床描述了，但现在人们知道它们是一系列分子定义的疾病。我们选择从最严重的一种开始，线粒体DNA中的G11778A突变导致Leber遗传性视神经病变（LHON），这是一种以导致儿童晚期和成年早期失明而闻名的疾病。它显示出很少或根本没有恢复的倾向。在以前的工作中，我们在确定LHON的发病机制和测试治疗方法方面取得了重大进展。首先，我们发现ND4突变细胞的ATP合成严重减少，尽管复合物I活性的轻微减少似乎不足以诱导疾病。由于不存在将DNA直接引入线粒体的技术，我们通过构建线粒体基因的“核版本”来克服氧化磷酸化的缺陷，然后通过附加在阅读框上的靶向序列（异位表达）将细胞质合成的蛋白质靶向到线粒体。当传递到含有ND4突变体的培养细胞时，呼吸功能恢复。接下来，我们为LHON创建了一个真正的动物模型。利用ND4核版本的定点诱变，我们将340个氨基酸上的精氨酸密码子替换为组氨酸密码子。将这种结构物注射到小鼠视觉系统中，会破坏线粒体细胞结构，提高活性氧含量，诱导视神经头肿胀并诱导细胞凋亡，导致视网膜神经节细胞及其轴突组成视神经的细胞逐渐死亡。相比之下，野生型人ND4亚基的眼部表达似乎是安全的，这表明它可能对LHON患者的治疗有用。在这里，利用迄今为止获得的科学和临床知识，我们将开始人类视神经病变和线粒体疾病的基因治疗之旅。我们在这个应用程序中的目标是测试我们的LHON动物模型的异体抢救的相关性；AAV介导的ND4基因递送的安全性以及该疗法在预防和恢复LHON患者视力丧失中的有效性。