Gene therapy for Ataxia Telangiectasia

描述(申请人提供)：共济失调-毛细血管扩张症(A-T)是一种人类常染色体隐性遗传病，由编码蛋白质的基因突变引起，称为A-T突变(ATM)。A-T的特点是小脑性共济失调、视网膜毛细血管扩张、免疫缺陷、放射敏感性、不孕不育、易患恶性肿瘤和进行性神经元变性。A-T没有治愈的方法；因此，目前的治疗方法是缓解症状。在这里，我们建议通过HSV/AAV Rep+混合扩增载体来实现对A-T的靶向基因治疗。扩增载体中的转基因侧翼是腺相关病毒(AAV)反向末端重复序列(ITRs)，在AAV Rep蛋白存在的情况下，它可以在人类细胞和携带该人类序列的转基因小鼠细胞中实现高频率的整合到19号染色体上的AAVS1位点。在拟议的研究中，我们将评估A-T成纤维细胞和有丝分裂后ATM-/-神经元在基因组中的整合事件。我们还将在携带人AAVS1位点的ATM/小鼠模型中阐明体内特定部位的整合。HSV/AAV扩增载体将静脉注射到成年和新生ATM-/-AAVS1+/+小鼠体内，并注射到成年小鼠的小脑中，以评估神经细胞中的整合事件。这些研究的长期目标是探索治疗A-T的方法，该方法可转化为临床试验，并应适用于人类其他神经系统疾病。陈述：本建议重点是通过HSV/AAV杂交扩增载体实现对共济失调-毛细血管扩张(A-T)的靶向基因治疗。这些研究的长期目标是探索治疗A-T的方法，这些方法可以转化为临床试验，并应该适用于人类的其他神经疾病。

DESCRIPTION (provided by applicant): Ataxia-telangiectasia (A-T) is a human autosomal recessive disorder caused by mutations in the gene encoding a protein, termed A-T mutated (ATM). A-T is characterized by cerebellar ataxia, retinal telangiectasia, immunodeficiency, radiosensitivity, infertility, predisposition to malignancies and progressive neuronal degeneration. There is no cure for A-T; hence, current treatments are directed toward alleviating symptoms. Here we propose to achieve targeted gene therapy for A-T, mediated by an HSV/AAV Rep+ hybrid amplicon vector. The transgenes within the amplicon vectors are flanked with adeno-associated virus (AAV) inverted terminal repeats (ITRs) sequences, which in the presence of AAV Rep proteins can achieve a high frequency of integration into the AAVS1 site on chromosome 19 in human cells and in transgenic mouse cells bearing this human sequence. In the proposed studies, we will evaluate integration events into the genome of dividing A-T fibroblasts and post mitotic Atm -/- neurons. We will also elucidate site-specific integration in vivo, in an Atm -/- mouse model bearing human AAVS1 sites. The HSV/AAV amplicon vectors will be injected intravenously into adult and neonatal Atm -/- AAVS1 +/+ mice, and into the cerebellum of adult mice to evaluate integration events in neural cells. The long-term goal of these studies is to explore means of therapy for A-T, which could be translated into clinical trials and should be applicable to other neurologic diseases in humans.Narrative: This proposal focuses on achieving targeted gene therapy for ataxia-telangiectasia (A-T) mediated by an HSV/AAV hybrid amplicon vector. The long-term goal of these studies is to explore means of therapy for A-T, which could be translated into clinical trials and should be applicable to other neurologic diseases in humans.