Regulated Transgene Expression in the Retina

描述（由申请人提供）：本申请解决了基因组学的广泛挑战领域（区域 08），具体的挑战主题是 08-EY-101：复杂眼病的基因组学。 影响视力的疾病已成为基因治疗的潜在候选者。 将病毒载体（例如基于腺相关病毒（AAV）的病毒载体）直接注射到眼睛的不同区室中，可导致基因转移和稳定的转基因表达到各种细胞类型中。 视网膜下注射AAV载体后，可以实现视网膜色素上皮细胞和光感受器的高水平转导；这种方法已被用于治疗动物模型和人类中一种称为莱伯先天性黑蒙的先天性失明。许多其他形式的获得性和遗传性失明是基因治疗的潜在候选者，尽管在许多情况下需要调节转基因的表达以确保治疗性表达而无毒性。该提案将开发一种在引入视网膜后对 AAV 编码基因进行药理学调节的方法，用于治疗湿性年龄相关性黄斑变性 (AMD)。该方法基于在诱导型启动子的控制下引入编码血管内皮生长因子（VEGF）抗体的基因以及编码工程化转录因子的基因，该转录因子可以被小分子激活以特异性增强转基因的表达。 这种称为 ARGENT 的诱导转基因表达方法将使用方便的报告基因在小鼠和猴子的视网膜中开发。 将在 AMD 小鼠模型中使用编码名为 Avastin 的人源化 VEGF 抗体的载体进行研究；这些载体还将在猴子身上进行安全性和药代动力学测试。针对 AMD 的 ARGENT 系统的开发将提供一个可应用于广泛的视网膜疾病的基因治疗平台。 该申请的资助将创造 2 个新就业岗位。 已根据预算理由中的描述确定了这些职位的候选人。 公共健康相关性：年龄相关性黄斑变性 (AMD) 是一种日益严重的疾病：1995 年有 170 万人患上 AMD，预计到 2030 年将有 630 万人受到影响。这种疾病是 60 岁以上人群视力障碍的主要原因，随着预期寿命的延长，它不仅是一个医疗问题，而且会产生重大的社会经济影响。该提案旨在开发一种基因疗法，为患者提供显着的医疗缓解，开发适用于其他眼科适应症的技术，并最大限度地减少治疗干预和医疗保健系统的负担。

DESCRIPTION (provided by applicant): This application addresses the broad Challenge Area of Genomics (area 08) and the specific Challenge Topic is 08-EY-101: Genomics of complex eye diseases. Diseases that affect visual acuity have emerged as potential candidates for gene therapy. Direct injection of viral vectors, such as those based on adeno- associated viruses (AAV), into different compartments of the eye leads to gene transfer and stable transgene expression into various cell types. High level transduction of retinal pigmented epithelial cells and photoreceptors can be achieved following sub-retinal injection of AAV vectors; this approach has been used to treat a congenital form of blindness called Leber congenital amaurosis in animal models and humans. Many other forms of acquired and inherited blindness are potential candidates for gene therapy although in many cases it will be necessary to regulate expression of the transgene so as to assure therapeutic expression without toxicity. This proposal will develop a method for pharmacologically regulating AAV-encoded genes after introduction into the retina for the treatment of the wet form of age-related macular degeneration (AMD). The method is based on the introduction of a gene encoding an antibody to vascular endothelial growth factor (VEGF) under the control of an inducible promoter together with genes encoding an engineered transcription factor that can be activated by a small molecule to specifically enhance expression of the transgene. This method of inducible transgene expression called ARGENT will be developed in retina of mice and monkeys using convenient reporter genes. Studies will be performed with vectors encoding the humanized VEGF antibody called Avastin in mouse models of AMD; these vectors will also be tested in monkeys for safety and pharmacokinetics. Development of the ARGENT system for AMD will provide a platform of gene therapy that can be applied to a broad array of retinal diseases. Funding of this application will create 2 new jobs. Candidates have been identified for these positions as described in the Budget Justification. PUBLIC HEALTH RELEVANCE: Age-related macular degeneration (AMD) is a growing disease: 1.7 million people developed AMD in 1995 while it is projected that 6.3 million will be affected in 2030. The disease is a major cause for visual disability among persons over 60 years of age that with the increase in life expectancy is not only a medical problem but also one with a significant socio-economic impact. This proposal is designed to develop a gene therapeutic that will provide significant medical relief to patients, develop technologies applicable to other indications in the eye and minimize therapeutic interventions and the burden on the healthcare system.