Atheroprotective Gene Therapy

项目总结 动脉粥样硬化是一种血管壁疾病，会导致心脏病发作和中风。尽管有重大的 在内科和外科治疗的进步中，动脉粥样硬化仍然会导致显著的发病率和死亡率。 例如，大幅降低低密度脂蛋白胆固醇(降至~30 mg/dL)的药物治疗只会略微减少 不良心血管事件和死亡率。除了降低低密度脂蛋白，还需要新的方法。宽阔的， 该项目的长期目标是开发一种通过以下途径预防和逆转动脉硬化的疗法 针对血管壁的干预措施。这种新的疗法涉及到引入和表达 排列在血管壁上的细胞中的疾病预防基因，因此被称为“动脉粥样硬化保护” 基因疗法。“用这种基因疗法治疗的血管不会发生动脉粥样硬化，因为它们 通过基因改造来抵抗导致动脉粥样硬化的潜在生物过程：积聚 胆固醇和炎症细胞以及血管细胞炎症通路的激活。这个项目是 专注于防止胆固醇在血管中积聚(和相关炎症)的基因治疗 墙壁。血管壁靶向基因治疗特别适用于预防静脉粥样硬化 用于冠状动脉搭桥术。静脉移植物动脉粥样硬化进展迅速，导致移植物狭窄 和闭塞，并且没有得到适当的治疗。我们的方法最终可以消除静脉移植物动脉粥样硬化。 有三个特定的目的，都是在兔身上实现的。目标集中于临床发展。 有用的动脉粥样硬化保护基因治疗--由一种有前途的基因转移载体--“助手依赖”提供 腺病毒“(Adenovus)。HDAd是一种有吸引力的人类基因治疗载体，因为它表达了治疗性的 基因在动物(包括非人类灵长类动物)中稳定存在多年，并且相对不具炎症性。三人组 具体目标是开发HDAd的前景，并采取下一步关键步骤来开发基因疗法 预防和逆转动脉粥样硬化：Aim 1将测试HDAD介导的 载脂蛋白A-I(apoA-I)或三磷酸腺苷结合盒A亚家族成员1(ABCA1)可预防 移植兔静脉中的动脉粥样硬化。AIM 2将开发新型表达盒，实现高水平， 在体内的内皮细胞中稳定的、细胞特异性的转基因表达。目标3将通过以下方式确定这些机制 哪种从内皮细胞产生载脂蛋白A-I的动脉粥样硬化保护基因疗法可以预防动脉粥样硬化。 这三个目标的实现将使临床血管基因治疗通过测试2更接近实施 在大型动物模型中有希望的治疗基因(目标1)。这些目标的实现也可能产生小说 可用于在内皮细胞中高水平表达转基因的载体平台，还可以 深入了解内皮细胞基因转录的机制(目标2)。身份识别 载脂蛋白A-I血管基因治疗预防动脉粥样硬化的机制(目标3)将提示 改进载脂蛋白A-I血管基因治疗和开发辅助基因治疗的方法。

PROJECT SUMMARY Atherosclerosis is a disease of the blood vessel wall that causes heart attacks and strokes. Despite major advances in medical and surgical management, atherosclerosis still causes significant morbidity and mortality. For example, drug therapy that dramatically lowers LDL-cholesterol (to ~30 mg/dL) only marginally decreases adverse cardiovascular events and mortality. New approaches, beyond LDL lowering, are needed. The broad, long-term objective of this project is to develop a therapy that prevents and reverses atherosclerosis via interventions targeted at the blood vessel wall. This novel therapy involves the introduction and expression of disease-preventing genes in the cells that line blood vessel walls and is accordingly termed “atheroprotective gene therapy.” Blood vessels treated with this gene therapy would not develop atherosclerosis because they are genetically modified to resist the underlying biological processes that cause atherosclerosis: accumulation of cholesterol and inflammatory cells and activation of vascular cell inflammatory pathways. This project is focused on gene therapy that prevents cholesterol accumulation (and associated inflammation) in blood vessel walls. Vessel wall-targeted gene therapy is particularly well suited for prevention of atherosclerosis in veins used for coronary artery bypass grafts. Vein-graft atherosclerosis progresses rapidly, leads to graft narrowing and occlusion, and is inadequately treated. Our approach could eventually eliminate vein-graft atherosclerosis. There are 3 specific aims, all of which are carried out in rabbits. The aims are focused on developing clinically useful atheroprotective gene therapy, delivered by a promising gene-transfer vector, “helper-dependent adenovirus” (HDAd). HDAd is an attractive vector for human gene therapy because it expresses therapeutic genes stably for years in animals (including nonhuman primates) and is relatively non-inflammatory. The 3 specific aims exploit the promise of HDAd and take the next critical steps towards developing gene therapy that prevents and reverses atherosclerosis: Aim 1 will test whether HDAd-mediated expression of apolipoprotein A-I (apoA-I) or ATP-binding cassette subfamily A, member 1 (ABCA1) can prevent atherosclerosis in grafted rabbit veins. Aim 2 will develop novel expression cassettes that achieve high-level, stable, cell-specific transgene expression in endothelium in vivo. Aim 3 will identify the mechanisms through which atheroprotective gene therapy that produces apoA-I from endothelial cells prevents atherosclerosis. Accomplishment of the 3 aims will bring clinical vascular gene therapy closer to implementation by testing 2 promising therapeutic genes in a large animal model (Aim 1). Accomplishment of the aims may also yield novel vector platforms that are useful for expressing transgenes at high levels in endothelial cells and may also provide insights into mechanisms of endothelial cell gene transcription (Aim 2). Identification of the mechanisms through which apoA-I vascular gene therapy prevents atherosclerosis (Aim 3) will suggest approaches for improving apoA-I vascular gene therapy and for the development of adjunctive gene therapies.