Targeted Therapy for Pompe Disease

7.项目摘要/摘要 庞培病是一种致命的神经肌肉疾病，由编码酸性的基因突变引起。 α-葡萄糖苷酶--溶酶体糖原水解所必需的一种酶。换气不足与呼吸 功能不全是庞贝病的显著特征，会导致未经治疗的婴儿呼吸衰竭。 尽管呼吸问题传统上被归因于呼吸肌和运动神经元 病理学，我们最近描述了平滑肌(SM)病理在呼吸道- 这种疾病的相关发病率。目前，FDA批准的唯一可用于庞贝患者的治疗方法是 酶替代疗法(ERT)。ERT显著提高了存活率，但随着患者寿命的延长， 危险的SM病理，如血管动脉瘤破裂和呼吸道无力，已被揭开面纱。 ERT后残留的SM受累和细胞功能障碍的程度仍不清楚，将是一个 这个项目的重点。此外，我们还将研究腺相关病毒(AAV)基因治疗的疗效。 治疗庞贝SM受累。AAV基因治疗是庞贝病等单基因疾病的理想选择， 然而，有证据表明，针对SM、骨骼、心脏和运动神经元的婴儿庞贝病AAV 仍然是缺乏的。我们提出了一系列直接针对SM溶酶体糖原的临床前实验 Pompe病的蓄积和探索AAV载体靶向所有受影响肌肉群的有效性 和运动神经元。我们将重点研究针对SM溶酶体糖原的AAV血清型和启动子 Pompe病的积聚以及心脏、骨骼和运动神经元的病理。总体而言， 支持这一提议的基本假设是广泛的平滑肌糖原积聚 尽管有ERT，Pompe病仍持续存在，需要一种新的AAV载体来治疗平滑、 骨骼、心脏和运动神经元病理学。我们的假设是基于初步的 Pompe病小鼠模型中的数据以及在我们的Pompe病患者中看到的临床证据。三 将使用已建立的庞贝病小鼠模型来实现特定目标：目标1： 全面检查庞贝病的呼吸道和血管SM受累情况及其影响 自噬失调的病理学。目的2：比较早期和晚期ERT对呼吸和血管SM的影响 功能和糖原蓄积。目的3：检测一种设计合理的新型AAV8g9-GAA的性能 比较有效地转导和清除SM、骨骼肌和运动神经元糖原积聚 AAV8和AAV9。该项目将解决关于平滑肌功能障碍的知识差距，并将 确定一种治疗婴儿庞贝病的新型AAV疗法的潜力，以显著降低发病率和 死亡率。

7. PROJECT SUMMARY/ABSTRACT Pompe disease is a fatal neuromuscular disorder that results from mutations in the gene encoding acid α-glucosidase (GAA) - an enzyme necessary for lysosomal glycogen hydrolysis. Hypoventilation and respiratory insufficiency are prominent features of Pompe disease that result in respiratory failure in untreated infants. Although breathing problems have traditionally been attributed to respiratory muscle and motor neuron pathology, we recently described the significant role of smooth muscle (SM) pathology in the respiratory- related morbidity of this disease. Currently, the only FDA approved therapy available to Pompe patients is enzyme replacement therapy (ERT). ERT has significantly increased survival but as patients live longer, life threatening SM pathology such as ruptured vascular aneurysms and airway weakness, has been unmasked. The extent of residual SM involvement and cellular dysfunction following ERT remains unknown and will be a focus of this project. In addition, we will study the efficacy of adeno-associated viral (AAV) gene therapy in treating Pompe SM involvement. AAV gene therapy is ideal for monogenetic disorders such as Pompe disease, however evidence of an AAV for infantile Pompe disease that targets SM, skeletal, cardiac and motor neurons is still lacking. We propose a series of pre-clinical experiments that directly address SM lysosomal glycogen accumulation in Pompe disease and explore the efficacy of AAV vectors in targeting all affected muscle groups and motor neurons. We will focus on an AAV serotype and promoter that targets SM lysosomal glycogen accumulation as well as cardiac, skeletal and motor neuron pathology in Pompe disease. Overall, the fundamental hypothesis driving this proposal is that extensive smooth muscle glycogen accumulation persists in Pompe disease despite ERT and that a novel AAV vector is necessary to treat smooth, skeletal, cardiac, and motor neuron pathology. Our hypothesis has been formulated based on preliminary data in the Pompe disease mouse model as well as clinical evidence seen in our Pompe disease patients. Three specific aims will be accomplished using an established mouse model of Pompe disease: Aim 1: To comprehensively examine respiratory and vascular SM involvement in Pompe disease and the impact of this pathology on autophagic dysregulation. Aim 2: To compare early and late ERT on respiratory and vascular SM function and glycogen accumulation. Aim 3: To examine the ability of a novel rationally designed AAV8g9-GAA to effectively transduce and clear SM, skeletal muscle, and motor neuron glycogen accumulation in comparison to AAV8 and AAV9. This project will address a gap in knowledge regarding smooth muscle dysfunction and will identify the potential of a novel AAV therapy for infantile Pompe disease to significantly reduce morbidity and mortality.