Project 1: Preclinical development of surrogate gene therapy using GALGT2

摘要 项目1将专注于扩大GALGT2基因治疗的临床用途 RAAVrh74.MCK.GALGT2.RAAVRh74.MCK.GALGT2是一种替代基因疗法， 刺激骨骼和心脏组织中人GALGT2基因的过度表达 肌肉。这种载体刺激改变了的肌膜糖基化， 包括α营养不良多糖的糖基化，使其正常模拟糖基化 发现于神经肌肉和肌腱连接处，并增加了 抗肌营养不良蛋白和层粘连蛋白α2替代物的突触外表达 抑制肌营养不良症。临床前研究表明，肌肉GALGT2 过表达抑制Duchenne肌营养不良症小鼠模型的疾病 先天性肌营养不良症(DMD)、先天性肌营养不良症(CMD1A)和肢体肌营养不良 营养不良2D(LGMD2D)。该载体利用了aav血清型，rh 74，表现出很好的 通过载体传递基因到肌肉中的效果 而MCK启动子将基因表达限制在肌肉细胞中。广泛性 概念验证和安全性研究已导致IND用于 DMD患者rAAVRH74.MCK.GALGT2当这些临床试验开始的时候， 我们希望在这里进行概念验证研究，以允许扩大使用 CMD1A和LGMD2D患者携带rAAVrh74.MCK.GALGT2。进一步的研究是 目的扩大rAAVrh74、MCK.GALGT2基因治疗在DMD中的应用 通过研究这种基因疗法是否可以增加对患者的治疗 外显子跳跃治疗或基因过表达治疗的疗效 卵泡抑素，一种肌肉抑制素，可以形成新的肌肉块。所有的实验 在这里提出的是针对快速翻译的新的治疗方法 肌肉营养不良，这是CORT提案的首要目标。

ABSTRACT Project 1 will focus on expanding the clinical usefulness of GALGT2 gene therapy using rAAVrh74.MCK.GALGT2. rAAVrh74.MCK.GALGT2 is a surrogate gene therapy that stimulates the overexpression of the human GALGT2 gene in skeletal and cardiac muscle. This vector stimulates changed glycosylation of the muscle membrane, including glycosylation of α dystroglycan, such that it mimics glycosylation normally found at the neuromuscular and myotendinous junctions, and increases the extrasynaptic expression of dystrophin and laminin α2 surrogates that are known to inhibit muscular dystrophy. Preclinical studies have shown that muscle GALGT2 overexpression inhibits disease in mouse models of Duchenne Musuclar Dystrophy (DMD), Congenital Muscular Dystrophy 1A (CMD1A) and Limb Girdle Muscular Dystrophy 2D (LGMD2D). This vector utilizes an AAV serotype, rh74, that shows great efficacy at delivering gene expression to muscles when the vector is delivered via the blood, while the MCK promoter confines gene expression to muscle cells. Extensive proof-of-concept and safety studies have led to an IND for the use of rAAVrh74.MCK.GALGT2 in patients with DMD. While those clinical trials are beginning, we wish here to perform proof of concept studies that would allow for the expanded use of rAAVrh74.MCK.GALGT2 to patients with CMD1A and LGMD2D. Further studies are aimed at expanded the usefulness of rAAVrh74.MCK.GALGT2 gene therapy in DMD patients by studying whether this gene therapy can increase the therapeutic effectiveness of exon skipping therapy or therapy involving gene overexpression of follistatin, a myostatin inhibitor that builds new muscle mass. All of the experiments proposed here are directed toward rapid translation of novel therapeutic approaches for muscular dystrophies, which is the overarching goal of this CORT proposal.