Antisense oligonucleotide suppression of DMD

描述(申请人提供)：该项目的最终目标是开发一种治疗Duchenne肌营养不良症(DMD)的反义寡核苷酸(AO)疗法。反义寡核苷酸可用于降低DMD的严重程度，方法是在剪接前mRNA的过程中去除特定的外显子，绕过无义突变或恢复dystrophin基因组缺失周围的阅读框架。作为治疗的结果，营养不良组织中的dystrophin表达将恢复，DMD患者理论上只会表现出较轻微的Becker肌营养不良症(BMD)表型。 该项目将探索AO的设计和交付，以将致病Dstrophin基因突变的后果降至最低。(1)肌营养不良症的动物模型将被用于开发治疗方案和评估体内的治疗效果。(2)AOS将被设计成针对人类dystrophin基因转录本中相关外显子上最易弯曲的剪接基序，并将在培养的人类肌肉细胞中进行评估。 虽然这种方法不能永久纠正原发遗传损害，但我们建议重复给药，最好是通过全身给药，应该是可行的。将开发和评估用于增加稳定性和/或摄取的化学或修饰，这些化学或修饰针对体内诱导外显子跳过而优化。只有定期服用AOS才能维持营养不良肌肉中诱导的抗肌营养不良蛋白的治疗水平。 DMD是一种严重的疾病，没有有效的治疗方法。AOS不能治愈这种毁灭性的疾病，然而，基于AO的剪接干预具有降低DMD严重程度的潜力，因此接受治疗的男孩应该能够产生一些功能性的Dstrophin。这将有望减轻DMD的严重程度，并提高患者及其家人的生活质量。

DESCRIPTION (provided by applicant): The ultimate goal of this project is to develop an antisense oligonucleotide (AO) therapy for Duchenne muscular dystrophy (DMD). Antisense oligonucleotides (AOs) can be used to reduce the severity of DMD by removing specific exons during pre-mRNA splicing, to either by-pass nonsense mutations or restore the reading frame around dystrophin genomic deletions. As a result of the treatment, dystrophin expression would be restored in dystrophic tissue and DMD patients would theoretically manifest only the milder phenotype of Becker Muscular Dystrophy (BMD). This project will explore the design and delivery of AOs to minimize the consequences of disease-causing dystrophin gene mutations. (1) Animal models of muscular dystrophy will be used to develop treatment regimens and assess therapeutic benefits in vivo. (2) AOs will be designed to target the most amenable splicing motifs at relevant exons in the human dystrophin gene transcript and will be evaluated in cultured human muscle cells. Although this approach cannot permanently correct the primary genetic lesion, we propose that repeated administration, preferably through systemic delivery, should be feasible. AO chemistries or modifications to increase stability and/or uptake, optimized for in vivo induction of exon skipping, will be developed and evaluated. Only periodic administration of AOs should be required to maintain therapeutic levels of induced dystrophin in dystrophic muscle. DMD is a serious disorder for which there is no effective treatment. AOs will not cure this devastating condition, however, AO-based splicing intervention has the potential to reduce the severity of DMD so that treated boys should be able to produce some functional dystrophin. This would be expected to moderate the severity of DMD and improve the quality of life for patients and their families.