Therapeutic genetics and disease modeling in LAMA2-CMD

LAMA2-CMD 的治疗遗传学和疾病模型

• 批准号: 10363412
• 负责人: Dwi Utami Kemaladewi
• 金额: $ 44.15万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2027-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10363412
• 关键词: Address; Affect; Apoptosis; Bioenergetics; CRISPR-mediated transcriptional activation; CRISPR/Cas technology; Cell model; Cells; Cessation of life; Child; Clinical; Clinical Trials; Contracture; Data; Defect; Development; Disease; Disease model; Dose; Economics; Evaluation; Event; Expenditure; Fibrosis; Functional disorder; Future; Gene Activation; Genes; Genetic; Genetic Diseases; Genetic Models; Human; Impairment; Individual; Inflammation; Life; Longevity; Mediating; Medical; Mitochondria; Modeling; Mus; Muscular Dystrophies; Mutation; Nature; Outcome; Pathogenicity; Patients; Physical therapy; Production; Property; Proteins; Respiration; Respiratory physiology; Safety; Schwann Cells; Services; Skeletal Muscle; Splice-Site Mutation; System; Technology; Testing; Therapeutic; Therapeutic Intervention; Therapeutic Uses; Toxic effect; Toxicology; Transcription Coactivator; Translations; United States; Up-Regulation; attenuation; cell motility; congenital muscular dystrophy; cost; disease phenotype; efficacy evaluation; experimental study; improved; in vivo; migration; miniaturize; mouse model; muscular dystrophy mouse model; mutation correction; myelination; nerve damage; neuromuscular function; novel; patient population; postnatal; pre-clinical; preclinical evaluation; premature; promoter; symptom management; therapeutic evaluation; translational approach; ventilation

ABSTRACT Muscular dystrophies impact an estimated 250,000 patients in the United States, resulting in an annual medical expenditure of over $46 billion. The economic loss is more substantial in the congenital-onset muscular dystrophies (CMDs), which manifest very early in life, due to patients' inability to enter the workforce and/or their premature death. LAMA2-deficient congenital muscular dystrophy (LAMA2-CMD), the most common form of CMD, is caused by mutations in the LAMA2 gene encoding the LAMA2 protein. The lack of LAMA2 protein causes degeneration of skeletal muscle and impaired Schwann cell myelination, resulting in a cascade of secondary events that include apoptosis, inflammation, and fibrosis, which ultimately precipitate the disease. Patients are provided with disease symptom management, such as assisted ventilation, ambulatory services, and physiotherapy to reduce contractures, but there is no curative option. Owing to the genetic nature of the disease, the correction of mutations would be a promising treatment for LAMA2-CMD. We have previously described the use of CRISPR/Cas9 to correct a splice site mutation in the Lama2 gene and showed amelioration of disease phenotypes in a LAMA2-CMD mouse model. However, there are more than 600 pathogenic mutations identified in the patient populations, which significantly hampers future translation of any LAMA2 mutation correction strategy to patients. In contrast, the attenuation of disease pathogenicity by targeted modulation of the expression of disease modifier genes would be beneficial to all individuals affected with LAMA2-CMD. We were the first to develop a CRISPR activation-based approach to postnatally upregulate a disease modifier gene Lama1, which is structurally and functionally similar to Lama2, in the mouse model. These findings led to the hypothesis that targeted LAMA1 gene activation can serve as a mutation-independent therapeutic approach for LAMA2-CMD. We will test this hypothesis by performing a dedicated preclinical evaluation of efficacy and safety profiles of Lama1 upregulation in a severe LAMA2-CMD mouse model. In addition, we will bridge the translation of the strategy from a mouse-to patient-relevant models and evaluate the effect of human LAMA1 upregulation on cellular impairments, including mitochondrial respiration, migration, and myelination. Successful completion of these experiments will pave the way towards the development of mutation-independent therapeutic interventions for LAMA2-CMD and potentially other muscular dystrophies.

摘要 在美国，估计有25万名患者受到肌肉营养不良的影响，导致每年一次的医疗 支出超过460亿美元。先天性肌萎缩症的经济损失更大。 营养不良(CMD)，在生命的早期就表现出来，由于患者无法进入劳动力和/或他们的 过早死亡。LAMA2缺陷型先天性肌营养不良症(LAMA2-CMD)是最常见的 CMD是由编码LAMA2蛋白的LAMA2基因突变引起的。LAMA2蛋白的缺失 导致骨骼肌退化和雪旺细胞髓鞘形成受损，导致一系列 继发性事件，包括细胞凋亡、炎症和纤维化，最终导致疾病发生。 为患者提供疾病症状管理，如辅助通风、门诊服务、 和物理疗法来减少痉挛，但没有治愈的选择。 由于这种疾病的遗传性质，纠正突变将是一种有希望的治疗方法。 LAMA2-CMD.我们之前已经描述了使用CRISPR/Cas9来纠正剪接位点突变 LAMA2基因，并在LAMA2-CMD小鼠模型中显示出疾病表型的改善。然而，在那里 在患者群体中发现了600多种致病突变，这严重阻碍了未来 将任何LAMA2突变纠正策略翻译给患者。 相反，通过有针对性地调节疾病修饰物的表达来减弱疾病的致病性 基因对所有感染LAMA2-CMD的个体都是有益的。我们是第一个开发CRISPR的 基于激活的方法在出生后上调疾病修饰基因Lama1，该基因在结构上和 在小鼠模型中，功能类似于Lama2。这些发现导致了以LAMA1为靶点的假设 基因激活可作为LAMA2-CMD的一种非突变治疗方法。 我们将通过一项专门的临床前评估来检验这一假设。 LAMA2-CMD小鼠模型中Lama1表达上调。此外，我们还将桥接 从小鼠到患者相关模型的策略和评估人类LAMA1上调对 细胞损伤，包括线粒体呼吸、迁移和髓鞘形成。成功完成 这些实验将为开发不依赖突变的治疗干预措施铺平道路。 用于LAMA2-CMD和潜在的其他肌营养不良症。