AAV CRISPR editing rescues cardiac and muscle function for 18 months in dystrophic mice.

Published

Journal Article

Adeno-associated virus-mediated (AAV-mediated) CRISPR editing is a revolutionary approach for treating inherited diseases. Sustained, often life-long mutation correction is required for treating these diseases. Unfortunately, this has never been demonstrated with AAV CRISPR therapy. We addressed this question in the mdx model of Duchenne muscular dystrophy (DMD). DMD is caused by dystrophin gene mutation. Dystrophin deficiency leads to ambulation loss and cardiomyopathy. We treated 6-week-old mice intravenously and evaluated disease rescue at 18 months. Surprisingly, nominal dystrophin was restored in skeletal muscle. Cardiac dystrophin was restored, but histology and hemodynamics were not improved. To determine the underlying mechanism, we evaluated components of the CRISPR-editing machinery. Intriguingly, we found disproportional guide RNA (gRNA) vector depletion. To test whether this is responsible for the poor outcome, we increased the gRNA vector dose and repeated the study. This strategy significantly increased dystrophin restoration and reduced fibrosis in all striated muscles at 18 months. Importantly, skeletal muscle function and cardiac hemodynamics were significantly enhanced. Interestingly, we did not see selective depletion of the gRNA vector after intramuscular injection. Our results suggest that gRNA vector loss is a unique barrier for systemic AAV CRISPR therapy. This can be circumvented by vector dose optimization.

Full Text

Duke Authors

Cited Authors

  • Hakim, CH; Wasala, NB; Nelson, CE; Wasala, LP; Yue, Y; Louderman, JA; Lessa, TB; Dai, A; Zhang, K; Jenkins, GJ; Nance, ME; Pan, X; Kodippili, K; Yang, NN; Chen, S-J; Gersbach, CA; Duan, D

Published Date

  • December 6, 2018

Published In

Volume / Issue

  • 3 / 23

PubMed ID

  • 30518686

Pubmed Central ID

  • 30518686

Electronic International Standard Serial Number (EISSN)

  • 2379-3708

International Standard Serial Number (ISSN)

  • 2379-3708

Digital Object Identifier (DOI)

  • 10.1172/jci.insight.124297

Language

  • eng