Gene-edited primary muscle stem cells rescue dysferlin-deficient muscular dystrophy

Escobar Fernandez, H.; Di Francescantonio, S.; Marg, A.; Zhogov, A.; Krishna, S.; Metzler, E.; Petkova, M.; Daumke, O.; Kuehn, R.; Spuler, S.

doi:10.1101/2024.02.12.579813

bioRxiv · 10.1101/2024.02.12.579813

Gene-edited primary muscle stem cells rescue dysferlin-deficient muscular dystrophy

Escobar Fernandez, H.·Di Francescantonio, S.·Marg, A.·Zhogov, A.·Krishna, S.·Metzler, E.·Petkova, M.·Daumke, O.·Kuehn, R.·Spuler, S.

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Abstract

Dystrophy-associated fer-1-like protein (dysferlin) conducts plasma membrane repair. Mutations in the DYSF gene cause a panoply of genetic muscular dystrophies. We targeted a frequent loss-of-function, DYSF exon 44, founder frameshift mutation with mRNA-mediated delivery of SpCas9 in combination with a mutation-specific sgRNA to primary muscle stem cells from two homozygous patients. We observed a consistent >60% exon 44 re-framing, rescuing a full-length and functional dysferlin protein. A new mouse model harboring a humanized Dysf exon 44 with the founder mutation, hEx44mut, recapitulated the patients phenotype and an identical re-framing outcome in primary muscle stem cells. Finally, gene-edited murine primary muscle stem-cells were able to regenerate muscle and rescued dysferlin when transplanted back into hEx44mut hosts. These findings are the first to show that a CRISPR-mediated therapy can ameliorate dysferlin deficiency. We suggest that gene-edited primary muscle stem cells could exhibit utility, not only in treating dysferlin deficiency syndromes, but also perhaps other forms of muscular dystrophy.

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Escobar Fernandez, H., Di Francescantonio, S., Marg, A., Zhogov, A., Krishna, S., Metzler, E., Petkova, M., Daumke, O., Kuehn, R., Spuler, S.. 2024-02-12. Gene-edited primary muscle stem cells rescue dysferlin-deficient muscular dystrophy. https://doi.org/10.1101/2024.02.12.579813

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