Antisense PMO found in dystrophic dog model was effective in cells from exon 7-deleted DMD patient

Journal article

BACKGROUND: Antisense oligonucleotide-induced exon skipping is a promising approach for treatment of Duchenne muscular dystrophy (DMD). We have systemically administered an antisense phosphorodiamidate morpholino oligomer (PMO) targeting dystrophin exons 6 and 8 to a dog with canine X-linked muscular dystrophy in Japan (CXMD(J)) lacking exon 7 and achieved recovery of dystrophin in skeletal muscle. To date, however, antisense chemical compounds used in DMD animal models have not been directly applied to a DMD patient having the same type of exon deletion. We recently identified a DMD patient with an exon 7 deletion and tried direct translation of the antisense PMO used in dog models to the DMD patient's cells. METHODOLOGY/PRINCIPAL FINDINGS: We converted fibroblasts of CXMD(J) and the DMD patient to myotubes by FACS-aided MyoD transduction. Antisense PMOs targeting identical regions of dog and human dystrophin exons 6 and 8 were designed. These antisense PMOs were mixed and administered as a cocktail to either dog or human cells in vitro. In the CXMD(J) and human DMD cells, we observed a similar efficacy of skipping of exons 6 and 8 and a similar extent of dystrophin protein recovery. The accompanying skipping of exon 9, which did not alter the reading frame, was different between cells of these two species. CONCLUSION/SIGNIFICANCE: Antisense PMOs, the effectiveness of which has been demonstrated in a dog model, achieved multi-exon skipping of dystrophin gene on the FACS-aided MyoD-transduced fibroblasts from an exon 7-deleted DMD patient, suggesting the feasibility of systemic multi-exon skipping in humans.

Authors: Saito, T; Nakamura, A; Aoki, Y; Yokota, T; Okada, T

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Public Library of Science
• Journal: PLoS ONE
• Volume: 5
• Issue: 8
• Pages: e12239
• Publication date: 2010-08-18
• Acceptance date: 2010-07-21
• DOI: 10.1371/journal.pone.0012239
• EISSN: 1932-6203
• Language: English
• Keywords: Muscular Dystrophy, Duchenne; Fibroblasts; Alternative Splicing; Disease Models, Animal; Cell Differentiation; Genetic Vectors; Dogs; Young Adult; SBTMR; Humans; DNA Mutational Analysis; Base Sequence; Sequence Deletion; MyoD Protein; Morpholinos; Morpholines; Retroviridae; Exons; Male; Transduction, Genetic; Animals