title: Long-term restoration of cardiac dystrophin expression in golden retriever muscular dystrophy following rAAV6-mediated exon skipping.
abstract: Although restoration of dystrophin expression via exon skipping in both cardiac and skeletal muscle has been successfully demonstrated in the mdx mouse, restoration of cardiac dystrophin expression in large animal models of Duchenne muscular dystrophy (DMD) has proven to be a challenge. In large animals, investigators have focused on using intravenous injection of antisense oligonucleotides (AO) to mediate exon skipping. In this study, we sought to optimize restoration of cardiac dystrophin expression in the golden retriever muscular dystrophy (GRMD) model using percutaneous transendocardial delivery of recombinant AAV6 (rAAV6) to deliver a modified U7 small nuclear RNA (snRNA) carrying antisense sequence to target the exon splicing enhancers of exons 6 and 8 and correct the disrupted reading frame. We demonstrate restoration of cardiac dystrophin expression at 13 months confirmed by reverse transcription-PCR (RT-PCR) and immunoblot as well as membrane localization by immunohistochemistry. This was accompanied by improved cardiac function as assessed by cardiac magnetic resonance imaging (MRI). Percutaneous transendocardial delivery of rAAV6 expressing a modified U7 exon skipping construct is a safe, effective method for restoration of dystrophin expression and improvement of cardiac function in the GRMD canine and may be easily translatable to human DMD patients.
authors.affiliation: Department of Physiology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA. bish@mail.med.upenn.edu
authors.forename: Lawrence T
authors.initials: LT
authors.lastname: Bish
authors.forename: Meg M
authors.initials: MM
authors.lastname: Sleeper
authors.forename: Sean C
authors.initials: SC
authors.lastname: Forbes
authors.forename: Bingjing
authors.initials: B
authors.lastname: Wang
authors.forename: Caryn
authors.initials: C
authors.lastname: Reynolds
authors.forename: Gretchen E
authors.initials: GE
authors.lastname: Singletary
authors.forename: Dennis
authors.initials: D
authors.lastname: Trafny
authors.forename: Kevin J
authors.initials: KJ
authors.lastname: Morine
authors.forename: Julio
authors.initials: J
authors.lastname: Sanmiguel
authors.forename: Sylvain
authors.initials: S
authors.lastname: Cecchini
authors.forename: Tamas
authors.initials: T
authors.lastname: Virag
authors.forename: Adeline
authors.initials: A
authors.lastname: Vulin
authors.forename: Cyriaque
authors.initials: C
authors.lastname: Beley
authors.forename: Janet
authors.initials: J
authors.lastname: Bogan
authors.forename: James M
authors.initials: JM
authors.lastname: Wilson
authors.forename: Krista
authors.initials: K
authors.lastname: Vandenborne
authors.forename: Joe N
authors.initials: JN
authors.lastname: Kornegay
authors.forename: Glenn A
authors.initials: GA
authors.lastname: Walter
authors.forename: Robert M
authors.initials: RM
authors.lastname: Kotin
authors.forename: Luis
authors.initials: L
authors.lastname: Garcia
authors.forename: H Lee
authors.initials: HL
authors.lastname: Sweeney
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D002460:Cell Line; D000229:Dependovirus / Q000235:genetics*; D004195:Disease Models, Animal; D004285:Dogs; D016189:Dystrophin / Q000235:genetics* / Q000378:metabolism; D004452:Echocardiography; D005091:Exons; D005355:Fibrosis; D015870:Gene Expression; D023061:Gene Order; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000235:genetics* / Q000493:pharmacokinetics; D016679:Genome, Viral; D006801:Humans; D008279:Magnetic Resonance Imaging; D020388:Muscular Dystrophy, Duchenne / Q000175:diagnosis / Q000235:genetics* / Q000628:therapy*; D009206:Myocardium / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D016189:Dystrophin; D012333:RNA, Messenger