title: Lentiviral vectors can be used for full-length dystrophin gene therapy.
abstract: Duchenne Muscular Dystrophy (DMD) is caused by a lack of dystrophin expression in patient muscle fibres. Current DMD gene therapy strategies rely on the expression of internally deleted forms of dystrophin, missing important functional domains. Viral gene transfer of full-length dystrophin could restore wild-type functionality, although this approach is restricted by the limited capacity of recombinant viral vectors. Lentiviral vectors can package larger transgenes than adeno-associated viruses, yet lentiviral vectors remain largely unexplored for full-length dystrophin delivery. In our work, we have demonstrated that lentiviral vectors can package and deliver inserts of a similar size to dystrophin. We report a novel approach for delivering large transgenes in lentiviruses, in which we demonstrate proof-of-concept for a 'template-switching' lentiviral vector that harnesses recombination events during reverse-transcription. During this work, we discovered that a standard, unmodified lentiviral vector was efficient in delivering full-length dystrophin to target cells, within a total genomic load of more than 15,000 base pairs. We have demonstrated gene therapy with this vector by restoring dystrophin expression in DMD myoblasts, where dystrophin was expressed at the sarcolemma of myotubes after myogenic differentiation. Ultimately, our work demonstrates proof-of-concept that lentiviruses can be used for permanent full-length dystrophin gene therapy, which presents a significant advancement in developing an effective treatment for DMD.
authors.affiliation: The Dubowitz Neuromuscular Centre, Molecular Neurosciences Section, Developmental Neurosciences Programme, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK.|UCL Cancer Institute, Paul O 'Gorman Building, University College London, 72 Huntley Street, London, WC1E 6BT, UK.|Molecular and Cellular Immunology, Institute of Child Health, University College London, 30 Guilford Street, London, WC1N 1EH, UK.|Gene Transfer Technology Group, Institute for Womens Health, University College London, 86-96 Chenies Mews, London, UK.
authors.forename: John R
authors.initials: JR
authors.lastname: Counsell
authors.affiliation: The Dubowitz Neuromuscular Centre, Molecular Neurosciences Section, Developmental Neurosciences Programme, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK.
authors.forename: Zeinab
authors.initials: Z
authors.lastname: Asgarian
authors.affiliation: The Dubowitz Neuromuscular Centre, Molecular Neurosciences Section, Developmental Neurosciences Programme, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK.
authors.forename: Jinhong
authors.initials: J
authors.lastname: Meng
authors.affiliation: UCL Cancer Institute, Paul O 'Gorman Building, University College London, 72 Huntley Street, London, WC1E 6BT, UK.
authors.forename: Veronica
authors.initials: V
authors.lastname: Ferrer
authors.affiliation: Molecular and Cellular Immunology, Institute of Child Health, University College London, 30 Guilford Street, London, WC1N 1EH, UK.
authors.forename: Conrad A
authors.initials: CA
authors.lastname: Vink
authors.affiliation: Molecular and Cellular Immunology, Institute of Child Health, University College London, 30 Guilford Street, London, WC1N 1EH, UK.
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Howe
authors.affiliation: Gene Transfer Technology Group, Institute for Womens Health, University College London, 86-96 Chenies Mews, London, UK.|MRC Antiviral Gene Therapy Research Unit, Faculty of Health Sciences, University of the Witswatersrand, Johannesburg, South Africa.
authors.forename: Simon N
authors.initials: SN
authors.lastname: Waddington
authors.affiliation: Molecular and Cellular Immunology, Institute of Child Health, University College London, 30 Guilford Street, London, WC1N 1EH, UK.
authors.forename: Adrian J
authors.initials: AJ
authors.lastname: Thrasher
authors.affiliation: The Dubowitz Neuromuscular Centre, Molecular Neurosciences Section, Developmental Neurosciences Programme, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK.
authors.forename: Francesco
authors.initials: F
authors.lastname: Muntoni
authors.affiliation: The Dubowitz Neuromuscular Centre, Molecular Neurosciences Section, Developmental Neurosciences Programme, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London, WC1N 1EH, UK.
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Morgan
authors.affiliation: UCL Cancer Institute, Paul O 'Gorman Building, University College London, 72 Huntley Street, London, WC1E 6BT, UK.
authors.forename: Olivier
authors.initials: O
authors.lastname: Danos
mesh_terms: D002460:Cell Line; D002675:Child, Preschool; D016189:Dystrophin / Q000235:genetics* / Q000627:therapeutic use*; D015316:Genetic Therapy; D005822:Genetic Vectors / Q000378:metabolism*; D006801:Humans; D016086:Lentivirus / Q000235:genetics*; D020388:Muscular Dystrophy, Duchenne / Q000235:genetics / Q000628:therapy; D032446:Myoblasts / Q000378:metabolism / Q000473:pathology; D013698:Templates, Genetic; D014161:Transduction, Genetic; D019076:Transgenes
chemical_list: D016189:Dystrophin