title: Effective delivery of large genes to the retina by dual AAV vectors.
abstract: Retinal gene therapy with adeno-associated viral (AAV) vectors is safe and effective in humans. However, AAV's limited cargo capacity prevents its application to therapies of inherited retinal diseases due to mutations of genes over 5 kb, like Stargardt's disease (STGD) and Usher syndrome type IB (USH1B). Previous methods based on 'forced' packaging of large genes into AAV capsids may not be easily translated to the clinic due to the generation of genomes of heterogeneous size which raise safety concerns. Taking advantage of AAV's ability to concatemerize, we generated dual AAV vectors which reconstitute a large gene by either splicing (trans-splicing), homologous recombination (overlapping), or a combination of the two (hybrid). We found that dual trans-splicing and hybrid vectors transduce efficiently mouse and pig photoreceptors to levels that, albeit lower than those achieved with a single AAV, resulted in significant improvement of the retinal phenotype of mouse models of STGD and USH1B. Thus, dual AAV trans-splicing or hybrid vectors are an attractive strategy for gene therapy of retinal diseases that require delivery of large genes.
authors.affiliation: Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy.
authors.forename: Ivana
authors.initials: I
authors.lastname: Trapani
authors.forename: Pasqualina
authors.initials: P
authors.lastname: Colella
authors.forename: Andrea
authors.initials: A
authors.lastname: Sommella
authors.forename: Carolina
authors.initials: C
authors.lastname: Iodice
authors.forename: Giulia
authors.initials: G
authors.lastname: Cesi
authors.forename: Sonia
authors.initials: S
authors.lastname: de Simone
authors.forename: Elena
authors.initials: E
authors.lastname: Marrocco
authors.forename: Settimio
authors.initials: S
authors.lastname: Rossi
authors.forename: Massimo
authors.initials: M
authors.lastname: Giunti
authors.forename: Arpad
authors.initials: A
authors.lastname: Palfi
authors.forename: Gwyneth J
authors.initials: GJ
authors.lastname: Farrar
authors.forename: Roman
authors.initials: R
authors.lastname: Polishchuk
authors.forename: Alberto
authors.initials: A
authors.lastname: Auricchio
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000378:metabolism; D000818:Animals; D000229:Dependovirus / Q000378:metabolism*; D004195:Disease Models, Animal; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000008:administration & dosage / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D007267:Injections; D008062:Lipofuscin / Q000378:metabolism; D008268:Macular Degeneration / Q000151:congenital / Q000235:genetics / Q000628:therapy; D020460:Melanosomes / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D000081412:Myosin VIIa; D009218:Myosins / Q000378:metabolism; D010641:Phenotype; D020419:Photoreceptor Cells, Vertebrate / Q000378:metabolism; D012160:Retina / Q000378:metabolism*; D055213:Retinal Pigment Epithelium / Q000378:metabolism; D012243:Rhodopsin / Q000378:metabolism; D000080362:Stargardt Disease; D034421:Sus scrofa; D020040:Trans-Splicing / Q000235:genetics; D014161:Transduction, Genetic; D052245:Usher Syndromes / Q000235:genetics / Q000628:therapy
chemical_list: D018528:ATP-Binding Cassette Transporters; C512841:Abca4 protein, mouse; D008062:Lipofuscin; C000631455:MYO7A protein, human; C000631456:Myo7a protein, mouse; D000081412:Myosin VIIa; D012243:Rhodopsin; D009218:Myosins