title: Efficient gene delivery to the cone-enriched pig retina by dual AAV vectors.
abstract: Gene therapy with adeno-associated viral (AAV) vectors is limited by AAV cargo capacity that prevents their application to the inherited retinal diseases (IRDs), such as Stargardt disease (STGD) or Usher syndrome type IB (USH1B), which are due to mutations in genes larger than 5 kb. Trans-splicing or hybrid dual AAV vectors have been successfully exploited to reconstitute large gene expression in the mouse retina. Here, we tested them in the large cone-enriched pig retina that closely mimics the human retina. We found that dual AAV trans-splicing and hybrid vectors transduce pig photoreceptors, the major cell targets for treatment of IRDs, to levels that were about two- to threefold lower than those obtained with a single AAV vector of normal size. This efficiency is significantly higher than that in mice, and is potentially due to the high levels of dual AAV co-transduction we observe in pigs. We also show that subretinal delivery in pigs of dual AAV trans-splicing and hybrid vectors successfully reconstitute, albeit at variable levels, the expression of the large genes ABCA4 and MYO7A mutated in STGD and USH1B, respectively. Our data support the potential of dual AAV vectors for large gene reconstitution in the cone-enriched pig retina that is a relevant preclinical model.
authors.affiliation: Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Colella
authors.affiliation: Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy.
authors.forename: I
authors.initials: I
authors.lastname: Trapani
authors.affiliation: Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Cesi
authors.affiliation: Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Sommella
authors.affiliation: Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Manfredi
authors.affiliation: Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Puppo
authors.affiliation: Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Iodice
authors.affiliation: Department of Ophthalmology, Second University of Naples, Naples, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Rossi
authors.affiliation: Department of Ophthalmology, Second University of Naples, Naples, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Simonelli
authors.affiliation: Department of Veterinary Morphophysiology and Animal Production, University of Bologna, Bologna, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Giunti
authors.affiliation: Department of Veterinary Morphophysiology and Animal Production, University of Bologna, Bologna, Italy.
authors.forename: M L
authors.initials: ML
authors.lastname: Bacci
authors.affiliation: 1] Telethon Institute of Genetics and Medicine (TIGEM), Naples, Italy [2] Medical Genetics, Department of Translational Medicine, Federico II University, Naples, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Auricchio
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics; D000818:Animals; D000229:Dependovirus / Q000235:genetics; D005786:Gene Expression Regulation; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors; D006801:Humans; D008268:Macular Degeneration / Q000235:genetics / Q000628:therapy; D051379:Mice; D000081412:Myosin VIIa; D009218:Myosins / Q000235:genetics; D010786:Photoreceptor Cells / Q000378:metabolism / Q000473:pathology; D000080362:Stargardt Disease; D034421:Sus scrofa; D052245:Usher Syndromes / Q000235:genetics* / Q000628:therapy
chemical_list: C056475:ABCA4 protein, human; D018528:ATP-Binding Cassette Transporters; C000631455:MYO7A protein, human; C000631456:Myo7a protein, mouse; D000081412:Myosin VIIa; D009218:Myosins