title: Exosome-associated AAV2 vector mediates robust gene delivery into the murine retina upon intravitreal injection.
abstract: Widespread gene transfer to the retina is challenging as it requires vector systems to overcome physical and biochemical barriers to enter and diffuse throughout retinal tissue. We investigated whether exosome-associated adeno-associated virus, (exo-AAV) enabled broad retinal targeting following intravitreal (IVT) injection, as exosomes have been shown to traverse biological barriers and mediate widespread distribution upon systemic injection. We packaged an AAV genome encoding green fluorescent protein (GFP) into conventional AAV2 and exo-AAV2 vectors. Vectors were IVT injected into the eyes of adult mice. GFP expression was noninvasively monitored by fundus imaging and retinal expression was analyzed 4 weeks post-injection by qRT-PCR and histology. Exo-AAV2 outperformed conventional AAV2 in GFP expression based on fundus image analysis and qRT-PCR. Exo-AAV2 demonstrated deeper penetration in the retina, efficiently reaching the inner nuclear and outer plexiform, and to a lesser extent the outer nuclear layer. Cell targets were ganglion cells, bipolar cells, Müller cells, and photoreceptors. Exo-AAV2 serves as a robust gene delivery tool for murine retina, and the simplicity of production and isolation should make it widely applicable to basic research of the eye.
authors.affiliation: Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA.|Grousbeck Gene Therapy Center, Schepens Eye Research Institute and Massachusetts Eye and Ear, Boston, MA, USA.|Ocular Genomics Institute, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
authors.forename: Sarah J
authors.initials: SJ
authors.lastname: Wassmer
authors.affiliation: Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA.|Grousbeck Gene Therapy Center, Schepens Eye Research Institute and Massachusetts Eye and Ear, Boston, MA, USA.|Ocular Genomics Institute, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
authors.forename: Livia S
authors.initials: LS
authors.lastname: Carvalho
authors.affiliation: Department of Neurobiology and Howard Hughes Medical Institute, Harvard Medical School, 220 Longwood Avenue, Boston, 02115 MA, USA.|Department of Neurology, Massachusetts General Hospital and NeuroDiscovery Center, Harvard Medical School, Building 149, Charlestown, Boston, 02129 MA, USA.
authors.forename: Bence
authors.initials: B
authors.lastname: György
authors.affiliation: Harvard Stem Cell Institute, Harvard University, Cambridge, MA, USA.|Grousbeck Gene Therapy Center, Schepens Eye Research Institute and Massachusetts Eye and Ear, Boston, MA, USA.|Ocular Genomics Institute, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.
authors.forename: Luk H
authors.initials: LH
authors.lastname: Vandenberghe
authors.affiliation: Ocular Genomics Institute, Department of Ophthalmology, Harvard Medical School, Boston, MA, USA.|Department of Neurology, Massachusetts General Hospital and NeuroDiscovery Center, Harvard Medical School, Building 149, Charlestown, Boston, 02129 MA, USA.
authors.forename: Casey A
authors.initials: CA
authors.lastname: Maguire
mesh_terms: D000818:Animals; D000229:Dependovirus / Q000235:genetics; D055354:Exosomes / Q000235:genetics*; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000008:administration & dosage*; D049452:Green Fluorescent Proteins / Q000235:genetics*; D058449:Intravitreal Injections; D008297:Male; D051379:Mice; D012160:Retina / Q000378:metabolism*
chemical_list: D049452:Green Fluorescent Proteins