title: In contrast to AAV-mediated Cntf expression, AAV-mediated Gdnf expression enhances gene replacement therapy in rodent models of retinal degeneration.
abstract: While AAV- and lentivirus-mediated gene replacement therapy can produce structural and functional improvements in various animal models of inherited retinal degeneration, this approach often has very limited effects on the rate of photoreceptor cell loss. Neurotrophic factors such as ciliary neurotrophic factor (CNTF) and glial cell line-derived neurotrophic factor (GDNF) have been shown to prolong photoreceptor survival in rodent models of retinal degeneration, but AAV-mediated Cntf expression also results in suppression of electrophysiological responses from the retina. In this study using mice, we show that while the deleterious effects mediated by CNTF are dose-dependent, administering a dose of CNTF that does not adversely affect retinal function precludes its ability to delay photoreceptor cell death. In evaluating GDNF as a neuroprotective agent, we show that AAV-mediated Gdnf expression does not produce adverse effects similar to those of CNTF. In addition, we demonstrate the ability of AAV-mediated delivery of Gdnf to slow cell death in two rodent models of retinitis pigmentosa and to enhance retinal function in combination with the relevant gene replacement therapy. These data show for the first time that a combination of these approaches can provide enhanced rescue over gene replacement or growth factor therapy alone.
authors.affiliation: Division of Molecular Therapy, Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK.
authors.forename: Prateek K
authors.initials: PK
authors.lastname: Buch
authors.forename: Robert E
authors.initials: RE
authors.lastname: MacLaren
authors.forename: Yanaí
authors.initials: Y
authors.lastname: Durán
authors.forename: Kamaljit S
authors.initials: KS
authors.lastname: Balaggan
authors.forename: Angus
authors.initials: A
authors.lastname: MacNeil
authors.forename: Frank C
authors.initials: FC
authors.lastname: Schlichtenbrede
authors.forename: Alexander J
authors.initials: AJ
authors.lastname: Smith
authors.forename: Robin R
authors.initials: RR
authors.lastname: Ali
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002460:Cell Line; D002470:Cell Survival; D020934:Ciliary Neurotrophic Factor / Q000235:genetics / Q000378:metabolism*; D000229:Dependovirus / Q000235:genetics*; D004195:Disease Models, Animal; D015870:Gene Expression; D015316:Genetic Therapy; D051100:Glial Cell Line-Derived Neurotrophic Factor / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007381:Intermediate Filament Proteins / Q000235:genetics / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D009474:Neurons / Q000378:metabolism / Q000473:pathology; D064531:Peripherins; D010786:Photoreceptor Cells / Q000378:metabolism / Q000473:pathology; D051381:Rats; D012162:Retinal Degeneration / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*
chemical_list: D020934:Ciliary Neurotrophic Factor; D051100:Glial Cell Line-Derived Neurotrophic Factor; D007381:Intermediate Filament Proteins; D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; D064531:Peripherins