| Autor: |
Feathers KL; Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, Ann Arbor, Michigan, USA., Jia L; Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, Ann Arbor, Michigan, USA., Khan NW; Department of Ophthalmology and Visual Sciences, University of Michigan Medical School, Ann Arbor, Michigan, USA., Smith AJ; Centre for Stem Cells & Regenerative Medicine, King's College London, London, United Kingdom., Ma JX; Department of Biochemistry, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA., Ali RR; Centre for Stem Cells & Regenerative Medicine, King's College London, London, United Kingdom., Thompson DA; Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan, USA. |
| Abstrakt: |
The use of AAV-RPE65 vectors for gene supplementation has achieved spectacular success as a treatment for individuals with autosomal recessive retinal disease caused by biallelic mutations in the visual cycle gene RPE65 . However, the efficacy of this approach in treating autosomal dominant retinitis pigmentosa (adRP) associated with a monoallelic mutation encoding a rare D477G RPE65 variant has not been studied. Although lacking a severe phenotype, we now find that knock-in mice heterozygous for D477G RPE65 (D477G KI mice) can be used to evaluate outcomes of AAV-RPE65 gene supplementation. Total RPE65 protein levels, which are decreased in heterozygous D477G KI mice, were doubled following subretinal delivery of rAAV2/5.hRPE65p.hRPE65 . In addition, rates of recovery of the chromophore 11- cis retinal after bleaching were significantly increased in eyes that received AAV-RPE65 , consistent with increased RPE65 isomerase activity. While dark-adapted chromophore levels and a-wave amplitudes were not affected, b-wave recovery rates were modestly improved. The present findings establish that gene supplementation enhances 11- cis retinal synthesis in heterozygous D477G KI mice and complement previous studies showing that chromophore therapy results in improved vision in individuals with adRP associated with D477G RPE65. |
