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Cristante E, Liyanage SE, Smith AJ, Ali RR, Bainbridge JWB. Role of HIF1α and HIF2α in Cre Recombinase-Induced Retinal Pigment Epithelium Pathology and Its Secondary Effect on Choroidal Neovascularization. Am J Pathol 2023; 193:1694-1705. [PMID: 37330004 DOI: 10.1016/j.ajpath.2023.05.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Revised: 05/09/2023] [Accepted: 05/19/2023] [Indexed: 06/19/2023]
Abstract
CreTrp1 mice are widely used for conditional retinal pigment epithelium (RPE) gene function studies. Like other Cre/LoxP models, phenotypes in CreTrp1 mice can be affected by Cre-mediated cellular toxicity, leading to RPE dysfunction, altered morphology and atrophy, activation of innate immunity, and consequent impairment of photoreceptor function. These effects are common among the age-related alterations of RPE that feature in early/intermediate forms of age-related macular degeneration. This article characterizes Cre-mediated pathology in the CreTrp1 line to elucidate the impact of RPE degeneration on both developmental and pathologic choroidal neovascularization. Nonredundant roles of the two major components of the hypoxia-inducible factor (HIF) family of transcription regulators, HIF1α and HIF2α, were identified. Genetic ablation of Hif1a protected against Cre-induced degeneration of RPE and choroid, whereas ablation of Hif2a exacerbated this degeneration. Furthermore, HIF1α deficiency protected CreTrp1 mice against laser-induced choroidal neovascularization, whereas HIF2α deficiency exacerbated the phenotype. Cre-mediated degeneration of the RPE in CreTrp1 mice offers an opportunity to investigate the impact of hypoxia signaling in the context of RPE degeneration. These findings indicate that HIF1α promotes Cre recombinase-mediated RPE degeneration and laser-induced choroidal neovascularization, whereas HIF2α is protective.
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Affiliation(s)
| | | | - Alexander J Smith
- Centre for Cell and Gene Therapy, King's College London, Guy's Hospital, London, United Kingdom
| | - Robin R Ali
- Centre for Cell and Gene Therapy, King's College London, Guy's Hospital, London, United Kingdom
| | - James W B Bainbridge
- UCL Institute of Ophthalmology London, United Kingdom; NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.
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2
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Zihni C, Georgiadis A, Ramsden CM, Sanchez-Heras E, Haas AJ, Nommiste B, Semenyuk O, Bainbridge JWB, Coffey PJ, Smith AJ, Ali RR, Balda MS, Matter K. Spatiotemporal control of actomyosin contractility by MRCKβ signaling drives phagocytosis. J Biophys Biochem Cytol 2022; 221:213476. [PMID: 36121394 PMCID: PMC9485704 DOI: 10.1083/jcb.202012042] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 07/08/2022] [Accepted: 08/19/2022] [Indexed: 12/24/2022] Open
Abstract
Phagocytosis requires actin dynamics, but whether actomyosin contractility plays a role in this morphodynamic process is unclear. Here, we show that in the retinal pigment epithelium (RPE), particle binding to Mer Tyrosine Kinase (MerTK), a widely expressed phagocytic receptor, stimulates phosphorylation of the Cdc42 GEF Dbl3, triggering activation of MRCKβ/myosin-II and its coeffector N-WASP, membrane deformation, and cup formation. Continued MRCKβ/myosin-II activity then drives recruitment of a mechanosensing bridge, enabling cytoskeletal force transmission, cup closure, and particle internalization. In vivo, MRCKβ is essential for RPE phagocytosis and retinal integrity. MerTK-independent activation of MRCKβ signaling by a phosphomimetic Dbl3 mutant rescues phagocytosis in retinitis pigmentosa RPE cells lacking functional MerTK. MRCKβ is also required for efficient particle translocation from the cortex into the cell body in Fc receptor–mediated phagocytosis. Thus, conserved MRCKβ signaling at the cortex controls spatiotemporal regulation of actomyosin contractility to guide distinct phases of phagocytosis in the RPE and represents the principle phagocytic effector pathway downstream of MerTK.
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Affiliation(s)
- Ceniz Zihni
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Anastasios Georgiadis
- UCL Institute of Ophthalmology, University College London, London, UK.,Gene and Cell Therapy Group, UCL Institute of Ophthalmology, University College London, London, UK
| | - Conor M Ramsden
- UCL Institute of Ophthalmology, University College London, London, UK
| | | | - Alexis J Haas
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Britta Nommiste
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Olha Semenyuk
- UCL Institute of Ophthalmology, University College London, London, UK.,Gene and Cell Therapy Group, UCL Institute of Ophthalmology, University College London, London, UK
| | - James W B Bainbridge
- UCL Institute of Ophthalmology, University College London, London, UK.,Gene and Cell Therapy Group, UCL Institute of Ophthalmology, University College London, London, UK.,National Institute for Health and Care Research Biomedical Research Centre at Moorfields Eye Hospital National Health Service Foundation Trust, London, UK
| | - Peter J Coffey
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Alexander J Smith
- Gene and Cell Therapy Group, UCL Institute of Ophthalmology, University College London, London, UK
| | - Robin R Ali
- UCL Institute of Ophthalmology, University College London, London, UK.,Gene and Cell Therapy Group, UCL Institute of Ophthalmology, University College London, London, UK.,National Institute for Health and Care Research Biomedical Research Centre at Moorfields Eye Hospital National Health Service Foundation Trust, London, UK
| | - Maria S Balda
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Karl Matter
- UCL Institute of Ophthalmology, University College London, London, UK
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3
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West EL, Majunder P, Naeem A, Fernando M, O'Hara-Wright M, Lanning E, Kloc M, Ribeiro J, Ovando-Roche P, Shum IO, Jumbu N, Sampson R, Hayes M, Bainbridge JWB, Georgiadis A, Smith AJ, Gonzalez-Cordero A, Ali RR. Antioxidant and lipid supplementation improve the development of photoreceptor outer segments in pluripotent stem cell-derived retinal organoids. Stem Cell Reports 2022; 17:775-788. [PMID: 35334217 PMCID: PMC9023802 DOI: 10.1016/j.stemcr.2022.02.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 02/26/2022] [Accepted: 02/28/2022] [Indexed: 01/01/2023] Open
Abstract
The generation of retinal organoids from human pluripotent stem cells (hPSC) is now a well-established process that in part recapitulates retinal development. However, hPSC-derived photoreceptors that exhibit well-organized outer segment structures have yet to be observed. To facilitate improved inherited retinal disease modeling, we determined conditions that would support outer segment development in maturing hPSC-derived photoreceptors. We established that the use of antioxidants and BSA-bound fatty acids promotes the formation of membranous outer segment-like structures. Using new protocols for hPSC-derived retinal organoid culture, we demonstrated improved outer segment formation for both rod and cone photoreceptors, including organized stacked discs. Using these enhanced conditions to generate iPSC-derived retinal organoids from patients with X-linked retinitis pigmentosa, we established robust cellular phenotypes that could be ameliorated following adeno-associated viral vector-mediated gene augmentation. These findings should aid both disease modeling and the development of therapeutic approaches for the treatment of photoreceptor disorders. Antioxidants and lipids are required for the formation of organized outer segments Both rod and cone hPSC-derived photoreceptors generate well-formed outer segments Improved conditions provide a robust model of X-linked retinitis pigmentosa type 3 Enhanced segment formation permits the evaluation of therapeutic interventions
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Affiliation(s)
- Emma L West
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Paromita Majunder
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Arifa Naeem
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Milan Fernando
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Emily Lanning
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Magdalena Kloc
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Joana Ribeiro
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Ian O Shum
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Neeraj Jumbu
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Robert Sampson
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Matt Hayes
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - James W B Bainbridge
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, City Road, London EC1V 2PD, UK
| | | | - Alexander J Smith
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Robin R Ali
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, City Road, London EC1V 2PD, UK; Kellogg Eye Center, University of Michigan, 1000 Wall Street, Ann Arbor, MI 48105, USA.
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4
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Ribeiro J, Procyk CA, West EL, O'Hara-Wright M, Martins MF, Khorasani MM, Hare A, Basche M, Fernando M, Goh D, Jumbo N, Rizzi M, Powell K, Tariq M, Michaelides M, Bainbridge JWB, Smith AJ, Pearson RA, Gonzalez-Cordero A, Ali RR. Restoration of visual function in advanced disease after transplantation of purified human pluripotent stem cell-derived cone photoreceptors. Cell Rep 2021; 35:109022. [PMID: 33882303 PMCID: PMC8065177 DOI: 10.1016/j.celrep.2021.109022] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 01/08/2021] [Accepted: 03/31/2021] [Indexed: 12/19/2022] Open
Abstract
Age-related macular degeneration and other macular diseases result in the loss of light-sensing cone photoreceptors, causing irreversible sight impairment. Photoreceptor replacement may restore vision by transplanting healthy cells, which must form new synaptic connections with the recipient retina. Despite recent advances, convincing evidence of functional connectivity arising from transplanted human cone photoreceptors in advanced retinal degeneration is lacking. Here, we show restoration of visual function after transplantation of purified human pluripotent stem cell-derived cones into a mouse model of advanced degeneration. Transplanted human cones elaborate nascent outer segments and make putative synapses with recipient murine bipolar cells (BCs), which themselves undergo significant remodeling. Electrophysiological and behavioral assessments demonstrate restoration of surprisingly complex light-evoked retinal ganglion cell responses and improved light-evoked behaviors in treated animals. Stringent controls exclude alternative explanations, including material transfer and neuroprotection. These data provide crucial validation for photoreceptor replacement therapy and for the potential to rescue cone-mediated vision.
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Affiliation(s)
- Joana Ribeiro
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Emma L West
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Monica F Martins
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Aura Hare
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Mark Basche
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Milan Fernando
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Debbie Goh
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Neeraj Jumbo
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Matteo Rizzi
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Kate Powell
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Menahil Tariq
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | | | - Alexander J Smith
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Rachael A Pearson
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Robin R Ali
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; Kellogg Eye Centre, University of Michigan, 1000 Wall St., Ann Arbor, MI 48105, USA.
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5
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Pasu S, Bell L, Zenasni Z, Lanz D, Simmonds IA, Thompson A, Yorston D, Laidlaw DAH, Bunce C, Hooper R, Bainbridge JWB. Facedown Positioning Following Surgery for Large Full-Thickness Macular Hole: A Multicenter Randomized Clinical Trial. JAMA Ophthalmol 2021; 138:725-730. [PMID: 32379288 PMCID: PMC7206530 DOI: 10.1001/jamaophthalmol.2020.0987] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Importance The value of facedown positioning following surgery for large full-thickness macular holes is unknown. Objective To determine whether advice to position facedown postoperatively improves the outcome for large macular holes. Design, Setting, and Participants This randomized, parallel group superiority trial with 1:1 randomization stratified by site with 3 months' follow-up was conducted at 9 sites across the United Kingdom and included participants with an idiopathic full-thickness macular hole of at least 400 μm minimum linear diameter and a duration of fewer than 12 months. All participants had vitrectomy surgery with peeling of the internal limiting membrane and injection of perfluoropropane (14%) gas, with or without simultaneous surgery for cataract. Interventions Following surgery, participants were randomly advised to position either facedown or face forward for 8 hours daily for 5 days. Main Outcomes and Measures The primary outcome was closure of the macular hole determined 3 months following surgery by masked optical coherence tomography evaluation. Secondary outcome measures at 3 months were visual acuity, participant-reported experience of positioning, and quality of life measured by the National Eye Institute Visual Function Questionnaire 25. Results A total of 185 participants (45 men [24.3%]; 156 white [84.3%]; 9 black [4.9%]; 10 Asian [5.4%]; median age, 69 years [interquartile range, 64-73 years]) were randomized. Macular hole closure was observed in 90 (85.6%) who were advised to position face forward and 88 (95.5%) advised to position facedown (adjusted odds ratio, 3.15; 95% CI, 0.87-11.41; P = .08). The mean (SD) improvement in best-corrected visual acuity at 3 months was 0.34 (0.69) logMAR (equivalent to 1 Snellen line) in the face-forward group and 0.57 (0.42) logMAR (equivalent to 3 Snellen lines) in the facedown group (adjusted mean difference, 0.22 [95 % CI, 0.05-0.38]; equivalent to 2 Snellen lines); 95% CI, 0.05-0.38; P = .01). The median National Eye Institute Visual Function Questionnaire 25 score was 89 (interquartile range, 76-94) in the facedown group and 87 (interquartile range, 73-93) in the face-forward group (mean [SD] change on a logistic scale, 0.08 [0.26] face forward and 0.11 [0.25] facedown; adjusted mean [SD] difference on a logistic scale, 0.02; 95% CI, -0.03 to 0.07; P = .41). Conclusions and Relevance The results do not prove that facedown positioning following surgery is more likely to close large macular holes compared with facing forward but do support the possibility that visual acuity outcomes may be superior. Trial Registration Isrctn.org Identifier: 12410596.
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Affiliation(s)
- Saruban Pasu
- National Institute of Health Research Biomedical Research Centre (BRC), Moorfields Eye Hospital National Health Service (NHS) Foundation Trust, UCL Institute of Ophthalmology, London, England.,Moorfields Eye Hospital NHS Foundation Trust, London, England.,UCL Institute of Ophthalmology, London, England
| | - Lauren Bell
- Pragmatic Clinical Trial Unit, Queen Mary University of London, London, England.,Blizard Institute, Barts and The London School of Medicine and Dentistry, London, England
| | - Zohra Zenasni
- Pragmatic Clinical Trial Unit, Queen Mary University of London, London, England.,Blizard Institute, Barts and The London School of Medicine and Dentistry, London, England
| | - Doris Lanz
- Pragmatic Clinical Trial Unit, Queen Mary University of London, London, England.,Blizard Institute, Barts and The London School of Medicine and Dentistry, London, England
| | - Irene A Simmonds
- Pragmatic Clinical Trial Unit, Queen Mary University of London, London, England.,Blizard Institute, Barts and The London School of Medicine and Dentistry, London, England
| | - Ann Thompson
- Pragmatic Clinical Trial Unit, Queen Mary University of London, London, England.,Blizard Institute, Barts and The London School of Medicine and Dentistry, London, England
| | | | | | - Catey Bunce
- National Institute of Health Research Biomedical Research Centre (BRC), Moorfields Eye Hospital National Health Service (NHS) Foundation Trust, UCL Institute of Ophthalmology, London, England.,Moorfields Eye Hospital NHS Foundation Trust, London, England.,Department of Primary Care and Public Health Sciences, King's College London, London, England
| | - Richard Hooper
- Pragmatic Clinical Trial Unit, Queen Mary University of London, London, England.,Blizard Institute, Barts and The London School of Medicine and Dentistry, London, England
| | - James W B Bainbridge
- National Institute of Health Research Biomedical Research Centre (BRC), Moorfields Eye Hospital National Health Service (NHS) Foundation Trust, UCL Institute of Ophthalmology, London, England.,Moorfields Eye Hospital NHS Foundation Trust, London, England.,UCL Institute of Ophthalmology, London, England
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6
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Kumaran N, Ali RR, Tyler NA, Bainbridge JWB, Michaelides M, Rubin GS. Validation of a Vision-Guided Mobility Assessment for RPE65-Associated Retinal Dystrophy. Transl Vis Sci Technol 2020; 9:5. [PMID: 32953245 PMCID: PMC7476654 DOI: 10.1167/tvst.9.10.5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 07/22/2020] [Indexed: 11/24/2022] Open
Abstract
Purpose To validate a vision-guided mobility assessment for individuals affected by RPE65-associated retinal dystrophy (RPE65-RD). Methods In this comparative cross-sectional study, 29 subjects, comprising 19 subjects with RPE65-RD and 10 normally-sighted subjects undertook three assessments of mobility: following a straight line, navigating a simple maze, and stepping over a sidewalk "kerb." Performance was quantified as the time taken to complete each assessment, number of errors made, walking speed, and percent preferred walking speed, for each assessment. Subjects also undertook assessments of visual acuity, contrast sensitivity, full-field static perimetry, and age-appropriate quality of life questionnaires. To identify the most relevant metric to quantify vision-guided mobility, we investigated repeatability, as well as convergent, discriminant, and criterion validity. We also measured the effect of illumination on mobility. Results Walking speed through the maze assessment best discriminated between RPE65-RD and normally-sighted subjects, with both convergent and discriminant validity. Walking speed also approached statistical significance when assessed for criterion validity (P = 0.052). Subjects with RPE65-RD had quantifiably poorer mobility at lower illumination levels. A relatively small mean difference (-0.09 m/s) was identified in comparison to a relatively large repeatability coefficient (1.10 m/s). Conclusions We describe a novel, quantifiable, repeatable, and valid assessment of mobility designed specifically for subjects with RPE65-RD. The assessment is sensitive to the visual impairment of individuals with RPE65-RD in low illumination, identifies the known phenotypic heterogeneity and will furthermore provide an important outcome measure for RPE65-RD. Translational Relevance This assessment of vision-guided mobility, validated in a dedicated cohort of subjects with RPE65-RD, is a relevant and quantifiable outcome measure for RPE65-RD.
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Affiliation(s)
- Neruban Kumaran
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital, London, UK.,Guy's and St. Thomas' NHS Foundation Trust, London, UK
| | - Robin R Ali
- UCL Institute of Ophthalmology, University College London, London, UK.,NIHR Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, UK
| | - Nick A Tyler
- Department of Civil, Environmental and Geomatic Engineering, University College London, London, UK
| | - James W B Bainbridge
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital, London, UK.,NIHR Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, UK
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital, London, UK.,NIHR Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, UK
| | - Gary S Rubin
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital, London, UK.,NIHR Moorfields Biomedical Research Centre, Moorfields Eye Hospital, London, UK
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Kumaran N, Georgiou M, Bainbridge JWB, Bertelsen M, Larsen M, Blanco-Kelly F, Ayuso C, Tran HV, Munier FL, Kalitzeos A, Michaelides M. Retinal Structure in RPE65-Associated Retinal Dystrophy. Invest Ophthalmol Vis Sci 2020; 61:47. [PMID: 32347917 PMCID: PMC7401957 DOI: 10.1167/iovs.61.4.47] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Purpose RPE65-associated retinal dystrophy (RPE65-RD) is an early onset, progressive, severe retinal dystrophy. We sought to characterize the natural history of retinal degeneration in affected individuals. Methods We performed cross-sectional and longitudinal quantitative and qualitative assessments of retinal architecture in RPE65-RD using spectral domain optical coherence tomography (SD-OCT) and fundus autofluorescence (FAF) imaging. Twenty-six subjects (mean age, 14.8 years, range, 5-24 years) with RPE65-RD underwent SD-OCT and FAF imaging, of whom 14 subjects were followed up over time. Foveal thickness (FT), outer nuclear layer thickness (ONLT), ellipsoid zone width (EZW), and ellipsoid zone area (EZA) were calculated where possible. These were correlated with age, best corrected visual acuity (BCVA), and central 30° retinal sensitivity (V30). Intra-observer agreement, test-retest repeatability, and interocular symmetry were also investigated. Results We identified structural interocular symmetry, the presence of autofluorescence in 46% (12/26) of subjects, and the presence of foveal hypoplasia (associated with significantly worse BCVA) in 50% of subjects. EZW and EZA were measurable in 67% (35/52) and 37% (19/52) of eyes, respectively, with both demonstrating good agreement on repeated measurement. The annual rate of progression using EZW was -300.63 µm/year, and -1.17 mm2/year in EZA. EZW was found to have a statistically significant correlation with BCVA and V30. Conclusions We identified the presence of autofluorescence in half of our subjects, with foveal hypoplasia also noted in half of our cohort. EZW, and to a lesser extent EZA, were robust measures of retinal degeneration and represent valuable metrics to determine the impact of intervention. (ClinicalTrials.gov number NCT02714816.).
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Del Amo EM, Griffiths JR, Klaska IP, Hoke J, White A, Aarons L, Cooper GJS, Bainbridge JWB, Bishop PN, Unwin RD. Intravitreal Pharmacokinetic Study of the Antiangiogenic Glycoprotein Opticin. Mol Pharm 2020; 17:2390-2397. [PMID: 32437164 PMCID: PMC7341526 DOI: 10.1021/acs.molpharmaceut.0c00151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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Opticin is an endogenous vitreous
glycoprotein that may have therapeutic
potential as it has been shown that supranormal concentrations suppress
preretinal neovascularization. Herein we investigated the pharmacokinetics
of opticin following intravitreal injection in rabbits. To measure
simultaneously concentrations of human and rabbit opticin, a selected
reaction monitoring mass spectrometry assay was developed. The mean
concentration of endogenous rabbit opticin in 7 uninjected eyes was
measured and found to be 19.2 nM or 0.62 μg/mL. When the vitreous
was separated by centrifugation into a supernatant and collagen-containing
pellet, 94% of the rabbit opticin was in the supernatant. Intravitreal
injection of human opticin (40 μg) into both eyes of rabbits
was followed by enucleation at 5, 24, and 72 h and 7, 14, and 28 days
postinjection (n = 6 at each time point) and measurement
of vitreous human and rabbit opticin concentrations in the supernatant
and collagen-containing pellet following centrifugation. The volume
of distribution of human opticin was calculated to be 3.31 mL, and
the vitreous half-life was 4.2 days. Assuming that rabbit and human
opticin are cleared from rabbit vitreous at the same rate, opticin
is secreted into the vitreous at a rate of 0.14 μg/day. We conclude
that intravitreally injected opticin has a vitreous half-life that
is similar to currently available antiangiogenic therapeutics. While
opticin was first identified bound to vitreous collagen fibrils, here
we demonstrate that >90% of endogenous opticin is not bound to
collagen.
Endogenous opticin is secreted by the nonpigmented ciliary epithelium
into the rabbit vitreous at a remarkably high rate, and the turnover
in vitreous is approximately 15% per day.
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Affiliation(s)
- Eva M Del Amo
- Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine & Health (FBMH), University of Manchester, Manchester M13 9PT, United Kingdom
| | - John R Griffiths
- Division of Cardiovascular Sciences, School of Medical Sciences, FBMH, University of Manchester, Manchester M13 9PT, United Kingdom
| | - Izabela P Klaska
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, United Kingdom
| | - Justin Hoke
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, United Kingdom
| | - Anne White
- Division of Evolution & Genomic Sciences, School of Biological Sciences, FBMH, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Leon Aarons
- Division of Pharmacy and Optometry, School of Health Sciences, Faculty of Biology, Medicine & Health (FBMH), University of Manchester, Manchester M13 9PT, United Kingdom
| | - Garth J S Cooper
- Division of Cardiovascular Sciences, School of Medical Sciences, FBMH, University of Manchester, Manchester M13 9PT, United Kingdom
| | - James W B Bainbridge
- UCL Institute of Ophthalmology, University College London, London EC1V 9EL, United Kingdom
| | - Paul N Bishop
- Division of Evolution & Genomic Sciences, School of Biological Sciences, FBMH, University of Manchester, Manchester M13 9PL, United Kingdom.,Manchester Royal Eye Hospital, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester M13 9WL, United Kingdom
| | - Richard D Unwin
- Division of Cardiovascular Sciences, School of Medical Sciences, FBMH, University of Manchester, Manchester M13 9PT, United Kingdom.,Stoller Biomarker Discovery Centre and Division of Cancer Sciences, School of Medical Sciences, FBMH, University of Manchester, Manchester M13 9PL, United Kingdom
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9
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Thompson DA, Iannaccone A, Ali RR, Arshavsky VY, Audo I, Bainbridge JWB, Besirli CG, Birch DG, Branham KE, Cideciyan AV, Daiger SP, Dalkara D, Duncan JL, Fahim AT, Flannery JG, Gattegna R, Heckenlively JR, Heon E, Jayasundera KT, Khan NW, Klassen H, Leroy BP, Molday RS, Musch DC, Pennesi ME, Petersen-Jones SM, Pierce EA, Rao RC, Reh TA, Sahel JA, Sharon D, Sieving PA, Strettoi E, Yang P, Zacks DN. Advancing Clinical Trials for Inherited Retinal Diseases: Recommendations from the Second Monaciano Symposium. Transl Vis Sci Technol 2020; 9:2. [PMID: 32832209 PMCID: PMC7414644 DOI: 10.1167/tvst.9.7.2] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Accepted: 03/12/2020] [Indexed: 12/18/2022] Open
Abstract
Major advances in the study of inherited retinal diseases (IRDs) have placed efforts to develop treatments for these blinding conditions at the forefront of the emerging field of precision medicine. As a result, the growth of clinical trials for IRDs has increased rapidly over the past decade and is expected to further accelerate as more therapeutic possibilities emerge and qualified participants are identified. Although guided by established principles, these specialized trials, requiring analysis of novel outcome measures and endpoints in small patient populations, present multiple challenges relative to study design and ethical considerations. This position paper reviews recent accomplishments and existing challenges in clinical trials for IRDs and presents a set of recommendations aimed at rapidly advancing future progress. The goal is to stimulate discussions among researchers, funding agencies, industry, and policy makers that will further the design, conduct, and analysis of clinical trials needed to accelerate the approval of effective treatments for IRDs, while promoting advocacy and ensuring patient safety.
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Affiliation(s)
- Debra A Thompson
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Alessandro Iannaccone
- Department of Ophthalmology, Duke Eye Center, Duke University Medical Center, Durham, NC, USA
| | - Robin R Ali
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA.,Institute of Ophthalmology, University College London, London, UK
| | - Vadim Y Arshavsky
- Department of Ophthalmology, Duke Eye Center, Duke University Medical Center, Durham, NC, USA
| | - Isabelle Audo
- Sorbonne Université, Institut de la Vision, INSERM, CNRS, Paris, France.,CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, Paris, France
| | | | - Cagri G Besirli
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Kari E Branham
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Artur V Cideciyan
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Steven P Daiger
- Human Genetics Center, School of Public Health, University of Texas Health Science Center Houston, Houston, TX, USA
| | - Deniz Dalkara
- Sorbonne Université, Institut de la Vision, INSERM, CNRS, Paris, France
| | - Jacque L Duncan
- Department of Ophthalmology, University of California-San Francisco, San Francisco, CA, USA
| | - Abigail T Fahim
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - John G Flannery
- Helen Wills Neuroscience Institute, University of California-Berkeley, Berkeley, CA, USA
| | | | - John R Heckenlively
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Elise Heon
- Department of Ophthalmology and Vision Sciences, Hospital for Sick Children, Toronto, Ontario, Canada
| | - K Thiran Jayasundera
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Naheed W Khan
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Henry Klassen
- Gavin Herbert Eye Institute, Stem Cell Research Center, University of California-Irvine, Irvine, CA, USA
| | - Bart P Leroy
- Department of Ophthalmology and Center Medical Genetics, Ghent University Hospital and University, Ghent, Belgium.,Division of Ophthalmology and Center for Cellular and Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Robert S Molday
- Department of Biochemistry/Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - David C Musch
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Mark E Pennesi
- Department of Ophthalmology, Casey Eye Institute, Oregon Health and Science Center, Portland, OR, USA
| | - Simon M Petersen-Jones
- Small Animal Clinical Sciences, Michigan State University, College of Veterinary Medicine, East Lansing, MI, USA
| | - Eric A Pierce
- Ocular Genomics Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA
| | - Rajesh C Rao
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Thomas A Reh
- Department of Biological Structure, University of Washington, Seattle, WA, USA
| | - Jose A Sahel
- Sorbonne Université, Institut de la Vision, INSERM, CNRS, Paris, France.,CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, Paris, France.,Fondation Ophtalmologique Rothschild, Paris, France.,Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Dror Sharon
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Paul A Sieving
- Department of Ophthalmology and Center for Ocular Regenerative Therapy, University of California-Davis School of Medicine, Sacramento, CA, USA.,National Eye Institute, National Institutes of Health, Bethesda, MD, USA
| | - Enrica Strettoi
- Institute of Neuroscience, National Research Council (CNR), Pisa, Italy
| | - Paul Yang
- Department of Ophthalmology, Casey Eye Institute, Oregon Health and Science Center, Portland, OR, USA
| | - David N Zacks
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
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10
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Guimaraes TACD, Georgiou M, Bainbridge JWB, Michaelides M. Gene therapy for neovascular age-related macular degeneration: rationale, clinical trials and future directions. Br J Ophthalmol 2020; 105:151-157. [PMID: 32269060 PMCID: PMC7848059 DOI: 10.1136/bjophthalmol-2020-316195] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 03/18/2020] [Accepted: 03/20/2020] [Indexed: 01/19/2023]
Abstract
Age-related macular degeneration (AMD) is one of the leading causes of irreversible blindness in the developed world. Antivascular endothelial growth factor therapy has transformed the management and outcome of neovascular AMD (nAMD), although the need for repeated intravitreal injections—even lifelong—and the related complications, high drug costs, frequent clinic visits and repeated imaging have resulted in an enormous burden both to healthcare systems and patients. The application of gene therapy approaches for sustained delivery of a range of antiangiogenic proteins has the promise of helping to address these aforementioned challenges. A number of early phase clinical trials of gene therapy in nAMD have provided encouraging results, with many more ongoing or anticipated. There remain significant areas of controversy, including regarding the optimal treatment targets, routes of administration and potential safety concerns. In this review we aim to provide an update of the current status of gene therapy for nAMD and briefly discuss future prospects.
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Affiliation(s)
| | - Michalis Georgiou
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital, London, UK
| | - James W B Bainbridge
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital, London, UK
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, UK .,Moorfields Eye Hospital, London, UK
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11
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Kumaran N, Rubin GS, Kalitzeos A, Fujinami K, Bainbridge JWB, Weleber RG, Michaelides M. A Cross-Sectional and Longitudinal Study of Retinal Sensitivity in RPE65-Associated Leber Congenital Amaurosis. Invest Ophthalmol Vis Sci 2019; 59:3330-3339. [PMID: 30025081 PMCID: PMC6040235 DOI: 10.1167/iovs.18-23873] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose RPE65-associated Leber congenital amaurosis (RPE65-LCA) is an early-onset severe retinal dystrophy associated with progressive visual field loss. Phase I/II and III gene therapy trials have identified improved retinal sensitivity but little is known about the natural history of retinal sensitivity in RPE65-LCA. Methods A total of 19 subjects (aged 9 to 23 years) undertook monocular full-field static perimetry of which 13 subjects were monitored longitudinally. Retinal sensitivity was measured as mean sensitivity (MS) and volumetrically quantified (in decibel-steradian) using visual field modeling and analysis software for the total (VTOT), central 30° (V30) and central 15° (V15) visual field. Correlation was evaluated between retinal sensitivity and age, best-corrected visual acuity (BCVA), contrast sensitivity, vision-related quality of life, and genotype. Test-retest reliability was also investigated. Results V30 was identified to have a strong, weak, and moderate correlation with age, BCVA and contrast sensitivity respectively. Furthermore, V30 was identified as having a weak linear relationship with the mobility and independence domains of the vision-related quality of life questionnaire. Longitudinal analysis demonstrated a slow loss of retinal sensitivity in this cohort. Subjects with at least one RPE65 nonsense variant appeared to show greater progressive loss of retinal sensitivity in the second decade of life than those without. Conclusions Volumetric assessment of central 30° visual field sensitivity, V30, is a useful independent measure of retinal function and, in our data, represented the best metric to monitor deterioration of retinal sensitivity in RPE65-LCA. Furthermore, functional correlation with genotype may enable more informed prognostic counseling. (ClinicalTrials.gov number, NCT02714816.)
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Affiliation(s)
- Neruban Kumaran
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - Gary S Rubin
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - Angelos Kalitzeos
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - Kaoru Fujinami
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom.,National Institute of Sensory Organs, National Hospital Organization, Tokyo Medical Center, Tokyo, Japan.,Keio University, School of Medicine, Tokyo, Japan
| | - James W B Bainbridge
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - Richard G Weleber
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, United States
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
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12
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Georgiadis A, Duran Y, Ribeiro J, Abelleira-Hervas L, Robbie SJ, Sünkel-Laing B, Fourali S, Gonzalez-Cordero A, Cristante E, Michaelides M, Bainbridge JWB, Smith AJ, Ali RR. Correction: Development of an optimized AAV2/5 gene therapy vector for Leber congenital amaurosis owing to defects in RPE65. Gene Ther 2018; 25:450. [PMID: 30046128 PMCID: PMC6328849 DOI: 10.1038/s41434-018-0031-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The authors originally published this article under the incorrect license type; this has now been corrected and is published under the CC-BY license.
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Affiliation(s)
- A Georgiadis
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - Y Duran
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - J Ribeiro
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - L Abelleira-Hervas
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - S J Robbie
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - B Sünkel-Laing
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - S Fourali
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - A Gonzalez-Cordero
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - E Cristante
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - M Michaelides
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
- NIHR Biomedical Research Centre at Moorfields Eye Hospital, London, EC1V 2PD, UK
| | - J W B Bainbridge
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
- NIHR Biomedical Research Centre at Moorfields Eye Hospital, London, EC1V 2PD, UK
| | - A J Smith
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK
| | - R R Ali
- Department of Genetics, UCL Institute of Ophthalmology, London, EC1V 9EL, UK.
- NIHR Biomedical Research Centre at Moorfields Eye Hospital, London, EC1V 2PD, UK.
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13
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Kumaran N, Ripamonti C, Kalitzeos A, Rubin GS, Bainbridge JWB, Michaelides M. Severe Loss of Tritan Color Discrimination in RPE65 Associated Leber Congenital Amaurosis. Invest Ophthalmol Vis Sci 2018; 59:85-93. [PMID: 29332120 PMCID: PMC5769497 DOI: 10.1167/iovs.17-22905] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose RPE65-associated Leber congenital amaurosis (RPE65-LCA) is a progressive severe retinal dystrophy with early profound dysfunction of rod photoreceptors followed by progressive cone photoreceptor degeneration. We aim to provide detailed information about how cone dysfunction affects color discrimination. Methods Seven adults (aged 16-21) with RPE65-LCA underwent monocular color discrimination assessment using the Trivector and Ellipse versions of three computerized tests: Cambridge Colour Test (CCT), low vision version of the Cambridge Colour Test (lvvCCT), and the Universal Colour Discrimination Test (UCDT). For comparison, subjects were also tested using the American Optical Hardy Rand Rittler (AO-HRR) plates. Each assessment was repeated three times. Results The Trivector version of the tests demonstrated that color discrimination along the tritan axis was undetectable in four subjects, and severely reduced in three subjects. These findings were confirmed by the Ellipse version of the tests. Color discrimination along the protan and deutan axes was evident but reduced in six of seven subjects. Four of seven subjects were unable to read any of the HRR plates. Conclusions The computerized color vision tests adopted in this study provide detailed information about color discrimination in adult RPE65-LCA patients. The condition is associated with severe impairment of color discrimination, particularly along the tritan axis indicating possible early involvement of S-cones, with additional protan and deutan loss to a lesser extent. This psychophysical assessment strategy is likely to be valuable in measuring the impact of therapeutic intervention on cone function.
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Affiliation(s)
- Neruban Kumaran
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | | | - Angelos Kalitzeos
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - Gary S Rubin
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - James W B Bainbridge
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,Moorfields Eye Hospital, London, United Kingdom
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14
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Abstract
INTRODUCTION Inherited retinal diseases are the leading cause of sight impairment in people of working age in England and Wales, and the second commonest in childhood. Gene therapy offers the potential for benefit. SOURCES OF DATA Pubmed and clinicaltrials.gov. AREAS OF AGREEMENT Gene therapy can improve vision in RPE65-associated Leber Congenital Amaurosis (RPE65-LCA). Potential benefit depends on efficient gene transfer and is limited by the extent of retinal degeneration. AREAS OF CONTROVERSY The magnitude of vision improvement from RPE65-LCA gene therapy is suboptimal, and its durability may be limited by progressive retinal degeneration. GROWING POINTS The safety and potential benefit of gene therapy for inherited and acquired retinal diseases is being explored in a rapidly expanding number of trials. AREAS TIMELY FOR DEVELOPING RESEARCH Developments in vector design and delivery will enable greater efficiency and safety of gene transfer. Optimization of trial design will accelerate reliable assessment of outcomes.
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Affiliation(s)
- Neruban Kumaran
- NIHR Biomedical Research Centre for Ophthalmology at Moofields Eye Hospital and UCL, 162 City Road, London, UK
| | - Michel Michaelides
- NIHR Biomedical Research Centre for Ophthalmology at Moofields Eye Hospital and UCL, 162 City Road, London, UK
| | - Alexander J Smith
- NIHR Biomedical Research Centre for Ophthalmology at Moofields Eye Hospital and UCL, 162 City Road, London, UK
| | - Robin R Ali
- NIHR Biomedical Research Centre for Ophthalmology at Moofields Eye Hospital and UCL, 162 City Road, London, UK
| | - James W B Bainbridge
- NIHR Biomedical Research Centre for Ophthalmology at Moofields Eye Hospital and UCL, 162 City Road, London, UK
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15
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Cristante E, Liyanage SE, Sampson RD, Kalargyrou A, De Rossi G, Rizzi M, Hoke J, Ribeiro J, Maswood RN, Duran Y, Matsuki T, Aghaizu ND, Luhmann UF, Smith AJ, Ali RR, Bainbridge JWB. Late neuroprogenitors contribute to normal retinal vascular development in a Hif2a-dependent manner. Development 2018; 145:dev.157511. [PMID: 29615467 DOI: 10.1242/dev.157511] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2017] [Accepted: 03/20/2018] [Indexed: 12/20/2022]
Abstract
In the adult central nervous system, endothelial and neuronal cells engage in tight cross-talk as key components of the so-called neurovascular unit. Impairment of this important relationship adversely affects tissue homeostasis, as observed in neurodegenerative conditions including Alzheimer's and Parkinson's disease. In development, the influence of neuroprogenitor cells on angiogenesis is poorly understood. Here, we show in mouse that these cells interact intimately with the growing retinal vascular network, and we identify a novel regulatory mechanism of vasculature development mediated by hypoxia-inducible factor 2a (Hif2a). By Cre-lox gene excision, we show that Hif2a in retinal neuroprogenitor cells upregulates the expression of the pro-angiogenic mediators vascular endothelial growth factor and erythropoietin, whereas it locally downregulates the angiogenesis inhibitor endostatin. Importantly, absence of Hif2a in retinal neuroprogenitor cells causes a marked reduction of proliferating endothelial cells at the angiogenic front. This results in delayed retinal vascular development, fewer major retinal vessels and reduced density of the peripheral deep retinal vascular plexus. Our findings demonstrate that retinal neuroprogenitor cells are a crucial component of the developing neurovascular unit.
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Affiliation(s)
- Enrico Cristante
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK .,NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, City Road, London EC1V 2PD, UK
| | - Sidath E Liyanage
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK.,NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, City Road, London EC1V 2PD, UK
| | - Robert D Sampson
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Giulia De Rossi
- Centre for Microvascular Research, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
| | - Matteo Rizzi
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK.,NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, City Road, London EC1V 2PD, UK
| | - Justin Hoke
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Joana Ribeiro
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Ryea N Maswood
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Yanai Duran
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Takaaki Matsuki
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Nozie D Aghaizu
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Ulrich F Luhmann
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK.,NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, City Road, London EC1V 2PD, UK
| | - Alexander J Smith
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Robin R Ali
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK.,NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, City Road, London EC1V 2PD, UK
| | - James W B Bainbridge
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK .,NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, City Road, London EC1V 2PD, UK
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16
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Lakowski J, Welby E, Budinger D, Di Marco F, Di Foggia V, Bainbridge JWB, Wallace K, Gamm DM, Ali RR, Sowden JC. Isolation of Human Photoreceptor Precursors via a Cell Surface Marker Panel from Stem Cell-Derived Retinal Organoids and Fetal Retinae. Stem Cells 2018; 36:709-722. [PMID: 29327488 PMCID: PMC5947711 DOI: 10.1002/stem.2775] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 12/01/2017] [Accepted: 12/14/2017] [Indexed: 12/16/2022]
Abstract
Loss of photoreceptor cells due to retinal degeneration is one of the main causes of blindness in the developed world. Although there is currently no effective treatment, cell replacement therapy using stem‐cell‐derived photoreceptor cells may be a feasible future treatment option. In order to ensure safety and efficacy of this approach, robust cell isolation and purification protocols must be developed. To this end, we previously developed a biomarker panel for the isolation of mouse photoreceptor precursors from the developing mouse retina and mouse embryonic stem cell cultures. In the current study we applied this approach to the human pluripotent stem cell (hPSC) system, and identified novel biomarker combinations that can be leveraged for the isolation of human photoreceptors. Human retinal samples and hPSC‐derived retinal organoid cultures were screened against 242 human monoclonal antibodies using a high through‐put flow cytometry approach. We identified 46 biomarkers with significant expression levels in the human retina and hPSC differentiation cultures. Human retinal cell samples, either from fetal tissue or derived from embryonic and induced pluripotent stem cell cultures, were fluorescence‐activated cell sorted (FACS) using selected candidate biomarkers that showed expression in discrete cell populations. Enrichment for photoreceptors and exclusion of mitotically active cells was demonstrated by immunocytochemical analysis with photoreceptor‐specific antibodies and Ki‐67. We established a biomarker combination, which enables the robust purification of viable human photoreceptors from both human retinae and hPSC‐derived organoid cultures. Stem Cells2018;36:709–722
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Affiliation(s)
- Jörn Lakowski
- Stem Cells and Regenerative Medicine Section, University College London, London, United Kingdom
| | - Emily Welby
- Stem Cells and Regenerative Medicine Section, University College London, London, United Kingdom.,NIHR Great Ormond Street Hospital Biomedical Research Centre, UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | - Dimitri Budinger
- Stem Cells and Regenerative Medicine Section, University College London, London, United Kingdom
| | - Fabiana Di Marco
- Stem Cells and Regenerative Medicine Section, University College London, London, United Kingdom
| | - Valentina Di Foggia
- Stem Cells and Regenerative Medicine Section, University College London, London, United Kingdom.,NIHR Great Ormond Street Hospital Biomedical Research Centre, UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
| | | | - Kyle Wallace
- Waisman Center, University of Wisconsin-Madison School of Medicine and Public Health, Waisman Center Rm T609, Madison, Wisconsin, USA
| | - David M Gamm
- Waisman Center, University of Wisconsin-Madison School of Medicine and Public Health, Waisman Center Rm T609, Madison, Wisconsin, USA.,Department of Ophthalmology and Visual Sciences and McPherson Eye Research Institute, University of Wisconsin-Madison School of Medicine and Public Health, Waisman Center Rm T609, Madison, Wisconsin, USA
| | - Robin R Ali
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
| | - Jane C Sowden
- Stem Cells and Regenerative Medicine Section, University College London, London, United Kingdom.,NIHR Great Ormond Street Hospital Biomedical Research Centre, UCL Great Ormond Street Institute of Child Health, University College London, London, United Kingdom
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17
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Waldron PV, Di Marco F, Kruczek K, Ribeiro J, Graca AB, Hippert C, Aghaizu ND, Kalargyrou AA, Barber AC, Grimaldi G, Duran Y, Blackford SJI, Kloc M, Goh D, Zabala Aldunate E, Sampson RD, Bainbridge JWB, Smith AJ, Gonzalez-Cordero A, Sowden JC, Ali RR, Pearson RA. Transplanted Donor- or Stem Cell-Derived Cone Photoreceptors Can Both Integrate and Undergo Material Transfer in an Environment-Dependent Manner. Stem Cell Reports 2018; 10:406-421. [PMID: 29307580 PMCID: PMC5830910 DOI: 10.1016/j.stemcr.2017.12.008] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 12/08/2017] [Accepted: 12/08/2017] [Indexed: 11/24/2022] Open
Abstract
Human vision relies heavily upon cone photoreceptors, and their loss results in permanent visual impairment. Transplantation of healthy photoreceptors can restore visual function in models of inherited blindness, a process previously understood to arise by donor cell integration within the host retina. However, we and others recently demonstrated that donor rod photoreceptors engage in material transfer with host photoreceptors, leading to the host cells acquiring proteins otherwise expressed only by donor cells. We sought to determine whether stem cell- and donor-derived cones undergo integration and/or material transfer. We find that material transfer accounts for a significant proportion of rescued cells following cone transplantation into non-degenerative hosts. Strikingly, however, substantial numbers of cones integrated into the Nrl-/- and Prph2rd2/rd2, but not Nrl-/-;RPE65R91W/R91W, murine models of retinal degeneration. This confirms the occurrence of photoreceptor integration in certain models of retinal degeneration and demonstrates the importance of the host environment in determining transplantation outcome.
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Affiliation(s)
- Paul V Waldron
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Fabiana Di Marco
- Stem Cells and Regenerative Medicine Section, UCL Great Ormond Street Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
| | - Kamil Kruczek
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Joana Ribeiro
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Anna B Graca
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Claire Hippert
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Nozie D Aghaizu
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Amanda C Barber
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Giulia Grimaldi
- Stem Cells and Regenerative Medicine Section, UCL Great Ormond Street Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
| | - Yanai Duran
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Magdalena Kloc
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Debbie Goh
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Eduardo Zabala Aldunate
- Stem Cells and Regenerative Medicine Section, UCL Great Ormond Street Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
| | - Robert D Sampson
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Alexander J Smith
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | | | - Jane C Sowden
- Stem Cells and Regenerative Medicine Section, UCL Great Ormond Street Institute of Child Health, University College London, 30 Guilford Street, London WC1N 1EH, UK
| | - Robin R Ali
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Rachael A Pearson
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK.
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18
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Gonzalez-Cordero A, Kruczek K, Naeem A, Fernando M, Kloc M, Ribeiro J, Goh D, Duran Y, Blackford SJI, Abelleira-Hervas L, Sampson RD, Shum IO, Branch MJ, Gardner PJ, Sowden JC, Bainbridge JWB, Smith AJ, West EL, Pearson RA, Ali RR. Recapitulation of Human Retinal Development from Human Pluripotent Stem Cells Generates Transplantable Populations of Cone Photoreceptors. Stem Cell Reports 2017; 9:820-837. [PMID: 28844659 PMCID: PMC5599247 DOI: 10.1016/j.stemcr.2017.07.022] [Citation(s) in RCA: 143] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 07/26/2017] [Accepted: 07/27/2017] [Indexed: 11/24/2022] Open
Abstract
Transplantation of rod photoreceptors, derived either from neonatal retinae or pluripotent stem cells (PSCs), can restore rod-mediated visual function in murine models of inherited blindness. However, humans depend more upon cone photoreceptors that are required for daylight, color, and high-acuity vision. Indeed, macular retinopathies involving loss of cones are leading causes of blindness. An essential step for developing stem cell-based therapies for maculopathies is the ability to generate transplantable human cones from renewable sources. Here, we report a modified 2D/3D protocol for generating hPSC-derived neural retinal vesicles with well-formed ONL-like structures containing cones and rods bearing inner segments and connecting cilia, nascent outer segments, and presynaptic structures. This differentiation system recapitulates human photoreceptor development, allowing the isolation and transplantation of a pure population of stage-matched cones. Purified human long/medium cones survive and become incorporated within the adult mouse retina, supporting the potential of photoreceptor transplantation for treating retinal degeneration. hPSC-derived photoreceptors express markers in a pattern similar to human development 2D/3D differentiation protocol generates sufficient cones for transplantation hPSC-derived cones incorporate into the adult retina following transplantation
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Affiliation(s)
- Anai Gonzalez-Cordero
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Kamil Kruczek
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Arifa Naeem
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Milan Fernando
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Magdalena Kloc
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Joana Ribeiro
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Debbie Goh
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Yanai Duran
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Samuel J I Blackford
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Laura Abelleira-Hervas
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Robert D Sampson
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Ian O Shum
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Matthew J Branch
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Peter J Gardner
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Jane C Sowden
- Stem Cells and Regenerative Medicine Section, UCL Great Ormond Street Institute of Child Health, University College London, London WC1N 1EH, UK
| | - James W B Bainbridge
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Alexander J Smith
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Emma L West
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Rachael A Pearson
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Robin R Ali
- Department of Genetics, University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, City Road, London EC1V 2PD, UK.
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19
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Georgiadis A, Duran Y, Ribeiro J, Abelleira-Hervas L, Robbie SJ, Sünkel-Laing B, Fourali S, Gonzalez-Cordero A, Cristante E, Michaelides M, Bainbridge JWB, Smith AJ, Ali RR. Development of an optimized AAV2/5 gene therapy vector for Leber congenital amaurosis owing to defects in RPE65. Gene Ther 2016; 23:857-862. [PMID: 27653967 PMCID: PMC5143366 DOI: 10.1038/gt.2016.66] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 08/18/2016] [Accepted: 08/26/2016] [Indexed: 12/02/2022]
Abstract
Leber congenital amaurosis is a group of inherited retinal dystrophies that cause severe sight impairment in childhood; RPE65-deficiency causes impaired rod photoreceptor function from birth and progressive impairment of cone photoreceptor function associated with retinal degeneration. In animal models of RPE65 deficiency, subretinal injection of recombinant adeno-associated virus (AAV) 2/2 vectors carrying RPE65 cDNA improves rod photoreceptor function, and intervention at an early stage of disease provides sustained benefit by protecting cone photoreceptors against retinal degeneration. In affected humans, administration of these vectors has resulted to date in relatively modest improvements in photoreceptor function, even when retinal degeneration is comparatively mild, and the duration of benefit is limited by progressive retinal degeneration. We conclude that the demand for RPE65 in humans is not fully met by current vectors, and predict that a more powerful vector will provide more durable benefit. With this aim we have modified the original AAV2/2 vector to generate AAV2/5-OPTIRPE65. The new configuration consists of an AAV vector serotype 5 carrying an optimized hRPE65 promoter and a codon-optimized hRPE65 gene. In mice, AAV2/5-OPTIRPE65 is at least 300-fold more potent than our original AAV2/2 vector.
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Affiliation(s)
- A Georgiadis
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - Y Duran
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - J Ribeiro
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - L Abelleira-Hervas
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - S J Robbie
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - B Sünkel-Laing
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - S Fourali
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - A Gonzalez-Cordero
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - E Cristante
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - M Michaelides
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK.,NIHR Biomedical Research Centre at Moorfields Eye Hospital, London EC1V 2PD, UK
| | - J W B Bainbridge
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK.,NIHR Biomedical Research Centre at Moorfields Eye Hospital, London EC1V 2PD, UK
| | - A J Smith
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - R R Ali
- Department of Genetics, UCL Institute of Ophthalmology, London EC1V 9EL, UK.,NIHR Biomedical Research Centre at Moorfields Eye Hospital, London EC1V 2PD, UK
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20
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Sim DA, Chu CJ, Selvam S, Powner MB, Liyanage S, Copland DA, Keane PA, Tufail A, Egan CA, Bainbridge JWB, Lee RW, Dick AD, Fruttiger M. A simple method for in vivo labelling of infiltrating leukocytes in the mouse retina using indocyanine green dye. Dis Model Mech 2015; 8:1479-87. [PMID: 26398933 PMCID: PMC4631782 DOI: 10.1242/dmm.019018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 08/09/2015] [Indexed: 01/20/2023] Open
Abstract
We have developed a method to label and image myeloid cells infiltrating the mouse retina and choroid in vivo, using a single depot injection of indocyanine green dye (ICG). This was demonstrated using the following ocular models of inflammation and angiogenesis: endotoxin-induced uveitis, experimental autoimmune uveoretinitis and laser-induced choroidal neovascularization model. A near-infrared scanning ophthalmoscope was used for in vivo imaging of the eye, and flow cytometry was used on blood and spleen to assess the number and phenotype of labelled cells. ICG was administered 72 h before the induction of inflammation to ensure clearance from the systemic circulation. We found that in vivo intravenous administration failed to label any leukocytes, whereas depot injection, either intraperitoneal or subcutaneous, was successful in labelling leukocytes infiltrating into the retina. Progression of inflammation in the retina could be traced over a period of 14 days following a single depot injection of ICG. Additionally, bright-field microscopy, spectrophotometry and flow cytometric analysis suggest that the predominant population of cells stained by ICG are circulating myeloid cells. The translation of this approach into clinical practice would enable visualization of immune cells in situ. This will not only provide a greater understanding of pathogenesis, monitoring and assessment of therapy in many human ocular diseases but might also open the ability to image immunity live for neurodegenerative disorders, cardiovascular disease and systemic immune-mediated disorders. Summary: We show here that peripheral leukocytes can be labelled with ICG in vivo and then directly imaged as they invade the retina after inflammatory stimuli.
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Affiliation(s)
- Dawn A Sim
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK University College London, Institute of Ophthalmology, London EC1V 9EL, UK
| | - Colin J Chu
- University College London, Institute of Ophthalmology, London EC1V 9EL, UK Academic Unit of Ophthalmology, School of Clinical Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - Senthil Selvam
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK University College London, Institute of Ophthalmology, London EC1V 9EL, UK
| | - Michael B Powner
- University College London, Institute of Ophthalmology, London EC1V 9EL, UK
| | - Sidath Liyanage
- University College London, Institute of Ophthalmology, London EC1V 9EL, UK
| | - David A Copland
- Academic Unit of Ophthalmology, School of Clinical Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - Pearse A Keane
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK University College London, Institute of Ophthalmology, London EC1V 9EL, UK
| | - Adnan Tufail
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK University College London, Institute of Ophthalmology, London EC1V 9EL, UK
| | - Catherine A Egan
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
| | - James W B Bainbridge
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK University College London, Institute of Ophthalmology, London EC1V 9EL, UK
| | - Richard W Lee
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK Academic Unit of Ophthalmology, School of Clinical Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - Andrew D Dick
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK Academic Unit of Ophthalmology, School of Clinical Sciences, University of Bristol, Bristol BS8 1TD, UK
| | - Marcus Fruttiger
- University College London, Institute of Ophthalmology, London EC1V 9EL, UK
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21
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Herrmann P, Cowing JA, Cristante E, Liyanage SE, Ribeiro J, Duran Y, Abelleira Hervas L, Carvalho LS, Bainbridge JWB, Luhmann UFO, Ali RR. Cd59a deficiency in mice leads to preferential innate immune activation in the retinal pigment epithelium-choroid with age. Neurobiol Aging 2015; 36:2637-48. [PMID: 26234657 DOI: 10.1016/j.neurobiolaging.2015.05.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 04/30/2015] [Accepted: 05/29/2015] [Indexed: 11/29/2022]
Abstract
Dysregulation of the complement system has been implicated in the pathogenesis of age-related macular degeneration. To investigate consequences of altered complement regulation in the eye with age, we examined Cd59a complement regulator deficient (Cd59a(-/-)) mice between 4 and 15 months. In vivo imaging revealed an increased age-related accumulation of autofluorescent spots in Cd59a(-/-) mice, a feature that reflects accumulation of subretinal macrophages and/or microglia. Despite this activation of myeloid cells in the eye, Cd59a(-/-) mice showed normal retinal histology and function as well as normal choroidal microvasculature. With age, they revealed increased expression of activators of the alternative complement pathway (C3, Cfb, Cfd), in particular in the retinal pigment epithelium (RPE)-choroid but less in the retina. This molecular response was not altered by moderately-enhanced light exposure. Cd59a deficiency therefore leads to a preferential age-related dysregulation of the complement system in the RPE-choroid, that alone or in combination with light as a trigger, is not sufficient to cause choroidal vascular changes or retinal degeneration and dysfunction. This data emphasizes the particular vulnerability of the RPE-choroidal complex to dysregulation of the alternative complement pathway during aging.
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Affiliation(s)
- Philipp Herrmann
- Department of Genetics, UCL Institute of Ophthalmology, London, UK
| | - Jill A Cowing
- Department of Genetics, UCL Institute of Ophthalmology, London, UK
| | - Enrico Cristante
- Department of Genetics, UCL Institute of Ophthalmology, London, UK
| | | | - Joana Ribeiro
- Department of Genetics, UCL Institute of Ophthalmology, London, UK
| | - Yanai Duran
- Department of Genetics, UCL Institute of Ophthalmology, London, UK
| | | | - Livia S Carvalho
- Department of Genetics, UCL Institute of Ophthalmology, London, UK
| | - James W B Bainbridge
- Department of Genetics, UCL Institute of Ophthalmology, London, UK; NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital, London, UK
| | | | - Robin R Ali
- Department of Genetics, UCL Institute of Ophthalmology, London, UK; NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital, London, UK
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22
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Lakowski J, Gonzalez-Cordero A, West EL, Han YT, Welby E, Naeem A, Blackford SJI, Bainbridge JWB, Pearson RA, Ali RR, Sowden JC. Transplantation of Photoreceptor Precursors Isolated via a Cell Surface Biomarker Panel From Embryonic Stem Cell-Derived Self-Forming Retina. Stem Cells 2015; 33:2469-82. [PMID: 25982268 PMCID: PMC4862023 DOI: 10.1002/stem.2051] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 03/21/2015] [Indexed: 10/25/2022]
Abstract
Loss of photoreceptors due to retinal degeneration is a major cause of untreatable blindness. Cell replacement therapy, using pluripotent stem cell-derived photoreceptor cells, may be a feasible future treatment. Achieving safe and effective cell replacement is critically dependent on the stringent selection and purification of optimal cells for transplantation. Previously, we demonstrated effective transplantation of post-mitotic photoreceptor precursor cells labelled by fluorescent reporter genes. As genetically labelled cells are not desirable for therapy, here we developed a surface biomarker cell selection strategy for application to complex pluripotent stem cell differentiation cultures. We show that a five cell surface biomarker panel CD73(+)CD24(+)CD133(+)CD47(+)CD15(-) facilitates the isolation of photoreceptor precursors from three-dimensional self-forming retina differentiated from mouse embryonic stem cells. Importantly, stem cell-derived cells isolated using the biomarker panel successfully integrate and mature into new rod photoreceptors in the adult mouse retinae after subretinal transplantation. Conversely, unsorted or negatively selected cells do not give rise to newly integrated rods after transplantation. The biomarker panel also removes detrimental proliferating cells prior to transplantation. Notably, we demonstrate how expression of the biomarker panel is conserved in the human retina and propose that a similar selection strategy will facilitate isolation of human transplantation-competent cells for therapeutic application.
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Affiliation(s)
- Jorn Lakowski
- Stem Cells and Regenerative Medicine Section, UCL Institute of Child Health, University College London, London, United Kingdom
| | | | - Emma L West
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
| | - Ya-Ting Han
- Stem Cells and Regenerative Medicine Section, UCL Institute of Child Health, University College London, London, United Kingdom
| | - Emily Welby
- Stem Cells and Regenerative Medicine Section, UCL Institute of Child Health, University College London, London, United Kingdom
| | - Arifa Naeem
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
| | | | | | - Rachael A Pearson
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
| | - Robin R Ali
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
| | - Jane C Sowden
- Stem Cells and Regenerative Medicine Section, UCL Institute of Child Health, University College London, London, United Kingdom
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23
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Bainbridge JWB, Mehat MS, Sundaram V, Robbie SJ, Barker SE, Ripamonti C, Georgiadis A, Mowat FM, Beattie SG, Gardner PJ, Feathers KL, Luong VA, Yzer S, Balaggan K, Viswanathan A, de Ravel TJL, Casteels I, Holder GE, Tyler N, Fitzke FW, Weleber RG, Nardini M, Moore AT, Thompson DA, Petersen-Jones SM, Michaelides M, van den Born LI, Stockman A, Smith AJ, Rubin G, Ali RR. Long-term effect of gene therapy on Leber's congenital amaurosis. N Engl J Med 2015; 372:1887-97. [PMID: 25938638 PMCID: PMC4497809 DOI: 10.1056/nejmoa1414221] [Citation(s) in RCA: 525] [Impact Index Per Article: 58.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Mutations in RPE65 cause Leber's congenital amaurosis, a progressive retinal degenerative disease that severely impairs sight in children. Gene therapy can result in modest improvements in night vision, but knowledge of its efficacy in humans is limited. METHODS We performed a phase 1-2 open-label trial involving 12 participants to evaluate the safety and efficacy of gene therapy with a recombinant adeno-associated virus 2/2 (rAAV2/2) vector carrying the RPE65 complementary DNA, and measured visual function over the course of 3 years. Four participants were administered a lower dose of the vector, and 8 were administered a higher dose. In a parallel study in dogs, we investigated the relationship among vector dose, visual function, and electroretinography (ERG) findings. RESULTS Improvements in retinal sensitivity were evident, to varying extents, in six participants for up to 3 years, peaking at 6 to 12 months after treatment and then declining. No associated improvement in retinal function was detected by means of ERG. Three participants had intraocular inflammation, and two had clinically significant deterioration of visual acuity. The reduction in central retinal thickness varied among participants. In dogs, RPE65 gene therapy with the same vector at lower doses improved vision-guided behavior, but only higher doses resulted in improvements in retinal function that were detectable with the use of ERG. CONCLUSIONS Gene therapy with rAAV2/2 RPE65 vector improved retinal sensitivity, albeit modestly and temporarily. Comparison with the results obtained in the dog model indicates that there is a species difference in the amount of RPE65 required to drive the visual cycle and that the demand for RPE65 in affected persons was not met to the extent required for a durable, robust effect. (Funded by the National Institute for Health Research and others; ClinicalTrials.gov number, NCT00643747.).
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Affiliation(s)
- James W B Bainbridge
- From the UCL (University College London) Institute of Ophthalmology (J.W.B.B., M.S.M., V.S., S.J.R., S.E.B., C.R., A.G., F.M.M., S.G.B., P.J.G., V.A.L., K.B., A.V., G.E.H., F.W.F., M.N., A.T.M., M.M., A.S., A.J.S., G.R., R.R.A.) and the Department of Civil, Environmental, and Geomatic Engineering (N.T.), UCL, and Moorfields Eye Hospital (J.W.B.B., M.S.M., V.S., S.J.R., A.G., K.B., G.H., A.M., M.M.), London, and the Department of Psychology, Durham University, Durham (M.N.) - all in the United Kingdom; the College of Veterinary Medicine, Michigan State University, East Lansing (F.M.M., S.M.P.-J.), and the Kellogg Eye Center, University of Michigan Medical School, Ann Arbor (K.L.F., D.A.T., R.R.A.); the Center for Human Genetics, KU Leuven (T.J.L.R.), and the Department of Ophthalmology, UZ Leuven, Campus Sint-Rafaël (I.C.) - both in Leuven, Belgium; Rotterdam Eye Hospital, Rotterdam, the Netherlands (S.Y., L.I.B.); and the Oregon Retinal Degeneration Center, Ophthalmic Genetics Service, Casey Eye Institute, Oregon Health and Science University, Portland (R.G.W.)
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24
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Luhmann UFO, Carvalho LS, Holthaus SMK, Cowing JA, Greenaway S, Chu CJ, Herrmann P, Smith AJ, Munro PMG, Potter P, Bainbridge JWB, Ali RR. The severity of retinal pathology in homozygous Crb1rd8/rd8 mice is dependent on additional genetic factors. Hum Mol Genet 2014; 24:128-41. [PMID: 25147295 PMCID: PMC4262495 DOI: 10.1093/hmg/ddu424] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
Abstract
Understanding phenotype–genotype correlations in retinal degeneration is a major challenge. Mutations in CRB1 lead to a spectrum of autosomal recessive retinal dystrophies with variable phenotypes suggesting the influence of modifying factors. To establish the contribution of the genetic background to phenotypic variability associated with the Crb1rd8/rd8 mutation, we compared the retinal pathology of Crb1rd8/rd8/J inbred mice with that of two Crb1rd8/rd8 lines backcrossed with C57BL/6JOlaHsd mice. Topical endoscopic fundal imaging and scanning laser ophthalmoscopy fundus images of all three Crb1rd8/rd8 lines showed a significant increase in the number of inferior retinal lesions that was strikingly variable between the lines. Optical coherence tomography, semithin, ultrastructural morphology and assessment of inflammatory and vascular marker by immunohistochemistry and quantitative reverse transcriptase-polymerase chain reaction revealed that the lesions were associated with photoreceptor death, Müller and microglia activation and telangiectasia-like vascular remodelling—features that were stable in the inbred, variable in the second, but virtually absent in the third Crb1rd8/rd8 line, even at 12 months of age. This suggests that the Crb1rd8/rd8 mutation is necessary, but not sufficient for the development of these degenerative features. By whole-genome SNP analysis of the genotype–phenotype correlation, a candidate region on chromosome 15 was identified. This may carry one or more genetic modifiers for the manifestation of the retinal pathology associated with mutations in Crb1. This study also provides insight into the nature of the retinal vascular lesions that likely represent a clinical correlate for the formation of retinal telangiectasia or Coats-like vasculopathy in patients with CRB1 mutations that are thought to depend on such genetic modifiers.
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Affiliation(s)
| | | | - Sophia-Martha Kleine Holthaus
- Department of Genetics and MRC Laboratory for Molecular Cell Biology, University College London, London WC1E 6BT, UK
| | | | - Simon Greenaway
- Imaging Unit, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | | | | | | | - Peter M G Munro
- Imaging Unit, UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - Paul Potter
- Mammalian Genetics Unit, MRC Harwell, Oxfordshire OX11 ORD, UK and
| | - James W B Bainbridge
- Department of Genetics and NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London EC1V 2PD, UK
| | - Robin R Ali
- Department of Genetics and NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London EC1V 2PD, UK
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Annear MJ, Mowat FM, Bartoe JT, Querubin J, Azam SA, Basche M, Curran PG, Smith AJ, Bainbridge JWB, Ali RR, Petersen-Jones SM. Successful gene therapy in older Rpe65-deficient dogs following subretinal injection of an adeno-associated vector expressing RPE65. Hum Gene Ther 2014; 24:883-93. [PMID: 24028205 DOI: 10.1089/hum.2013.146] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Young Rpe65-deficient dogs have been used as a model for human RPE65 Leber congenital amaurosis (RPE65-LCA) in proof-of-concept trials of recombinant adeno-associated virus (rAAV) gene therapy. However, there are relatively few reports of the outcome of rAAV gene therapy in Rpe65-deficient dogs older than 2 years of age. The purpose of this study was to investigate the success of this therapy in older Rpe65-deficient dogs. Thirteen eyes were treated in dogs between 2 and 6 years old. An rAAV2 vector expressing the human RPE65 cDNA driven by the human RPE65 promoter was delivered by subretinal injection. Twelve of the 13 eyes had improved retinal function as assessed by electroretinography, and all showed improvement in vision at low lighting intensities. Histologic examination of five of the eyes was performed but found no correlation between electroretinogram (ERG) rescue and numbers of remaining photoreceptors. We conclude that functional rescue is still possible in older dogs and that the use of older Rpe65-deficient dogs, rather than young Rpe65-deficient dogs that have very little loss of photoreceptors, more accurately models the situation when treating human RPE65-LCA patients.
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Affiliation(s)
- Matthew J Annear
- 1 Department of Small Animal Clinical Sciences, Michigan State University , East Lansing, MI 48824
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Wang X, Abraham S, McKenzie JAG, Jeffs N, Swire M, Tripathi VB, Luhmann UFO, Lange CAK, Zhai Z, Arthur HM, Bainbridge JWB, Moss SE, Greenwood J. Erratum: Corrigendum: LRG1 promotes angiogenesis by modulating endothelial TGF-β signalling. Nature 2013. [DOI: 10.1038/nature12641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Gonzalez-Cordero A, West EL, Pearson RA, Duran Y, Carvalho LS, Chu CJ, Naeem A, Blackford SJI, Georgiadis A, Lakowski J, Hubank M, Smith AJ, Bainbridge JWB, Sowden JC, Ali RR. Photoreceptor precursors derived from three-dimensional embryonic stem cell cultures integrate and mature within adult degenerate retina. Nat Biotechnol 2013. [PMID: 23873086 DOI: 10.1038/nbt.2643]] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Irreversible blindness caused by loss of photoreceptors may be amenable to cell therapy. We previously demonstrated retinal repair and restoration of vision through transplantation of photoreceptor precursors obtained from postnatal retinas into visually impaired adult mice. Considerable progress has been made in differentiating embryonic stem cells (ESCs) in vitro toward photoreceptor lineages. However, the capability of ESC-derived photoreceptors to integrate after transplantation has not been demonstrated unequivocally. Here, to isolate photoreceptor precursors fit for transplantation, we adapted a recently reported three-dimensional (3D) differentiation protocol that generates neuroretina from mouse ESCs. We show that rod precursors derived by this protocol and selected via a GFP reporter under the control of a Rhodopsin promoter integrate within degenerate retinas of adult mice and mature into outer segment-bearing photoreceptors. Notably, ESC-derived precursors at a developmental stage similar to postnatal days 4-8 integrate more efficiently compared with cells at other stages. This study shows conclusively that ESCs can provide a source of photoreceptors for retinal cell transplantation.
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Affiliation(s)
- Anai Gonzalez-Cordero
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Emma L West
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Rachael A Pearson
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Yanai Duran
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Livia S Carvalho
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Colin J Chu
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Arifa Naeem
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Samuel J I Blackford
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Anastasios Georgiadis
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Jorn Lakowski
- Developmental Biology Unit, University College London, 30 Guilford Street, London, WC1N 1EH UK
| | - Mike Hubank
- UCL Genomics, University College London, 30 Guilford Street, London, WC1N 1EH UK
| | - Alexander J Smith
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - James W B Bainbridge
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Jane C Sowden
- Developmental Biology Unit, University College London, 30 Guilford Street, London, WC1N 1EH UK
| | - Robin R Ali
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK.,Molecular Immunology Unit, Institute of Child Health, University College London, 30 Guilford Street, London, WC1N 1EH UK
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Gonzalez-Cordero A, West EL, Pearson RA, Duran Y, Carvalho LS, Chu CJ, Naeem A, Blackford SJI, Georgiadis A, Lakowski J, Hubank M, Smith AJ, Bainbridge JWB, Sowden JC, Ali RR. Photoreceptor precursors derived from three-dimensional embryonic stem cell cultures integrate and mature within adult degenerate retina. Nat Biotechnol 2013. [PMID: 23873086 DOI: 10.1038/nbt.2643].] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Irreversible blindness caused by loss of photoreceptors may be amenable to cell therapy. We previously demonstrated retinal repair and restoration of vision through transplantation of photoreceptor precursors obtained from postnatal retinas into visually impaired adult mice. Considerable progress has been made in differentiating embryonic stem cells (ESCs) in vitro toward photoreceptor lineages. However, the capability of ESC-derived photoreceptors to integrate after transplantation has not been demonstrated unequivocally. Here, to isolate photoreceptor precursors fit for transplantation, we adapted a recently reported three-dimensional (3D) differentiation protocol that generates neuroretina from mouse ESCs. We show that rod precursors derived by this protocol and selected via a GFP reporter under the control of a Rhodopsin promoter integrate within degenerate retinas of adult mice and mature into outer segment-bearing photoreceptors. Notably, ESC-derived precursors at a developmental stage similar to postnatal days 4-8 integrate more efficiently compared with cells at other stages. This study shows conclusively that ESCs can provide a source of photoreceptors for retinal cell transplantation.
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Affiliation(s)
- Anai Gonzalez-Cordero
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Emma L West
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Rachael A Pearson
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Yanai Duran
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Livia S Carvalho
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Colin J Chu
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Arifa Naeem
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Samuel J I Blackford
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Anastasios Georgiadis
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Jorn Lakowski
- Developmental Biology Unit, University College London, 30 Guilford Street, London, WC1N 1EH UK
| | - Mike Hubank
- UCL Genomics, University College London, 30 Guilford Street, London, WC1N 1EH UK
| | - Alexander J Smith
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - James W B Bainbridge
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Jane C Sowden
- Developmental Biology Unit, University College London, 30 Guilford Street, London, WC1N 1EH UK
| | - Robin R Ali
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK.,Molecular Immunology Unit, Institute of Child Health, University College London, 30 Guilford Street, London, WC1N 1EH UK
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Chu CJ, Herrmann P, Carvalho LS, Liyanage SE, Bainbridge JWB, Ali RR, Dick AD, Luhmann UFO. Assessment and in vivo scoring of murine experimental autoimmune uveoretinitis using optical coherence tomography. PLoS One 2013; 8:e63002. [PMID: 23690973 PMCID: PMC3653962 DOI: 10.1371/journal.pone.0063002] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Accepted: 03/27/2013] [Indexed: 12/02/2022] Open
Abstract
Despite advances in clinical imaging and grading our understanding of retinal immune responses and their morphological correlates in experimental autoimmune uveoretinitis (EAU), has been hindered by the requirement for post-mortem histology. To date, monitoring changes occurring during EAU disease progression and evaluating the effect of therapeutic intervention in real time has not been possible. We wanted to establish whether optical coherence tomography (OCT) could detect intraretinal changes during inflammation and to determine its utility as a tool for accurate scoring of EAU. EAU was induced in C57BL/6J mice and animals evaluated after 15, 26, 36 and 60 days. At each time-point, contemporaneous Spectralis-OCT scanning, topical endoscopic fundal imaging (TEFI), fundus fluorescein angiography (FFA) and CD45-immunolabelled histology were performed. OCT features were further characterised on retinal flat-mounts using immunohistochemistry and 3D reconstruction. Optic disc swelling and vitreous opacities detected by OCT corresponded to CD45+ cell infiltration on histology. Vasculitis identified by FFA and OCT matched perivascular myeloid and T-cell infiltrates and could be differentiated from unaffected vessels. Evolution of these changes could be followed over time in the same eye. Retinal folds were visible and found to encapsulate mixed populations of activated myeloid cells, T-cells and microglia. Using these features, an OCT-based EAU scoring system was developed, with significant correlation to validated histological (Pearson r2 = 0.6392, P<0.0001, n = 31 eyes) and TEFI based scoring systems (r2 = 0.6784, P<0.0001). OCT distinguishes the fundamental features of murine EAU in vivo, permits dynamic assessment of intraretinal changes and can be used to score disease severity. As a result, it allows tissue synchronisation with subsequent cellular and functional assessment and greater efficiency of animal usage. By relating OCT signals with immunohistochemistry in EAU, our findings offer the opportunity to inform the interpretation of OCT changes in human uveitis.
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Affiliation(s)
- Colin J. Chu
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
| | - Philipp Herrmann
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
| | - Livia S. Carvalho
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
| | - Sidath E. Liyanage
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
| | - James W. B. Bainbridge
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital, London, United Kingdom
| | - Robin R. Ali
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital, London, United Kingdom
| | - Andrew D. Dick
- NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital, London, United Kingdom
- Unit of Ophthalmology, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
- * E-mail: (UFL); (ADD)
| | - Ulrich F. O. Luhmann
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom
- * E-mail: (UFL); (ADD)
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Luhmann UFO, Carvalho LS, Robbie SJ, Cowing JA, Duran Y, Munro PMG, Bainbridge JWB, Ali RR. Ccl2, Cx3cr1 and Ccl2/Cx3cr1 chemokine deficiencies are not sufficient to cause age-related retinal degeneration. Exp Eye Res 2012; 107:80-7. [PMID: 23232206 PMCID: PMC3562441 DOI: 10.1016/j.exer.2012.11.015] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 11/22/2012] [Accepted: 11/26/2012] [Indexed: 11/28/2022]
Abstract
Monocytes, macrophages, dendritic cells and microglia play critical roles in the local immune response to acute and chronic tissue injury and have been implicated in the pathogenesis of age-related macular degeneration. Defects in Ccl2-Ccr2 and Cx3cl1-Cx3cr1 chemokine signalling cause enhanced accumulation of bloated subretinal microglia/macrophages in senescent mice and this phenomenon is reported to result in the acceleration of age-related retinal degeneration. The purpose of this study was to determine whether defects in CCL2-CCR2 and CX3CL1-CX3CR1 signalling pathways, alone or in combination, cause age-dependent retinal degeneration. We tested whether three chemokine knockout mouse lines, Ccl2(-/-), Cx3cr1(-/-) and Ccl2(-/-)/Cx3cr1(-/-), in comparison to age-matched C57Bl/6 control mice show differences in subretinal macrophage accumulation and loss of adjacent photoreceptor cells at 12-14 months of age. All mouse lines are derived from common parental strains and do not carry the homozygous rd8 mutation in the Crb1 gene that has been a major confounding factor in previous reports. We quantified subretinal macrophages by counting autofluorescent lesions in fundus images obtained by scanning laser ophthalmoscopy (AF-SLO) and by immunohistochemistry for Iba1 positive cells. The accumulation of subretinal macrophages was enhanced in Ccl2(-/-), but not in Cx3cr1(-/-) or Ccl2(-/-)/Cx3cr1(-/-) mice. We identified no evidence of retinal degeneration in any of these mouse lines by TUNEL staining or semithin histology. In conclusion, CCL2-CCR2 and/or CX3CL1-CX3CR1 signalling defects may differentially affect the trafficking of microglia and macrophages in the retina during ageing, but do not appear to cause age-related retinal degeneration in mice.
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Affiliation(s)
- Ulrich F O Luhmann
- Department of Genetics, UCL Institute of Ophthalmology, 11-43 Bath Street, EC1V9EL London, United Kingdom.
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Mowat FM, Breuwer AR, Bartoe JT, Annear MJ, Zhang Z, Smith AJ, Bainbridge JWB, Petersen-Jones SM, Ali RR. RPE65 gene therapy slows cone loss in Rpe65-deficient dogs. Gene Ther 2012; 20:545-55. [PMID: 22951453 DOI: 10.1038/gt.2012.63] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recent clinical trials of retinal pigment epithelium gene (RPE65) supplementation therapy in Leber congenital amaurosis type 2 patients have demonstrated improvements in rod and cone function, but it may be some years before the effects of therapy on photoreceptor survival become apparent. The Rpe65-deficient dog is a very useful pre-clinical model in which to test efficacy of therapies, because the dog has a retina with a high degree of similarity to that of humans. In this study, we evaluated the effect of RPE65 gene therapy on photoreceptor survival in order to predict the potential benefit and limitations of therapy in patients. We examined the retinas of Rpe65-deficient dogs after RPE65 gene therapy to evaluate the preservation of rods and cone photoreceptor subtypes. We found that gene therapy preserves both rods and cones. While the moderate loss of rods in the Rpe65-deficient dog retina is slowed by gene therapy, S-cones are lost extensively and gene therapy can prevent that loss, although only within the treated area. Although LM-cones are not lost extensively, cone opsin mislocalization indicates that they are stressed, and this can be partially reversed by gene therapy. Our results suggest that gene therapy may be able to slow cone degeneration in patients if intervention is sufficiently early and also that it is probably important to treat the macula in order to preserve central function.
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Affiliation(s)
- F M Mowat
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48824, USA
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Lange CAK, Luhmann UFO, Mowat FM, Georgiadis A, West EL, Abrahams S, Sayed H, Powner MB, Fruttiger M, Smith AJ, Sowden JC, Maxwell PH, Ali RR, Bainbridge JWB. Von Hippel-Lindau protein in the RPE is essential for normal ocular growth and vascular development. Development 2012; 139:2340-50. [PMID: 22627278 DOI: 10.1242/dev.070813] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Molecular oxygen is essential for the development, growth and survival of multicellular organisms. Hypoxic microenvironments and oxygen gradients are generated physiologically during embryogenesis and organogenesis. In the eye, oxygen plays a crucial role in both physiological vascular development and common blinding diseases. The retinal pigment epithelium (RPE) is a monolayer of cells essential for normal ocular development and in the mature retina provides support for overlying photoreceptors and their vascular supply. Hypoxia at the level of the RPE is closely implicated in pathogenesis of age-related macular degeneration. Adaptive tissue responses to hypoxia are orchestrated by sophisticated oxygen sensing mechanisms. In particular, the von Hippel-Lindau tumour suppressor protein (pVhl) controls hypoxia-inducible transcription factor (HIF)-mediated adaptation. However, the role of Vhl/Hif1a in the RPE in the development of the eye and its vasculature is unknown. In this study we explored the function of Vhl and Hif1a in the developing RPE using a tissue-specific conditional-knockout approach. We found that deletion of Vhl in the RPE results in RPE apoptosis, aniridia and microphthalmia. Increased levels of Hif1a, Hif2a, Epo and Vegf are associated with a highly disorganised retinal vasculature, chorioretinal anastomoses and the persistence of embryonic vascular structures into adulthood. Additional inactivation of Hif1a in the RPE rescues the RPE morphology, aniridia, microphthalmia and anterior vasoproliferation, but does not rescue retinal vasoproliferation. These data demonstrate that Vhl-dependent regulation of Hif1a in the RPE is essential for normal RPE and iris development, ocular growth and vascular development in the anterior chamber, whereas Vhl-dependent regulation of other downstream pathways is crucial for normal development and maintenance of the retinal vasculature.
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Affiliation(s)
- Clemens A K Lange
- Department of Genetics, Institute of Ophthalmology, NIHR Biomedical Research Centre for Ophthalmology, University College London, London EC1V 9EL, UK
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Mowat FM, Gonzalez F, Luhmann UFO, Lange CA, Duran Y, Smith AJ, Maxwell PH, Ali RR, Bainbridge JWB. Endogenous erythropoietin protects neuroretinal function in ischemic retinopathy. Am J Pathol 2012; 180:1726-39. [PMID: 22342523 DOI: 10.1016/j.ajpath.2011.12.033] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 11/14/2011] [Accepted: 12/08/2011] [Indexed: 01/12/2023]
Abstract
Because retinal ischemia is a common cause of vision loss, we sought to determine the effects of ischemia on neuroretinal function and survival in murine oxygen-induced retinopathy (OIR) and to define the role of endogenous erythropoietin (EPO) in this model. OIR is a reproducible model of ischemia-induced retinal neovascularization; it is used commonly to develop antiangiogenic strategies. We investigated the effects of ischemia in murine OIR on retinal function and neurodegeneration by electroretinography and detailed morphology. OIR was associated with significant neuroretinal dysfunction, with reduced photopic and scotopic ERG responses and reduced b-wave/a-wave ratios consistent with specific inner-retinal dysfunction. OIR resulted in significantly increased apoptosis and atrophy of the inner retina in areas of ischemia. EPO deficiency in heterozygous Epo-Tag transgenic mice was associated with more profound retinal dysfunction after OIR, indicated by a significantly greater suppression of ERG amplitudes, but had no measurable effect on the extent of retinal ischemia, preretinal neovascularization, or neuroretinal degeneration in OIR. Systemic administration of recombinant EPO protected EPO-deficient mice against this additional suppression, but EPO supplementation in wild-type animals with OIR did not rescue neuroretinal dysfunction or degeneration. Murine OIR offers a valuable model of ischemic neuroretinal dysfunction and degeneration in which to investigate adaptive tissue responses and evaluate novel therapeutic approaches. Endogenous EPO can protect neuroretinal function in ischemic retinopathy.
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Affiliation(s)
- Freya M Mowat
- Department of Genetics, University College London Institute of Ophthalmology, London, United Kingdom
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Lange CAK, Stavrakas P, Luhmann UFO, de Silva DJ, Ali RR, Gregor ZJ, Bainbridge JWB. Intraocular oxygen distribution in advanced proliferative diabetic retinopathy. Am J Ophthalmol 2011; 152:406-412.e3. [PMID: 21723532 DOI: 10.1016/j.ajo.2011.02.014] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2010] [Revised: 02/18/2011] [Accepted: 02/20/2011] [Indexed: 12/17/2022]
Abstract
PURPOSE To determine the preretinal distribution of oxygen in advanced proliferative diabetic retinopathy, and to investigate the relationship between intraocular oxygen tensions and vitreous cytokine concentrations. DESIGN Comparative cross-sectional study. METHODS Oxygen levels were measured at sites in the vitreous and at the inner retinal surface using an optical oxygen sensor in 14 control subjects and in 14 subjects with advanced proliferative diabetic retinopathy who had developed tractional retinal detachments despite previous panretinal photocoagulation. The vitreous and plasma concentrations of 42 cytokines were measured using multiplex cytokine arrays and their correlation with intraocular oxygen tension was investigated. RESULTS The mean oxygen tension in the mid-vitreous in diabetic retinopathy was 46% lower than that in control subjects (P = .017). However, the mean preretinal oxygen tension at the posterior pole in diabetic retinopathy was 37% higher than in controls (P = .039). We measured significant alterations in the vitreous concentrations of 9 cytokines-eotaxin, Flt-3 ligand, growth-related oncogene (GRO), interleukin (IL)-6, IL-8, IL-9, IFN-inducible protein-10 (IP-10), macrophage-derived cytokine (MDC), and vascular endothelial growth factor (VEGF)-in advanced proliferative diabetic retinopathy, and found that oxygen tension at the posterior pole was directly correlated with vitreous VEGF concentration. CONCLUSION We identified significant intraocular oxygen gradients in proliferative diabetic retinopathy. Our findings are consistent with the hypothesis that VEGF induces the development of neovascular complexes in the posterior retina that are richly perfused but nonetheless fail to redress hypoxia in the mid-vitreous. Upregulation of vitreous VEGF may be a consequence of retinal hypoxia at unidentified sites or of chronic inflammatory processes in advanced proliferative diabetic retinopathy.
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Affiliation(s)
- Clemens A K Lange
- University College London, Institute of Ophthalmology and Moorfields Eye Hospital, National Institute for Health Research and Biomedical Research Centre, London, United Kingdom; University Eye Hospital Freiburg, Albert-Ludwigs-University, Freiburg, Germany; Vitreoretinal Service, Moorfields Eye Hospital, London, United Kingdom
| | | | - Ulrich F O Luhmann
- University College London, Institute of Ophthalmology and Moorfields Eye Hospital, National Institute for Health Research and Biomedical Research Centre, London, United Kingdom
| | | | - Robin R Ali
- University College London, Institute of Ophthalmology and Moorfields Eye Hospital, National Institute for Health Research and Biomedical Research Centre, London, United Kingdom
| | - Zdenek J Gregor
- Vitreoretinal Service, Moorfields Eye Hospital, London, United Kingdom
| | - James W B Bainbridge
- University College London, Institute of Ophthalmology and Moorfields Eye Hospital, National Institute for Health Research and Biomedical Research Centre, London, United Kingdom; Vitreoretinal Service, Moorfields Eye Hospital, London, United Kingdom.
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Mihelec M, Pearson RA, Robbie SJ, Buch PK, Azam SA, Bainbridge JWB, Smith AJ, Ali RR. Long-term preservation of cones and improvement in visual function following gene therapy in a mouse model of leber congenital amaurosis caused by guanylate cyclase-1 deficiency. Hum Gene Ther 2011; 22:1179-90. [PMID: 21671801 DOI: 10.1089/hum.2011.069] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Leber congenital amaurosis (LCA) is a severe retinal dystrophy manifesting from early infancy as poor vision or blindness. Loss-of-function mutations in GUCY2D cause LCA1 and are one of the most common causes of LCA, accounting for 20% of all cases. Human GUCY2D and mouse Gucy2e genes encode guanylate cyclase-1 (GC1), which is responsible for restoring the dark state in photoreceptors after light exposure. The Gucy2e(-/-) mouse shows partially diminished rod function, but an absence of cone function before degeneration. Although the cones appear morphologically normal, they exhibit mislocalization of proteins involved in phototransduction. In this study we tested the efficacy of an rAAV2/8 vector containing the human rhodopsin kinase promoter and the human GUCY2D gene. Following subretinal delivery of the vector in Gucy2e(-/-) mice, GC1 protein was detected in the rod and cone outer segments, and in transduced areas of retina cone transducin was appropriately localized to cone outer segments. Moreover, we observed a dose-dependent restoration of rod and cone function and an improvement in visual behavior of the treated mice. Most importantly, cone preservation was observed in transduced areas up to 6 months post injection. To date, this is the most effective rescue of the Gucy2e(-/-) mouse model of LCA and we propose that a vector, similar to the one used in this study, could be suitable for use in a clinical trial of gene therapy for LCA1.
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Affiliation(s)
- Marija Mihelec
- Department of Genetics, University College London, Institute of Ophthalmology, London, United Kingdom
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Georgiadis A, Tschernutter M, Bainbridge JWB, Balaggan KS, Mowat F, West EL, Munro PMG, Thrasher AJ, Matter K, Balda MS, Ali RR. The tight junction associated signalling proteins ZO-1 and ZONAB regulate retinal pigment epithelium homeostasis in mice. PLoS One 2010; 5:e15730. [PMID: 21209887 PMCID: PMC3012699 DOI: 10.1371/journal.pone.0015730] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Accepted: 11/22/2010] [Indexed: 12/14/2022] Open
Abstract
Cell-cell adhesion regulates the development and function of epithelia by providing mechanical support and by guiding cell proliferation and differentiation. The tight junction (TJ) protein zonula occludens (ZO)-1 regulates cell proliferation and gene expression by inhibiting the activity of the Y-box transcription factor ZONAB in cultured epithelial cells. We investigated the role of this TJ-associated signalling pathway in the retinal pigment epithelium (RPE) in vivo by lentivirally-mediated overexpression of ZONAB, and knockdown of its cellular inhibitor ZO-1. Both overexpression of ZONAB or knockdown of ZO-1 resulted in increased RPE proliferation, and induced ultrastructural changes of an epithelial-mesenchymal transition (EMT)-like phenotype. Electron microscopy analysis revealed that transduced RPE monolayers were disorganised with increased pyknosis and monolayer breaks, correlating with increased expression of several EMT markers. Moreover, fluorescein angiography analysis demonstrated that the increased proliferation and EMT-like phenotype induced by overexpression of ZONAB or downregulation of ZO-1 resulted in RPE dysfunction. These findings demonstrate that ZO-1 and ZONAB are critical for differentiation and homeostasis of the RPE monolayer and may be involved in RPE disorders such as proliferative vitroretinopathy and atrophic age-related macular degeneration.
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Affiliation(s)
- Anastasios Georgiadis
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, United Kingdom
- Molecular Immunology Unit, UCL Institute of Child Health, University College London, London, United Kingdom
| | - Marion Tschernutter
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - James W. B. Bainbridge
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Kamaljit S. Balaggan
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Freya Mowat
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Emma L. West
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Peter M. G. Munro
- Electron Microscopy Unit, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Adrian J. Thrasher
- Molecular Immunology Unit, UCL Institute of Child Health, University College London, London, United Kingdom
| | - Karl Matter
- Department of Cell Biology, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Maria S. Balda
- Department of Cell Biology, UCL Institute of Ophthalmology, University College London, London, United Kingdom
| | - Robin R. Ali
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, United Kingdom
- Molecular Immunology Unit, UCL Institute of Child Health, University College London, London, United Kingdom
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Mowat FM, Luhmann UFO, Smith AJ, Lange C, Duran Y, Harten S, Shukla D, Maxwell PH, Ali RR, Bainbridge JWB. HIF-1alpha and HIF-2alpha are differentially activated in distinct cell populations in retinal ischaemia. PLoS One 2010; 5:e11103. [PMID: 20559438 PMCID: PMC2885428 DOI: 10.1371/journal.pone.0011103] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Accepted: 05/17/2010] [Indexed: 11/30/2022] Open
Abstract
Background Hypoxia plays a key role in ischaemic and neovascular disorders of the retina. Cellular responses to oxygen are mediated by hypoxia-inducible transcription factors (HIFs) that are stabilised in hypoxia and induce the expression of a diverse range of genes. The purpose of this study was to define the cellular specificities of HIF-1alpha and HIF-2alpha in retinal ischaemia, and to determine their correlation with the pattern of retinal hypoxia and the expression profiles of induced molecular mediators. Methodology/Principal Findings We investigated the tissue distribution of retinal hypoxia during oxygen-induced retinopathy (OIR) in mice using the bio-reductive drug pimonidazole. We measured the levels of HIF-1alpha and HIF-2alpha proteins by Western blotting and determined their cellular distribution by immunohistochemistry during the development of OIR. We measured the temporal expression profiles of two downstream mediators, vascular endothelial growth factor (VEGF) and erythropoietin (Epo) by ELISA. Pimonidazole labelling was evident specifically in the inner retina. Labelling peaked at 2 hours after the onset of hypoxia and gradually declined thereafter. Marked binding to Müller glia was evident during the early hypoxic stages of OIR. Both HIF-1alpha and HIF-2alpha protein levels were significantly increased during retinal hypoxia but were evident in distinct cellular distributions; HIF-1alpha stabilisation was evident in neuronal cells throughout the inner retinal layers whereas HIF-2alpha was restricted to Müller glia and astrocytes. Hypoxia and HIF-alpha stabilisation in the retina were closely followed by upregulated expression of the downstream mediators VEGF and EPO. Conclusions/Significance Both HIF-1alpha and HIF-2alpha are activated in close correlation with retinal hypoxia but have contrasting cell specificities, consistent with differential roles in retinal ischaemia. Our findings suggest that HIF-2alpha activation plays a key role in regulating the response of Müller glia to hypoxia.
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Affiliation(s)
- Freya M. Mowat
- Department of Genetics, University College London Institute of Ophthalmology, London, United Kingdom
| | - Ulrich F. O. Luhmann
- Department of Genetics, University College London Institute of Ophthalmology, London, United Kingdom
| | - Alexander J. Smith
- Department of Genetics, University College London Institute of Ophthalmology, London, United Kingdom
| | - Clemens Lange
- Department of Genetics, University College London Institute of Ophthalmology, London, United Kingdom
| | - Yanai Duran
- Department of Genetics, University College London Institute of Ophthalmology, London, United Kingdom
| | - Sarah Harten
- Division of Medicine, University College London, London, United Kingdom
| | - Deepa Shukla
- Division of Medicine, University College London, London, United Kingdom
| | | | - Robin R. Ali
- Department of Genetics, University College London Institute of Ophthalmology, London, United Kingdom
| | - James W. B. Bainbridge
- Department of Genetics, University College London Institute of Ophthalmology, London, United Kingdom
- * E-mail:
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Anderson OA, Bainbridge JWB, Shima DT. Delivery of anti-angiogenic molecular therapies for retinal disease. Drug Discov Today 2010; 15:272-82. [PMID: 20184967 DOI: 10.1016/j.drudis.2010.02.004] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Revised: 02/10/2010] [Accepted: 02/15/2010] [Indexed: 02/07/2023]
Abstract
Angiogenic diseases of the retina are the leading cause of blindness in the developed world. The development of anti-angiogenic molecular therapies has transformed the prognosis of these conditions, especially age-related macular degeneration. With these new treatments comes the new challenge of delivering an effective dosage to the retina, over a prolonged period of time and in a safe and cost-effective manner. A range of new anti-angiogenics are on the horizon, offering new and varied modes of drug delivery. In addition, a range of new sustained-release drug delivery technologies are being developed.
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Affiliation(s)
- Owen A Anderson
- UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V9EL, United Kingdom.
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Georgiadis A, Tschernutter M, Bainbridge JWB, Robbie SJ, McIntosh J, Nathwani AC, Smith AJ, Ali RR. AAV-mediated knockdown of peripherin-2 in vivo using miRNA-based hairpins. Gene Ther 2009; 17:486-93. [PMID: 20010626 DOI: 10.1038/gt.2009.162] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Gene therapy for inherited retinal degeneration in which expression of a mutant allele has a gain-of-function effect on photoreceptor cells is likely to depend on efficient silencing of the mutated allele. Peripherin-2 (Prph2, also known as peripherin/RDS) is an abundantly expressed photoreceptor-specific gene. In humans, gain-of-function mutations in PRPH2 result in both autosomal dominant retinitis pigmentosa and dominant maculopathies. Gene-silencing strategies for these conditions include RNA interference by short hairpin RNAs (shRNAs). Recent evidence suggests that microRNA (miRNA)-based hairpins may offer a safer and more effective alternative. In this study, we used for the first time a virally transferred miRNA-based hairpin to silence Prph2 in the murine retina. The results show that an miRNA-based shRNA can efficiently and specifically silence Prph2 in vivo as early as 3 weeks after AAV2/8-mediated subretinal delivery, leading to a nearly 50% reduction of photoreceptor cells after 5 weeks. We conclude that miRNA-based hairpins can achieve rapid and robust gene silencing after efficient vector-mediated delivery to the retina. The rationale of using an miRNA-based template to improve the silencing efficiency of a hairpin may prove valuable for allele-specific silencing in which the choice for an RNAi target is limited and offers an alternative therapeutic strategy for the treatment of dominant retinopathies.
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Affiliation(s)
- A Georgiadis
- Department of Molecular Therapy, Institute of Ophthalmology, University College London, London, UK
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41
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Barker SE, Broderick CA, Robbie SJ, Duran Y, Natkunarajah M, Buch P, Balaggan KS, MacLaren RE, Bainbridge JWB, Smith AJ, Ali RR. Subretinal delivery of adeno-associated virus serotype 2 results in minimal immune responses that allow repeat vector administration in immunocompetent mice. J Gene Med 2009; 11:486-97. [PMID: 19340848 PMCID: PMC2841821 DOI: 10.1002/jgm.1327] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Background Adeno-associated virus serotype 2 (AAV2) vectors show considerable promise for ocular gene transfer. However, one potential barrier to efficacious long-term therapy is the development of immune responses against the vector or transgene product. Methods We evaluated cellular and humoural responses in mice following both single and repeated subretinal administration of AAV2, and examined their effects on RPE65 and green fluorescent protein transgene expression. Results Following subretinal administration of vector, splenocytes and T-cells from draining lymph nodes showed minimal activation following stimulation by co-culture with AAV2. Neutralizing antibodies (NAbs) were not detected in the ocular fluids of any mice receiving AAV2 or in the serum of mice receiving a lower dose. NAbs were present in the serum of a proportion of mice receiving a higher dose of the vector. Furthermore, no differences in immunoglobulin titre in serum or ocular fluids against RPE65 protein or AAV2 capsid between treated and control mice were detected. Histological examination showed no evidence of retinal toxicity or leukocyte infiltration compared to uninjected eyes. Repeat administration of low-dose AAV.hRPE65.hRPE65 to both eyes of RPE65−/− mice resulted in transgene expression and functional rescue, but re-administration of high-dose AAV2 resulted in boosted NAb titres and variable transgene expression in the second injected eye. Conclusions These data, which were obtained in mice, suggest that, following subretinal injection, immune responses to AAV2 are dose-dependent. Low-dose AAV2 is well tolerated in the eye, with minimal immune responses, and transgene expression after repeat administration of vector is achievable. Higher doses lead to the expression of NAbs that reduce the efficacy of repeated vector administration. Copyright © 2009 John Wiley & Sons, Ltd.
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Affiliation(s)
- Susie E Barker
- Division of Molecular Therapy, UCL Institute of Ophthalmology, London, UK.
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42
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Luhmann UFO, Robbie S, Munro PMG, Barker SE, Duran Y, Luong V, Fitzke FW, Bainbridge JWB, Ali RR, MacLaren RE. The drusenlike phenotype in aging Ccl2-knockout mice is caused by an accelerated accumulation of swollen autofluorescent subretinal macrophages. Invest Ophthalmol Vis Sci 2009; 50:5934-43. [PMID: 19578022 DOI: 10.1167/iovs.09-3462] [Citation(s) in RCA: 166] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Drusen, which are defined clinically as yellowish white spots in the outer retina, are cardinal features of age-related macular degeneration (AMD). Ccl2-knockout (Ccl2(-/-)) mice have been reported to develop drusen and phenotypic features similar to AMD, including an increased susceptibility to choroidal neovascularization (CNV). This study was conducted to investigate the nature of the drusenlike lesions in vivo and further evaluate the Ccl2(-/-) mouse as a model of AMD. METHODS The eyes of 2- to 25-month-old Ccl2(-/-) and C57Bl/6 mice were examined in vivo by autofluorescence scanning laser ophthalmoscopy (AF-SLO) and electroretinography, and the extent of laser-induced CNV was measured by fluorescein fundus angiography. The retinal morphology was also assessed by immunohistochemistry and quantitative histologic and ultrastructural morphometry. RESULTS The drusenlike lesions of Ccl2(-/-) mice comprised accelerated accumulation of swollen CD68(+), F4/80(+) macrophages in the subretinal space that were apparent as autofluorescent foci on AF-SLO. These macrophages contained pigment granules and phagosomes with outer segment and lipofuscin inclusions that may account for their autofluorescence. Only age-related retinal pigment epithelium (RPE) damage, photoreceptor loss, and sub-RPE deposits were observed but, despite the accelerated accumulation of macrophages, we identified no spontaneous development of CNV in the senescent mice and found a reduced susceptibility to laser-induced CNV in the Ccl2(-/-) mice. CONCLUSIONS These findings suggest that the lack of Ccl2 leads to a monocyte/macrophage-trafficking defect during aging and to an impaired recruitment of these cells to sites of laser injury. Other, previously described features of Ccl2(-/-) mice that are similar to AMD may be the result of aging alone.
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Affiliation(s)
- Ulrich F O Luhmann
- Department of Genetics, UCL Institute of Ophthalmology, London, United Kingdom.
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44
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Trittibach P, Barker SE, Broderick CA, Natkunarajah M, Duran Y, Robbie SJ, Bainbridge JWB, Smith AJ, Sarra GM, Dick AD, Ali RR. Lentiviral-vector-mediated expression of murine IL-1 receptor antagonist or IL-10 reduces the severity of endotoxin-induced uveitis. Gene Ther 2008; 15:1478-88. [PMID: 18580969 DOI: 10.1038/gt.2008.109] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Uveitis is a sight threatening inflammatory disorder that remains a significant cause of visual loss. We investigated lentiviral gene delivery of interleukin 1 receptor antagonist (IL-1ra) or interleukin (IL)-10 to ameliorate murine endotoxin-induced uveitis (EIU). An human immunodeficiency virus-1-based vector containing the mIL-1ra or mIL-10 cDNA demonstrated high expression of biologically active cytokine. Following administration of Lenti.GFP into the anterior chamber, transgene expression was observed in corneal endothelial cells, trabecular meshwork and iris cells. To treat EIU, mice were injected with Lenti.IL-1ra, Lenti.IL-10 or a combination of these. EIU was induced 14 days after vector administration and mice were culled 12 h following disease induction. Lenti.IL-1ra or Lenti.IL-10-treated eyes showed significantly lower mean inflammatory cell counts in the anterior and posterior chambers compared with controls. The aqueous total protein content was also significantly lower in treated eyes, demonstrating better preservation of the blood-ocular barrier. Furthermore, the treated eyes showed less in vivo fluorescein leakage from inner retinal vessels compared with controls. The combination of both IL-1ra and IL-10 had no additive effect. Thus, lentiviral gene delivery of IL-1ra or IL-10 significantly reduces the severity of experimental uveitis, suggesting that lentiviral-mediated expression of immunomodulatory genes in the anterior chamber offers an opportunity to treat uveitis.
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Affiliation(s)
- P Trittibach
- Division of Molecular Therapy, Institute of Ophthalmology, University College London, London, UK
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45
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Bainbridge JWB, Smith AJ, Barker SS, Robbie S, Henderson R, Balaggan K, Viswanathan A, Holder GE, Stockman A, Tyler N, Petersen-Jones S, Bhattacharya SS, Thrasher AJ, Fitzke FW, Carter BJ, Rubin GS, Moore AT, Ali RR. Effect of gene therapy on visual function in Leber's congenital amaurosis. N Engl J Med 2008; 358:2231-9. [PMID: 18441371 DOI: 10.1056/nejmoa0802268] [Citation(s) in RCA: 1399] [Impact Index Per Article: 87.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Early-onset, severe retinal dystrophy caused by mutations in the gene encoding retinal pigment epithelium-specific 65-kD protein (RPE65) is associated with poor vision at birth and complete loss of vision in early adulthood. We administered to three young adult patients subretinal injections of recombinant adeno-associated virus vector 2/2 expressing RPE65 complementary DNA (cDNA) under the control of a human RPE65 promoter. There were no serious adverse events. There was no clinically significant change in visual acuity or in peripheral visual fields on Goldmann perimetry in any of the three patients. We detected no change in retinal responses on electroretinography. One patient had significant improvement in visual function on microperimetry and on dark-adapted perimetry. This patient also showed improvement in a subjective test of visual mobility. These findings provide support for further clinical studies of this experimental approach in other patients with mutant RPE65. (ClinicalTrials.gov number, NCT00643747 [ClinicalTrials.gov].).
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Abstract
The eye has unique advantages as a target organ for gene therapy of both inherited and acquired ocular disorders and offers a valuable model system for gene therapy. The eye is readily accessible to phenotypic examination and investigation of therapeutic effects in vivo by fundus imaging and electrophysiological techniques. Considerable progress has been made in the development of gene replacement therapies for retinal degenerations resulting from gene defects in photoreceptor cells (rds, RPGRIP, RS-1) and in retinal pigment epithelial cells (MerTK, RPE65, OA1) using recombinant adeno-associated virus and lentivirus-based vectors. Gene therapy also offers a potentially powerful approach to the treatment of complex acquired disorders such as those involving angiogenesis, inflammation and degeneration, by the targeted sustained intraocular delivery of therapeutic proteins. Proposals for clinical trials of gene therapy for early-onset retinal degeneration owing to defects in the gene encoding the visual cycle protein RPE65 have recently received ethical approval.
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Affiliation(s)
- J W B Bainbridge
- Division of Molecular Therapy, Institute of Ophthalmology, University College London, London, UK
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47
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Balaggan KS, Binley K, Esapa M, MacLaren RE, Iqball S, Duran Y, Pearson RA, Kan O, Barker SE, Smith AJ, Bainbridge JWB, Naylor S, Ali RR. EIAV vector-mediated delivery of endostatin or angiostatin inhibits angiogenesis and vascular hyperpermeability in experimental CNV. Gene Ther 2006; 13:1153-65. [PMID: 16572190 DOI: 10.1038/sj.gt.3302769] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
We evaluated the efficacy of equine infectious anaemia virus (EIAV)-based lentiviral vectors encoding endostatin (EIAV.endostatin) or angiostatin (EIAV.angiostatin) in inhibiting angiogenesis and vascular hyperpermeability in the laser-induced model of choroidal neovascularisation (CNV). Equine infectious anaemia virus.endostatin, EIAV.angiostatin or control (EIAV.null) vectors were administered into the subretinal space of C57Bl/6J mice. Two weeks after laser injury CNV areas and the degree of vascular hyperpermeability were measured by image analysis of in vivo fluorescein angiograms. Compared with EIAV.null-injected eyes, EIAV.endostatin resulted in a 59.5% (P<0.001) reduction in CNV area and a reduction in hyperpermeability of 25.6% (P<0.05). Equine infectious anaemia virus.angiostatin resulted in a 50.0% (P<0.05) reduction in CNV area and a 23.9% (P<0.05) reduction in hyperpermeability. Equine infectious anaemia virus.endostatin, but not EIAV.angiostatin significantly augmented the frequency of apoptosis within the induced CNV as compared with injected controls. TdT-dUTP terminal nick end labeling analysis 5 weeks post-injection, and histological and retinal flatmount analysis 12 months post-injection revealed no evidence of vector- or transgene expression-related deleterious effects on neurosensory retinal cells, or mature retinal vasculature in non-lasered eyes. Highly expressing EIAV-based vectors encoding endostatin or angiostatin effectively control angiogenesis and hyperpermeability in experimental CNV without long-term deleterious effects, supporting the use of such a strategy in the management of patients with exudative age-related macular degeneration.
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Affiliation(s)
- K S Balaggan
- Division of Molecular Therapy, Institute of Ophthalmology, London, UK.
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Balaggan KS, Binley K, Esapa M, Iqball S, Askham Z, Kan O, Tschernutter M, Bainbridge JWB, Naylor S, Ali RR. Stable and efficient intraocular gene transfer using pseudotyped EIAV lentiviral vectors. J Gene Med 2006; 8:275-85. [PMID: 16299834 DOI: 10.1002/jgm.845] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND We have developed minimal non-primate lentiviral vectors based on the equine infectious anaemia virus (EIAV). We evaluated the in vivo expression profiles of these vectors delivered regionally to ocular tissues to define their potential utility in ocular gene therapy. METHODS EIAV vectors pseudotyped with VSV-G or rabies-G envelope proteins were delivered subretinally, intravitreally or into the anterior chambers (intracameral administration) in mice. Reporter gene (eGFP) expression was analysed using in vivo retinal imaging or histological examination of eyes and brains at intervals between 3 days and 16 months. We investigated the effects of vector titre, pseudotype, genome configuration, site of intraocular administration, intentional retinal trauma and the degree of retinal maturation on the spatial and temporal expression profiles of these vectors. RESULTS Subretinal vector delivery resulted in efficient and stable transduction of retinal pigment epithelial (RPE) cells and variable transduction of photoreceptors up to 16 months post-injection. Retinal trauma facilitated the local transduction of neurosensory retinal cells. Intracameral administration of VSV-G- but not rabies-G-pseudotyped vectors produced stable eGFP expression in corneal endothelial cells and trabecular meshwork. CONCLUSIONS The cellular tropism and expression kinetics of optimised EIAV vectors after intraocular administration make them attractive vehicles for delivering therapeutic genes in the management of inherited and acquired retinal and anterior segment disorders.
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Affiliation(s)
- K S Balaggan
- Division of Molecular Therapy, Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
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49
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Tschernutter M, Schlichtenbrede FC, Howe S, Balaggan KS, Munro PM, Bainbridge JWB, Thrasher AJ, Smith AJ, Ali RR. Long-term preservation of retinal function in the RCS rat model of retinitis pigmentosa following lentivirus-mediated gene therapy. Gene Ther 2005; 12:694-701. [PMID: 15660111 DOI: 10.1038/sj.gt.3302460] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The Royal College of Surgeons (RCS) rat is a well-characterized model of autosomal recessive retinitis pigmentosa (RP) due to a defect in the retinal pigment epithelium (RPE). It is homozygous for a null mutation in the gene encoding , a receptor tyrosine kinase found in RPE cells, that is required for phagocytosis of shed photoreceptor outer segments. The absence of Mertk results in accumulation of outer segment debris. This subsequently leads to progressive loss of photoreceptor cells. In order to evaluate the efficacy of lentiviral-mediated gene replacement therapy in the RCS rat, we produced recombinant VSV-G pseudotyped HIV-1-based lentiviruses containing a murine Mertk cDNA driven by a spleen focus forming virus (SFFV) promoter. The vector was subretinally injected into the right eye of 10-day-old RCS rats; the left eye was left untreated as an internal control. Here, we present a detailed assessment of the duration and extent of the morphological rescue and the resulting functional benefits. We examined animals at various time points over a period of 7 months by light and electron microscopy, and electroretinography. We observed correction of the phagocytic defect, slowing of photoreceptor cell loss and preservation of retinal function for up to 7 months. This study demonstrates the potential of gene therapy approaches for the treatment of retinal degenerations caused by defects specific to the RPE and supports the use of lentiviral vectors for the treatment of such disorders.
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Affiliation(s)
- M Tschernutter
- Division of Molecular Therapy, Institute of Ophthalmology, University College London, UK
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50
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Schlichtenbrede FC, Smith AJ, Bainbridge JWB, Thrasher AJ, Salt TE, Ali RR. Improvement of neuronal visual responses in the superior colliculus in Prph2(Rd2/Rd2) mice following gene therapy. Mol Cell Neurosci 2004; 25:103-10. [PMID: 14962744 DOI: 10.1016/j.mcn.2003.09.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2003] [Revised: 09/03/2003] [Accepted: 09/29/2003] [Indexed: 10/26/2022] Open
Abstract
Inherited retinal degenerations are a major cause of blindness for which there are currently no effective therapies. Significant progress concerning in vivo gene transfer has allowed retardation of degeneration or retinal functional improvement in different animal models. To date, there has been no evaluation of the impact of these treatments on higher visual function, a critical step for validating gene therapy treatment strategies. Here, we have used adeno-associated (AAV2)-mediated gene transfer of Prph2 in the Prph2(Rd2/Rd2) mouse model. We then assessed higher visual function by recording from central visually responsive neurons in the superior colliculus and improvements were correlated in individual animals with retinal function (ERG) and histological and biochemical changes. Although gene replacement therapy only partially restores photoreceptor morphology, it results in a 300% increase of the visual cycle protein rhodopsin, leading to retinal function improvement (250% increase of b-wave amplitude) and significantly higher central visual responses (166% increase at 24 cd/m(2)). These findings suggest that gene replacement therapy leading to even relatively modest structural improvement may result in improved central visual function.
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Affiliation(s)
- F C Schlichtenbrede
- Department of Molecular Genetics, Institute of Ophthalmology, University College London, London EC1V 9EL, UK
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