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Liu S, Matsuo T, Hosoya O, Uchida T. Photoelectric Dye Used for Okayama University-Type Retinal Prosthesis Reduces the Apoptosis of Photoreceptor Cells. J Ocul Pharmacol Ther 2017; 33:149-160. [PMID: 28085534 PMCID: PMC5385417 DOI: 10.1089/jop.2016.0093] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Purpose: Our previous study demonstrated that photoelectric dye-coupled polyethylene film (Okayama University-type retinal prosthesis), which was implanted in subretinal space of the eyes of Royal College of Surgeons (RCS) rats, prevented retinal neurons from apoptotic death. In this study, we aimed to examine whether photoelectric dye itself would protect retinal neurons from apoptosis in RCS rats. Methods: RCS rats received intravitreous injection of different concentrations of the dye in the left eye and housed under a 12-h light–dark cycle. Saline injection in the right eye served as control. In addition, RCS rats with dye injection were kept in 24-h daily dark condition. Sections were processed for terminal deoxynucleotidyl transferase-mediated fluorescein-conjugated-dUTP nick-end-labeling (TUNEL) assay and immunohistochemical staining of glial fibrillary acidic protein (GFAP) and protein kinase Cα (PKCα). Results: The number of TUNEL-positive cells significantly decreased in the retina of dye-injected eyes compared with those in saline-injected eyes (P = 0.0001, 2-factor analysis of variance [ANOVA]), under 12-h light–dark cycle. Significant decrease of TUNEL-positive cells was noted in the retina of rats with dye injection compared with those with saline injection, kept under 24-h dark condition (P = 0.0001, 2-factor ANOVA). Immunoreactive area for GFAP decreased significantly in the retina of dye-injected eyes compared with that in controls (P = 0.0001, 2-factor ANOVA), whereas immunoreactive area for PKCα increased significantly in the retina of dye-injected eyes compared with that in controls (P = 0.01, 2-factor ANOVA). Conclusions: Photoelectric dye inhibits apoptotic death of photoreceptor cells in RCS rats and downregulates GFAP expression in retinal Müller cells. Photoelectric dye may be a candidate agent for neuroprotection in retinitis pigmentosa and other retinal diseases.
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Affiliation(s)
- Shihui Liu
- 1 Department of Ophthalmology, Okayama University Medical School and Graduate School of Medicine , Dentistry, and Pharmaceutical Sciences, Okayama City, Japan
| | - Toshihiko Matsuo
- 1 Department of Ophthalmology, Okayama University Medical School and Graduate School of Medicine , Dentistry, and Pharmaceutical Sciences, Okayama City, Japan
| | - Osamu Hosoya
- 2 Department of Medical Neurobiology, Okayama University Medical School and Graduate School of Medicine , Dentistry, and Pharmaceutical Sciences, Okayama City, Japan
| | - Tetsuya Uchida
- 3 Polymer Materials Science, Okayama University Faculty of Engineering and Graduate School of Natural Science and Technology , Okayama City, Japan
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2
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Shen W, Chung SH, Irhimeh MR, Li S, Lee SR, Gillies MC. Systemic administration of erythropoietin inhibits retinopathy in RCS rats. PLoS One 2014; 9:e104759. [PMID: 25119659 PMCID: PMC4132022 DOI: 10.1371/journal.pone.0104759] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 07/12/2014] [Indexed: 12/17/2022] Open
Abstract
Objective Royal College of Surgeons (RCS) rats develop vasculopathy as photoreceptors degenerate. The aim of this study was to examine the effect of erythropoietin (EPO) on retinopathy in RCS rats. Methods Fluorescein angiography was used to monitor retinal vascular changes over time. Changes in retinal glia and vasculature were studied by immunostaining. To study the effects of EPO on retinal pathology, EPO (5000 IU/kg) was injected intraperitoneally in 14 week old normal and RCS rats twice a week for 4 weeks. Changes in the retinal vasculature, glia and microglia, photoreceptor apoptosis, differential expression of p75 neurotrophin receptor (p75NTR), pro-neurotrophin 3 (pro-NT3), tumour necrosis factor-α (TNFα), pigment epithelium derived factor (PEDF) and vascular endothelial growth factor-A (VEGF-A), the production of CD34+ cells and mobilization of CD34+/VEGF-R2+ cells as well as recruitment of CD34+ cells into the retina were examined after EPO treatment. Results RCS rats developed progressive capillary dropout and subretinal neovascularization which were accompanied by retinal gliosis. Systemic administration of EPO stabilized the retinal vasculature and inhibited the development of focal vascular lesions. Further studies showed that EPO modulated retinal gliosis, attenuated photoreceptor apoptosis and p75NTR and pro-NT3 upregulation, promoted the infiltration of ramified microglia and stimulated VEGF-A expression but had little effect on TNFα and PEDF expression. EPO stimulated the production of red and white blood cells and CD34+ cells along with effective mobilization of CD34+/VEGF-R2+ cells. Immunofluorescence study demonstrated that EPO enhanced the recruitment of CD34+ cells into the retina. Conclusions Our results suggest that EPO has therapeutic potentials in treatment of neuronal and vascular pathology in retinal disease. The protective effects of EPO on photoreceptors and the retinal vasculature may involve multiple mechanisms including regulation of retinal glia and microglia, inhibition of p75NTR-pro-NT3 signaling together with stimulation of production and mobilization of bone marrow derived cells.
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Affiliation(s)
- Weiyong Shen
- Save Sight Institute, the University of Sydney, Sydney, Australia
| | - Sook H Chung
- Save Sight Institute, the University of Sydney, Sydney, Australia
| | | | - Shiying Li
- Save Sight Institute, the University of Sydney, Sydney, Australia; Southwest Hospital/Southwest Eye Hospital, Third Military Medical University, Chongqing, China
| | - So-Ra Lee
- Save Sight Institute, the University of Sydney, Sydney, Australia
| | - Mark C Gillies
- Save Sight Institute, the University of Sydney, Sydney, Australia
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3
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Li F, Li Y, Li M, Sun Y, Bai Y, Yang F, Guo J, Chen Y, Huang L, Li X. ABCA1 rs1883025 Polymorphism Shows No Association with Neovascular Age-Related Macular Degeneration or Polypoidal Choroidal Vasculopathy in a Northern Chinese Population. Ophthalmic Res 2014; 51:210-5. [DOI: 10.1159/000357978] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 12/10/2013] [Indexed: 11/19/2022]
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4
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Barbash IM, Cecchini S, Faranesh AZ, Virag T, Li L, Yang Y, Hoyt RF, Kornegay JN, Bogan JR, Garcia L, Lederman RJ, Kotin RM. MRI roadmap-guided transendocardial delivery of exon-skipping recombinant adeno-associated virus restores dystrophin expression in a canine model of Duchenne muscular dystrophy. Gene Ther 2013; 20:274-82. [PMID: 22551778 PMCID: PMC3424392 DOI: 10.1038/gt.2012.38] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 03/29/2012] [Indexed: 01/16/2023]
Abstract
Duchenne muscular dystrophy (DMD) cardiomyopathy patients currently have no therapeutic options. We evaluated catheter-based transendocardial delivery of a recombinant adeno-associated virus (rAAV) expressing a small nuclear U7 RNA (U7smOPT) complementary to specific cis-acting splicing signals. Eliminating specific exons restores the open reading frame resulting in translation of truncated dystrophin protein. To test this approach in a clinically relevant DMD model, golden retriever muscular dystrophy (GRMD) dogs received serotype 6 rAAV-U7smOPT via the intracoronary or transendocardial route. Transendocardial injections were administered with an injection-tipped catheter and fluoroscopic guidance using X-ray fused with magnetic resonance imaging (XFM) roadmaps. Three months after treatment, tissues were analyzed for DNA, RNA, dystrophin protein, and histology. Whereas intracoronary delivery did not result in effective transduction, transendocardial injections, XFM guidance, enabled 30±10 non-overlapping injections per animal. Vector DNA was detectable in all samples tested and ranged from <1 to >3000 vector genome copies per cell. RNA analysis, western blot analysis, and immunohistology demonstrated extensive expression of skipped RNA and dystrophin protein in the treated myocardium. Left ventricular function remained unchanged over a 3-month follow-up. These results demonstrated that effective transendocardial delivery of rAAV-U7smOPT was achieved using XFM. This approach restores an open reading frame for dystrophin in affected dogs and has potential clinical utility.
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Affiliation(s)
- I M Barbash
- Cardiovascular and Pulmonary Branch, Division of Intramural Research, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD, USA
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5
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Cheng Y, Huang L, Li X, Zhou P, Zeng W, Zhang C. Genetic and functional dissection of ARMS2 in age-related macular degeneration and polypoidal choroidal vasculopathy. PLoS One 2013; 8:e53665. [PMID: 23326481 PMCID: PMC3541181 DOI: 10.1371/journal.pone.0053665] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2012] [Accepted: 12/03/2012] [Indexed: 12/18/2022] Open
Abstract
Age-related maculopathy susceptibility 2(ARMS2) was suggested to be associated with neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV) in multiple genetic studies in Caucasians and Japanese. To date, no biological properties have been attributed to the putative protein in nAMD and PCV. The complete genes of ARMS2 and HTRA1 including all exons and the promoter region were assessed using direct sequencing technology in 284 unrelated mainland northern Chinese individuals: 96 nAMD patients, 92 PCV patients and 96 controls. Significant associations with both nAMD and PCV were observed in 2 polymorphisms of ARMS2 and HTRA1 rs11200638, with different genotypic distributions between nAMD and PCV (p<0.001). After adjusting for rs11200638, ARMS2 rs10490924 remained significantly associated with nAMD and PCV (p<0.001). Then we overexpressed wild-type ARMS2 and ARMS2 A69S mutation (rs10490924) in RF/6A cells and RPE cells as in vitro study model. Cell proliferation, attachment, migration and tube formation were analyzed for the first time. Compare with wild-type ARMS2, A69S mutation resulted in a significant increase in proliferation and attachment but inhibited cell migration. Moreover, neither wild-type ARMS2 nor A69S mutation affected tube formation of RF/6A cells. There is a strong and consistent association of the ARMS2/HTRA1 locus with both nAMD and PCV, suggesting the two disorders share, at least partially, similar molecular mechanisms. Neither wild-type ARMS2 nor A69S mutation had direct association with neovascularisation in the pathogenesis of AMD.
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Affiliation(s)
- Yong Cheng
- Department of Ophthalmology, People’s Hospital, Peking University, Beijing, China
- Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, China
| | - LvZhen Huang
- Department of Ophthalmology, People’s Hospital, Peking University, Beijing, China
- Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, China
| | - Xiaoxin Li
- Department of Ophthalmology, People’s Hospital, Peking University, Beijing, China
- Key Laboratory of Vision Loss and Restoration, Ministry of Education, Beijing, China
| | - Peng Zhou
- Department of Ophthalmology, Eye and ENT Hospital of Fudan University, Shanghai, China
| | - Wotan Zeng
- Chinese National Human Genome Center, Beijing, China
| | - ChunFang Zhang
- Department of Clinical Epidemiology, People’s Hospital, Peking University, Beijing, China
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6
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Han Z, Conley SM, Makkia R, Guo J, Cooper MJ, Naash MI. Comparative analysis of DNA nanoparticles and AAVs for ocular gene delivery. PLoS One 2012; 7:e52189. [PMID: 23272225 PMCID: PMC3525534 DOI: 10.1371/journal.pone.0052189] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 11/13/2012] [Indexed: 12/19/2022] Open
Abstract
Gene therapy is a critical tool for the treatment of monogenic retinal diseases. However, the limited vector capacity of the current benchmark delivery strategy, adeno-associated virus (AAV), makes development of larger capacity alternatives, such as compacted DNA nanoparticles (NPs), critical. Here we conduct a side-by-side comparison of self-complementary AAV and CK30PEG NPs using matched ITR plasmids. We report that although AAVs are more efficient per vector genome (vg) than NPs, NPs can drive gene expression on a comparable scale and longevity to AAV. We show that subretinally injected NPs do not leave the eye while some of the AAV-injected animals exhibited vector DNA and GFP expression in the visual pathways of the brain from PI-60 onward. As a result, these NPs have the potential to become a successful alternative for ocular gene therapy, especially for the multitude of genes too large for AAV vectors.
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Affiliation(s)
- Zongchao Han
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Shannon M. Conley
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Rasha Makkia
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Junjing Guo
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
| | - Mark J. Cooper
- Copernicus Therapeutics, Inc., Cleveland, Ohio, United States of America
| | - Muna I. Naash
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, United States of America
- * E-mail:
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7
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Rakoczy EP, Ali Rahman IS, Binz N, Li CR, Vagaja NN, de Pinho M, Lai CM. Characterization of a mouse model of hyperglycemia and retinal neovascularization. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:2659-70. [PMID: 20829433 DOI: 10.2353/ajpath.2010.090883] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
One of the limitations of research into diabetic retinopathy is the lack of suitable animal models. To study how the two important factors--hyperglycemia and vascular endothelial growth factor--interact in diabetic retinopathy, the Akimba mouse (Ins2AkitaVEGF+/-) was generated by crossing the Akita mouse (Ins2Akita) with the Kimba mouse (VEGF+/+). C57Bl/6 and the parental and Akimba mouse lines were characterized by biometric measurements, histology, immunohistochemistry, and Spectralis Heidelberg retinal angiography and optical coherence tomography. The Akimba line not only retained the characteristics of the parental strains, such as developing hyperglycemia and retinal neovascularization, but developed higher blood glucose levels at a younger age and had worse kidney-body weight ratios than the Akita line. With aging, the Akimba line demonstrated enhanced photoreceptor cell loss, thinning of the retina, and more severe retinal vascular pathology, including more severe capillary nonperfusion, vessel constriction, beading, neovascularization, fibroses, and edema, compared with the Kimba line. The vascular changes were associated with major histocompatibility complex class II+ cellular staining throughout the retina. Together, these observations suggest that hyperglycemia resulted in higher prevalences of edema and exacerbated the vascular endothelial growth factor-driven neovascular and retinal changes in the Akimba line. Thus, the Akimba line could become a useful model for studying the interplay between hyperglycemia and vascular endothelial growth factor and for testing treatment strategies for potentially blinding complications, such as edema.
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Affiliation(s)
- Elizabeth P Rakoczy
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Crawley, Australia.
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8
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Shen W, Li S, Chung SH, Gillies MC. Retinal vascular changes after glial disruption in rats. J Neurosci Res 2010; 88:1485-99. [PMID: 20029988 DOI: 10.1002/jnr.22317] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Glial dysfunction is found in a number of retinal vascular diseases but its link with blood-retinal barrier (BRB) breakdown remains poorly understood. The present study tested the hypothesis that glial dysfunction is a major contributor to the BRB breakdown that is a hallmark of retinal vascular diseases. We investigated the specificity of the purportedly selective glial toxin, DL-alpha-aminoadipic acid (DL-alpha-AAA) on different types of ocular cells in vitro and then tested the effect of glial disruption on retinal vasculature after intraocular injection of DL-alpha-AAA or siRNA targeting glutamine synthetase (GS) in rats. DL-alpha-AAA was toxic to astrocytes and Müller cells but not to other types of BRB-related cells in vitro. Subretinal injection of DL-alpha-AAA disrupted retinal glial cells, induced vascular telangiectasis and increased vascular permeability from 4 days to over 2 months post-injection. Vascular changes induced by DL-alpha-AAA were observed predominantly in regions of glial disruption, as reflected by reduced expression of GS and increased expression of glial fibrillary acidic protein and vimentin. Confocal microscopy showed changes in all three layers of the retinal vasculature, which co-localised with areas of Müller cell disruption. Double labeling immunohistochemistry revealed that retinal glial disruption after DL-alpha-AAA injection was accompanied by increased expression of vascular endothelial growth factor and reduced expression of the tight junction protein claudin-5. Intravitreal injection of GS siRNA induced similar changes in Müller cells and BRB breakdown. Our data are consistent with the hypothesis that glial dysfunction is a primary contributor to the BRB breakdown in retinal vascular diseases.
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Affiliation(s)
- Weiyong Shen
- Save Sight Institute, University of Sydney, Sydney, Australia.
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9
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Development of viral vectors with optimal transgene expression for ocular gene therapies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 613:113-9. [PMID: 18188935 DOI: 10.1007/978-0-387-74904-4_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Striving for ideal viral constructs by modifying its structure, including promoters, would make the viral gene therapy more promising. Further assessment of the promoters and their expression profiles such as those shown in Table 1 and new designs of hybrid promoters may achieve optimal expression features for ocular gene therapies.
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10
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Mancuso K, Hendrickson AE, Connor TB, Mauck MC, Kinsella JJ, Hauswirth WW, Neitz J, Neitz M. Recombinant adeno-associated virus targets passenger gene expression to cones in primate retina. JOURNAL OF THE OPTICAL SOCIETY OF AMERICA. A, OPTICS, IMAGE SCIENCE, AND VISION 2007; 24:1411-6. [PMID: 17429487 DOI: 10.1364/josaa.24.001411] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Recombinant adeno-associated virus (rAAV) is a promising vector for gene therapy of photoreceptor-based diseases. Previous studies have demonstrated that rAAV serotypes 2 and 5 can transduce both rod and cone photoreceptors in rodents and dogs, and it can target rods, but not cones in primates. Here we report that using a human cone-specific enhancer and promoter to regulate expression of a green fluorescent protein (GFP) reporter gene in an rAAV-5 vector successfully targeted expression of the reporter gene to primate cones, and the time course of GFP expression was able to be monitored in a living animal using the RetCam II digital imaging system.
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Affiliation(s)
- Katherine Mancuso
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee 53226, USA
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11
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Jacobson SG, Acland GM, Aguirre GD, Aleman TS, Schwartz SB, Cideciyan AV, Zeiss CJ, Komaromy AM, Kaushal S, Roman AJ, Windsor EAM, Sumaroka A, Pearce-Kelling SE, Conlon TJ, Chiodo VA, Boye SL, Flotte TR, Maguire AM, Bennett J, Hauswirth WW. Safety of recombinant adeno-associated virus type 2-RPE65 vector delivered by ocular subretinal injection. Mol Ther 2006; 13:1074-84. [PMID: 16644289 DOI: 10.1016/j.ymthe.2006.03.005] [Citation(s) in RCA: 159] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2005] [Revised: 02/28/2006] [Accepted: 03/01/2006] [Indexed: 01/14/2023] Open
Abstract
AAV2 delivery of the RPE65 gene to the retina of blind RPE65-deficient animals restores vision. This strategy is being considered for human trials in RPE65-associated Leber congenital amaurosis (LCA), but toxicity and dose efficacy have not been defined. We studied ocular delivery of AAV-2/2.RPE65 in RPE65-mutant dogs. There was no systemic toxicity. Ocular examinations showed mild or moderate inflammation that resolved over 3 months. Retinal histopathology indicated that traumatic lesions from the injection were common, but thinning within the injection region occurred only at the two highest vector doses. Biodistribution studies at 3 months postinjection showed no vector in optic nerve or visual centers in the brain and only isolated non-dose-related detection in other organs. We also performed biodistribution studies in normal rats at about 2 weeks and 2 months postinjection and vector was not widespread outside the injected eye. Dose-response results in RPE65-mutant dogs indicated that the highest 1.5-log unit range of vector doses proved efficacious. The efficacy and toxicity limits defined in this study lead to suggestions for the design of a subretinal AAV-2/2.RPE65 human trial of RPE65-associated LCA.
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Affiliation(s)
- Samuel G Jacobson
- Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, PA 19104, USA.
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Constable I, Shen WY, Rakoczy E. Emerging biological therapies for age-related macula degeneration. Expert Opin Biol Ther 2005; 5:1373-85. [PMID: 16197342 DOI: 10.1517/14712598.5.10.1373] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Age-related macular degeneration (AMD) has emerged as the dominant cause of irretrievable visual loss in most developed countries achieving increasing longevity. The major cause of rapid and severe visual loss is the development of choroidal neovascularisation under the macula (exudative or wet AMD). Physical treatments, especially thermal laser and photodynamic therapy following intravenous verteporfin, have made statistically significant but modest progress in limiting visual loss, whereas surgical translocation of the macula and even light or electrically sensitive retinal implants are spectacular, but likely to only ever benefit a few. Intravitreal fine needle injections and slow release implants of steroid derivatives have opened new areas for investigation. The blocking of endothelial receptors for vascular endothelial growth factor by RNA-based aptamer or immune-protected antibody fragments has been the subject of intensive scientific development and large scale clinical trials. This approach may expand the range of AMD patients amenable to treatment. Additional therapeutic gains await measures to modify photoreceptor cell loss and subretinal fibrosis involving the retinal pigment epithelium as well as prevention or treatment for pigment epithelial detachment. Epidemiological associations with smoking and diet, and antioxidant dietary supplements offer important strategies for prevention.
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Affiliation(s)
- Ian Constable
- Lions Eye Institute, Centre for Ophthalmology and Visual Science, University of Western Australia, Nedlands, WA 6009, Australia.
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Lai CM, Shen WY, Brankov M, Lai YKY, Barnett NL, Lee SY, Yeo IYS, Mathur R, Ho JES, Pineda P, Barathi A, Ang CL, Constable IJ, Rakoczy EP. Long-term Evaluation of AAV-Mediated sFlt-1 Gene Therapy for Ocular Neovascularization in Mice and Monkeys. Mol Ther 2005; 12:659-68. [PMID: 16023893 DOI: 10.1016/j.ymthe.2005.04.022] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2005] [Revised: 04/18/2005] [Accepted: 04/28/2005] [Indexed: 10/25/2022] Open
Abstract
Vascular endothelial growth factor (VEGF) is one of the major mediators of retinal ischemia-associated neovascularization. We have shown here that adeno-associated virus (AAV)-mediated expression of sFlt-1, a soluble form of the Flt-1 VEGF receptor, was maintained for up to 8 and 17 months postinjection in mice and in monkeys, respectively. The expression of sFlt-1 was associated with the long-term (8 months) regression of neovascular vessels in 85% of trVEGF029 eyes. In addition, it resulted in the maintenance of retinal morphology, as the majority of the treated trVEGF029 eyes (75%) retained high numbers of photoreceptors, and in retinal function as measured by electroretinography. AAV-mediated expression of sFlt-1 prevented the development of laser photocoagulation-induced choroidal neovascularization in all treated monkey eyes. There were no clinically or histologically detectable signs of toxicity present in either animal model following AAV.sFlt injection. These results suggest that AAV-mediated secretion gene therapy could be considered for treatment of retinal and choroidal neovascularizations.
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Affiliation(s)
- Chooi-May Lai
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Crawley, Australia.
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14
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Lai CM, Yu MJT, Brankov M, Barnett NL, Zhou X, Redmond TM, Narfstrom K, Rakoczy PE. Recombinant adeno-associated virus type 2-mediated gene delivery into the Rpe65-/- knockout mouse eye results in limited rescue. GENETIC VACCINES AND THERAPY 2004; 2:3. [PMID: 15109394 PMCID: PMC416492 DOI: 10.1186/1479-0556-2-3] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/23/2003] [Accepted: 04/27/2004] [Indexed: 11/10/2022]
Abstract
BACKGROUND Leber's congenital amaurosis (LCA) is a severe form of retinal dystrophy. Mutations in the RPE65 gene, which is abundantly expressed in retinal pigment epithelial (RPE) cells, account for approximately 10-15% of LCA cases. In this study we used the high turnover, and rapid breeding and maturation time of the Rpe65-/- knockout mice to assess the efficacy of using rAAV-mediated gene therapy to replace the disrupted RPE65 gene. The potential for rAAV-mediated gene treatment of LCA was then analyzed by determining the pattern of RPE65 expression, the physiological and histological effects that it produced, and any improvement in visual function. METHODS rAAV.RPE65 was injected into the subretinal space of Rpe65-/- knockout mice and control mice. Histological and immunohistological analyses were performed to evaluate any rescue of photoreceptors and to determine longevity and pattern of transgene expression. Electron microscopy was used to examine ultrastructural changes, and electroretinography was used to measure changes in visual function following rAAV.RPE65 injection. RESULTS rAAV-mediated RPE65 expression was detected for up to 18 months post injection. The delivery of rAAV.RPE65 to Rpe65-/- mouse retinas resulted in a transient improvement in the maximum b-wave amplitude under both scotopic and photopic conditions (76% and 59% increase above uninjected controls, respectively) but no changes were observed in a-wave amplitude. However, this increase in b-wave amplitude was not accompanied by any slow down in photoreceptor degeneration or apoptotic cell death. Delivery of rAAV.RPE65 also resulted in a decrease in retinyl ester lipid droplets and an increase in short wavelength cone opsin-positive cells, suggesting that the recovery of RPE65 expression has long-term benefits for retinal health. CONCLUSION This work demonstrated the potential benefits of using the Rpe65-/- mice to study the effects and mechanism of rAAV.RPE65-mediated gene delivery into the retina. Although the functional recovery in this model was not as robust as in the dog model, these experiments provided important clues about the long-term physiological benefits of restoration of RPE65 expression in the retina.
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Affiliation(s)
- Chooi-May Lai
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Meaghan JT Yu
- Department of Molecular Ophthalmology, Lions Eye Institute and The University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Meliha Brankov
- Department of Molecular Ophthalmology, Lions Eye Institute and The University of Western Australia, Perth, Western Australia, 6009, Australia
| | - Nigel L Barnett
- Vision Touch and Hearing Research Centre, School of Biomedical Sciences, University of Queensland, Brisbane, Queensland, 4072, Australia
| | - Xiaohuai Zhou
- Virus Core Facility, Gene Therapy Center, University of North Carolina, North Carolina, 27599, USA
| | - T Michael Redmond
- Laboratory of Retinal Cell and Molecular Biology, National Eye Institute, National Institutes of Health, Bethesda, Maryland, 20892, USA
| | - Kristina Narfstrom
- Vision Science Group, Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri-Columbia, Columbia, Missouri, 65211, USA
| | - P Elizabeth Rakoczy
- Centre for Ophthalmology and Visual Science, The University of Western Australia, Perth, Western Australia, 6009, Australia
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Shen WY, Lai YKY, Lai CM, Rakoczy PE. Impurity of recombinant adeno-associated virus type 2 affects the transduction characteristics following subretinal injection in the rat. Vision Res 2004; 44:339-48. [PMID: 14659960 DOI: 10.1016/j.visres.2003.09.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
We recently reported that different purification methods of recombinant adeno-associated virus type 2 (rAAV2) affect the transduction characteristics following subretinal injection. In this study, we examined the roles of contaminant proteins from the HEK-293 cells and helper adenovirus, inactivation of helper adenovirus and cell stress induced by DNA-damaging agents in rAAV-mediated retinal transduction. Our results showed that contaminating factors/proteins resulting from the helper E1 deleted adenovirus are possibly responsible for efficient RPE transduction. Future studies of these factors will undoubtedly lead to development of new therapeutic approaches to PR- and RPE-specific retinal diseases.
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Affiliation(s)
- Wei-Yong Shen
- Centre for Ophthalmology and Visual Science, The University of Western Australia, 2 Verdun Street, Nedlands, Perth, WA 6009, Australia
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