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Sun D, Sun W, Gao SQ, Lehrer J, Wang H, Hall R, Lu ZR. Intravitreal Delivery of PEGylated-ECO Plasmid DNA Nanoparticles for Gene Therapy of Stargardt Disease. Pharm Res 2024; 41:807-817. [PMID: 38443629 DOI: 10.1007/s11095-024-03679-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2023] [Accepted: 02/18/2024] [Indexed: 03/07/2024]
Abstract
OBJECTIVE Current gene therapy of inherited retinal diseases is achieved mainly by subretinal injection, which is invasive with severe adverse effects. Intravitreal injection is a minimally invasive alternative for gene therapy of inherited retinal diseases. This work explores the efficacy of intravitreal delivery of PEGylated ECO (a multifunctional pH-sensitive amphiphilic amino lipid) plasmid DNA (pGRK1-ABCA4-S/MAR) nanoparticles (PEG-ELNP) for gene therapy of Stargardt disease. METHODS Pigmented Abca4-/- knockout mice received 1 µL of PEG-ELNP solution (200 ng/uL, pDNA concentration) by intravitreal injections at an interval of 1.5 months. The expression of ABCA4 in the retina was determined by RT-PCR and immunohistochemistry at 6 months after the second injection. A2E levels in the treated eyes and untreated controls were determined by HPLC. The safety of treatment was monitored by scanning laser ophthalmoscopy and electroretinogram (ERG). RESULTS PEG-ELNP resulted in significant ABCA4 expression at both mRNA level and protein level at]6 months after 2 intravitreal injections, and a 40% A2E accumulation reduction compared with non-treated controls. The PEG-ELNP also demonstrated excellent safety as shown by scanning laser ophthalmoscopy, and the eye function evaluation from electroretinogram. CONCLUSIONS Intravitreal delivery of the PEG-ELNP of pGRK1-ABCA4-S/MAR is a promising approach for gene therapy of Stargardt Disease, which can also be a delivery platform for gene therapy of other inherited retinal diseases.
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Affiliation(s)
- Da Sun
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, United States
| | - Wenyu Sun
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, United States
| | - Song-Qi Gao
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, United States
| | - Jonathan Lehrer
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, United States
| | - Hong Wang
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, United States
| | - Ryan Hall
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, United States
| | - Zheng-Rong Lu
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH, 44106, United States.
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2
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Choi EH, Suh S, Sears AE, Hołubowicz R, Kedhar SR, Browne AW, Palczewski K. Genome editing in the treatment of ocular diseases. Exp Mol Med 2023; 55:1678-1690. [PMID: 37524870 PMCID: PMC10474087 DOI: 10.1038/s12276-023-01057-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 06/14/2023] [Indexed: 08/02/2023] Open
Abstract
Genome-editing technologies have ushered in a new era in gene therapy, providing novel therapeutic strategies for a wide range of diseases, including both genetic and nongenetic ocular diseases. These technologies offer new hope for patients suffering from previously untreatable conditions. The unique anatomical and physiological features of the eye, including its immune-privileged status, size, and compartmentalized structure, provide an optimal environment for the application of these cutting-edge technologies. Moreover, the development of various delivery methods has facilitated the efficient and targeted administration of genome engineering tools designed to correct specific ocular tissues. Additionally, advancements in noninvasive ocular imaging techniques and electroretinography have enabled real-time monitoring of therapeutic efficacy and safety. Herein, we discuss the discovery and development of genome-editing technologies, their application to ocular diseases from the anterior segment to the posterior segment, current limitations encountered in translating these technologies into clinical practice, and ongoing research endeavors aimed at overcoming these challenges.
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Affiliation(s)
- Elliot H Choi
- Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, CA, USA
| | - Susie Suh
- Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, CA, USA
| | - Avery E Sears
- Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, CA, USA
| | - Rafał Hołubowicz
- Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, CA, USA
| | - Sanjay R Kedhar
- Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, CA, USA
| | - Andrew W Browne
- Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, CA, USA
| | - Krzysztof Palczewski
- Gavin Herbert Eye Institute, Department of Ophthalmology, University of California, Irvine, CA, USA.
- Department of Physiology and Biophysics, University of California, Irvine, CA, USA.
- Department of Chemistry, University of California, Irvine, CA, USA.
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA, USA.
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3
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Preclinical Models of Retinitis Pigmentosa. Methods Mol Biol 2022; 2560:181-215. [PMID: 36481897 DOI: 10.1007/978-1-0716-2651-1_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Retinitis pigmentosa (RP) is the name for a group of phenotypically-related heritable retinal degenerative disorders. Many genes have been implicated as causing variants of RP, and while the clinical phenotypes are remarkably similar, they may differ in age of onset, progression, and severity. Common inheritance patterns for specific genes connected with the development of the disorder include autosomal dominant, autosomal recessive, and X-linked. Modeling the disease in animals and other preclinical systems offers a cost-conscious, ethical, and time-efficient method for studying the disease subtypes. The history of RP models is briefly examined, and both naturally occurring and transgenic preclinical models of RP in many different organisms are discussed. Syndromic forms of RP and models thereof are reviewed as well.
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Covello G, Ibrahim GH, Bacchi N, Casarosa S, Denti MA. Exon Skipping Through Chimeric Antisense U1 snRNAs to Correct Retinitis Pigmentosa GTPase-Regulator ( RPGR) Splice Defect. Nucleic Acid Ther 2022; 32:333-349. [PMID: 35166581 PMCID: PMC9416563 DOI: 10.1089/nat.2021.0053] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Inherited retinal dystrophies are caused by mutations in more than 250 genes, each of them carrying several types of mutations that can lead to different clinical phenotypes. Mutations in Retinitis Pigmentosa GTPase-Regulator (RPGR) cause X-linked Retinitis pigmentosa (RP). A nucleotide substitution in intron 9 of RPGR causes the increase of an alternatively spliced isoform of the mature mRNA, bearing exon 9a (E9a). This introduces a stop codon, leading to truncation of the protein. Aiming at restoring impaired gene expression, we developed an antisense RNA-based therapeutic approach for the skipping of RPGR E9a. We designed a set of specific U1 antisense snRNAs (U1_asRNAs) and tested their efficacy in vitro, upon transient cotransfection with RPGR minigene reporter systems in HEK-293T, 661W, and PC-12 cell lines.
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Affiliation(s)
- Giuseppina Covello
- RNA Biology and Biotechnology Laboratory, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, Trento, Italy
| | - Gehan H Ibrahim
- Department of Medical Biochemistry, Faculty of Medicine, Suez Canal University, Ismailia, Egypt
| | - Niccolò Bacchi
- RNA Biology and Biotechnology Laboratory, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, Trento, Italy
| | - Simona Casarosa
- Neural Development and Regeneration Laboratory, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, Trento, Italy.,Centre for Medical Science - CIS Med, University of Trento, Trento, Italy.,CNR Neuroscience Institute, Pisa, Italy
| | - Michela Alessandra Denti
- RNA Biology and Biotechnology Laboratory, Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, Trento, Italy.,CNR Neuroscience Institute, Pisa, Italy
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5
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Stem cell transplantation as a progressing treatment for retinitis pigmentosa. Cell Tissue Res 2022; 387:177-205. [PMID: 35001210 DOI: 10.1007/s00441-021-03551-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 10/27/2021] [Indexed: 11/02/2022]
Abstract
Retinal degenerative diseases such as retinitis pigmentosa (RP) are of the major causes of vision loss in developed countries. Despite the unclear pathophysiology, treatment methods have been investigated vastly in the past decades. This review article mainly discusses the advances in application of stem cell and progenitor transplantation for retinitis pigmentosa. Stem cell sources such as mesenchymal stem cells, embryonic stem cells, induced pluripotent stem cells, neural stem cells, retinal progenitor cells, and olfactory ensheathing cells are discussed separately in addition to a brief description of two approaches for treatment of early-stage RP, including gene therapy and nutritional therapy.
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6
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Arevalo JF, Al Rashaed S, Alhamad TA, Al Kahtani E, Al-Dhibi HA. Argus II retinal prosthesis for retinitis pigmentosa in the Middle East: The 2015 Pan-American Association of Ophthalmology Gradle Lecture. Int J Retina Vitreous 2021; 7:65. [PMID: 34706764 PMCID: PMC8554988 DOI: 10.1186/s40942-021-00324-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Accepted: 08/26/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND To describe the outcomes of patients with retinitis pigmentosa (RP) who received the Argus II Retinal Prosthesis System. METHODS This retrospective, interventional case series evaluated 10 consecutive patients who received the Argus II retinal implant and underwent visual function tests with the system on and system off. The main outcome measures were safety (the number, seriousness, and relatedness of adverse events), and visual function measured by computer-based objective tests, including square localization (SL) and direction of motion (DOM). Secondary measures included functional vision performance, including orientation and mobility (O&M) tasks. RESULTS There were no intraoperative complications and all prostheses remained implanted at the end of follow up. The mean patient age was 41.3 years; mean duration of the implant in vivo was 2.1 years. One patient had a suture exposure over the coil suture tab and over the inferior case suture tab at 2 years postoperatively, which was managed successfully. One patient developed mild vitreous hemorrhage that resolved spontaneously. One patient developed high intraocular pressure postoperatively due to a tight scleral band (SB) that was managed successfully. Patients performed significantly better with the Argus II system on than off on all tasks. CONCLUSION Patients who received the Argus II had a safety profile out to 4 years post-implantation that was markedly better than that observed in the pre-approval phase of the Argus II. In this population of RP patients, the Argus II retinal prosthesis provided useful visual function over several years that likely translates into improved quality of life. TRIAL REGISTRATION clinicaltrials.gov identifier, NCT00407602.
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Affiliation(s)
- J Fernando Arevalo
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, P. O. Box 7191, Riyadh, 11462, Saudi Arabia.,Retina Division, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Saba Al Rashaed
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, P. O. Box 7191, Riyadh, 11462, Saudi Arabia
| | - Tariq A Alhamad
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, P. O. Box 7191, Riyadh, 11462, Saudi Arabia
| | - Eman Al Kahtani
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, P. O. Box 7191, Riyadh, 11462, Saudi Arabia
| | - Hassan A Al-Dhibi
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, P. O. Box 7191, Riyadh, 11462, Saudi Arabia.
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EPIRETINAL FIBROSIS REMOVAL IN AN ARGUS II-IMPLANTED EYE: Histological Characteristics and Functional Results. Retina 2021; 40:2403-2409. [PMID: 32195788 DOI: 10.1097/iae.0000000000002780] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE 1) To investigate morphologic and histochemical characteristics of an epiretinal fibrosis removed in an Argus II-implanted eye; 2) to evaluate the Argus II function before and after the fibrosis removal, and 3) to compare morphologic and functional data. METHODS Fibrosis, which developed between the Argus II prosthesis and the retina two years after implant, was surgically removed. Its morphologic and histochemical characteristics were evaluated both in light and transmission electron microscopy, with special stains and immunohistochemistry. The Argus II function was evaluated during the follow-up before surgical removal and 1 month later. RESULTS Fibrosis was successfully removed. It was composed of a fibrotic tissue with spindle cells arranged in nodular aggregates with a symmetric distribution, mixed with an inflammatory infiltrate. Extra- and intracellular, irregular, small iron particles were found and confirmed ultrastructural characterization with degenerative cellular changes. The repositioned Argus II restored, and its function was partially nearly to normal values 1 month after surgery. CONCLUSION Fibrosis can develop between the Argus II and the retina with increasing reduced function. Morphologic characteristics of the removed fibrosis suggested a pathogenesis based on an inflammatory process involved in a foreign body reaction with progressing connective tissue deposition leading to sclerosis. Adequate clinical follow-up is critical to successful removal of the fibrosis with reactivation of the Argus II function.
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8
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Fernandez-Gonzalez P, Mas-Sanchez A, Garriga P. Polyphenols and Visual Health: Potential Effects on Degenerative Retinal Diseases. Molecules 2021; 26:3407. [PMID: 34199888 PMCID: PMC8200069 DOI: 10.3390/molecules26113407] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/01/2021] [Accepted: 06/02/2021] [Indexed: 12/26/2022] Open
Abstract
Dietary polyphenols are a group of natural compounds that have been proposed to have beneficial effects on human health. They were first known for their antioxidant properties, but several studies over the years have shown that these compounds can exert protective effects against chronic diseases. Nonetheless, the mechanisms underlying these potential benefits are still uncertain and contradictory effects have been reported. In this review, we analyze the potential effects of polyphenol compounds on some visual diseases, with a special focus on retinal degenerative diseases. Current effective therapies for the treatment of such retinal diseases are lacking and new strategies need to be developed. For this reason, there is currently a renewed interest in finding novel ligands (or known ligands with previously unexpected features) that could bind to retinal photoreceptors and modulate their molecular properties. Some polyphenols, especially flavonoids (e.g., quercetin and tannic acid), could attenuate light-induced receptor damage and promote visual health benefits. Recent evidence suggests that certain flavonoids could help stabilize the correctly folded conformation of the visual photoreceptor protein rhodopsin and offset the deleterious effect of retinitis pigmentosa mutations. In this regard, certain polyphenols, like the flavonoids mentioned before, have been shown to improve the stability, expression, regeneration and folding of rhodopsin mutants in experimental in vitro studies. Moreover, these compounds appear to improve the integration of the receptor into the cell membrane while acting against oxidative stress at the same time. We anticipate that polyphenol compounds can be used to target visual photoreceptor proteins, such as rhodopsin, in a way that has only been recently proposed and that these can be used in novel approaches for the treatment of retinal degenerative diseases like retinitis pigmentosa; however, studies in this field are limited and further research is needed in order to properly characterize the effects of these compounds on retinal degenerative diseases through the proposed mechanisms.
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Affiliation(s)
| | | | - Pere Garriga
- Grup de Biotecnologia Molecular i Industrial, Centre de Biotecnologia Molecular, Departament d’Enginyeria Química, Universitat Politècnica de Catalunya, Edifici Gaia, 08222 Terrassa, Spain; (P.F.-G.); (A.M.-S.)
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9
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Razzaghi N, Fernandez-Gonzalez P, Mas-Sanchez A, Vila-Julià G, Perez JJ, Garriga P. Effect of Sodium Valproate on the Conformational Stability of the Visual G Protein-Coupled Receptor Rhodopsin. Molecules 2021; 26:molecules26103032. [PMID: 34069614 PMCID: PMC8160834 DOI: 10.3390/molecules26103032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/13/2021] [Accepted: 05/17/2021] [Indexed: 12/29/2022] Open
Abstract
Rhodopsin is the G protein-coupled receptor of rod photoreceptor cells that mediates vertebrate vision at low light intensities. Mutations in rhodopsin cause inherited retinal degenerative diseases such as retinitis pigmentosa. Several therapeutic strategies have attempted to address and counteract the deleterious effect of rhodopsin mutations on the conformation and function of this photoreceptor protein, but none has been successful in efficiently preventing retinal degeneration in humans. These approaches include, among others, the use of small molecules, known as pharmacological chaperones, that bind to the receptor stabilizing its proper folded conformation. Valproic acid, in its sodium valproate form, has been used as an anticonvulsant in epileptic patients and in the treatment of several psychiatric disorders. More recently, this compound has been tested as a potential therapeutic agent for the treatment of retinal degeneration associated with retinitis pigmentosa caused by rhodopsin mutations. We now report on the effect of sodium valproate on the conformational stability of heterologously expressed wild-type rhodopsin and a rhodopsin mutant, I307N, which has been shown to be an appropriate model for studying retinal degeneration in mice. We found no sign of enhanced stability for the dark inactive conformation of the I307N mutant. Furthermore, the photoactivated conformation of the mutant appears to be destabilized by sodium valproate as indicated by a faster decay of its active conformation. Therefore, our results support a destabilizing effect of sodium valproate on rhodopsin I307N mutant associated with retinal degeneration. These findings, at the molecular level, agree with recent clinical studies reporting negative effects of sodium valproate on the visual function of retinitis pigmentosa patients.
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Affiliation(s)
- Neda Razzaghi
- Grup de Biotecnologia Molecular i Industrial, Centre de Biotecnologia Molecular, Departament d’Enginyeria Química, Universitat Politècnica de Catalunya-Barcelona Tech, Edifici Gaia, Rambla de Sant Nebridi 22, 08222 Terrassa, Spain; (N.R.); (P.F.-G.); (A.M.-S.)
| | - Pol Fernandez-Gonzalez
- Grup de Biotecnologia Molecular i Industrial, Centre de Biotecnologia Molecular, Departament d’Enginyeria Química, Universitat Politècnica de Catalunya-Barcelona Tech, Edifici Gaia, Rambla de Sant Nebridi 22, 08222 Terrassa, Spain; (N.R.); (P.F.-G.); (A.M.-S.)
| | - Aina Mas-Sanchez
- Grup de Biotecnologia Molecular i Industrial, Centre de Biotecnologia Molecular, Departament d’Enginyeria Química, Universitat Politècnica de Catalunya-Barcelona Tech, Edifici Gaia, Rambla de Sant Nebridi 22, 08222 Terrassa, Spain; (N.R.); (P.F.-G.); (A.M.-S.)
| | - Guillem Vila-Julià
- Grup de Biotecnologia Molecular i Industrial, Centre de Biotecnologia Molecular, Departament d’Enginyeria Química, Universitat Politècnica de Catalunya-Barcelona Tech., Avinguda Diagonal, 647, 08028 Barcelona, Spain; (G.V.-J.); (J.J.P.)
| | - Juan Jesus Perez
- Grup de Biotecnologia Molecular i Industrial, Centre de Biotecnologia Molecular, Departament d’Enginyeria Química, Universitat Politècnica de Catalunya-Barcelona Tech., Avinguda Diagonal, 647, 08028 Barcelona, Spain; (G.V.-J.); (J.J.P.)
| | - Pere Garriga
- Grup de Biotecnologia Molecular i Industrial, Centre de Biotecnologia Molecular, Departament d’Enginyeria Química, Universitat Politècnica de Catalunya-Barcelona Tech, Edifici Gaia, Rambla de Sant Nebridi 22, 08222 Terrassa, Spain; (N.R.); (P.F.-G.); (A.M.-S.)
- Correspondence:
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10
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De La Camara CMF, Cehajic-Kapetanovic J, MacLaren RE. RPGR gene therapy presents challenges in cloning the coding sequence. Expert Opin Biol Ther 2020; 20:63-71. [PMID: 31612744 PMCID: PMC7104355 DOI: 10.1080/14712598.2020.1680635] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Introduction: Currently, there are three Phase I/II clinical trials based on gene therapy ongoing to test different AAV.RPGR or deleted RPGR vectors on patients affected by X-linked retinitis pigmentosa. These three vectors differ in the adeno-associated viral (AAV) vector capsid used, and the coding sequences: two contain codon optimized versions of RPGR which give the full-length protein, whilst the third uses a wild-type sequence that contains a large deletion encoding part of the functional domain of the RPGR protein.Areas covered: This review approaches the different studies that have led to the initiation of three different clinical trials for RPGR related X-linked retinitis pigmentosa.Expert opinion: The development of a gene therapy vector to deliver a normal copy of the RPGR gene into the photoreceptors has presented a challenge for the scientific community. The instability of its sequence and the fact that its function is not well understood can lead to the production of a nonfunctional or deleterious protein for the human retina. Since the RPGR protein undergoes post-translational glutamylation in the protein domain that may be particularly affected by gene instability, a functional assay of glutamylation is essential to verify the correct coding sequence.
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Affiliation(s)
- Cristina Martinez-Fernandez De La Camara
- Department of Clinical Neurosciences, Nuffield Laboratory of Ophthalmology, University of Oxford, John Radcliffe Hospital, Headley Way, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Trust, John Radcliffe Hospital, Headley Way, UK
| | - Jasmina Cehajic-Kapetanovic
- Department of Clinical Neurosciences, Nuffield Laboratory of Ophthalmology, University of Oxford, John Radcliffe Hospital, Headley Way, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Trust, John Radcliffe Hospital, Headley Way, UK
| | - Robert E. MacLaren
- Department of Clinical Neurosciences, Nuffield Laboratory of Ophthalmology, University of Oxford, John Radcliffe Hospital, Headley Way, UK
- Oxford Eye Hospital, Oxford University Hospitals NHS Trust, John Radcliffe Hospital, Headley Way, UK
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11
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Pfeiffer RL, Marc RE, Jones BW. Persistent remodeling and neurodegeneration in late-stage retinal degeneration. Prog Retin Eye Res 2020; 74:100771. [PMID: 31356876 PMCID: PMC6982593 DOI: 10.1016/j.preteyeres.2019.07.004] [Citation(s) in RCA: 88] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/15/2019] [Accepted: 07/18/2019] [Indexed: 02/06/2023]
Abstract
Retinal remodeling is a progressive series of negative plasticity revisions that arise from retinal degeneration, and are seen in retinitis pigmentosa, age-related macular degeneration and other forms of retinal disease. These processes occur regardless of the precipitating event leading to degeneration. Retinal remodeling then culminates in a late-stage neurodegeneration that is indistinguishable from progressive central nervous system (CNS) proteinopathies. Following long-term deafferentation from photoreceptor cell death in humans, and long-lived animal models of retinal degeneration, most retinal neurons reprogram, then die. Glial cells reprogram into multiple anomalous metabolic phenotypes. At the same time, survivor neurons display degenerative inclusions that appear identical to progressive CNS neurodegenerative disease, and contain aberrant α-synuclein (α-syn) and phosphorylated α-syn. In addition, ultrastructural analysis indicates a novel potential mechanism for misfolded protein transfer that may explain how proteinopathies spread. While neurodegeneration poses a barrier to prospective retinal interventions that target primary photoreceptor loss, understanding the progression and time-course of retinal remodeling will be essential for the establishment of windows of therapeutic intervention and appropriate tuning and design of interventions. Finally, the development of protein aggregates and widespread neurodegeneration in numerous retinal degenerative diseases positions the retina as a ideal platform for the study of proteinopathies, and mechanisms of neurodegeneration that drive devastating CNS diseases.
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Affiliation(s)
- Rebecca L Pfeiffer
- Dept of Ophthalmology, Moran Eye Center, University of Utah, Salt Lake City, UT, USA; Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, USA.
| | - Robert E Marc
- Dept of Ophthalmology, Moran Eye Center, University of Utah, Salt Lake City, UT, USA; Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, USA
| | - Bryan William Jones
- Dept of Ophthalmology, Moran Eye Center, University of Utah, Salt Lake City, UT, USA; Interdepartmental Program in Neuroscience, University of Utah, Salt Lake City, UT, USA.
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12
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Lunghi C, Galli-Resta L, Binda P, Cicchini GM, Placidi G, Falsini B, Morrone MC. Visual Cortical Plasticity in Retinitis Pigmentosa. Invest Ophthalmol Vis Sci 2019; 60:2753-2763. [PMID: 31247082 PMCID: PMC6746622 DOI: 10.1167/iovs.18-25750] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Purpose Retinitis pigmentosa is a family of genetic diseases inducing progressive photoreceptor degeneration. There is no cure for retinitis pigmentosa, but prospective therapeutic strategies are aimed at restoring or substituting retinal input. Yet, it is unclear whether the visual cortex of retinitis pigmentosa patients retains plasticity to react to the restored visual input. Methods To investigate short-term visual cortical plasticity in retinitis pigmentosa, we tested the effect of short-term (2 hours) monocular deprivation on sensory ocular dominance (measured with binocular rivalry) in a group of 14 patients diagnosed with retinitis pigmentosa with a central visual field sparing greater than 20° in diameter. Results After deprivation most patients showed a perceptual shift in ocular dominance in favor of the deprived eye (P < 0.001), as did control subjects, indicating a level of visual cortical plasticity in the normal range. The deprivation effect correlated negatively with visual acuity (r = −0.63, P = 0.015), and with the amplitude of the central 18° focal electroretinogram (r = −0.68, P = 0.015) of the deprived eye, revealing that in retinitis pigmentosa stronger visual impairment is associated with higher plasticity. Conclusions Our results provide a new tool to assess the ability of retinitis pigmentosa patients to adapt to altered visual inputs, and suggest that in retinitis pigmentosa the adult brain has sufficient short-term plasticity to benefit from prospective therapies.
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Affiliation(s)
- Claudia Lunghi
- Laboratoire des systèmes perceptifs, Département d'études Cognitives, École Normale Supérieure, PSL University, CNRS, Paris, France.,Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | | | - Paola Binda
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.,Institute of Neuroscience CNR, Pisa, Italy
| | | | - Giorgio Placidi
- Department of Ophthalmology, Policlinico Gemelli, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Benedetto Falsini
- Department of Ophthalmology, Policlinico Gemelli, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Maria Concetta Morrone
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy.,IRCCS Stella Maris, Calambrone (Pisa), Italy
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13
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Rizzo S, Cinelli L, Finocchio L, Tartaro R, Santoro F, Gregori NZ. Assessment of Postoperative Morphologic Retinal Changes by Optical Coherence Tomography in Recipients of an Electronic Retinal Prosthesis Implant. JAMA Ophthalmol 2019; 137:272-278. [PMID: 30605209 PMCID: PMC6439717 DOI: 10.1001/jamaophthalmol.2018.6375] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 11/09/2018] [Indexed: 01/10/2023]
Abstract
Importance The postoperative retinal changes at the interface between an implant electrode array and the retina and whether these anatomic changes have an association with the patient visual performance are unknown. Objective To report morphologic changes in recipients of an Argus II Retinal Prosthesis. Design, Setting, and Participants This consecutive, noncomparative case series study included a retrospective review of the preoperative and postoperative optical coherence tomography of 33 eyes among 33 individuals who underwent Argus II Retinal Prosthesis System implantation between October 28, 2011, and June 8, 2017, at 2 different centers, by the same surgeon (S.R.). Thirteen patients received an implant at Azienda Ospedaliero Universitaria Pisana, Pisa, Italy, between October 28, 2011, and October 27, 2014, and 20 patients underwent surgery at Azienda Ospedaliera Universitaria Careggi, Florence, Italy, between December 20, 2014, and June 8, 2017. Patients were excluded if they did not reach the 6-month follow-up. Main Outcomes and Measures All patients were evaluated before surgery, during the first postoperative day, and at 1, 3, 6, 12, and 24 months (subsequently once a year, except for patient-related adverse events), with a comprehensive ophthalmic examination, retinal fundus photography, spectral-domain optical coherence tomography, and visual function tests to evaluate the stability or improvement of their visual performance. Results Of the 20 patients included in the analysis, all were of white race/ethnicity, 12 (60%) were male, and the mean (SD) age was 57.4 (11.6) years. Optical coherence tomography revealed the development of a fibrosislike hyperreflective tissue limited at the interface between the array and retina in 10 eyes (50%). In 9 of 10 patients (90%), fibrosis evolved and progressed to retinal schisis. Despite the development of the fibrosis and schisis, there was no deterioration in the patient's visual performance evaluated prospectively with visual function tests (square localization and direction of motion). Conclusions and Relevance Optical coherence tomography may be used to observe the retinal anatomic changes in patients with an Argus II Prothesis. This analysis revealed the development of a fibrosislike hyperreflective tissue limited at the interface between array and retina that progressed to retinal schisis but with no deterioration in the patients' visual performance.
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Affiliation(s)
- Stanislao Rizzo
- Azienda Ospedaliera Universitaria Careggi, Dipartimento di Medicina e Chirurgia Traslazionale, University of Florence, Florence, Italy
| | - Laura Cinelli
- Azienda Ospedaliera Universitaria Careggi, Dipartimento di Medicina e Chirurgia Traslazionale, University of Florence, Florence, Italy
| | - Lucia Finocchio
- Azienda Ospedaliera Universitaria Careggi, Dipartimento di Medicina e Chirurgia Traslazionale, University of Florence, Florence, Italy
| | - Ruggero Tartaro
- Azienda Ospedaliera Universitaria Careggi, Dipartimento di Medicina e Chirurgia Traslazionale, University of Florence, Florence, Italy
| | - Francesca Santoro
- Azienda Ospedaliera Universitaria Careggi, Dipartimento di Medicina e Chirurgia Traslazionale, University of Florence, Florence, Italy
| | - Ninel Z. Gregori
- Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, Florida
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Flavonoid allosteric modulation of mutated visual rhodopsin associated with retinitis pigmentosa. Sci Rep 2017; 7:11167. [PMID: 28894166 PMCID: PMC5593859 DOI: 10.1038/s41598-017-11391-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 08/22/2017] [Indexed: 11/08/2022] Open
Abstract
Dietary flavonoids exhibit many biologically-relevant functions and can potentially have beneficial effects in the treatment of pathological conditions. In spite of its well known antioxidant properties, scarce structural information is available on the interaction of flavonoids with membrane receptors. Advances in the structural biology of a specific class of membrane receptors, the G protein-coupled receptors, have significantly increased our understanding of drug action and paved the way for developing improved therapeutic approaches. We have analyzed the effect of the flavonoid quercetin on the conformation, stability and function of the G protein-coupled receptor rhodopsin, and the G90V mutant associated with the retinal degenerative disease retinitis pigmentosa. By using a combination of experimental and computational methods, we suggest that quercetin can act as an allosteric modulator of opsin regenerated with 9-cis-retinal and more importantly, that this binding has a positive effect on the stability and conformational properties of the G90V mutant associated with retinitis pigmentosa. These results open new possibilities to use quercetin and other flavonoids, in combination with specific retinoids like 9-cis-retinal, for the treatment of retinal degeneration associated with retinitis pigmentosa. Moreover, the use of flavonoids as allosteric modulators may also be applicable to other members of the G protein-coupled receptors superfamily.
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15
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Beyeler M, Rokem A, Boynton GM, Fine I. Learning to see again: biological constraints on cortical plasticity and the implications for sight restoration technologies. J Neural Eng 2017; 14:051003. [PMID: 28612755 DOI: 10.1088/1741-2552/aa795e] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The 'bionic eye'-so long a dream of the future-is finally becoming a reality with retinal prostheses available to patients in both the US and Europe. However, clinical experience with these implants has made it apparent that the visual information provided by these devices differs substantially from normal sight. Consequently, the ability of patients to learn to make use of this abnormal retinal input plays a critical role in whether or not some functional vision is successfully regained. The goal of the present review is to summarize the vast basic science literature on developmental and adult cortical plasticity with an emphasis on how this literature might relate to the field of prosthetic vision. We begin with describing the distortion and information loss likely to be experienced by visual prosthesis users. We then define cortical plasticity and perceptual learning, and describe what is known, and what is unknown, about visual plasticity across the hierarchy of brain regions involved in visual processing, and across different stages of life. We close by discussing what is known about brain plasticity in sight restoration patients and discuss biological mechanisms that might eventually be harnessed to improve visual learning in these patients.
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Affiliation(s)
- Michael Beyeler
- Department of Psychology, University of Washington, Seattle, WA, United States of America. Institute for Neuroengineering, University of Washington, Seattle, WA, United States of America. eScience Institute, University of Washington, Seattle, WA, United States of America
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16
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Jeter PE, Rozanski C, Massof R, Adeyemo O, Dagnelie G. Development of the Ultra-Low Vision Visual Functioning Questionnaire (ULV-VFQ). Transl Vis Sci Technol 2017; 6:11. [PMID: 28573075 PMCID: PMC5450923 DOI: 10.1167/tvst.6.3.11] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 01/27/2017] [Indexed: 11/30/2022] Open
Abstract
Purpose To develop and psychometrically evaluate a visual functioning questionnaire (VFQ) in an ultra-low vision (ULV) population. Methods Questionnaire items, based on visual activities self-reported by a ULV population, were categorized by functional visual domain (e.g., mobility) and visual aspect (e.g., contrast) to ensure a representative distribution. In Round 1, an initial set of 149 items was generated and administered to 90 participants with ULV (visual acuity [VA] ≤ 20/500; mean [SD] age 61 [15] years), including six patients with a retinal implant. Psychometric properties were evaluated through Rasch analysis and a revised set (150 items) was administered to 80 participants in Round 2. Results In Round 1, the person measure distribution (range, 8.6 logits) was centered at −1.50 logits relative to the item measures. In Round 2, the person measure distribution (range, 9.5 logits) was centered at −0.86 relative to the item mean. The reliability index in both rounds was 0.97 for Items and 0.99 for Persons. Infit analysis showed four underfit items in Round 1, five underfit items in Round 2 with a z-score greater than 4 cutoff. Principal component analysis on the residuals found 69.9% explained variance; the largest component in the unexplained variance was less than 3%. Conclusions The ULV-VFQ, developed with content generated from a ULV population, showed excellent psychometric properties as well as superior measurement validity in a ULV population. Translational Relevance The ULV-VFQ, part of the Prosthetic Low Vision Rehabilitation (PLoVR) development program, is a new VFQ developed for assessment of functional vision in ULV populations.
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Affiliation(s)
- Pamela E Jeter
- Lions Vision Center, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Collin Rozanski
- Lions Vision Center, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Robert Massof
- Lions Vision Center, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Olukemi Adeyemo
- Lions Vision Center, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Gislin Dagnelie
- Lions Vision Center, Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Peripherin-2 and Rom-1 have opposing effects on rod outer segment targeting of retinitis pigmentosa-linked peripherin-2 mutants. Sci Rep 2017; 7:2321. [PMID: 28539581 PMCID: PMC5443838 DOI: 10.1038/s41598-017-02514-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 04/12/2017] [Indexed: 12/30/2022] Open
Abstract
Mutations in the photoreceptor outer segment (OS) specific peripherin-2 lead to autosomal dominant retinitis pigmentosa (adRP). By contrast, mutations in the peripherin-2 homolog Rom-1 cause digenic RP in combination with certain heterozygous mutations in peripherin-2. The mechanisms underlying the differential role of peripherin-2 and Rom-1 in RP pathophysiology remained elusive so far. Here, focusing on two adRP-linked peripherin-2 mutants, P210L and C214S, we analyzed the binding characteristics, protein assembly, and rod OS targeting of wild type (perWT), mutant peripherin-2 (perMT), or Rom-1 complexes, which can be formed in patients heterozygous for peripherin-2 mutations. Both mutants are misfolded and lead to decreased binding to perWT and Rom-1. Furthermore, both mutants are preferentially forming non-covalent perMT-perMT, perWT-perMT, and Rom-1-perMT dimers. However, only perWT-perMT, but not perMT-perMT or Rom-1-perMT complexes could be targeted to murine rod OS. Our study provides first evidence that non-covalent perWT-perMT dimers can be targeted to rod OS. Finally, our study unravels unexpected opposing roles of perWT and Rom-1 in rod OS targeting of adRP-linked peripherin-2 mutants and suggests a new treatment strategy for the affected individuals.
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18
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Sharif W, Sharif Z. Leber's congenital amaurosis and the role of gene therapy in congenital retinal disorders. Int J Ophthalmol 2017; 10:480-484. [PMID: 28393043 DOI: 10.18240/ijo.2017.03.24] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 08/19/2016] [Indexed: 11/23/2022] Open
Abstract
Leber's congenital amaurosis (LCA) and recent gene therapy advancement for treating inherited retinopathies were extensive literature reviewed using MEDLINE, PubMed and EMBASE. Adeno-associated viral vectors were the most utilised vectors for ocular gene therapy. Cone photoreceptor cells might use an alternate pathway which was not reliant of the retinal pigment epithelium (RPE) derived retinoid isomerohydrolase (RPE65) to access the 11-cis retinal dehydechromophore. Research efforts dedicated on the progression of a gene-based therapy for the treatment of LCA2. Such gene therapy approaches were extremely successful in canine, porcine and rodent LCA2 models. The recombinant AAV2.hRPE65v2 adeno-associated vector contained the RPE65 cDNA and was replication deficient. Its in vitro injection in target cells induced RPE65 protein production. The gene therapy trials that were so far conducted for inherited retinopathies have generated promising results. Phase I clinical trials to cure LCA and choroideremia demonstrated that adeno-associated viral vectors containing RPE genes and photoreceptors respectively, could be successfully administered to inherited retinopathy patients. A phase III trial is presently ongoing and if successful, it will lead the way to additional gene therapy attempts to cure monogenic, inherited retinopathies.
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Affiliation(s)
- Walid Sharif
- Department of Ophthalmology Birmingham & Midland Eye Centre, City Hospital NHS Trust, Birmingham B18 7QH, UK
| | - Zuhair Sharif
- Institute of Ophthalmology, University College London 11-43 Bath St, London EC1V 9EL, UK
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19
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Deshpande R, Save P, Deshpande M, Shegunashi M, Chougule M, Khandekar R. Validity and cost-effectiveness of cone adaptation test as a screening tool to detect retinitis pigmentosa. Oman J Ophthalmol 2016; 9:135-138. [PMID: 27843226 PMCID: PMC5084494 DOI: 10.4103/0974-620x.192262] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Background: The cone adaptation test is to detect retinitis pigmentosa (RP) cases confirmed by electroretinogram (ERG). We present the validity and cost-effectiveness of cone adaptation test as a screening tool for detecting RP. Methods: This cross-sectional study was conducted between November 2013 and December 2013. All RP cases diagnosed by ophthalmologists of H. V. Desai Eye Hospital in the last 5 years were participated in this study. The cone adaptation test was done in photopic and scotopic illumination. Failed test means 10 s or more to complete the test under scotopic illumination. A technician who was masked for cone adaptation test finding carried out ERG. Demographics, symptoms, and history of treatment were inquired. Those with flat ERG wave in scotopic condition and corresponding clinical findings were defined as having RP. Sensitivity, specificity, and false-positive and false-negative parameters of validity were estimated. The unit cost of performing test and ERG was calculated. Results: All 32 RP patients (28 male, age median 23.5 ± 14.5 years) had a vision more than 6/60 and flat wave in ERG under mesopic/scotopic illumination. Thirty-one participants failed cone adaptation test. The sensitivity was 31/32 × 100 = 97%. The specificity was 100%. There was no false-positive case. Consanguinity rate among parents was 43%. The cost of testing one child using “cone adaptation test kit” was 2.5 US $. The unit cost of diagnosing RP using ERG was 10 US $. Conclusion: Cone adaptation is a valid and cost-effective screening tool test for RP. The consanguinity rate among parents of an RP patient was high.
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Affiliation(s)
- Rahul Deshpande
- Department of Retina, H. V. Desai Eye Hospital, Pune, Maharashtra, India
| | - Prajakta Save
- Department of Retina, H. V. Desai Eye Hospital, Pune, Maharashtra, India
| | - Madan Deshpande
- Department of Retina, H. V. Desai Eye Hospital, Pune, Maharashtra, India
| | - Mahadev Shegunashi
- Department of Retina, H. V. Desai Eye Hospital, Pune, Maharashtra, India
| | - Marium Chougule
- Department of Retina, H. V. Desai Eye Hospital, Pune, Maharashtra, India
| | - Rajiv Khandekar
- Department of Research, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
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20
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Castaldi E, Cicchini GM, Cinelli L, Biagi L, Rizzo S, Morrone MC. Visual BOLD Response in Late Blind Subjects with Argus II Retinal Prosthesis. PLoS Biol 2016; 14:e1002569. [PMID: 27780207 PMCID: PMC5079588 DOI: 10.1371/journal.pbio.1002569] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 09/19/2016] [Indexed: 11/19/2022] Open
Abstract
Retinal prosthesis technologies require that the visual system downstream of the retinal circuitry be capable of transmitting and elaborating visual signals. We studied the capability of plastic remodeling in late blind subjects implanted with the Argus II Retinal Prosthesis with psychophysics and functional MRI (fMRI). After surgery, six out of seven retinitis pigmentosa (RP) blind subjects were able to detect high-contrast stimuli using the prosthetic implant. However, direction discrimination to contrast modulated stimuli remained at chance level in all of them. No subject showed any improvement of contrast sensitivity in either eye when not using the Argus II. Before the implant, the Blood Oxygenation Level Dependent (BOLD) activity in V1 and the lateral geniculate nucleus (LGN) was very weak or absent. Surprisingly, after prolonged use of Argus II, BOLD responses to visual input were enhanced. This is, to our knowledge, the first study tracking the neural changes of visual areas in patients after retinal implant, revealing a capacity to respond to restored visual input even after years of deprivation.
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Affiliation(s)
- E. Castaldi
- Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | | | - L. Cinelli
- Azienda Ospedaliero-Universitaria Careggi, SOD Oculistica, Florence, Italy
| | - L. Biagi
- Stella Maris Scientific Institute, Pisa, Italy
| | - S. Rizzo
- Azienda Ospedaliero-Universitaria Careggi, SOD Oculistica, Florence, Italy
| | - M. C. Morrone
- Department of Translational Research on New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
- Stella Maris Scientific Institute, Pisa, Italy
- * E-mail:
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21
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Jacobson SG, McGuigan DB, Sumaroka A, Roman AJ, Gruzensky ML, Sheplock R, Palma J, Schwartz SB, Aleman TS, Cideciyan AV. Complexity of the Class B Phenotype in Autosomal Dominant Retinitis Pigmentosa Due to Rhodopsin Mutations. Invest Ophthalmol Vis Sci 2016; 57:4847-4858. [PMID: 27654411 PMCID: PMC5032913 DOI: 10.1167/iovs.16-19890] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Purpose Previously, patients with RHO mutations and a class A phenotype were found to have severe early-onset loss of rod function, whereas patients with a class B phenotype retained rod function at least in certain retinal regions. Here class B patients were studied at different disease stages to understand the topographic details of the phenotype in preparation for therapies of this regionalized retinopathy. Methods A cohort of patients with RHO mutations and class B phenotype (n = 28; ages 10–80 years) were studied with rod and cone perimetry and optical coherence tomography (OCT). Results At least three components of the phenotype were identified in these cross-sectional studies. Patients could have hemifield dysfunction, pericentral loss of function, or a diffuse rod sensitivity loss across the visual field. Combinations of these different patterns were also found. Colocalized photoreceptor layer thicknesses were in agreement with the psychophysical results. Conclusions These disorders with regional retinal variation of severity require pre-evaluations before enrollment into clinical trials to seek answers to questions about where in the retina would be appropriate to deliver focal treatments, and, for retina-wide treatment strategies, where in the retina should be monitored for therapeutic efficacy (or safety).
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Affiliation(s)
- Samuel G Jacobson
- Scheie Eye Institute Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - David B McGuigan
- Scheie Eye Institute Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Alexander Sumaroka
- Scheie Eye Institute Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Alejandro J Roman
- Scheie Eye Institute Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Michaela L Gruzensky
- Scheie Eye Institute Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Rebecca Sheplock
- Scheie Eye Institute Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Judy Palma
- Scheie Eye Institute Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Sharon B Schwartz
- Scheie Eye Institute Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Tomas S Aleman
- Scheie Eye Institute Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Artur V Cideciyan
- Scheie Eye Institute Department of Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States
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22
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da Cruz L, Dorn JD, Humayun MS, Dagnelie G, Handa J, Barale PO, Sahel JA, Stanga PE, Hafezi F, Safran AB, Salzmann J, Santos A, Birch D, Spencer R, Cideciyan AV, de Juan E, Duncan JL, Eliott D, Fawzi A, Olmos de Koo LC, Ho AC, Brown G, Haller J, Regillo C, Del Priore LV, Arditi A, Greenberg RJ. Five-Year Safety and Performance Results from the Argus II Retinal Prosthesis System Clinical Trial. Ophthalmology 2016; 123:2248-54. [PMID: 27453256 DOI: 10.1016/j.ophtha.2016.06.049] [Citation(s) in RCA: 212] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 06/04/2016] [Accepted: 06/17/2016] [Indexed: 12/16/2022] Open
Abstract
PURPOSE The Argus II Retinal Prosthesis System (Second Sight Medical Products, Inc, Sylmar, CA) was developed to restore some vision to patients blind as a result of retinitis pigmentosa (RP) or outer retinal degeneration. A clinical trial was initiated in 2006 to study the long-term safety and efficacy of the Argus II System in patients with bare or no light perception resulting from end-stage RP. DESIGN Prospective, multicenter, single-arm clinical trial. Within-patient controls included the nonimplanted fellow eye and patients' native residual vision compared with their vision with the Argus II. PARTICIPANTS Thirty participants in 10 centers in the United States and Europe. METHODS The worse-seeing eye of blind patients was implanted with the Argus II. Patients wore glasses mounted with a small camera and a video processor that converted images into stimulation patterns sent to the electrode array on the retina. MAIN OUTCOME MEASURES The primary outcome measures were safety (the number, seriousness, and relatedness of adverse events) and visual function, as measured by 3 computer-based, objective tests. Secondary measures included functional vision performance on objectively scored real-world tasks. RESULTS Twenty-four of 30 patients remained implanted with functioning Argus II Systems at 5 years after implantation. Only 1 additional serious adverse event was experienced after the 3-year time point. Patients performed significantly better with the Argus II on than off on all visual function tests and functional vision tasks. CONCLUSIONS The 5-year results of the Argus II trial support the long-term safety profile and benefit of the Argus II System for patients blind as a result of RP. The Argus II is the first and only retinal implant to have market approval in the European Economic Area, the United States, and Canada.
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Affiliation(s)
- Lyndon da Cruz
- Department of Vitreoretinal Surgery, Moorfields Eye Hospital, NHS Foundation Trust, NIHR Moorfields Biomedical Research Centre, London, United Kingdom and Department of Brain Science, University College London (UCL)
| | - Jessy D Dorn
- Second Sight Medical Products, Inc, Sylmar, California.
| | - Mark S Humayun
- University of Southern California, Los Angeles, California
| | - Gislin Dagnelie
- Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland
| | - James Handa
- Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland
| | | | - José-Alain Sahel
- Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France; Sorbonne Universities-UPMC Paris-6, and Institut de la Vision, Paris, France; Rothschild Ophthalmology Foundation, Paris, France
| | - Paulo E Stanga
- Manchester Royal Eye Hospital, Manchester Vision Regeneration (MVR) Laboratory at NIHR/Wellcome Trust Manchester CRF, and Manchester Academic Health Science Centre and Centre for Ophthalmology and Vision Research, Institute of Human Development, University of Manchester, Manchester, United Kingdom
| | - Farhad Hafezi
- University of Southern California, Los Angeles, California; ELZA Institute, Zurich, Switzerland; Hôpitaux Universitaires de Genève, Geneva, Switzerland
| | - Avinoam B Safran
- Sorbonne Universities-UPMC Paris-6, and Institut de la Vision, Paris, France; Hôpitaux Universitaires de Genève, Geneva, Switzerland
| | - Joel Salzmann
- Hôpitaux Universitaires de Genève, Geneva, Switzerland
| | - Arturo Santos
- Centro de Retina Medica y Quirúrgica, SC, and Tecnologico de Monterrey, Guadalajara, Mexico
| | - David Birch
- Retina Foundation of the Southwest, Dallas, Texas
| | | | - Artur V Cideciyan
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Eugene de Juan
- University of California, San Francisco, San Francisco, California
| | - Jacque L Duncan
- University of California, San Francisco, San Francisco, California
| | - Dean Eliott
- University of Southern California, Los Angeles, California; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts
| | - Amani Fawzi
- University of Southern California, Los Angeles, California; Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | | | - Allen C Ho
- Wills Eye Hospital, Philadelphia, Pennsylvania
| | - Gary Brown
- Wills Eye Hospital, Philadelphia, Pennsylvania
| | - Julia Haller
- Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland; Wills Eye Hospital, Philadelphia, Pennsylvania
| | | | - Lucian V Del Priore
- Columbia University, New York, and Storm Eye Institute, Charleston, South Carolina
| | - Aries Arditi
- Lighthouse Guild, New York, and Visibility Metrics, LLC, Chappaqua, New York
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Shu Y, Tao Y, Wang Z, Tang Y, Li H, Dai P, Gao G, Chen ZY. Identification of Adeno-Associated Viral Vectors That Target Neonatal and Adult Mammalian Inner Ear Cell Subtypes. Hum Gene Ther 2016; 27:687-99. [PMID: 27342665 DOI: 10.1089/hum.2016.053] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The mammalian inner ear consists of diverse cell types with important functions. Gene mutations in these diverse cell types have been found to underlie different forms of genetic hearing loss. Targeting these mutations for gene therapy development represents a future therapeutic strategy to treat hearing loss. Adeno-associated viral (AAV) vectors have become the vector of choice for gene delivery in animal models in vivo. To identify AAV vectors that target inner ear cell subtypes, we systemically screened 12 AAV vectors with different serotypes (AAV1, 2, 5, 6, 6.2, 7, 8, 9, rh.8, rh.10, rh.39, and rh.43) that carry a reporter gene GFP in neonatal and adult mice by microinjection in vivo. We found that most AAVs infect both neonatal and adult inner ear, with different specificities and expression levels. The inner ear cochlear sensory epithelial region, which includes auditory hair cells and supporting cells, is most frequently targeted for gene delivery. Expression of the transgene is sustained, and neonatal inner ear delivery does not adversely affect hearing. Adult inner ear injection of AAV has a similar infection pattern as the younger inner ear, with the exception that outer hair cell death caused by the injection procedure can lead to hearing loss. In the adult, more so than in the neonatal mice, cell types infected and efficiency of infection are correlated with the site of injection. Most infected cells survive in neonatal and adult inner ears. The study adds to the list of AAV vectors that transduce the mammalian inner ear efficiently, providing the tools that are important to study inner ear gene function and for the development of gene therapy to treat hearing loss.
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Affiliation(s)
- Yilai Shu
- 1 Department of Otolaryngology, Harvard Medical School and Eaton-Peabody Laboratories, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts.,2 Department of Otolaryngology-Head and Neck Surgery, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China .,3 Key Laboratory of Hearing Medicine, National Health and Family Planning Commission, Shanghai, China
| | - Yong Tao
- 1 Department of Otolaryngology, Harvard Medical School and Eaton-Peabody Laboratories, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts
| | - Zhengmin Wang
- 2 Department of Otolaryngology-Head and Neck Surgery, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China .,3 Key Laboratory of Hearing Medicine, National Health and Family Planning Commission, Shanghai, China
| | - Yong Tang
- 1 Department of Otolaryngology, Harvard Medical School and Eaton-Peabody Laboratories, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts.,4 Department of Ear, Nose and Throat, People's Hospital of Jilin Province, Changchun, Jilin Province, China
| | - Huawei Li
- 2 Department of Otolaryngology-Head and Neck Surgery, Eye and ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China .,3 Key Laboratory of Hearing Medicine, National Health and Family Planning Commission, Shanghai, China
| | - Pu Dai
- 5 Department of Otolaryngology, Chinese PLA General Hospital, Beijing, People's Republic of China
| | - Guangping Gao
- 6 Horae Gene Therapy Center and Department of Microbiology and Physiological Systems, University of Massachusetts Medical School, Worcester, Massachusetts.,7 State Key Laboratory of Biotherapy, West China Hospital, Sichuan University , Chengdu, Sichuan, China
| | - Zheng-Yi Chen
- 1 Department of Otolaryngology, Harvard Medical School and Eaton-Peabody Laboratories, Massachusetts Eye & Ear Infirmary, Boston, Massachusetts
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24
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Bakondi B, Lv W, Lu B, Jones MK, Tsai Y, Kim KJ, Levy R, Akhtar AA, Breunig JJ, Svendsen CN, Wang S. In Vivo CRISPR/Cas9 Gene Editing Corrects Retinal Dystrophy in the S334ter-3 Rat Model of Autosomal Dominant Retinitis Pigmentosa. Mol Ther 2016; 24:556-63. [PMID: 26666451 PMCID: PMC4786918 DOI: 10.1038/mt.2015.220] [Citation(s) in RCA: 217] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 12/05/2015] [Indexed: 11/09/2022] Open
Abstract
Reliable genome editing via Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)/Cas9 may provide a means to correct inherited diseases in patients. As proof of principle, we show that CRISPR/Cas9 can be used in vivo to selectively ablate the rhodopsin gene carrying the dominant S334ter mutation (Rho(S334)) in rats that model severe autosomal dominant retinitis pigmentosa. A single subretinal injection of guide RNA/Cas9 plasmid in combination with electroporation generated allele-specific disruption of Rho(S334), which prevented retinal degeneration and improved visual function.
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Affiliation(s)
- Benjamin Bakondi
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Wenjian Lv
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
- Current address: Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, Massachusetts, USA
| | - Bin Lu
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Melissa K Jones
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Yuchun Tsai
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Kevin J Kim
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Rachelle Levy
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Aslam Abbasi Akhtar
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Joshua J Breunig
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Clive N Svendsen
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Shaomei Wang
- Board of Governors Regenerative Medicine Institute, Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, California, USA
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25
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Ghazi NG, Abboud EB, Nowilaty SR, Alkuraya H, Alhommadi A, Cai H, Hou R, Deng WT, Boye SL, Almaghamsi A, Al Saikhan F, Al-Dhibi H, Birch D, Chung C, Colak D, LaVail MM, Vollrath D, Erger K, Wang W, Conlon T, Zhang K, Hauswirth W, Alkuraya FS. Treatment of retinitis pigmentosa due to MERTK mutations by ocular subretinal injection of adeno-associated virus gene vector: results of a phase I trial. Hum Genet 2016; 135:327-43. [PMID: 26825853 DOI: 10.1007/s00439-016-1637-y] [Citation(s) in RCA: 157] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 01/15/2016] [Indexed: 12/14/2022]
Abstract
MERTK is an essential component of the signaling network that controls phagocytosis in retinal pigment epithelium (RPE), the loss of which results in photoreceptor degeneration. Previous proof-of-concept studies have demonstrated the efficacy of gene therapy using human MERTK (hMERTK) packaged into adeno-associated virus (AAV2) in treating RCS rats and mice with MERTK deficiency. The purpose of this study was to assess the safety of gene transfer via subretinal administration of rAAV2-VMD2-hMERTK in subjects with MERTK-associated retinitis pigmentosa (RP). After a preclinical phase confirming the safety of the study vector in monkeys, six patients (aged 14 to 54, mean 33.3 years) with MERTK-related RP and baseline visual acuity (VA) ranging from 20/50 to <20/6400 were entered in a phase I open-label, dose-escalation trial. One eye of each patient (the worse-seeing eye in five subjects) received a submacular injection of the viral vector, first at a dose of 150 µl (5.96 × 10(10)vg; 2 patients) and then 450 µl (17.88 × 10(10)vg; 4 patients). Patients were followed daily for 10 days at 30, 60, 90, 180, 270, 365, 540, and 730 days post-injection. Collected data included (1) full ophthalmologic examination including best-corrected VA, intraocular pressure, color fundus photographs, macular spectral domain optical coherence tomography and full-field stimulus threshold test (FST) in both the study and fellow eyes; (2) systemic safety data including CBC, liver and kidney function tests, coagulation profiles, urine analysis, AAV antibody titers, peripheral blood PCR and ASR measurement; and (3) listing of ophthalmological or systemic adverse effects. All patients completed the 2-year follow-up. Subretinal injection of rAAV2-VMD2-hMERTK was associated with acceptable ocular and systemic safety profiles based on 2-year follow-up. None of the patients developed complications that could be attributed to the gene vector with certainty. Postoperatively, one patient developed filamentary keratitis, and two patients developed progressive cataract. Of these two patients, one also developed transient subfoveal fluid after the injection as well as monocular oscillopsia. Two patients developed a rise in AAV antibodies, but neither patient was positive for rAAV vector genomes via PCR. Three patients also displayed measurable improved visual acuity in the treated eye following surgery, although the improvement was lost by 2 years in two of these patients. Gene therapy for MERTK-related RP using careful subretinal injection of rAAV2-VMD2-hMERTK is not associated with major side effects and may result in clinical improvement in a subset of patients.
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Affiliation(s)
- Nicola G Ghazi
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia.,Department of Ophthalmology, University of Virginia, Charlottesville, VA, USA
| | - Emad B Abboud
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Sawsan R Nowilaty
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Hisham Alkuraya
- Department of Ophthalmology, College of Medicine, Al-Imam Muhammad Ibn Saud Islamic University, Riyadh, Saudi Arabia
| | | | - Huimin Cai
- Department of Ophthalmology, Institute for Genomic Medicine, University of California San Diego, San Diego, CA, USA.,Chengdu JiaChuan Biomedicine Co., Ltd, Chengdu, China.,Guangzhou KangRui Biological Pharmaceutical Technology Company Ltd., Guangzhou, China
| | - Rui Hou
- Chengdu JiaChuan Biomedicine Co., Ltd, Chengdu, China.,Guangzhou KangRui Biological Pharmaceutical Technology Company Ltd., Guangzhou, China
| | - Wen-Tao Deng
- Department of Ophthalmology, University of Florida, Gainesville, USA
| | - Sanford L Boye
- Department of Ophthalmology, University of Florida, Gainesville, USA
| | | | - Fahad Al Saikhan
- Department of Medicine, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - Hassan Al-Dhibi
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia
| | - David Birch
- Rose-Silverthorne Retinal Degenerations Laboratory, Retina Foundation of the Southwest, Dallas, USA
| | - Christopher Chung
- Department of Ophthalmology, Institute for Genomic Medicine, University of California San Diego, San Diego, CA, USA
| | - Dilek Colak
- Department of Biostatistics, Epidemiology and Scientific Computing, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Matthew M LaVail
- Beckman Vision Center, University of California San Francisco, San Francisco, CA, USA
| | - Douglas Vollrath
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Kirsten Erger
- Department of Pediatrics, Powell Gene Therapy Center, University of Florida, Gainesville, USA
| | - Wenqiu Wang
- Chengdu JiaChuan Biomedicine Co., Ltd, Chengdu, China.,Guangzhou KangRui Biological Pharmaceutical Technology Company Ltd., Guangzhou, China
| | - Thomas Conlon
- Department of Pediatrics, Powell Gene Therapy Center, University of Florida, Gainesville, USA
| | - Kang Zhang
- Department of Ophthalmology, Institute for Genomic Medicine, University of California San Diego, San Diego, CA, USA.,Veterans Administration Healthcare System, San Diego, CA, 92093, USA
| | - William Hauswirth
- Department of Ophthalmology, University of Florida, Gainesville, USA
| | - Fowzan S Alkuraya
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia. .,Department of Anatomy and Cell Biology, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia.
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26
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Scott PA, Kaplan HJ, McCall MA. Prenatal Exposure to Curcumin Protects Rod Photoreceptors in a Transgenic Pro23His Swine Model of Retinitis Pigmentosa. Transl Vis Sci Technol 2015; 4:5. [PMID: 26396931 DOI: 10.1167/tvst.4.5.5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Accepted: 08/12/2015] [Indexed: 01/06/2023] Open
Abstract
PURPOSE Rhodopsin localization and rod photoreceptor (PR) morphology is altered in embryonic transgenic (Tg) Pro23His (P23H) miniswine. At birth, the Tg P23H swine retina lacks rod driven signaling. Curcumin, a neuroprotective food additive, has been shown to rescue Tg P23H rat rod PRs and promote normal trafficking of rhodopsin. We tested the hypothesis that prenatal exposure to curcumin would prevent PR morphological changes in Tg P23H miniswine retinae. METHODS A domestic sow was inseminated with semen from a Tg P23H miniswine founder. Her daily diet was supplemented with curcumin (100 mg/Kg body weight) from embryonic (E) day 80 to E112. The same diet without curcumin was fed to a second inseminated control sow. At E112, 2 days before parturition, both sows were euthanized. Their embryos were harvested, genotyped, and their eyes enucleated and prepared for morphological evaluation. RESULTS In all pigs, we measured mean outer retinal thickness, localization of rhodopsin, and rod PR morphology. Curcumin-treated Tg P23H swine embryonic retinas were similar to WT. Untreated Tg P23H embryonic retinas show significant degenerative effects; their outer retina was thinner, rod PR morphology was abnormal, and rhodopsin was mislocalized to the outer nuclear layer (ONL). CONCLUSIONS These data support a role for curcumin as a neuroprotective agent that prevents/delays morphological abnormalities associated with rod PR degeneration in this Tg P23H swine model of retinitis pigmentosa (RP). TRANSLATIONAL RELEVANCE Curcumin, a Food and Drug Administration-approved dietary supplement, may arrest/delay PR degeneration if ingested by individuals at risk for developing RP.
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Affiliation(s)
- Patrick A Scott
- Departments of Ophthalmology & Visual Sciences, University of Louisville, Louisville, KY, USA ; Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY, USA
| | - Henry J Kaplan
- Departments of Ophthalmology & Visual Sciences, University of Louisville, Louisville, KY, USA ; Microbiology and Immunology, University of Louisville, Louisville, KY, USA
| | - Maureen A McCall
- Departments of Ophthalmology & Visual Sciences, University of Louisville, Louisville, KY, USA ; Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY, USA
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27
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Koch SF, Tsai YT, Duong JK, Wu WH, Hsu CW, Wu WP, Bonet-Ponce L, Lin CS, Tsang SH. Halting progressive neurodegeneration in advanced retinitis pigmentosa. J Clin Invest 2015; 125:3704-13. [PMID: 26301813 DOI: 10.1172/jci82462] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 07/13/2015] [Indexed: 01/03/2023] Open
Abstract
Hereditary retinal degenerative diseases, such as retinitis pigmentosa (RP), are characterized by the progressive loss of rod photoreceptors followed by loss of cones. While retinal gene therapy clinical trials demonstrated temporary improvement in visual function, this approach has yet to achieve sustained functional and anatomical rescue after disease onset in patients. The lack of sustained benefit could be due to insufficient transduction efficiency of viral vectors ("too little") and/or because the disease is too advanced ("too late") at the time therapy is initiated. Here, we tested the latter hypothesis and developed a mouse RP model that permits restoration of the mutant gene in all diseased photoreceptor cells, thereby ensuring sufficient transduction efficiency. We then treated mice at early, mid, or late disease stages. At all 3 time points, degeneration was halted and function was rescued for at least 1 year. Not only do our results demonstrate that gene therapy effectively preserves function after the onset of degeneration, our study also demonstrates that there is a broad therapeutic time window. Moreover, these results suggest that RP patients are treatable, despite most being diagnosed after substantial photoreceptor loss, and that gene therapy research must focus on improving transduction efficiency to maximize clinical impact.
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28
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Dong X, Ramon E, Herrera-Hernández MG, Garriga P. Phospholipid Bicelles Improve the Conformational Stability of Rhodopsin Mutants Associated with Retinitis Pigmentosa. Biochemistry 2015; 54:4795-804. [PMID: 26181234 DOI: 10.1021/acs.biochem.5b00435] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Mutations in the visual photoreceptor rhodopsin are the cause of the retinal degenerative disease retinitis pigmentosa. Some naturally occurring mutations can lead to protein conformational instability. Two such mutations, N55K and G90V, in the first and second transmembrane helices of the receptor, have been associated with sector and classical retinitis pigmentosa, respectively, and showed enhanced thermal sensitivity. We have carefully analyzed the effect of phospholipid bicelles on the stability and ligand binding properties of these two mutants and compared it with those of the detergent-solubilized samples. We have used a phospholipid bilayer consisting of 1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine (DMPC) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC). We find that DMPC/DHPC bicelles dramatically increase the thermal stability of the rhodopsin mutants G90V and N55K. The chromophore stability and regeneration of the mutants were also increased in bicelles when compared to their behavior in a dodecyl maltoside detergent solution. The retinal release process was slowed in bicelles, and chromophore entry, after illumination, was improved for the G90V mutant but not for N55K. Furthermore, fluorescence spectroscopy measurements showed that bicelles allowed more exogenous retinal binding to the photoactivated G90V mutant than in a detergent solution. In contrast, N55K could not reposition any chromophore either in the detergent or in bicelles. The results demonstrate that DMPC/DHPC bicelles can counteract the destabilizing effect of the disease-causing mutations and can modulate the structural changes in the ensuing receptor photoactivation in a distinct specific manner for different retinitis pigmentosa mutant phenotypes.
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Affiliation(s)
- Xiaoyun Dong
- Grup de Biotecnologia Molecular i Industrial, Centre de Biotecnologia Molecular, Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Edifici Gaia, Rambla de Sant Nebridi 22, 08222 Terrassa, Catalonia, Spain
| | - Eva Ramon
- Grup de Biotecnologia Molecular i Industrial, Centre de Biotecnologia Molecular, Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Edifici Gaia, Rambla de Sant Nebridi 22, 08222 Terrassa, Catalonia, Spain
| | - María Guadalupe Herrera-Hernández
- Grup de Biotecnologia Molecular i Industrial, Centre de Biotecnologia Molecular, Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Edifici Gaia, Rambla de Sant Nebridi 22, 08222 Terrassa, Catalonia, Spain
| | - Pere Garriga
- Grup de Biotecnologia Molecular i Industrial, Centre de Biotecnologia Molecular, Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Edifici Gaia, Rambla de Sant Nebridi 22, 08222 Terrassa, Catalonia, Spain
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29
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Ho AC, Humayun MS, Dorn JD, da Cruz L, Dagnelie G, Handa J, Barale PO, Sahel JA, Stanga PE, Hafezi F, Safran AB, Salzmann J, Santos A, Birch D, Spencer R, Cideciyan AV, de Juan E, Duncan JL, Eliott D, Fawzi A, Olmos de Koo LC, Brown GC, Haller JA, Regillo CD, Del Priore LV, Arditi A, Geruschat DR, Greenberg RJ. Long-Term Results from an Epiretinal Prosthesis to Restore Sight to the Blind. Ophthalmology 2015; 122:1547-54. [PMID: 26162233 DOI: 10.1016/j.ophtha.2015.04.032] [Citation(s) in RCA: 192] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Revised: 04/21/2015] [Accepted: 04/21/2015] [Indexed: 11/25/2022] Open
Abstract
PURPOSE Retinitis pigmentosa (RP) is a group of inherited retinal degenerations leading to blindness due to photoreceptor loss. Retinitis pigmentosa is a rare disease, affecting only approximately 100 000 people in the United States. There is no cure and no approved medical therapy to slow or reverse RP. The purpose of this clinical trial was to evaluate the safety, reliability, and benefit of the Argus II Retinal Prosthesis System (Second Sight Medical Products, Inc, Sylmar, CA) in restoring some visual function to subjects completely blind from RP. We report clinical trial results at 1 and 3 years after implantation. DESIGN The study is a multicenter, single-arm, prospective clinical trial. PARTICIPANTS There were 30 subjects in 10 centers in the United States and Europe. Subjects served as their own controls, that is, implanted eye versus fellow eye, and system on versus system off (native residual vision). METHODS The Argus II System was implanted on and in a single eye (typically the worse-seeing eye) of blind subjects. Subjects wore glasses mounted with a small camera and a video processor that converted images into stimulation patterns sent to the electrode array on the retina. MAIN OUTCOME MEASURES The primary outcome measures were safety (the number, seriousness, and relatedness of adverse events) and visual function, as measured by 3 computer-based, objective tests. RESULTS A total of 29 of 30 subjects had functioning Argus II Systems implants 3 years after implantation. Eleven subjects experienced a total of 23 serious device- or surgery-related adverse events. All were treated with standard ophthalmic care. As a group, subjects performed significantly better with the system on than off on all visual function tests and functional vision assessments. CONCLUSIONS The 3-year results of the Argus II trial support the long-term safety profile and benefit of the Argus II System for patients blind from RP. Earlier results from this trial were used to gain approval of the Argus II by the Food and Drug Administration and a CE mark in Europe. The Argus II System is the first and only retinal implant to have both approvals.
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Affiliation(s)
- Allen C Ho
- Wills Eye Hospital, Philadelphia, Pennsylvania.
| | - Mark S Humayun
- University of Southern California, Los Angeles, California
| | - Jessy D Dorn
- Second Sight Medical Products, Sylmar, California
| | - Lyndon da Cruz
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom; NHIR Moorfields Biomedical Research Centre, London, United Kingdom
| | - Gislin Dagnelie
- Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland
| | - James Handa
- Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland
| | | | - José-Alain Sahel
- Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France; ELZA Institute, Zurich, Switzerland
| | - Paulo E Stanga
- Manchester Royal Eye Hospital, Manchester, United Kingdom; Manchester Vision Regeneration Lab at National Institute for Health Research/Wellcome Trust Manchester CRF, Manchester, United Kingdom; Manchester Academic Health Science Centre and Centre for Ophthalmology and Vision Research, Institute of Human Development, University of Manchester, Manchester, United Kingdom
| | - Farhad Hafezi
- University of Southern California, Los Angeles, California; Hôpitaux Universitaires de Genève, Geneva, Switzerland; ELZA Institute, Zurich, Switzerland
| | - Avinoam B Safran
- Hôpitaux Universitaires de Genève, Geneva, Switzerland; Sorbonne Universities - UPMC Paris-6, and Institut de la Vision, Paris, France
| | - Joel Salzmann
- Hôpitaux Universitaires de Genève, Geneva, Switzerland
| | - Arturo Santos
- Centro de Retina Medica y Quirúrgica, SC, Guadalajara, Mexico; Tecnologico de Monterrey, Guadalajara, Mexico
| | - David Birch
- Retina Foundation of the Southwest, Dallas, Texas
| | | | - Artur V Cideciyan
- Scheie Eye Institute, University of Pennsylvania, Philadelphia, Pennsylvania
| | - Eugene de Juan
- University of California, San Francisco, San Francisco, California
| | - Jacque L Duncan
- University of California, San Francisco, San Francisco, California
| | - Dean Eliott
- University of Southern California, Los Angeles, California; Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts
| | - Amani Fawzi
- University of Southern California, Los Angeles, California; Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | | | | | - Julia A Haller
- Wills Eye Hospital, Philadelphia, Pennsylvania; Wilmer Eye Institute, Johns Hopkins University, Baltimore, Maryland
| | | | - Lucian V Del Priore
- Columbia University, New York, New York; Storm Eye Institute, Charleston, South Carolina
| | - Aries Arditi
- Lighthouse Guild, New York, New York; Visibility Metrics, LLC, Chappaqua, New York
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30
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Gurevich EV, Gurevich VV. Beyond traditional pharmacology: new tools and approaches. Br J Pharmacol 2015; 172:3229-41. [PMID: 25572005 DOI: 10.1111/bph.13066] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 11/24/2014] [Accepted: 01/02/2015] [Indexed: 12/14/2022] Open
Abstract
Traditional pharmacology is defined as the science that deals with drugs and their actions. While small molecule drugs have clear advantages, there are many cases where they have proved to be ineffective, prone to unacceptable side effects, or where due to a particular disease aetiology they cannot possibly be effective. A dominant feature of the small molecule drugs is their single mindedness: they provide either continuous inhibition or continuous activation of the target. Because of that, these drugs tend to engage compensatory mechanisms leading to drug tolerance, drug resistance or, in some cases, sensitization and consequent loss of therapeutic efficacy over time and/or unwanted side effects. Here we discuss new and emerging therapeutic tools and approaches that have potential for treating the majority of disorders for which small molecules are either failing or cannot be developed. These new tools include biologics, such as recombinant hormones and antibodies, as well as approaches involving gene transfer (gene therapy and genome editing) and the introduction of specially designed self-replicating cells. It is clear that no single method is going to be a 'silver bullet', but collectively, these novel approaches hold promise for curing practically every disorder.
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Affiliation(s)
- E V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
| | - V V Gurevich
- Department of Pharmacology, Vanderbilt University, Nashville, TN, USA
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31
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Yvon C, Ramsden CM, Lane A, Powner MB, da Cruz L, Coffey PJ, Carr AJF. Using Stem Cells to Model Diseases of the Outer Retina. Comput Struct Biotechnol J 2015; 13:382-9. [PMID: 26106463 PMCID: PMC4477013 DOI: 10.1016/j.csbj.2015.05.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 04/30/2015] [Accepted: 05/01/2015] [Indexed: 12/13/2022] Open
Abstract
Retinal degeneration arises from the loss of photoreceptors or retinal pigment epithelium (RPE). It is one of the leading causes of irreversible blindness worldwide with limited effective treatment options. Generation of induced pluripotent stem cell (IPSC)-derived retinal cells and tissues from individuals with retinal degeneration is a rapidly evolving technology that holds a great potential for its use in disease modelling. IPSCs provide an ideal platform to investigate normal and pathological retinogenesis, but also deliver a valuable source of retinal cell types for drug screening and cell therapy. In this review, we will provide some examples of the ways in which IPSCs have been used to model diseases of the outer retina including retinitis pigmentosa (RP), Usher syndrome (USH), Leber congenital amaurosis (LCA), gyrate atrophy (GA), juvenile neuronal ceroid lipofuscinosis (NCL), Best vitelliform macular dystrophy (BVMD) and age related macular degeneration (AMD).
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Affiliation(s)
- Camille Yvon
- The London Project to Cure Blindness, Division of ORBIT, Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
| | - Conor M. Ramsden
- The London Project to Cure Blindness, Division of ORBIT, Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
- NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust, UCL Institute of Ophthalmology, London, EC1V 2PD, UK
| | - Amelia Lane
- The London Project to Cure Blindness, Division of ORBIT, Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
| | - Michael B. Powner
- The London Project to Cure Blindness, Division of ORBIT, Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
| | - Lyndon da Cruz
- The London Project to Cure Blindness, Division of ORBIT, Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
- NIHR Biomedical Research Centre at Moorfields Eye Hospital NHS Foundation Trust, UCL Institute of Ophthalmology, London, EC1V 2PD, UK
| | - Peter J. Coffey
- The London Project to Cure Blindness, Division of ORBIT, Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
- Center for Stem Cell Biology and Engineering, NRI, UC, Santa Barbara, USA
| | - Amanda-Jayne F. Carr
- The London Project to Cure Blindness, Division of ORBIT, Institute of Ophthalmology, University College London, 11-43 Bath Street, London EC1V 9EL, UK
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32
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Abstract
Hearing loss is the most common form of sensory impairment in humans and affects more than 40 million people in the United States alone. No drug-based therapy has been approved by the Food and Drug Administration, and treatment mostly relies on devices such as hearing aids and cochlear implants. Over recent years, more than 100 genetic loci have been linked to hearing loss and many of the affected genes have been identified. This understanding of the genetic pathways that regulate auditory function has revealed new targets for pharmacological treatment of the disease. Moreover, approaches that are based on stem cells and gene therapy, which may have the potential to restore or maintain auditory function, are beginning to emerge.
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Affiliation(s)
- Ulrich Müller
- Department of Molecular and Cellular Neuroscience, Dorris Neuroscience Center, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, San Diego, California 92037, USA
| | - Peter G Barr-Gillespie
- Oregon Hearing Research Center, Vollum Institute, Oregon Health &Science University, 3181 South West Sam Jackson Park Road, Portland, Oregon 97239, USA
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33
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Chen Y, Tang H. High-throughput screening assays to identify small molecules preventing photoreceptor degeneration caused by the rhodopsin P23H mutation. Methods Mol Biol 2015; 1271:369-90. [PMID: 25697536 DOI: 10.1007/978-1-4939-2330-4_24] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
High-throughput screening (HTS) is one of the major techniques for discovering promising molecules for drug development. Rhodopsin mutations cause the most common autosomal dominant form of retinitis pigmentosa, an inherited retinal degenerative disease that currently has no effective treatment. To find an optimal pharmacological treatment for rhodopsin-associated retinitis pigmentosa, we performed two cell-based HTSs with mammalian cells expressing the P23H rod opsin mutant and identified two sets of novel compounds for further validation and characterization. The first HTS screen identified pharmacological chaperones of P23H opsin that increased its translocation from the endoplasmic reticulum to the plasma membrane. The second HTS screen selected small molecules that enhanced the clearance of the mutant opsin while vision could be sustained by the healthy gene allele expressing wild-type rhodopsin. Here we describe the methodology of these two HTS assays in detail.
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Affiliation(s)
- Yuanyuan Chen
- Department of Pharmacology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH, 44106-4965, USA,
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Ramon E, Cordomí A, Aguilà M, Srinivasan S, Dong X, Moore AT, Webster AR, Cheetham ME, Garriga P. Differential light-induced responses in sectorial inherited retinal degeneration. J Biol Chem 2014; 289:35918-28. [PMID: 25359768 DOI: 10.1074/jbc.m114.609958] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Retinitis pigmentosa (RP) is a group of genetically and clinically heterogeneous inherited degenerative retinopathies caused by abnormalities of photoreceptors or retinal pigment epithelium in the retina leading to progressive sight loss. Rhodopsin is the prototypical G-protein-coupled receptor located in the vertebrate retina and is responsible for dim light vision. Here, novel M39R and N55K variants were identified as causing an intriguing sector phenotype of RP in affected patients, with selective degeneration in the inferior retina. To gain insights into the molecular aspects associated with this sector RP phenotype, whose molecular mechanism remains elusive, the mutations were constructed by site-directed mutagenesis, expressed in heterologous systems, and studied by biochemical, spectroscopic, and functional assays. M39R and N55K opsins had variable degrees of chromophore regeneration when compared with WT opsin but showed no gross structural misfolding or altered trafficking. M39R showed a faster rate for transducin activation than WT rhodopsin with a faster metarhodopsinII decay, whereas N55K presented a reduced activation rate and an altered photobleaching pattern. N55K also showed an altered retinal release from the opsin binding pocket upon light exposure, affecting its optimal functional response. Our data suggest that these sector RP mutations cause different protein phenotypes that may be related to their different clinical progression. Overall, these findings illuminate the molecular mechanisms of sector RP associated with rhodopsin mutations.
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Affiliation(s)
- Eva Ramon
- From the Centre de Biotecnologia Molecular, Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Rambla de Sant Nebridi 22, 08222 Terrassa, Spain
| | - Arnau Cordomí
- the Laboratori de Medicina Computacional, Unitat de Bioestadística, Facultat de Medicina, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Spain
| | - Mònica Aguilà
- the University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, United Kingdom, and
| | - Sundaramoorthy Srinivasan
- From the Centre de Biotecnologia Molecular, Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Rambla de Sant Nebridi 22, 08222 Terrassa, Spain
| | - Xiaoyun Dong
- From the Centre de Biotecnologia Molecular, Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Rambla de Sant Nebridi 22, 08222 Terrassa, Spain
| | - Anthony T Moore
- the University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, United Kingdom, and the Moorfields Eye Hospital, London EC1V 2PD, United Kingdom
| | - Andrew R Webster
- the University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, United Kingdom, and the Moorfields Eye Hospital, London EC1V 2PD, United Kingdom
| | - Michael E Cheetham
- the University College London Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, United Kingdom, and
| | - Pere Garriga
- From the Centre de Biotecnologia Molecular, Departament d'Enginyeria Química, Universitat Politècnica de Catalunya, Rambla de Sant Nebridi 22, 08222 Terrassa, Spain,
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Abstract
Gene therapy has been considered as the most ideal medical intervention for genetic diseases because it is intended to target the cause of diseases instead of disease symptoms. Availability of techniques for identification of genetic mutations and for in vitro manipulation of genes makes it practical and attractive. After the initial hype in 1990s and later disappointments in clinical trials for more than a decade, light has finally come into the tunnel in recent years, especially in the field of eye gene therapy where it has taken big strides. Clinical trials in gene therapy for retinal degenerative diseases such as Leber's congenital amaurosis (LCA) and choroideremia demonstrated clear therapeutic efficacies without apparent side effects. Although these successful examples are still rare and sporadic in the field, they provide the proof of concept for harnessing the power of gene therapy to treat genetic diseases and to modernize our medication. In addition, those success stories illuminate the path for the development of gene therapy treating other genetic diseases. Because of the differences in target organs and cells, distinct barriers to gene delivery exist in gene therapy for each genetic disease. It is not feasible for authors to review the current development in the entire field. Thus, in this article, we will focus on what we can learn from the current success in gene therapy for retinal degenerative diseases to speed up the gene therapy development for lung diseases, such as cystic fibrosis.
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Recent advances of stem cell therapy for retinitis pigmentosa. Int J Mol Sci 2014; 15:14456-74. [PMID: 25141102 PMCID: PMC4159862 DOI: 10.3390/ijms150814456] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2014] [Revised: 07/24/2014] [Accepted: 08/11/2014] [Indexed: 12/22/2022] Open
Abstract
Retinitis pigmentosa (RP) is a group of inherited retinal disorders characterized by progressive loss of photoreceptors and eventually leads to retina degeneration and atrophy. Until now, the exact pathogenesis and etiology of this disease has not been clear, and many approaches for RP therapies have been carried out in animals and in clinical trials. In recent years, stem cell transplantation-based attempts made some progress, especially the transplantation of bone marrow-derived mesenchymal stem cells (BMSCs). This review will provide an overview of stem cell-based treatment of RP and its main problems, to provide evidence for the safety and feasibility for further clinical treatment.
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Carvalho LS, Vandenberghe LH. Promising and delivering gene therapies for vision loss. Vision Res 2014; 111:124-33. [PMID: 25094052 DOI: 10.1016/j.visres.2014.07.013] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 07/25/2014] [Accepted: 07/28/2014] [Indexed: 12/14/2022]
Abstract
The maturity in our understanding of the genetics and the pathogenesis of disease in degenerative retinal disorders has intersected in past years with a novel treatment paradigm in which a genetic intervention may lead to sustained therapeutic benefit, and in some cases even restoration of vision. Here, we review this prospect of retinal gene therapy, discuss the enabling technologies that have led to first-in-human demonstrations of efficacy and safety, and the road that led to this exciting point in time.
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Affiliation(s)
- Livia S Carvalho
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Harvard University, 20 Staniford Street, Boston, MA 02114, USA
| | - Luk H Vandenberghe
- Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Department of Ophthalmology, Harvard Medical School, Harvard University, 20 Staniford Street, Boston, MA 02114, USA.
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