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Yan B, Viswanathan S, Brodie SE, Deng WT, Coleman KE, Hauswirth WW, Nirenberg S. A clinically viable approach to restoring visual function using optogenetic gene therapy. Mol Ther Methods Clin Dev 2023; 29:406-417. [PMID: 37251979 PMCID: PMC10213293 DOI: 10.1016/j.omtm.2023.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Accepted: 05/04/2023] [Indexed: 05/31/2023]
Abstract
Optogenetic gene therapies offer a promising strategy for restoring vision to patients with retinal degenerative diseases, such as retinitis pigmentosa (RP). Several clinical trials have begun in this area using different vectors and optogenetic proteins (Clinical Identifiers: NCT02556736, NCT03326336, NCT04945772, and NCT04278131). Here we present preclinical efficacy and safety data for the NCT04278131 trial, which uses an AAV2 vector and Chronos as the optogenetic protein. Efficacy was assessed in mice in a dose-dependent manner using electroretinograms (ERGs). Safety was assessed in rats, nonhuman primates, and mice, using several tests, including immunohistochemical analyses and cell counts (rats), electroretinograms (nonhuman primates), and ocular toxicology assays (mice). The results showed that Chronos-expressing vectors were efficacious over a broad range of vector doses and stimulating light intensities, and were well tolerated: no test article-related findings were observed in the anatomical and electrophysiological assays performed.
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Affiliation(s)
- Boyuan Yan
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10065, USA
- Bionic Sight, Inc., New York, NY 10065, USA
| | - Suresh Viswanathan
- Department of Biological and Vision Sciences, College of Optometry, State University of New York, New York, NY 10036, USA
| | - Scott E. Brodie
- Department of Ophthalmology, NYU Langone Health, New York, NY 10017, USA
| | - Wen-Tao Deng
- Department of Ophthalmology and Visual Sciences, School of Medicine, West Virginia University, Morgantown, WV 26506, USA
| | - Kirsten E. Coleman
- Powel Gene Therapy Center Toxicology Core, University of Florida, Gainesville, FL 32610, USA
| | - William W. Hauswirth
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL 32603, USA
- Bionic Sight, Inc., New York, NY 10065, USA
| | - Sheila Nirenberg
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY 10065, USA
- Bionic Sight, Inc., New York, NY 10065, USA
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2
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Tao Y, Hu B, Ma Z, Li H, Du E, Wang G, Xing B, Ma J, Song Z. Intravitreous delivery of melatonin affects the retinal neuron survival and visual signal transmission: in vivo and ex vivo study. Drug Deliv 2021; 27:1386-1396. [PMID: 33016801 PMCID: PMC7580852 DOI: 10.1080/10717544.2020.1818882] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Intravitreal delivery can maximize the intensity of therapeutic agents and extend their residence time within ocular tissue. Melatonin is a lipophilic molecule that crosses freely biological barriers and cell membranes. This study intends to investigate the effects of intravitreally delivered melatonin on mouse retina. The visual function of administered mice is assessed by electrophysiological and behavior examinations three weeks after intravitreal delivery. Moreover, multi-electrode array (MEA) was used to assess the electrical activities of retinal ganglion cells (RGCs). We found that intravitreal delivery of high dosage melatonin (400-500 µg/kg) destroyed the retinal architecture and impaired the visual function of mice. Conversely, the melatonin administration at low dose (100-300 µg/kg) did not have any significant effects on the photoreceptor survival or visual function. As shown in the MEA recording, the photoreceptors activity of the central region was more severely disturbed by the high dose melatonin. A pronounced augment of the spontaneous firing frequency was recorded in these mice received high dosage melatonin, indicating that intravitreal delivery of high dosage melatonin would affect the electrical activity of RGCs. Immunostaining assay showed that the vitality of cone photoreceptor was impaired by high dose melatonin. These findings suggest that intravitreal melatonin is not always beneficial for ocular tissues, especially when it is administered at high dosage. These data add new perspectives to current knowledge about melatonin delivery at the ocular level. Further therapeutic strategies should take into consideration of these risks that caused by delivery approach.
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Affiliation(s)
- Ye Tao
- Department of Ophthalmology, People's hospital of Zhengzhou University, Zhengzhou, PR China.,Department of physiology and neuroscience, Basic college of medicine, Zhengzhou University Zhengzhou, PR China
| | - Bang Hu
- Department of Colorectal Surgery, The Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, PR China
| | - Zhao Ma
- Department of Neurosurgery, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wu Han, PR China
| | - Haijun Li
- Department of Ophthalmology, People's hospital of Zhengzhou University, Zhengzhou, PR China.,Department of physiology and neuroscience, Basic college of medicine, Zhengzhou University Zhengzhou, PR China
| | - Enming Du
- Department of Ophthalmology, People's hospital of Zhengzhou University, Zhengzhou, PR China.,Department of physiology and neuroscience, Basic college of medicine, Zhengzhou University Zhengzhou, PR China
| | - Gang Wang
- Department of Ophthalmology, People's hospital of Zhengzhou University, Zhengzhou, PR China.,Department of physiology and neuroscience, Basic college of medicine, Zhengzhou University Zhengzhou, PR China
| | - Biao Xing
- Department of Neurosurgery, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wu Han, PR China
| | - Jie Ma
- Department of Neurosurgery, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wu Han, PR China
| | - Zongming Song
- Department of Ophthalmology, People's hospital of Zhengzhou University, Zhengzhou, PR China.,Department of physiology and neuroscience, Basic college of medicine, Zhengzhou University Zhengzhou, PR China
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3
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Ji L, Li L, Zhao Y, Liu S, Li J, Zhang J, Zhao Q, Wang S. Immunosubunit β5i Knockout Suppresses Neovascularization and Restores Autophagy in Retinal Neovascularization by Targeting ATG5 for Degradation. Invest Ophthalmol Vis Sci 2021; 61:30. [PMID: 33369639 PMCID: PMC7774061 DOI: 10.1167/iovs.61.14.30] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To investigate the functional role of immunoproteasome subunit β5i in pathologic retinal neovascularization (RNV) and its ability to link the immunoproteasome and autophagy. Methods Oxygen-induced retinopathy (OIR) was induced in wild-type (WT) and β5i knockout (KO) mouse pups on a C57BL/6J background. Proteasome catalytic subunit expression and proteasome activity were evaluated by quantitative real-time PCR (qPCR) and proteasome activity. Retinal vascular anatomy and neovascularization were characterized and quantified by retinal vascular flat-mount staining, fluorescence angiography, platelet endothelial cell adhesion molecule (PECAM) immunostaining, and hematoxylin and eosin staining. Correlation factors, including VEGF and ICAM-1, were detected by qPCR. Autophagy was examined by transmission electron microscopy (TEM). Autophagy biomarkers, including LC3, P62, ATG5, and ATG7, were measured by immunostaining and immunoblotting. The protein interaction between β5i and ATG5 was detected by immunoprecipitation. Results We observed that β5i had the greatest effect in WT OIR mice. Fundus fluorescence angiography, retinal flat-mount staining, and PECAM staining revealed that pathologic RNV decreased in β5i KO OIR mice compared with WT OIR mice. Concurrently, TEM, immunostaining, and immunoblotting showed that autophagy was induced in β5i KO OIR mice compared to WT OIR mice through increases in autophagosome and LC3 expression and a decrease in P62. Mechanistically, β5i interacted with ATG5 and promoted its degradation, leading to autophagy inhibition and pathogenic RNV. Conclusions This study identifies a functional role for β5i in RNV regulation. β5i deletion ameliorates RNV and restores autophagy by stabilizing ATG5. These results demonstrate the potential of β5i to serve as a bridge linking the immunoproteasome and autophagy.
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Affiliation(s)
- Liyang Ji
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China
| | - Li Li
- Department of Ophthalmology, Zaozhuang Municipal Hospital, Zaozhuang, Shandong, China
| | - Ying Zhao
- Department of Ophthalmology, Jianping County Hospital, Chaoyang, China
| | - Shengqiang Liu
- Department of Ophthalmology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Jingmin Li
- Department of Ophthalmology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Jinsong Zhang
- Department of Ophthalmology, The Fourth Affiliated Hospital of China Medical University, Shenyang, China.,Aier Excellence Eye Hospital, Shenyang, China
| | - Qi Zhao
- Department of Ophthalmology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
| | - Shuai Wang
- Department of Ophthalmology, The Second Affiliated Hospital of Dalian Medical University, Dalian, China
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4
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Li H, Yang Y, Hong W, Huang M, Wu M, Zhao X. Applications of genome editing technology in the targeted therapy of human diseases: mechanisms, advances and prospects. Signal Transduct Target Ther 2020; 5:1. [PMID: 32296011 PMCID: PMC6946647 DOI: 10.1038/s41392-019-0089-y] [Citation(s) in RCA: 857] [Impact Index Per Article: 214.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 09/21/2019] [Accepted: 09/21/2019] [Indexed: 02/06/2023] Open
Abstract
Based on engineered or bacterial nucleases, the development of genome editing technologies has opened up the possibility of directly targeting and modifying genomic sequences in almost all eukaryotic cells. Genome editing has extended our ability to elucidate the contribution of genetics to disease by promoting the creation of more accurate cellular and animal models of pathological processes and has begun to show extraordinary potential in a variety of fields, ranging from basic research to applied biotechnology and biomedical research. Recent progress in developing programmable nucleases, such as zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs) and clustered regularly interspaced short palindromic repeat (CRISPR)-Cas-associated nucleases, has greatly expedited the progress of gene editing from concept to clinical practice. Here, we review recent advances of the three major genome editing technologies (ZFNs, TALENs, and CRISPR/Cas9) and discuss the applications of their derivative reagents as gene editing tools in various human diseases and potential future therapies, focusing on eukaryotic cells and animal models. Finally, we provide an overview of the clinical trials applying genome editing platforms for disease treatment and some of the challenges in the implementation of this technology.
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Affiliation(s)
- Hongyi Li
- Department of Gynecology and Obstetrics, Development and Related Disease of Women and Children Key Laboratory of Sichuan Province, Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, West China Second Hospital, Sichuan University, Chengdu, 610041, P. R. China
| | - Yang Yang
- Department of Gynecology and Obstetrics, Development and Related Disease of Women and Children Key Laboratory of Sichuan Province, Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, West China Second Hospital, Sichuan University, Chengdu, 610041, P. R. China
| | - Weiqi Hong
- Laboratory of Aging Research and Cancer Drug Target, State Key Laboratory of Biotherapy, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, No. 17, Block 3, Southern Renmin Road, Chengdu, Sichuan, 610041, P. R. China
| | - Mengyuan Huang
- Laboratory of Aging Research and Cancer Drug Target, State Key Laboratory of Biotherapy, National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, No. 17, Block 3, Southern Renmin Road, Chengdu, Sichuan, 610041, P. R. China
| | - Min Wu
- Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND, 58203, USA.
| | - Xia Zhao
- Department of Gynecology and Obstetrics, Development and Related Disease of Women and Children Key Laboratory of Sichuan Province, Key Laboratory of Birth Defects and Related Diseases of Women and Children, Ministry of Education, West China Second Hospital, Sichuan University, Chengdu, 610041, P. R. China.
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5
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Wang S, Li J, Wang T, Bai J, Zhang YL, Lin QY, Li JM, Zhao Q, Guo SB, Li HH. Ablation of Immunoproteasome β5i Subunit Suppresses Hypertensive Retinopathy by Blocking ATRAP Degradation in Mice. Mol Ther 2019; 28:279-292. [PMID: 31636038 DOI: 10.1016/j.ymthe.2019.09.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2018] [Revised: 09/11/2019] [Accepted: 09/26/2019] [Indexed: 02/07/2023] Open
Abstract
Inflammation is associated with retinal diseases. Our recent data demonstrate that immunoproteasome catalytic subunit β2i contributes to angiotensin II (Ang II)-induced retinopathy in mice. Here, we investigated the role of another catalytic subunit β5i in regulating retinopathy and its underlying mechanisms. We induced a murine model of retinopathy by infusing Ang II (3,000 ng/kg/min) for 3 weeks into wild-type (WT) mice, β5i-knockout (KO) mice, or WT mice injected with either adenovirus-expressing β5i (Ad-β5i) or angiotensin II type 1 receptor (AT1R)-associated protein (Ad-ATRAP), which inhibits AT1R. The β5i expression and chymotrypsin-like activity were most significantly elevated in Ang II-infused retinas and serum from patients with hypertensive retinopathy. Moreover, Ang II infusion-induced retinopathy was markedly attenuated in β5i-KO mice but aggravated in Ad-β5i-injected mice. Accordingly, β5i KO markedly restored Ang II-induced downregulation of ATRAP and activation of AT1R downstream mediators, which was further enhanced in Ad-β5i-injected mice. Interestingly, overexpression of ATRAP significantly abrogated Ang II-induced retinopathy in Ad-β5i-injected mice. This study found that β5i promoted Ang II-induced retinopathy by promoting ATRAP degradation and activation of AT1R-mediated signals.
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Affiliation(s)
- Shuai Wang
- Department of Ophthalmology, Institute of Heart and Vascular Diseases, Second Affiliated Hospital of Dalian Medical University, Dalian 116027, Liaoning, China.
| | - Jing Li
- Department of Cardiology, Institute of Heart and Vascular Diseases, Second Affiliated Hospital of Dalian Medical University, Dalian 116027, Liaoning, China
| | - Tong Wang
- Department of Ophthalmology, Institute of Heart and Vascular Diseases, Second Affiliated Hospital of Dalian Medical University, Dalian 116027, Liaoning, China
| | - Jie Bai
- Department of Cardiology, Institute of Cardiovascular Diseases, First Affiliated Hospital of Dalian Medical University, Dalian 116011, Liaoning, China
| | - Yun-Long Zhang
- Department of Emergency Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China
| | - Qiu-Yue Lin
- Department of Cardiology, Institute of Cardiovascular Diseases, First Affiliated Hospital of Dalian Medical University, Dalian 116011, Liaoning, China
| | - Jing-Min Li
- Department of Ophthalmology, Institute of Heart and Vascular Diseases, Second Affiliated Hospital of Dalian Medical University, Dalian 116027, Liaoning, China
| | - Qi Zhao
- Department of Ophthalmology, Institute of Heart and Vascular Diseases, Second Affiliated Hospital of Dalian Medical University, Dalian 116027, Liaoning, China
| | - Shu-Bin Guo
- Department of Emergency Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China
| | - Hui-Hua Li
- Department of Emergency Medicine, Beijing Chaoyang Hospital, Capital Medical University, Beijing 100020, China.
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6
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Santiago CP, Keuthan CJ, Boye SL, Boye SE, Imam AA, Ash JD. A Drug-Tunable Gene Therapy for Broad-Spectrum Protection against Retinal Degeneration. Mol Ther 2018; 26:2407-2417. [PMID: 30078764 PMCID: PMC6171322 DOI: 10.1016/j.ymthe.2018.07.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Revised: 07/10/2018] [Accepted: 07/16/2018] [Indexed: 12/27/2022] Open
Abstract
Retinal degenerations are a large cluster of diseases characterized by the irreversible loss of light-sensitive photoreceptors that impairs the vision of 9.1 million people in the US. An attractive treatment option is to use gene therapy to deliver broad-spectrum neuroprotective factors. However, this approach has had limited clinical translation because of the inability to control transgene expression. To address this problem, we generated an adeno-associated virus vector named RPF2 that was engineered to express domains of leukemia inhibitory factor fused to the destabilization domain of bacterial dihydrofolate reductase. Fusion proteins containing the destabilization domain are degraded in mammalian cells but can be stabilized with the binding of the drug trimethoprim. Our data show that expression levels of RPF2 are tightly regulated by the dose of trimethoprim and can be reversed by trimethoprim withdrawal. We further show that stabilized RPF2 can protect photoreceptors and prevent blindness in treated mice.
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Affiliation(s)
- Clayton P Santiago
- Department of Ophthalmology, University of Florida, Gainesville, FL, USA
| | - Casey J Keuthan
- Department of Ophthalmology, University of Florida, Gainesville, FL, USA
| | - Sanford L Boye
- Department of Ophthalmology, University of Florida, Gainesville, FL, USA
| | - Shannon E Boye
- Department of Ophthalmology, University of Florida, Gainesville, FL, USA
| | - Aisha A Imam
- Department of Ophthalmology, University of Florida, Gainesville, FL, USA
| | - John D Ash
- Department of Ophthalmology, University of Florida, Gainesville, FL, USA.
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7
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Segura F, Arines J, Sánchez-Cano A, Perdices L, Orduna-Hospital E, Fuentes-Broto L, Pinilla I. Development of optokinetic tracking software for objective evaluation of visual function in rodents. Sci Rep 2018; 8:10009. [PMID: 29968791 PMCID: PMC6030196 DOI: 10.1038/s41598-018-28394-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 06/20/2018] [Indexed: 12/28/2022] Open
Abstract
The aim of this study was to develop software that performs the optokinetic tracking assessment without the involvement of experimenters to increase the objectivity of the test. To check the effectiveness of the software, several videos were analyzed and the results were compared to those produced by two experimenters. Videos consisted of visual acuity and contrast sensitivity tests on normal animals and pigmented P23H rats (animal model of retinitis pigmentosa). Our software showed a reasonably high success rate: in approximately 78% of the cases, both the software program and the experimenters were in agreement, including the direction of rotation. The software detected 7% false positive cases, 10% false negative cases, and it was wrong in 5% of the cases. Decrease in visual function with age in pigmented P23H rats was observed from the first time interval, although minimum thresholds were found in visual parameters at advanced ages. We developed simple software based on current functions included in the Matlab image processing toolbox that was able to recognize, with a reasonably high percentage of success, the subtle head movements of the rodent produced when visual perception of the optokinetic optotype occurs.
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Affiliation(s)
- Francisco Segura
- Department of Applied Physics, University of Zaragoza, Zaragoza, Spain.,Aragon Institute for Health Research (IIS Aragón), Zaragoza, Spain
| | - Justo Arines
- Department of Applied Physics, University of Santiago de Compostela, Santiago de Compostela, Spain
| | - Ana Sánchez-Cano
- Department of Applied Physics, University of Zaragoza, Zaragoza, Spain.,Aragon Institute for Health Research (IIS Aragón), Zaragoza, Spain
| | - Lorena Perdices
- Aragon Institute for Health Research (IIS Aragón), Zaragoza, Spain.,IACS, Zaragoza, Spain
| | - Elvira Orduna-Hospital
- Aragon Institute for Health Research (IIS Aragón), Zaragoza, Spain.,Department of Physiology and Pharmacology, University of Zaragoza, Zaragoza, Spain
| | - Lorena Fuentes-Broto
- Aragon Institute for Health Research (IIS Aragón), Zaragoza, Spain.,Department of Physiology and Pharmacology, University of Zaragoza, Zaragoza, Spain
| | - Isabel Pinilla
- Aragon Institute for Health Research (IIS Aragón), Zaragoza, Spain. .,IACS, Zaragoza, Spain. .,Department of Surgery, Gynecology and Obstetrics, University of Zaragoza, Zaragoza, Spain.
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8
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Burnight ER, Giacalone JC, Cooke JA, Thompson JR, Bohrer LR, Chirco KR, Drack AV, Fingert JH, Worthington KS, Wiley LA, Mullins RF, Stone EM, Tucker BA. CRISPR-Cas9 genome engineering: Treating inherited retinal degeneration. Prog Retin Eye Res 2018; 65:28-49. [PMID: 29578069 PMCID: PMC8210531 DOI: 10.1016/j.preteyeres.2018.03.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 03/15/2018] [Accepted: 03/18/2018] [Indexed: 12/18/2022]
Abstract
Gene correction is a valuable strategy for treating inherited retinal degenerative diseases, a major cause of irreversible blindness worldwide. Single gene defects cause the majority of these retinal dystrophies. Gene augmentation holds great promise if delivered early in the course of the disease, however, many patients carry mutations in genes too large to be packaged into adeno-associated viral vectors and some, when overexpressed via heterologous promoters, induce retinal toxicity. In addition to the aforementioned challenges, some patients have sustained significant photoreceptor cell loss at the time of diagnosis, rendering gene replacement therapy insufficient to treat the disease. These patients will require cell replacement to restore useful vision. Fortunately, the advent of induced pluripotent stem cell and CRISPR-Cas9 gene editing technologies affords researchers and clinicians a powerful means by which to develop strategies to treat patients with inherited retinal dystrophies. In this review we will discuss the current developments in CRISPR-Cas9 gene editing in vivo in animal models and in vitro in patient-derived cells to study and treat inherited retinal degenerative diseases.
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Affiliation(s)
- Erin R Burnight
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States
| | - Joseph C Giacalone
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States
| | - Jessica A Cooke
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States
| | - Jessica R Thompson
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States
| | - Laura R Bohrer
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States
| | - Kathleen R Chirco
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States
| | - Arlene V Drack
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States
| | - John H Fingert
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States
| | - Kristan S Worthington
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States; Department of Biochemical Engineering, University of Iowa, Iowa City, IA, United States
| | - Luke A Wiley
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States
| | - Robert F Mullins
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States
| | - Edwin M Stone
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States
| | - Budd A Tucker
- Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, United States.
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9
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Xu CL, Park KS, Tsang SH. CRISPR/Cas9 genome surgery for retinal diseases. DRUG DISCOVERY TODAY. TECHNOLOGIES 2018; 28:23-32. [PMID: 30205877 DOI: 10.1016/j.ddtec.2018.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 04/17/2018] [Accepted: 05/29/2018] [Indexed: 12/25/2022]
Abstract
Retinal diseases that impair vision can impose heavy physical and emotional burdens on patients' lives. Currently, clustered regularly interspaced short palindromic repeats (CRISPR) is a prevalent gene-editing tool that can be harnessed to generate disease model organisms for specific retinal diseases, which are useful for elucidating pathophysiology and revealing important links between genetic mutations and phenotypic defects. These retinal disease models are fundamental for testing various therapies and are indispensible for potential future clinical trials. CRISPR-mediated procedures involving CRISPR-associated protein 9 (Cas9) may also be used to edit genome sequences and correct mutations. Thus, if used for future therapies, CRISPR/Cas9 genome surgery could eliminate the need for patients with retinal diseases to undergo repetitive procedures such as drug injections. In this review, we will provide an overview of CRISPR/Cas9, discuss the different types of Cas9, and compare Cas9 to other endonucleases. Furthermore, we will explore the many ways in which researchers are currently utilizing this versatile tool, as CRISPR/Cas9 may have far-reaching effects in the treatment of retinal diseases.
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Affiliation(s)
- Christine L Xu
- Edward S Harkness Eye Institute, New York-Presbyterian Hospital, New York, NY, USA; Jonas Children's Vision Care and the Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia University, New York, NY, USA
| | - Karen Sophia Park
- Edward S Harkness Eye Institute, New York-Presbyterian Hospital, New York, NY, USA; Jonas Children's Vision Care and the Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia University, New York, NY, USA
| | - Stephen H Tsang
- Edward S Harkness Eye Institute, New York-Presbyterian Hospital, New York, NY, USA; Jonas Children's Vision Care and the Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia University, New York, NY, USA; Department of Pathology & Cell Biology, Institute of Human Nutrition, Columbia Stem Cell Initiative, College of Physicians and Surgeons, Columbia University, New York, NY, USA.
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10
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Wang S, Li J, Bai J, Li JM, Che YL, Lin QY, Zhang YL, Li HH. The immunoproteasome subunit LMP10 mediates angiotensin II-induced retinopathy in mice. Redox Biol 2018; 16:129-138. [PMID: 29499566 PMCID: PMC5952914 DOI: 10.1016/j.redox.2018.02.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 02/21/2018] [Accepted: 02/22/2018] [Indexed: 01/27/2023] Open
Abstract
Inflammation has been implicated in a variety of retinal diseases. The immunoproteasome plays a critical role in controlling inflammatory responses, but whether activation of immunoproteasome contributes to angiotensin II (Ang II)-induced retinopathy remains unclear. Hypertensive retinopathy (HR) was induced by infusion of Ang II (3000 ng/kg/min) in wild-type (WT) and immunoproteasome subunit LMP10 knockout (KO) mice for 3 weeks. Changes in retinal morphology, vascular permeability, superoxide production and inflammation were examined by pathological staining. Our results showed that immunoproteasome subunit LMP10 expression and its trypsin-like activity were significantly upregulated in the retinas and serum of Ang II-infused mice and in the serum from patients with hypertensive retinopathy. Moreover, Ang II-infused WT mice showed an increase in the central retinal thickness, vascular permeability, reactive oxygen species (ROS) production and inflammation compared with saline controls, and these effects were significantly attenuated in LMP10 KO mice, but were aggravated in mice intravitreally injected with rAAV2-LMP10. Interestingly, administration of IKKβ specific inhibitor IMD-0354 remarkably blocked an Ang II-induced increase in vascular permeability, oxidative stress and inflammation during retinopathy. Mechanistically, Ang II-induced upregulation of LMP10 promoted PTEN degradation and activation of AKT/IKK signaling, which induced IkBα phosphorylation and subsequent degradation ultimately leading to activation of NF-kB target genes in retinopathy. Therefore, this study provided novel evidence demonstrating that LMP10 is a positive regulator of NF-kB signaling, which contributes to Ang II-induced retinopathy. Strategies for inhibiting LMP10 or IKKβ activity in the eye could serve as a novel therapeutic target for treating hypertensive retinopathy.
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Affiliation(s)
- Shuai Wang
- Department of Ophthalmology, Second Affiliated Hospital of Dalian Medical University, Dalian 116023, China; School of Public Health, Dalian Medical University, Dalian 116004, China
| | - Jing Li
- Department of Cardiology, Institute of Cardiovascular Diseases, First Affiliated Hospital of Dalian Medical University, Dalian 11600, China
| | - Jie Bai
- School of Public Health, Dalian Medical University, Dalian 116004, China
| | - Jing-Min Li
- Department of Ophthalmology, Second Affiliated Hospital of Dalian Medical University, Dalian 116023, China
| | - Yi-Lin Che
- Department of Radiotherapy Oncology, Second Affiliated Hospital of Dalian Medical University, Dalian 116023, China
| | - Qiu-Yue Lin
- Department of Cardiology, Institute of Cardiovascular Diseases, First Affiliated Hospital of Dalian Medical University, Dalian 11600, China
| | - Yun-Long Zhang
- Department of Cardiology, Institute of Cardiovascular Diseases, First Affiliated Hospital of Dalian Medical University, Dalian 11600, China
| | - Hui-Hua Li
- Department of Cardiology, Institute of Cardiovascular Diseases, First Affiliated Hospital of Dalian Medical University, Dalian 11600, China; School of Public Health, Dalian Medical University, Dalian 116004, China.
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11
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LaVail MM, Nishikawa S, Steinberg RH, Naash MI, Duncan JL, Trautmann N, Matthes MT, Yasumura D, Lau-Villacorta C, Chen J, Peterson WM, Yang H, Flannery JG. Phenotypic characterization of P23H and S334ter rhodopsin transgenic rat models of inherited retinal degeneration. Exp Eye Res 2018; 167:56-90. [PMID: 29122605 PMCID: PMC5811379 DOI: 10.1016/j.exer.2017.10.023] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 10/25/2017] [Accepted: 10/31/2017] [Indexed: 02/07/2023]
Abstract
We produced 8 lines of transgenic (Tg) rats expressing one of two different rhodopsin mutations in albino Sprague-Dawley (SD) rats. Three lines were generated with a proline to histidine substitution at codon 23 (P23H), the most common autosomal dominant form of retinitis pigmentosa in the United States. Five lines were generated with a termination codon at position 334 (S334ter), resulting in a C-terminal truncated opsin protein lacking the last 15 amino acid residues and containing all of the phosphorylation sites involved in rhodopsin deactivation, as well as the terminal QVAPA residues important for rhodopsin deactivation and trafficking. The rates of photoreceptor (PR) degeneration in these models vary in proportion to the ratio of mutant to wild-type rhodopsin. The models have been widely studied, but many aspects of their phenotypes have not been described. Here we present a comprehensive study of the 8 Tg lines, including the time course of PR degeneration from the onset to one year of age, retinal structure by light and electron microscopy (EM), hemispheric asymmetry and gradients of rod and cone degeneration, rhodopsin content, gene dosage effect, rapid activation and invasion of the outer retina by presumptive microglia, rod outer segment disc shedding and phagocytosis by the retinal pigmented epithelium (RPE), and retinal function by the electroretinogram (ERG). The biphasic nature of PR cell death was noted, as was the lack of an injury-induced protective response in the rat models. EM analysis revealed the accumulation of submicron vesicular structures in the interphotoreceptor space during the peak period of PR outer segment degeneration in the S334ter lines. This is likely due to the elimination of the trafficking consensus domain as seen before as with other rhodopsin mutants lacking the C-terminal QVAPA. The 8 rhodopsin Tg lines have been, and will continue to be, extremely useful models for the experimental study of inherited retinal degenerations.
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Affiliation(s)
- Matthew M LaVail
- Beckman Vision Center, University of California, San Francisco, San Francisco, CA 94143-0730, USA.
| | - Shimpei Nishikawa
- Beckman Vision Center, University of California, San Francisco, San Francisco, CA 94143-0730, USA.
| | - Roy H Steinberg
- Beckman Vision Center, University of California, San Francisco, San Francisco, CA 94143-0730, USA
| | - Muna I Naash
- Department of Biomedical Engineering, University of Houston, 3517 Cullen Blvd., Room 2011, Houston, TX 77204-5060, USA.
| | - Jacque L Duncan
- Beckman Vision Center, University of California, San Francisco, San Francisco, CA 94143-0730, USA.
| | - Nikolaus Trautmann
- Beckman Vision Center, University of California, San Francisco, San Francisco, CA 94143-0730, USA.
| | - Michael T Matthes
- Beckman Vision Center, University of California, San Francisco, San Francisco, CA 94143-0730, USA.
| | - Douglas Yasumura
- Beckman Vision Center, University of California, San Francisco, San Francisco, CA 94143-0730, USA
| | - Cathy Lau-Villacorta
- Beckman Vision Center, University of California, San Francisco, San Francisco, CA 94143-0730, USA.
| | - Jeannie Chen
- Zilka Neurogenetic Institute, USC Keck School of Medicine, Los Angeles, CA 90089-2821, USA.
| | - Ward M Peterson
- Beckman Vision Center, University of California, San Francisco, San Francisco, CA 94143-0730, USA.
| | - Haidong Yang
- Beckman Vision Center, University of California, San Francisco, San Francisco, CA 94143-0730, USA.
| | - John G Flannery
- School of Optometry, UC Berkeley, Berkeley, CA 94720-2020, USA.
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12
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Bushnell M, Umino Y, Solessio E. A system to measure the pupil response to steady lights in freely behaving mice. J Neurosci Methods 2016; 273:74-85. [PMID: 27494989 DOI: 10.1016/j.jneumeth.2016.08.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 06/27/2016] [Accepted: 08/02/2016] [Indexed: 01/17/2023]
Abstract
BACKGROUND Transgenic mice are widely used for the study of basic visual function and retinal disease, including in psychophysical tests. Mice have a robust pupillary light reflex that controls the amount of light that enters the eye, and the attenuating effects of the pupil must be considered during such tests. Measurement of the size of pupils at various luminance levels requires that mice remain stable over prolonged periods of time; however, sedation of mice with anesthesia and/or manual restraint can influence the size of their pupils. NEW METHOD We present a system to measure the pupillary light response to steady lights of freely behaving mice using a custom-built, portable device that automatically acquires close-up images of their eyes. The device takes advantage of the intrinsic nature of mice to inspect objects of interest and can be used to measure pupillary responses in optomotor or operant behavior testing chambers. RESULTS The size of the pupils in freely behaving mice decreased gradually with luminance from a maximal area in the dark of 3.8mm2 down to a minimum 0.14mm2 at 80 scotopic cd/m2. The data was well fit with a Hill equation with Lo equal to 0.21cd/m2 and coefficient h=0.48. COMPARISON WITH EXISTING METHODS These values agree with prior measurements of the pupillary response of unrestrained mice that use more laborious and time consuming approaches. CONCLUSIONS Our new method facilitates practical, straightforward and accurate measurements of pupillary responses made under the same experimental conditions as those used during psychophysical testing.
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Affiliation(s)
- Mark Bushnell
- Center for Vision Research and SUNY Eye Institute, Department of Ophthalmology, SUNY Upstate Medical University, 750 E. Adams St., Syracuse, New York 13210, USA
| | - Yumiko Umino
- Center for Vision Research and SUNY Eye Institute, Department of Ophthalmology, SUNY Upstate Medical University, 750 E. Adams St., Syracuse, New York 13210, USA
| | - Eduardo Solessio
- Center for Vision Research and SUNY Eye Institute, Department of Ophthalmology, SUNY Upstate Medical University, 750 E. Adams St., Syracuse, New York 13210, USA.
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13
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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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14
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Patel AK, Akinsoji E, Hackam AS. Defining the Relationships Among Retinal Function, Layer Thickness and Visual Behavior During Oxidative Stress-Induced Retinal Degeneration. Curr Eye Res 2015; 41:977-86. [PMID: 26554945 DOI: 10.3109/02713683.2015.1083588] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
PURPOSE The purpose of this study was to identify how changes in retinal structure and function correlate with visual deficits during increasing amounts of retinal degeneration. MATERIALS AND METHODS Retinal degeneration was induced in adult mice by subretinal injections of paraquat (PQ) (0.2-1 mM). Retinal anatomy and photoreceptor layer thickness were quantified by histology and optical coherence tomography (OCT), retinal function was measured using electroretinography (ERG), and visual behavior were measured by optokinetic tracking, at 1 to 3 week post-injury. RESULTS Photoreceptor layer structure, function and visual behavior declined at a linear rate over time following PQ-induced degeneration, with the correlations between outcome measures being lowest at mild injury levels and increasing with injury severity. Overall reductions in visual acuity were highly correlated with declines in retinal thickness (r(2) = 0.78) and function (r(2) = 0.67) and retinal thickness correlated with photoreceptor function (r(2) = 0.72). ERG a-wave scotopic amplitudes showed a stronger correspondence to retinal structure and visual behavior than b-waves. CONCLUSIONS Measurements of photoreceptor loss at the structural and functional levels showed good correspondence with degeneration-associated changes in visual behavior after oxidative stress injury. The results provide new insight about the relative kinetics of measurements of retinal degeneration induced by oxidative stress, which could guide the choice of optimal outcome measurements for other retinal diseases.
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Affiliation(s)
- Amit K Patel
- a Bascom Palmer Eye Institute , University of Miami Miller School of Medicine , Miami , FL , USA
| | - Elizabeth Akinsoji
- a Bascom Palmer Eye Institute , University of Miami Miller School of Medicine , Miami , FL , USA
| | - Abigail S Hackam
- a Bascom Palmer Eye Institute , University of Miami Miller School of Medicine , Miami , FL , USA
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15
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Psychophysical testing in rodent models of glaucomatous optic neuropathy. Exp Eye Res 2015; 141:154-63. [PMID: 26144667 DOI: 10.1016/j.exer.2015.06.025] [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: 11/19/2014] [Revised: 06/08/2015] [Accepted: 06/29/2015] [Indexed: 12/14/2022]
Abstract
Processing of visual information begins in the retina, with photoreceptors converting light stimuli into neural signals. Ultimately, signals are transmitted to the brain through signaling networks formed by interneurons, namely bipolar, horizontal and amacrine cells providing input to retinal ganglion cells (RGCs), which form the optic nerve with their axons. As part of the chronic nature of glaucomatous optic neuropathy, the increasing and irreversible damage and ultimately loss of neurons, RGCs in particular, occurs following progressive damage to the optic nerve head (ONH), eventually resulting in visual impairment and visual field loss. There are two behavioral assays that are typically used to assess visual deficits in glaucoma rodent models, the visual water task and the optokinetic drum. The visual water task can assess an animal's ability to distinguish grating patterns that are associated with an escape from water. The optokinetic drum relies on the optomotor response, a reflex turning of the head and neck in the direction of the visual stimuli, which usually consists of rotating black and white gratings. This reflex is a physiological response critical for keeping the image stable on the retina. Driven initially by the neuronal input from direction-selective RGCs, this reflex is comprised of a number of critical sensory and motor elements. In the presence of repeatable and defined stimuli, this reflex is extremely well suited to analyze subtle changes in the circuitry and performance of retinal neurons. Increasing the cycles of these alternating gratings per degree, or gradually reducing the contrast of the visual stimuli, threshold levels can be determined at which the animal is no longer tracking the stimuli, and thereby visual function of the animal can be determined non-invasively. Integrating these assays into an array of outcome measures that determine multiple aspects of visual function is a central goal in vision research and can be realized, for example, by the combination of measuring optomotor reflex function with electroretinograms (ERGs) and optical coherence tomography (OCT) of the retina. These structure-function correlations in vivo are urgently needed to identify disease mechanisms as potential new targets for drug development. Such a combination of the experimental assessment of the optokinetic reflex (OKR) or optomotor response (OMR) with other measures of retinal structure and function is especially valuable for research on GON. The chronic progression of the disease is characterized by a gradual decrease in function accompanied by a concomitant increase in structural damage to the retina, therefore the assessment of subtle changes is key to determining the success of novel intervention strategies.
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16
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Laver CRJ, Metcalfe AL, Szczygiel L, Yanai A, Sarunic MV, Gregory-Evans K. Bimodal in vivo imaging provides early assessment of stem-cell-based photoreceptor engraftment. Eye (Lond) 2015; 29:681-90. [PMID: 25771816 DOI: 10.1038/eye.2015.24] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Accepted: 01/23/2015] [Indexed: 11/09/2022] Open
Abstract
PURPOSE Subretinal transplantation of stem-cell-derived photoreceptor precursor cells (PPCs) is a promising and innovative approach to treating a range of blinding diseases. However, common barriers to efficient preclinical transplantation comes in the form of suboptimal graft architecture, limited graft survival, and immune-rejection, each of which cannot be assessed using conventional in vivo imaging (i.e., rodent ophthalmoscopy). With the majority of PPCs reported to die within the first few weeks after transplantation, understanding the mechanisms of graft failure, and ultimately devising preventative methods, currently relies on lengthy end point histology. To address these limitations, we hypothesized that combining two imaging modalities, optical coherence tomography (OCT) and fluorescence confocal scanning laser ophthalmoscopy (fcSLO), could provide a more rapid and comprehensive view of PPC engraftment. METHODS Human ESC-derived PPCs were transplanted into 15 retinal dystrophic rats that underwent bimodal imaging at 0, 8, and 15 days posttransplant. RESULTS Bimodal imaging provided serial detection of graft: placement, architecture, and survival; each undetectable under ophthalmoscopy. Bimodal imaging determined graft placement to be either: subretinal (n=7), choroidal (n=4), or vitreal (n=4) indicating neural retinal perforation. Graft architecture was highly variable at the time of transplantation, with notable redistribution over time, while complete, or near complete, graft loss was observed in the majority of recipients after day 8. Of particular importance was detection of vitreal aggregates overlying the graft-possibly an indicator of host-site inflammation and rejection. CONCLUSION Early real-time feedback of engraftment has the potential to greatly increase efficiency of preclinical trials in cell-based retinal therapeutics.
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Affiliation(s)
- C R J Laver
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - A L Metcalfe
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - L Szczygiel
- Department of Molecular Biology and Biochemistry, Faculty of Science, Simon Fraser University, Burnaby, BC, Canada
| | - A Yanai
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
| | - M V Sarunic
- School of Engineering Science, Faculty of Applied Science, Simon Fraser University, Burnaby, BC, Canada
| | - K Gregory-Evans
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada
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17
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Shi Q, Stell WK. Die Fledermaus: regarding optokinetic contrast sensitivity and light-adaptation, chicks are mice with wings. PLoS One 2013; 8:e75375. [PMID: 24098693 PMCID: PMC3787091 DOI: 10.1371/journal.pone.0075375] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Accepted: 08/14/2013] [Indexed: 01/27/2023] Open
Abstract
BACKGROUND Through adaptation, animals can function visually under an extremely broad range of light intensities. Light adaptation starts in the retina, through shifts in photoreceptor sensitivity and kinetics plus modulation of visual processing in retinal circuits. Although considerable research has been conducted on retinal adaptation in nocturnal species with rod-dominated retinas, such as the mouse, little is known about how cone-dominated avian retinas adapt to changes in mean light intensity. METHODOLOGY/PRINCIPAL FINDINGS We used the optokinetic response to characterize contrast sensitivity (CS) in the chick retina as a function of spatial frequency and temporal frequency at different mean light intensities. We found that: 1) daytime, cone-driven CS was tuned to spatial frequency; 2) nighttime, presumably rod-driven CS was tuned to temporal frequency and spatial frequency; 3) daytime, presumably cone-driven CS at threshold intensity was invariant with temporal and spatial frequency; and 4) daytime photopic CS was invariant with clock time. CONCLUSION/SIGNIFICANCE Light- and dark-adaptational changes in CS were investigated comprehensively for the first time in the cone-dominated retina of an avian, diurnal species. The chick retina, like the mouse retina, adapts by using a "day/night" or "cone/rod" switch in tuning preference during changes in lighting conditions. The chick optokinetic response is an attractive model for noninvasive, behavioral studies of adaptation in retinal circuitry in health and disease.
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Affiliation(s)
- Qing Shi
- Neuroscience Graduate Program, University of Calgary Faculty of Medicine, Calgary, Alberta, Canada
| | - William K. Stell
- Department of Cell Biology and Anatomy, and Department of Surgery, and Hotchkiss Brain Institute and Alberta Children’s Hospital Research Institute; University of Calgary Faculty of Medicine, Calgary, Alberta, Canada
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