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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: 57] [Impact Index Per Article: 9.5] [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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52
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DiCarlo JE, Mahajan VB, Tsang SH. Gene therapy and genome surgery in the retina. J Clin Invest 2018; 128:2177-2188. [PMID: 29856367 DOI: 10.1172/jci120429] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Precision medicine seeks to treat disease with molecular specificity. Advances in genome sequence analysis, gene delivery, and genome surgery have allowed clinician-scientists to treat genetic conditions at the level of their pathology. As a result, progress in treating retinal disease using genetic tools has advanced tremendously over the past several decades. Breakthroughs in gene delivery vectors, both viral and nonviral, have allowed the delivery of genetic payloads in preclinical models of retinal disorders and have paved the way for numerous successful clinical trials. Moreover, the adaptation of CRISPR-Cas systems for genome engineering have enabled the correction of both recessive and dominant pathogenic alleles, expanding the disease-modifying power of gene therapies. Here, we highlight the translational progress of gene therapy and genome editing of several retinal disorders, including RPE65-, CEP290-, and GUY2D-associated Leber congenital amaurosis, as well as choroideremia, achromatopsia, Mer tyrosine kinase- (MERTK-) and RPGR X-linked retinitis pigmentosa, Usher syndrome, neovascular age-related macular degeneration, X-linked retinoschisis, Stargardt disease, and Leber hereditary optic neuropathy.
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Affiliation(s)
- James E DiCarlo
- Jonas Children's Vision Care and Bernard and Shirlee Brown Glaucoma Laboratory, Columbia Stem Cell Initiative, Departments of Ophthalmology, Pathology and Cell Biology, Institute of Human Nutrition, College of Physicians and Surgeons, Columbia University, New York, New York, USA.,Edward S. Harkness Eye Institute, New York-Presbyterian Hospital, New York, New York, USA
| | - Vinit B Mahajan
- Omics Laboratory, Byers Eye Institute, Department of Ophthalmology, Stanford University, Palo Alto, California, USA.,Veterans Affairs Palo Alto Health Care System, Palo Alto, California, USA
| | - Stephen H Tsang
- Jonas Children's Vision Care and Bernard and Shirlee Brown Glaucoma Laboratory, Columbia Stem Cell Initiative, Departments of Ophthalmology, Pathology and Cell Biology, Institute of Human Nutrition, College of Physicians and Surgeons, Columbia University, New York, New York, USA.,Edward S. Harkness Eye Institute, New York-Presbyterian Hospital, New York, New York, USA
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53
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Shimada H, Lu Q, Insinna-Kettenhofen C, Nagashima K, English MA, Semler EM, Mahgerefteh J, Cideciyan AV, Li T, Brooks BP, Gunay-Aygun M, Jacobson SG, Cogliati T, Westlake CJ, Swaroop A. In Vitro Modeling Using Ciliopathy-Patient-Derived Cells Reveals Distinct Cilia Dysfunctions Caused by CEP290 Mutations. Cell Rep 2018; 20:384-396. [PMID: 28700940 DOI: 10.1016/j.celrep.2017.06.045] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Revised: 05/03/2017] [Accepted: 06/19/2017] [Indexed: 02/06/2023] Open
Abstract
Mutations in CEP290, a transition zone protein in primary cilia, cause diverse ciliopathies, including Leber congenital amaurosis (LCA) and Joubert-syndrome and related disorders (JSRD). We examined cilia biogenesis and function in cells derived from CEP290-LCA and CEP290-JSRD patients. CEP290 protein was reduced in LCA fibroblasts with no detectable impact on cilia; however, optic cups derived from induced pluripotent stem cells (iPSCs) of CEP290-LCA patients displayed less developed photoreceptor cilia. Lack of CEP290 in JSRD fibroblasts resulted in abnormal cilia and decreased ciliogenesis. We observed selectively reduced localization of ADCY3 and ARL13B. Notably, Hedgehog signaling was augmented in CEP290-JSRD because of enhanced ciliary transport of Smoothened and GPR161. These results demonstrate a direct correlation between the extent of ciliogenesis defects in fibroblasts and photoreceptors with phenotypic severity in JSRD and LCA, respectively, and strengthen the role of CEP290 as a selective ciliary gatekeeper for transport of signaling molecules in and out of the cilium.
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Affiliation(s)
- Hiroko Shimada
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Quanlong Lu
- Laboratory of Cell and Developmental Signaling, National Cancer Institute - Frederick, Frederick, MD 21702, USA
| | | | - Kunio Nagashima
- Electron Microscope Laboratory, Leidos Biomedical Research, Inc., National Cancer Institute - Frederick, Frederick, MD 21702, USA
| | - Milton A English
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Elizabeth M Semler
- Laboratory of Cell and Developmental Signaling, National Cancer Institute - Frederick, Frederick, MD 21702, USA
| | - Jacklyn Mahgerefteh
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Artur V Cideciyan
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Tiansen Li
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Brian P Brooks
- Pediatric, Developmental, and Genetic Eye Disease Branch, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Meral Gunay-Aygun
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA; Department of Pediatrics, McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Samuel G Jacobson
- Department of Ophthalmology, Scheie Eye Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Tiziana Cogliati
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Christopher J Westlake
- Laboratory of Cell and Developmental Signaling, National Cancer Institute - Frederick, Frederick, MD 21702, USA.
| | - Anand Swaroop
- Neurobiology-Neurodegeneration and Repair Laboratory, National Eye Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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54
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Rathod R, Surendran H, Battu R, Desai J, Pal R. Induced pluripotent stem cells (iPSC)-derived retinal cells in disease modeling and regenerative medicine. J Chem Neuroanat 2018; 95:81-88. [PMID: 29448001 DOI: 10.1016/j.jchemneu.2018.02.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 02/02/2018] [Accepted: 02/10/2018] [Indexed: 12/19/2022]
Abstract
Retinal degenerative disorders are a leading cause of the inherited, irreversible and incurable vision loss. While various rodent model systems have provided crucial information in this direction, lack of disease-relevant tissue availability and species-specific differences have proven to be a major roadblock. Human induced pluripotent stem cells (iPSC) have opened up a whole new avenue of possibilities not just in understanding the disease mechanism but also potential therapeutic approaches towards a cure. In this review, we have summarized recent advances in the methods of deriving retinal cell types from iPSCs which can serve as a renewable source of disease-relevant cell population for basic as well as translational studies. We also provide an overview of the ongoing efforts towards developing a suitable in vitro model for modeling retinal degenerative diseases. This basic understanding in turn has contributed to advances in translational goals such as drug screening and cell-replacement therapies. Furthermore we discuss gene editing approaches for autologous repair of genetic disorders and allogeneic transplantation of stem cell-based retinal derivatives for degenerative disorders with an ultimate goal to restore vision. It is pertinent to note however, that these exciting new developments throw up several challenges that need to be overcome before their full clinical potential can be realized.
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Affiliation(s)
- Reena Rathod
- Eyestem Research Private Limited, Centre for Cellular and Molecular Platforms (CCAMP), National Centre for Biological Sciences-Tata Institute of Fundamental Research (NCBS-TIFR), GKVK Campus, Bangalore, 560065, India
| | - Harshini Surendran
- Eyestem Research Private Limited, Centre for Cellular and Molecular Platforms (CCAMP), National Centre for Biological Sciences-Tata Institute of Fundamental Research (NCBS-TIFR), GKVK Campus, Bangalore, 560065, India
| | - Rajani Battu
- Eyestem Research Private Limited, Centre for Cellular and Molecular Platforms (CCAMP), National Centre for Biological Sciences-Tata Institute of Fundamental Research (NCBS-TIFR), GKVK Campus, Bangalore, 560065, India; Centre for Eye Genetics and Research, Cytecare Hospital, Bellary Road, Bangalore, 560064, India
| | - Jogin Desai
- Eyestem Research Private Limited, Centre for Cellular and Molecular Platforms (CCAMP), National Centre for Biological Sciences-Tata Institute of Fundamental Research (NCBS-TIFR), GKVK Campus, Bangalore, 560065, India; Centre for Eye Genetics and Research, Cytecare Hospital, Bellary Road, Bangalore, 560064, India
| | - Rajarshi Pal
- Eyestem Research Private Limited, Centre for Cellular and Molecular Platforms (CCAMP), National Centre for Biological Sciences-Tata Institute of Fundamental Research (NCBS-TIFR), GKVK Campus, Bangalore, 560065, India.
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55
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Leber Congenital Amaurosis Associated with Mutations in CEP290, Clinical Phenotype, and Natural History in Preparation for Trials of Novel Therapies. Ophthalmology 2018; 125:894-903. [PMID: 29398085 PMCID: PMC5974693 DOI: 10.1016/j.ophtha.2017.12.013] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 12/01/2017] [Accepted: 12/07/2017] [Indexed: 11/21/2022] Open
Abstract
PURPOSE To investigate and describe in detail the demographics, functional and anatomic characteristics, and clinical course of Leber congenital amaurosis (LCA) associated with mutations in the CEP290 gene (LCA-CEP290) in a large cohort of adults and children. DESIGN Retrospective case series. PARTICIPANTS Patients with mutations in CEP290 identified at a single UK referral center. METHODS Review of case notes and results of retinal imaging (color fundus photography, fundus autofluorescence [FAF] imaging, OCT), electrophysiologic assessment, and molecular genetic testing. MAIN OUTCOME MEASURES Molecular genetic testing, clinical findings including visual acuity and retinal imaging, and electrophysiologic assessment. RESULTS Forty patients with LCA-CEP290 were identified. The deep intronic mutation c.2991+1655 A>G was the most common disease-causing variant (23/40 patients) identified in the compound heterozygous state in 20 patients (50%) and homozygous in 2 patients (5%). Visual acuity (VA) varied from 6/9 to no perception of light, and only 2 of 12 patients with longitudinal VA data showed deterioration in VA in their better-seeing eye over time. A normal fundus was found at diagnosis in younger patients (mean age, 1.9 years), with older patients showing white flecks (mean age, 5.9 years) or pigmentary retinopathy (mean age, 21.7 years). Eleven of 12 patients (92%) with OCT imaging had preservation of foveal architecture. Ten of 12 patients (83%) with FAF imaging had a perifoveal hyperautofluorescent ring. Having 2 nonsense CEP290 mutations was associated with worse final VA and the presence of nonocular features. CONCLUSIONS Detailed analysis of the clinical phenotype of LCA-CEP290 in a large cohort confirms that there is a window of opportunity in childhood for therapeutic intervention based on relative structural preservation in the central cone-rich retina in a significant proportion of patients, with the majority harboring the deep intronic variant potentially tractable to several planned gene editing approaches.
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56
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Kumaran N, Smith AJ, Michaelides M, Ali R, Bainbridge J. Gene therapy for Leber congenital amaurosis. EXPERT REVIEW OF OPHTHALMOLOGY 2018. [DOI: 10.1080/17469899.2018.1429916] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Neruban Kumaran
- NIHR Biomedical Research Centre for Ophthalmology, UCL and Moorfields Eye Hospital, London, UK
| | - Alexander J. Smith
- NIHR Biomedical Research Centre for Ophthalmology, UCL and Moorfields Eye Hospital, London, UK
| | - Michel Michaelides
- NIHR Biomedical Research Centre for Ophthalmology, UCL and Moorfields Eye Hospital, London, UK
| | - Robin Ali
- NIHR Biomedical Research Centre for Ophthalmology, UCL and Moorfields Eye Hospital, London, UK
| | - James Bainbridge
- NIHR Biomedical Research Centre for Ophthalmology, UCL and Moorfields Eye Hospital, London, UK
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57
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Zhang W, Li L, Su Q, Gao G, Khanna H. Gene Therapy Using a miniCEP290 Fragment Delays Photoreceptor Degeneration in a Mouse Model of Leber Congenital Amaurosis. Hum Gene Ther 2018; 29:42-50. [PMID: 28679290 PMCID: PMC5770090 DOI: 10.1089/hum.2017.049] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 06/27/2017] [Indexed: 12/25/2022] Open
Abstract
Mutations in the cilia-centrosomal protein CEP290 are frequently observed in autosomal recessive childhood blindness disorder Leber congenital amaurosis (LCA). No treatment or cure currently exists for this disorder. The Cep290rd16 (retinal degeneration 16) mouse (a model of LCA) carries a mutation in the Cep290 gene. This mutation leads to shorter cilia formation and defective photoreceptor structure and function. A roadblock to developing a gene replacement strategy for CEP290 using conventional adeno-associated virus (AAV) vectors is its large size. The identification and characterization is reported of a miniCEP290 gene that is amenable to AAV2/8-mediated delivery and delaying retinal degeneration in the Cep290rd16 mice. Using the ability of Cep290rd16 mouse embryonic fibroblasts to from shorter cilia as a platform, a human CEP290 domain encoded by amino acids 580-1180 (miniCEP290580-1180) was identified that can recover the cilia length in vitro. Furthermore, subretinal injection of AAV particles carrying the cDNA expressing miniCEP290580-1180 into neonatal Cep290rd16 mice resulted in significantly improved photoreceptor survival, morphology, and function compared to control injected mice. These studies show the potential of using a truncated CEP290 to treat this fast progressing and devastating disease.
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Affiliation(s)
- Wei Zhang
- Department of Ophthalmology, UMASS Medical School, Worcester, Massachusetts
| | - Linjing Li
- Department of Ophthalmology, UMASS Medical School, Worcester, Massachusetts
| | - Qin Su
- Horae Gene Therapy Center, UMASS Medical School, Worcester, Massachusetts
| | - Guangping Gao
- Horae Gene Therapy Center, UMASS Medical School, Worcester, Massachusetts
| | - Hemant Khanna
- Department of Ophthalmology, UMASS Medical School, Worcester, Massachusetts
- Horae Gene Therapy Center, UMASS Medical School, Worcester, Massachusetts
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58
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Di Iorio V, Karali M, Brunetti-Pierri R, Filippelli M, Di Fruscio G, Pizzo M, Mutarelli M, Nigro V, Testa F, Banfi S, Simonelli F. Clinical and Genetic Evaluation of a Cohort of Pediatric Patients with Severe Inherited Retinal Dystrophies. Genes (Basel) 2017; 8:genes8100280. [PMID: 29053603 PMCID: PMC5664130 DOI: 10.3390/genes8100280] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Revised: 10/02/2017] [Accepted: 10/13/2017] [Indexed: 12/30/2022] Open
Abstract
We performed a clinical and genetic characterization of a pediatric cohort of patients with inherited retinal dystrophy (IRD) to identify the most suitable cases for gene therapy. The cohort comprised 43 patients, aged between 2 and 18 years, with severe isolated IRD at the time of presentation. The ophthalmological characterization also included assessment of the photoreceptor layer integrity in the macular region (ellipsoid zone (EZ) band). In parallel, we carried out a targeted, next-generation sequencing (NGS)-based analysis using a panel that covers over 150 genes with either an established or a candidate role in IRD pathogenesis. Based on the ophthalmological assessment, the cohort was composed of 24 Leber congenital amaurosis, 14 early onset retinitis pigmentosa, and 5 achromatopsia patients. We identified causative mutations in 58.1% of the cases. We also found novel genotype-phenotype correlations in patients harboring mutations in the CEP290 and CNGB3 genes. The EZ band was detectable in 40% of the analyzed cases, also in patients with genotypes usually associated with severe clinical manifestations. This study provides the first detailed clinical-genetic assessment of severe IRDs with infantile onset and lays the foundation of a standardized protocol for the selection of patients that are more likely to benefit from gene replacement therapeutic approaches.
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Affiliation(s)
- Valentina Di Iorio
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania Luigi Vanvitelli, via Pansini 5, Naples 80131, Italy.
| | - Marianthi Karali
- Medical Genetics, Department of Biochemistry, Biophysics and General Pathology, Università degli Studi della Campania Luigi Vanvitelli, via Luigi De Crecchio 7, Naples 80138, Italy.
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, Pozzuoli 80078, Italy.
| | - Raffaella Brunetti-Pierri
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania Luigi Vanvitelli, via Pansini 5, Naples 80131, Italy.
| | - Mariaelena Filippelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania Luigi Vanvitelli, via Pansini 5, Naples 80131, Italy.
| | - Giuseppina Di Fruscio
- Medical Genetics, Department of Biochemistry, Biophysics and General Pathology, Università degli Studi della Campania Luigi Vanvitelli, via Luigi De Crecchio 7, Naples 80138, Italy.
| | - Mariateresa Pizzo
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, Pozzuoli 80078, Italy.
| | - Margherita Mutarelli
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, Pozzuoli 80078, Italy.
| | - Vincenzo Nigro
- Medical Genetics, Department of Biochemistry, Biophysics and General Pathology, Università degli Studi della Campania Luigi Vanvitelli, via Luigi De Crecchio 7, Naples 80138, Italy.
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, Pozzuoli 80078, Italy.
| | - Francesco Testa
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania Luigi Vanvitelli, via Pansini 5, Naples 80131, Italy.
| | - Sandro Banfi
- Medical Genetics, Department of Biochemistry, Biophysics and General Pathology, Università degli Studi della Campania Luigi Vanvitelli, via Luigi De Crecchio 7, Naples 80138, Italy.
- Telethon Institute of Genetics and Medicine, via Campi Flegrei 34, Pozzuoli 80078, Italy.
| | - Francesca Simonelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, Università degli Studi della Campania Luigi Vanvitelli, via Pansini 5, Naples 80131, Italy.
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CLINICAL PROGRESS IN INHERITED RETINAL DEGENERATIONS: GENE THERAPY CLINICAL TRIALS AND ADVANCES IN GENETIC SEQUENCING. Retina 2017; 37:417-423. [PMID: 27753762 DOI: 10.1097/iae.0000000000001341] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
PURPOSE Inherited retinal dystrophies are a significant cause of vision loss and are characterized by the loss of photoreceptors and the retinal pigment epithelium (RPE). Mutations in approximately 250 genes cause inherited retinal degenerations with a high degree of genetic heterogeneity. New techniques in next-generation sequencing are allowing the comprehensive analysis of all retinal disease genes thus changing the approach to the molecular diagnosis of inherited retinal dystrophies. This review serves to analyze clinical progress in genetic diagnostic testing and implications for retinal gene therapy. METHODS A literature search of PubMed and OMIM was conducted to relevant articles in inherited retinal dystrophies. RESULTS Next-generation genetic sequencing allows the simultaneous analysis of all the approximately 250 genes that cause inherited retinal dystrophies. Reported diagnostic rates range are high and range from 51% to 57%. These new sequencing tools are highly accurate with sensitivities of 97.9% and specificities of 100%. Retinal gene therapy clinical trials are underway for multiple genes including RPE65, ABCA4, CHM, RS1, MYO7A, CNGA3, CNGB3, ND4, and MERTK for which a molecular diagnosis may be beneficial for patients. CONCLUSION Comprehensive next-generation genetic sequencing of all retinal dystrophy genes is changing the paradigm for how retinal specialists perform genetic testing for inherited retinal degenerations. Not only are high diagnostic yields obtained, but mutations in genes with novel clinical phenotypes are also identified. In the era of retinal gene therapy clinical trials, identifying specific genetic defects will increasingly be of use to identify patients who may enroll in clinical studies and benefit from novel therapies.
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60
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Burnight ER, Gupta M, Wiley LA, Anfinson KR, Tran A, Triboulet R, Hoffmann JM, Klaahsen DL, Andorf JL, Jiao C, Sohn EH, Adur MK, Ross JW, Mullins RF, Daley GQ, Schlaeger TM, Stone EM, Tucker BA. Using CRISPR-Cas9 to Generate Gene-Corrected Autologous iPSCs for the Treatment of Inherited Retinal Degeneration. Mol Ther 2017; 25:1999-2013. [PMID: 28619647 PMCID: PMC5589061 DOI: 10.1016/j.ymthe.2017.05.015] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Revised: 05/22/2017] [Accepted: 05/22/2017] [Indexed: 01/20/2023] Open
Abstract
Patient-derived induced pluripotent stem cells (iPSCs) hold great promise for autologous cell replacement. However, for many inherited diseases, treatment will likely require genetic repair pre-transplantation. Genome editing technologies are useful for this application. The purpose of this study was to develop CRISPR-Cas9-mediated genome editing strategies to target and correct the three most common types of disease-causing variants in patient-derived iPSCs: (1) exonic, (2) deep intronic, and (3) dominant gain of function. We developed a homology-directed repair strategy targeting a homozygous Alu insertion in exon 9 of male germ cell-associated kinase (MAK) and demonstrated restoration of the retinal transcript and protein in patient cells. We generated a CRISPR-Cas9-mediated non-homologous end joining (NHEJ) approach to excise a major contributor to Leber congenital amaurosis, the IVS26 cryptic-splice mutation in CEP290, and demonstrated correction of the transcript and protein in patient iPSCs. Lastly, we designed allele-specific CRISPR guides that selectively target the mutant Pro23His rhodopsin (RHO) allele, which, following delivery to both patient iPSCs in vitro and pig retina in vivo, created a frameshift and premature stop that would prevent transcription of the disease-causing variant. The strategies developed in this study will prove useful for correcting a wide range of genetic variants in genes that cause inherited retinal degeneration.
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Affiliation(s)
- Erin R Burnight
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Manav Gupta
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital and Dana-Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 01451, USA
| | - Luke A Wiley
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Kristin R Anfinson
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Audrey Tran
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital and Dana-Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 01451, USA
| | - Robinson Triboulet
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital and Dana-Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 01451, USA
| | - Jeremy M Hoffmann
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Darcey L Klaahsen
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Jeaneen L Andorf
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Chunhua Jiao
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Elliott H Sohn
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Malavika K Adur
- Department of Animal Sciences, Iowa State University, Ames, IA 50011, USA
| | - Jason W Ross
- Department of Animal Sciences, Iowa State University, Ames, IA 50011, USA
| | - Robert F Mullins
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - George Q Daley
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital and Dana-Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 01451, USA
| | - Thorsten M Schlaeger
- Stem Cell Program and Division of Hematology/Oncology, Boston Children's Hospital and Dana-Farber Cancer Institute, Howard Hughes Medical Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA 01451, USA
| | - Edwin M Stone
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA
| | - Budd A Tucker
- Stephen A. Wynn Institute for Vision Research and Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, IA 52241, USA.
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61
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Wiley LA, Anfinson KR, Cranston CM, Kaalberg EE, Collins MM, Mullins RF, Stone EM, Tucker BA. Generation of Xeno-Free, cGMP-Compliant Patient-Specific iPSCs from Skin Biopsy. ACTA ACUST UNITED AC 2017; 42:4A.12.1-4A.12.14. [PMID: 28806854 DOI: 10.1002/cpsc.30] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
This unit describes protocols for the generation of clinical-grade patient-specific induced pluripotent stem cell (iPSC)-derived retinal cells from patients with inherited retinal degenerative blindness. Specifically, we describe how, using xeno-free reagents in an ISO class 5 environment, one can isolate and culture dermal fibroblasts, generate iPSCs, and derive autologous retinal cells via 3-D differentiation. The universal methods described herein for the isolation of dermal fibroblasts and generation of iPSCs can be employed regardless of disease, tissue, or cell type of interest. © 2017 by John Wiley & Sons, Inc.
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Affiliation(s)
- Luke A Wiley
- Stephen A. Wynn, Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa.,Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Kristin R Anfinson
- Stephen A. Wynn, Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa.,Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Cathryn M Cranston
- Stephen A. Wynn, Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa.,Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Emily E Kaalberg
- Stephen A. Wynn, Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa.,Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Malia M Collins
- Stephen A. Wynn, Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa.,Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Robert F Mullins
- Stephen A. Wynn, Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa.,Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Edwin M Stone
- Stephen A. Wynn, Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa.,Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Budd A Tucker
- Stephen A. Wynn, Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa.,Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
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62
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Kumaran N, Moore AT, Weleber RG, Michaelides M. Leber congenital amaurosis/early-onset severe retinal dystrophy: clinical features, molecular genetics and therapeutic interventions. Br J Ophthalmol 2017; 101:1147-1154. [PMID: 28689169 PMCID: PMC5574398 DOI: 10.1136/bjophthalmol-2016-309975] [Citation(s) in RCA: 195] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 04/26/2017] [Accepted: 04/30/2017] [Indexed: 12/29/2022]
Abstract
Leber congenital amaurosis (LCA) and early-onset severe retinal dystrophy (EOSRD) are both genetically and phenotypically heterogeneous, and characterised clinically by severe congenital/early infancy visual loss, nystagmus, amaurotic pupils and markedly reduced/absent full-field electroretinograms. The vast genetic heterogeneity of inherited retinal disease has been established over the last 10 - 20 years, with disease-causing variants identified in 25 genes to date associated with LCA/EOSRD, accounting for 70–80% of cases, with thereby more genes yet to be identified. There is now far greater understanding of the structural and functional associations seen in the various LCA/EOSRD genotypes. Subsequent development/characterisation of LCA/EOSRD animal models has shed light on the underlying pathogenesis and allowed the demonstration of successful rescue with gene replacement therapy and pharmacological intervention in multiple models. These advancements have culminated in more than 12 completed, ongoing and anticipated phase I/II and phase III gene therapy and pharmacological human clinical trials. This review describes the clinical and genetic characteristics of LCA/EOSRD and the differential diagnoses to be considered. We discuss in further detail the diagnostic clinical features, pathophysiology, animal models and human treatment studies and trials, in the more common genetic subtypes and/or those closest to intervention.
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Affiliation(s)
- Neruban Kumaran
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Anthony T Moore
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK.,University of California San Francisco, San Francisco CA, California, USA
| | - Richard G Weleber
- Casey Eye Institute, Oregon Health and Science University, Portland, Oregon, USA
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
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63
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May-Simera H, Nagel-Wolfrum K, Wolfrum U. Cilia - The sensory antennae in the eye. Prog Retin Eye Res 2017; 60:144-180. [PMID: 28504201 DOI: 10.1016/j.preteyeres.2017.05.001] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 05/04/2017] [Accepted: 05/08/2017] [Indexed: 12/21/2022]
Abstract
Cilia are hair-like projections found on almost all cells in the human body. Originally believed to function merely in motility, the function of solitary non-motile (primary) cilia was long overlooked. Recent research has demonstrated that primary cilia function as signalling hubs that sense environmental cues and are pivotal for organ development and function, tissue hoemoestasis, and maintenance of human health. Cilia share a common anatomy and their diverse functional features are achieved by evolutionarily conserved functional modules, organized into sub-compartments. Defects in these functional modules are responsible for a rapidly growing list of human diseases collectively termed ciliopathies. Ocular pathogenesis is common in virtually all classes of syndromic ciliopathies, and disruptions in cilia genes have been found to be causative in a growing number of non-syndromic retinal dystrophies. This review will address what is currently known about cilia contribution to visual function. We will focus on the molecular and cellular functions of ciliary proteins and their role in the photoreceptor sensory cilia and their visual phenotypes. We also highlight other ciliated cell types in tissues of the eye (e.g. lens, RPE and Müller glia cells) discussing their possible contribution to disease progression. Progress in basic research on the cilia function in the eye is paving the way for therapeutic options for retinal ciliopathies. In the final section we describe the latest advancements in gene therapy, read-through of non-sense mutations and stem cell therapy, all being adopted to treat cilia dysfunction in the retina.
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Affiliation(s)
- Helen May-Simera
- Institute of Molecular Physiology, Cilia Biology, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - Kerstin Nagel-Wolfrum
- Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany
| | - Uwe Wolfrum
- Institute of Molecular Physiology, Molecular Cell Biology, Johannes Gutenberg-Universität Mainz, 55099 Mainz, Germany.
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64
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Ruan GX, Barry E, Yu D, Lukason M, Cheng SH, Scaria A. CRISPR/Cas9-Mediated Genome Editing as a Therapeutic Approach for Leber Congenital Amaurosis 10. Mol Ther 2017; 25:331-341. [PMID: 28109959 PMCID: PMC5368591 DOI: 10.1016/j.ymthe.2016.12.006] [Citation(s) in RCA: 186] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2016] [Revised: 12/06/2016] [Accepted: 12/06/2016] [Indexed: 12/18/2022] Open
Abstract
As the most common subtype of Leber congenital amaurosis (LCA), LCA10 is a severe retinal dystrophy caused by mutations in the CEP290 gene. The most frequent mutation found in patients with LCA10 is a deep intronic mutation in CEP290 that generates a cryptic splice donor site. The large size of the CEP290 gene prevents its use in adeno-associated virus (AAV)-mediated gene augmentation therapy. Here, we show that targeted genomic deletion using the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 system represents a promising therapeutic approach for the treatment of patients with LCA10 bearing the CEP290 splice mutation. We generated a cellular model of LCA10 by introducing the CEP290 splice mutation into 293FT cells and we showed that guide RNA pairs coupled with SpCas9 were highly efficient at removing the intronic splice mutation and restoring the expression of wild-type CEP290. In addition, we demonstrated that a dual AAV system could effectively delete an intronic fragment of the Cep290 gene in the mouse retina. To minimize the immune response to prolonged expression of SpCas9, we developed a self-limiting CRISPR/Cas9 system that minimizes the duration of SpCas9 expression. These results support further studies to determine the therapeutic potential of CRISPR/Cas9-based strategies for the treatment of patients with LCA10.
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Affiliation(s)
- Guo-Xiang Ruan
- Rare Diseases, Sanofi Genzyme, Framingham, MA 01701, USA.
| | | | - Dan Yu
- Rare Diseases, Sanofi Genzyme, Framingham, MA 01701, USA
| | | | - Seng H Cheng
- Rare Diseases, Sanofi Genzyme, Framingham, MA 01701, USA
| | - Abraham Scaria
- Rare Diseases, Sanofi Genzyme, Framingham, MA 01701, USA
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65
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Coussa RG, Lopez Solache I, Koenekoop RK. Leber congenital amaurosis, from darkness to light: An ode to Irene Maumenee. Ophthalmic Genet 2017; 38:7-15. [PMID: 28095138 DOI: 10.1080/13816810.2016.1275021] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
This article is dedicated to Irene Hussels Maumenee, Professor of Human Genetics and Ophthalmology, Johns Hopkins' Wilmer Eye Institute, Ocular Genetics Fellowship director in 1994-1995. Leber congenital amaurosis (LCA) has almost come full circle, from a profound and molecularly uncharacterized form of congenital retinal blindness to one in which a large number of causative genes and disease pathways are known, and the world's first human retinal disease to be treated by gene therapy. Dr. Maumenee's insights, efforts, and leadership have contributed significantly to this remarkable scientific journey. In this manuscript, we present a short summary of the known LCA genes, LCA disease subtypes, and emerging treatment options. Our manuscript consolidates previous knowledge with current findings in an attempt to provide a more comprehensive understanding of LCA.
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Affiliation(s)
- Razek Georges Coussa
- a Department of Paediatric Surgery, Montreal Children's Hospital , McGill University Health Centre , Montreal , Quebec , Canada.,b The McGill Ocular Genetics Laboratory, Paediatric Ophthalmology Division , Montreal Children's Hospital, McGill University Health Centre , Montreal , Quebec , Canada
| | - Irma Lopez Solache
- b The McGill Ocular Genetics Laboratory, Paediatric Ophthalmology Division , Montreal Children's Hospital, McGill University Health Centre , Montreal , Quebec , Canada
| | - Robert K Koenekoop
- a Department of Paediatric Surgery, Montreal Children's Hospital , McGill University Health Centre , Montreal , Quebec , Canada.,b The McGill Ocular Genetics Laboratory, Paediatric Ophthalmology Division , Montreal Children's Hospital, McGill University Health Centre , Montreal , Quebec , Canada
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66
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Boye SE. Increased vulnerability of photoreceptors to aberrant splicing highlight the utility of AON-based therapy for CEP290-LCA. Stem Cell Investig 2017; 3:96. [PMID: 28078276 DOI: 10.21037/sci.2016.12.01] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 12/15/2016] [Indexed: 01/06/2023]
Affiliation(s)
- Shannon E Boye
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, FL, USA
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67
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McDougald DS, Kmiec E, Mills JA. Personalized models reveal mechanistic and therapeutic insights into CEP290-associated Leber congenital amaurosis. Stem Cell Investig 2016; 3:65. [PMID: 27868047 DOI: 10.21037/sci.2016.10.03] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 10/12/2016] [Indexed: 12/28/2022]
Affiliation(s)
- Devin S McDougald
- Center for Advanced Retinal and Ocular Therapeutics, F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Eric Kmiec
- Gene Editing Institute, Center for Translational Cancer Research, Helen F. Graham Cancer Center & Research Institute, Christiana Care Health System, Newark, DE 19702, USA
| | - Jason A Mills
- Center for Advanced Retinal and Ocular Therapeutics, F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
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68
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Parfitt DA, Lane A, Ramsden C, Jovanovic K, Coffey PJ, Hardcastle AJ, Cheetham ME. Using induced pluripotent stem cells to understand retinal ciliopathy disease mechanisms and develop therapies. Biochem Soc Trans 2016; 44:1245-1251. [PMID: 27911706 PMCID: PMC5238943 DOI: 10.1042/bst20160156] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Revised: 07/15/2016] [Accepted: 07/19/2016] [Indexed: 12/23/2022]
Abstract
The photoreceptor cells in the retina have a highly specialised sensory cilium, the outer segment (OS), which is important for detecting light. Mutations in cilia-related genes often result in retinal degeneration. The ability to reprogramme human cells into induced pluripotent stem cells and then differentiate them into a wide range of different cell types has revolutionised our ability to study human disease. To date, however, the challenge of producing fully differentiated photoreceptors in vitro has limited the application of this technology in studying retinal degeneration. In this review, we will discuss recent advances in stem cell technology and photoreceptor differentiation. In particular, the development of photoreceptors with rudimentary OS that can be used to understand disease mechanisms and as an important model to test potential new therapies for inherited retinal ciliopathies.
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Affiliation(s)
- David A. Parfitt
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Amelia Lane
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | - Conor Ramsden
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
| | | | - Peter J. Coffey
- UCL Institute of Ophthalmology, 11-43 Bath Street, London, EC1V 9EL UK
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69
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In vivo genome editing as a potential treatment strategy for inherited retinal dystrophies. Prog Retin Eye Res 2016; 56:1-18. [PMID: 27623223 DOI: 10.1016/j.preteyeres.2016.09.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Revised: 09/06/2016] [Accepted: 09/08/2016] [Indexed: 12/20/2022]
Abstract
In vivo genome editing represents an emerging field in the treatment of monogenic disorders, as it may constitute a solution to the current hurdles in classic gene addition therapy, which are the low levels and limited duration of transgene expression. Following the introduction of a double strand break (DSB) at the mutational site by highly specific endonucleases, such as TALENs (transcription activator like effector nucleases) or RNA based nucleases (clustered regulatory interspaced short palindromic repeats - CRISPR-Cas), the cell's own DNA repair machinery restores integrity to the DNA strand and corrects the mutant sequence, thus allowing the cell to produce protein levels as needed. The DNA repair happens either through the error prone non-homologous end-joining (NHEJ) pathway or with high fidelity through homology directed repair (HDR) in the presence of a DNA donor template. A third pathway called microhomology mediated endjoining (MMEJ) has been recently discovered. In this review, the authors focus on the different DNA repair mechanisms, the current state of the art tools for genome editing and the particularities of the retina and photoreceptors with regard to in vivo therapeutic approaches. Finally, current attempts in the field of retinal in vivo genome editing are discussed and future directions of research identified.
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70
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Wiley LA, Burnight ER, Drack AV, Banach BB, Ochoa D, Cranston CM, Madumba RA, East JS, Mullins RF, Stone EM, Tucker BA. Using Patient-Specific Induced Pluripotent Stem Cells and Wild-Type Mice to Develop a Gene Augmentation-Based Strategy to Treat CLN3-Associated Retinal Degeneration. Hum Gene Ther 2016; 27:835-846. [PMID: 27400765 DOI: 10.1089/hum.2016.049] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Juvenile neuronal ceroid lipofuscinosis (JNCL) is a childhood neurodegenerative disease with early-onset, severe central vision loss. Affected children develop seizures and CNS degeneration accompanied by severe motor and cognitive deficits. There is no cure for JNCL, and patients usually die during the second or third decade of life. In this study, independent lines of induced pluripotent stem cells (iPSCs) were generated from two patients with molecularly confirmed mutations in CLN3, the gene mutated in JNCL. Clinical-grade adeno-associated adenovirus serotype 2 (AAV2) carrying the full-length coding sequence of human CLN3 was generated in a U.S. Food and Drug Administration-registered cGMP facility. AAV2-CLN3 was efficacious in restoring full-length CLN3 transcript and protein in patient-specific fibroblasts and iPSC-derived retinal neurons. When injected into the subretinal space of wild-type mice, purified AAV2-CLN3 did not show any evidence of retinal toxicity. This study provides proof-of-principle for initiation of a clinical trial using AAV-mediated gene augmentation for the treatment of children with CLN3-associated retinal degeneration.
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Affiliation(s)
- Luke A Wiley
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Erin R Burnight
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Arlene V Drack
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Bailey B Banach
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Dalyz Ochoa
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Cathryn M Cranston
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Robert A Madumba
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Jade S East
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Robert F Mullins
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Edwin M Stone
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
| | - Budd A Tucker
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, Carver College of Medicine, University of Iowa , Iowa City, Iowa
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71
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Wiley LA, Beebe DC, Mullins RF, Stone EM, Tucker BA. A Method for Sectioning and Immunohistochemical Analysis of Stem Cell-Derived 3-D Organoids. ACTA ACUST UNITED AC 2016; 37:1C.19.1-1C.19.11. [PMID: 27171793 DOI: 10.1002/cpsc.3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
This unit describes a protocol for embedding, sectioning, and immunocytochemical analysis of pluripotent stem cell-derived 3-D organoids. Specifically, we describe a method to embed iPSC-derived retinal cups in low-melt agarose, acquire thick sections using a vibratome tissue slicer, and perform immunohistochemical analysis. This method includes an approach for antibody labeling that minimizes the amount of antibody needed for individual experiments and that utilizes large-volume washing to increase the signal-to-noise ratio, allowing for clean, high-resolution imaging of developing cell types. The universal methods described can be employed regardless of the type of pluripotent stem cell used and 3-D organoid generated. © 2016 by John Wiley & Sons, Inc.
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Affiliation(s)
- Luke A Wiley
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - David C Beebe
- Departments of Ophthalmology & Visual Sciences and Cell Biology and Physiology, Washington University School of Medicine, Washington University, St. Louis, Missouri
| | - Robert F Mullins
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Edwin M Stone
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Budd A Tucker
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa
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72
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Garanto A, Chung DC, Duijkers L, Corral-Serrano JC, Messchaert M, Xiao R, Bennett J, Vandenberghe LH, Collin RWJ. In vitro and in vivo rescue of aberrant splicing in CEP290-associated LCA by antisense oligonucleotide delivery. Hum Mol Genet 2016; 25:2552-2563. [PMID: 27106101 DOI: 10.1093/hmg/ddw118] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 04/08/2016] [Accepted: 04/12/2016] [Indexed: 12/29/2022] Open
Abstract
Leber congenital amaurosis (LCA) is a severe disorder resulting in visual impairment usually starting in the first year of life. The most frequent genetic cause of LCA is an intronic mutation in CEP290 (c.2991 + 1655A > G) that creates a cryptic splice donor site resulting in the insertion of a pseudoexon (exon X) into CEP290 mRNA. Previously, we showed that naked antisense oligonucleotides (AONs) effectively restored normal CEP290 splicing in patient-derived lymphoblastoid cells. We here explore the therapeutic potential of naked and adeno-associated virus (AAV)-packaged AONs in vitro and in vivo In both cases, AON delivery fully restored CEP290 pre-mRNA splicing, significantly increased CEP290 protein levels and rescued a ciliary phenotype present in patient-derived fibroblast cells. Moreover, administration of naked and AAV-packaged AONs to the retina of a humanized mutant Cep290 mouse model, carrying the intronic mutation, showed a statistically significant reduction of exon X-containing Cep290 transcripts, without compromising the retinal structure. Together, our data highlight the tremendous therapeutic prospective of AONs for the treatment of not only CEP290-associated LCA but potentially many other subtypes of retinal dystrophy caused by splicing mutations.
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Affiliation(s)
- Alejandro Garanto
- Department of Human Genetics.,Donders Center for NeurosciencesRadboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Daniel C Chung
- F.M. Kirby Center for Molecular Ophthalmology and Center for Advanced Retinal and Ophthalmic Therapeutics, Scheie Eye Institute, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | | | - Julio C Corral-Serrano
- Department of Human Genetics.,Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Muriël Messchaert
- Department of Human Genetics.,Donders Center for NeurosciencesRadboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Ru Xiao
- Grousbeck Gene Therapy Center, Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - Jean Bennett
- F.M. Kirby Center for Molecular Ophthalmology and Center for Advanced Retinal and Ophthalmic Therapeutics, Scheie Eye Institute, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Luk H Vandenberghe
- Grousbeck Gene Therapy Center, Department of Ophthalmology, Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA 02114, USA
| | - Rob W J Collin
- Department of Human Genetics .,Donders Center for NeurosciencesRadboud University Medical Center, 6525 GA Nijmegen, The Netherlands
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73
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Parfitt DA, Lane A, Ramsden CM, Carr AJF, Munro PM, Jovanovic K, Schwarz N, Kanuga N, Muthiah MN, Hull S, Gallo JM, da Cruz L, Moore AT, Hardcastle AJ, Coffey PJ, Cheetham ME. Identification and Correction of Mechanisms Underlying Inherited Blindness in Human iPSC-Derived Optic Cups. Cell Stem Cell 2016; 18:769-781. [PMID: 27151457 PMCID: PMC4899423 DOI: 10.1016/j.stem.2016.03.021] [Citation(s) in RCA: 235] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 02/08/2016] [Accepted: 03/29/2016] [Indexed: 12/14/2022]
Abstract
Leber congenital amaurosis (LCA) is an inherited retinal dystrophy that causes childhood blindness. Photoreceptors are especially sensitive to an intronic mutation in the cilia-related gene CEP290, which causes missplicing and premature termination, but the basis of this sensitivity is unclear. Here, we generated differentiated photoreceptors in three-dimensional optic cups and retinal pigment epithelium (RPE) from iPSCs with this common CEP290 mutation to investigate disease mechanisms and evaluate candidate therapies. iPSCs differentiated normally into RPE and optic cups, despite abnormal CEP290 splicing and cilia defects. The highest levels of aberrant splicing and cilia defects were observed in optic cups, explaining the retinal-specific manifestation of this CEP290 mutation. Treating optic cups with an antisense morpholino effectively blocked aberrant splicing and restored expression of full-length CEP290, restoring normal cilia-based protein trafficking. These results provide a mechanistic understanding of the retina-specific phenotypes in CEP290 LCA patients and potential strategies for therapeutic intervention. Generation of 3D optic cups with opsin-expressing photoreceptors and outer segments A CEP290-LCA intronic mutation creates a cryptic exon that impairs ciliogenesis Aberrant splicing is increased in photoreceptors compared to other cell types Antisense oligonucleotide can block the cryptic exon and restore CEP290 function
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Affiliation(s)
- David A Parfitt
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Amelia Lane
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Conor M Ramsden
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; Moorfields Eye Hospital, 162 City Road, London EC1V 2PD, UK
| | - Amanda-Jayne F Carr
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Peter M Munro
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Katarina Jovanovic
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Nele Schwarz
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Naheed Kanuga
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Manickam N Muthiah
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; Moorfields Eye Hospital, 162 City Road, London EC1V 2PD, UK
| | - Sarah Hull
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; Moorfields Eye Hospital, 162 City Road, London EC1V 2PD, UK
| | - Jean-Marc Gallo
- Maurice Wohl Clinical Neurosciences Institute, Institute of Psychiatry, Psychology, and Neuroscience, Kings College London, London SE5 9NU, UK
| | - Lyndon da Cruz
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; Moorfields Eye Hospital, 162 City Road, London EC1V 2PD, UK
| | - Anthony T Moore
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK; Moorfields Eye Hospital, 162 City Road, London EC1V 2PD, UK
| | - Alison J Hardcastle
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Peter J Coffey
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
| | - Michael E Cheetham
- Ocular Biology and Therapeutics, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK.
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74
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Di Foggia V, Makwana P, Ali RR, Sowden JC. Induced Pluripotent Stem Cell Therapies for Degenerative Disease of the Outer Retina: Disease Modeling and Cell Replacement. J Ocul Pharmacol Ther 2016; 32:240-52. [PMID: 27027805 DOI: 10.1089/jop.2015.0143] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Stem cell therapies are being explored as potential treatments for retinal disease. How to replace neurons in a degenerated retina presents a continued challenge for the regenerative medicine field that, if achieved, could restore sight. The major issues are: (i) the source and availability of donor cells for transplantation; (ii) the differentiation of stem cells into the required retinal cells; and (iii) the delivery, integration, functionality, and survival of new cells in the host neural network. This review considers the use of induced pluripotent stem cells (iPSC), currently under intense investigation, as a platform for cell transplantation therapy. Moreover, patient-specific iPSC are being developed for autologous cell transplantation and as a tool for modeling specific retinal diseases, testing gene therapies, and drug screening.
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Affiliation(s)
- Valentina Di Foggia
- 1 UCL Institute of Child Health, University College London , London, United Kingdom
| | - Priyanka Makwana
- 1 UCL Institute of Child Health, University College London , London, United Kingdom
| | - Robin R Ali
- 2 UCL Institute of Ophthalmology , London, United Kingdom
| | - Jane C Sowden
- 1 UCL Institute of Child Health, University College London , London, United Kingdom
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75
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Ohlemacher SK, Sridhar A, Xiao Y, Hochstetler AE, Sarfarazi M, Cummins TR, Meyer JS. Stepwise Differentiation of Retinal Ganglion Cells from Human Pluripotent Stem Cells Enables Analysis of Glaucomatous Neurodegeneration. Stem Cells 2016; 34:1553-62. [PMID: 26996528 DOI: 10.1002/stem.2356] [Citation(s) in RCA: 93] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 12/18/2015] [Accepted: 01/06/2016] [Indexed: 12/14/2022]
Abstract
Human pluripotent stem cells (hPSCs), including both embryonic and induced pluripotent stem cells, possess the unique ability to readily differentiate into any cell type of the body, including cells of the retina. Although previous studies have demonstrated the ability to differentiate hPSCs to a retinal lineage, the ability to derive retinal ganglion cells (RGCs) from hPSCs has been complicated by the lack of specific markers with which to identify these cells from a pluripotent source. In the current study, the definitive identification of hPSC-derived RGCs was accomplished by their directed, stepwise differentiation through an enriched retinal progenitor intermediary, with resultant RGCs expressing a full complement of associated features and proper functional characteristics. These results served as the basis for the establishment of induced pluripotent stem cells (iPSCs) from a patient with a genetically inherited form of glaucoma, which results in damage and loss of RGCs. Patient-derived RGCs specifically exhibited a dramatic increase in apoptosis, similar to the targeted loss of RGCs in glaucoma, which was significantly rescued by the addition of candidate neuroprotective factors. Thus, the current study serves to establish a method by which to definitively acquire and identify RGCs from hPSCs and demonstrates the ability of hPSCs to serve as an effective in vitro model of disease progression. Moreover, iPSC-derived RGCs can be utilized for future drug screening approaches to identify targets for the treatment of glaucoma and other optic neuropathies. Stem Cells 2016;34:1553-1562.
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Affiliation(s)
- Sarah K Ohlemacher
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA
| | - Akshayalakshmi Sridhar
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA
| | - Yucheng Xiao
- Stark Neurosciences Research Institute, Indiana University, Indianapolis, IN, USA
| | - Alexandra E Hochstetler
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA
| | - Mansoor Sarfarazi
- Molecular Ophthalmic Genetics Laboratory, University of Connecticut Health Center, Farmington, CT, USA
| | - Theodore R Cummins
- Stark Neurosciences Research Institute, Indiana University, Indianapolis, IN, USA.,Department of Pharmacology and Toxicology, Indiana University, Indianapolis, IN, USA
| | - Jason S Meyer
- Department of Biology, Indiana University Purdue University Indianapolis, Indianapolis, IN, USA.,Stark Neurosciences Research Institute, Indiana University, Indianapolis, IN, USA.,Department of Medical and Molecular Genetics, Indiana University, Indianapolis, IN, USA
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76
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Dalkara D, Goureau O, Marazova K, Sahel JA. Let There Be Light: Gene and Cell Therapy for Blindness. Hum Gene Ther 2016; 27:134-47. [PMID: 26751519 PMCID: PMC4779297 DOI: 10.1089/hum.2015.147] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 01/06/2016] [Indexed: 12/14/2022] Open
Abstract
Retinal degenerative diseases are a leading cause of irreversible blindness. Retinal cell death is the main cause of vision loss in genetic disorders such as retinitis pigmentosa, Stargardt disease, and Leber congenital amaurosis, as well as in complex age-related diseases such as age-related macular degeneration. For these blinding conditions, gene and cell therapy approaches offer therapeutic intervention at various disease stages. The present review outlines advances in therapies for retinal degenerative disease, focusing on the progress and challenges in the development and clinical translation of gene and cell therapies. A significant body of preclinical evidence and initial clinical results pave the way for further development of these cutting edge treatments for patients with retinal degenerative disorders.
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Affiliation(s)
- Deniz Dalkara
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de la Vision, France
| | - Olivier Goureau
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de la Vision, France
| | - Katia Marazova
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de la Vision, France
| | - José-Alain Sahel
- Sorbonne Universités, UPMC Université Paris 06, INSERM, CNRS, Institut de la Vision, France
- Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC 1423, France
- Fondation Ophtalmologique Adolphe de Rothschild, Paris, France
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77
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Maeder ML, Gersbach CA. Genome-editing Technologies for Gene and Cell Therapy. Mol Ther 2016; 24:430-46. [PMID: 26755333 PMCID: PMC4786923 DOI: 10.1038/mt.2016.10] [Citation(s) in RCA: 410] [Impact Index Per Article: 51.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 01/07/2016] [Indexed: 12/11/2022] Open
Abstract
Gene therapy has historically been defined as the addition of new genes to human cells. However, the recent advent of genome-editing technologies has enabled a new paradigm in which the sequence of the human genome can be precisely manipulated to achieve a therapeutic effect. This includes the correction of mutations that cause disease, the addition of therapeutic genes to specific sites in the genome, and the removal of deleterious genes or genome sequences. This review presents the mechanisms of different genome-editing strategies and describes each of the common nuclease-based platforms, including zinc finger nucleases, transcription activator-like effector nucleases (TALENs), meganucleases, and the CRISPR/Cas9 system. We then summarize the progress made in applying genome editing to various areas of gene and cell therapy, including antiviral strategies, immunotherapies, and the treatment of monogenic hereditary disorders. The current challenges and future prospects for genome editing as a transformative technology for gene and cell therapy are also discussed.
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Affiliation(s)
| | - Charles A Gersbach
- Department of Biomedical Engineering, Duke University, Durham, North Carolina, USA.,Center for Genomic and Computational Biology, Duke University, Durham, North Carolina, USA.,Department of Orthopaedic Surgery, Duke University Medical Center, Durham, North Carolina, USA
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78
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Induced Pluripotent Stem Cells and Outer Retinal Disease. Stem Cells Int 2016; 2016:2850873. [PMID: 26880948 PMCID: PMC4736410 DOI: 10.1155/2016/2850873] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 11/23/2015] [Accepted: 11/25/2015] [Indexed: 12/17/2022] Open
Abstract
The retina, which is composed of multiple layers of differing cell types, has been considered the first choice for gene therapy, disease modeling, and stem cell-derived retinal cell transplant therapy. Because of its special characteristics, the retina, located in the posterior part of the eye, can be well observed directly after gene therapy or transplantation. The blood-retinal barrier is part of a specialized ocular microenvironment that is immune privileged. This protects transplanted cells and tissue. Having two eyes makes perfect natural control possible after a single eye receives gene or stem cell therapy. For this reason, research about exploring retinal diseases' underlying molecular mechanisms and potential therapeutic approach using stem cell technique has been developing rapidly. This review is to present an up-to-date summary of the iPSC's sources, variations, differentiation methods, and the wide-ranging application of iPSCs-RPCS or iPSCs-RPE on retinal disease modeling, diagnostics, and therapeutics.
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79
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Chang B. Mouse Models as Tools to Identify Genetic Pathways for Retinal Degeneration, as Exemplified by Leber's Congenital Amaurosis. Methods Mol Biol 2016; 1438:417-430. [PMID: 27150101 DOI: 10.1007/978-1-4939-3661-8_21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Leber's congenital amaurosis (LCA) is an inherited retinal degenerative disease characterized by severe loss of vision in the first year of life. In addition to early vision loss, a variety of other eye-related abnormalities including roving eye movements, deep-set eyes, and sensitivity to bright light also occur with this disease. Many animal models of LCA are available and the study them has led to a better understanding of the pathology of the disease, and has led to the development of therapeutic strategies aimed at curing or slowing down LCA. Mouse models, with their well-developed genetics and similarity to human physiology and anatomy, serve as powerful tools with which to investigate the etiology of human LCA. Such mice provide reproducible, experimental systems for elucidating pathways of normal development, function, designing strategies and testing compounds for translational research and gene-based therapies aimed at delaying the diseases progression. In this chapter, I describe tools used in the discovery and evaluation of mouse models of LCA including a Phoenix Image-Guided Optical Coherence Tomography (OCT) and a Diagnosys Espion Visual Electrophysiology System. Three mouse models are described, the rd3 mouse model for LCA12 and LCA1, the rd12 mouse model for LCA2, and the rd16 mouse model for LCA10.
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Affiliation(s)
- Bo Chang
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME, 04609, USA.
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80
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Giacalone JC, Wiley LA, Burnight ER, Songstad AE, Mullins RF, Stone EM, Tucker BA. Concise Review: Patient-Specific Stem Cells to Interrogate Inherited Eye Disease. Stem Cells Transl Med 2015; 5:132-40. [PMID: 26683869 PMCID: PMC4729558 DOI: 10.5966/sctm.2015-0206] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 10/16/2015] [Indexed: 12/13/2022] Open
Abstract
Heritable diseases of the retina are major causes of blindness worldwide. The recent success of gene augmentation trials for the treatment of RPE65-associated Leber congenital amaurosis has underscored the need for model systems that accurately recapitulate disease. How induced pluripotent stem cell technology is being used to confirm the pathogenesis of novel genetic variants, interrogate the pathophysiology of disease, and accelerate the development of patient-centered treatments is discussed. Whether we are driving to work or spending time with loved ones, we depend on our sense of vision to interact with the world around us. Therefore, it is understandable why blindness for many is feared above death itself. Heritable diseases of the retina, such as glaucoma, age-related macular degeneration, and retinitis pigmentosa, are major causes of blindness worldwide. The recent success of gene augmentation trials for the treatment of RPE65-associated Leber congenital amaurosis has underscored the need for model systems that accurately recapitulate disease. With the advent of patient-specific induced pluripotent stem cells (iPSCs), researchers are now able to obtain disease-specific cell types that would otherwise be unavailable for molecular analysis. In the present review, we discuss how the iPSC technology is being used to confirm the pathogenesis of novel genetic variants, interrogate the pathophysiology of disease, and accelerate the development of patient-centered treatments. Significance Stem cell technology has created the opportunity to advance treatments for multiple forms of blindness. Researchers are now able to use a person’s cells to generate tissues found in the eye. This technology can be used to elucidate the genetic causes of disease and develop treatment strategies. In the present review, how stem cell technology is being used to interrogate the pathophysiology of eye disease and accelerate the development of patient-centered treatments is discussed.
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Affiliation(s)
- Joseph C Giacalone
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Luke A Wiley
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Erin R Burnight
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Allison E Songstad
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Robert F Mullins
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
| | - Edwin M Stone
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA Howard Hughes Medical Institute, University of Iowa, Iowa City, Iowa, USA
| | - Budd A Tucker
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Carver College of Medicine, University of Iowa, Iowa City, Iowa, USA
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81
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Tucker BA, Cranston CM, Anfinson KA, Shrestha S, Streb LM, Leon A, Mullins RF, Stone EM. Using patient-specific induced pluripotent stem cells to interrogate the pathogenicity of a novel retinal pigment epithelium-specific 65 kDa cryptic splice site mutation and confirm eligibility for enrollment into a clinical gene augmentation trial. Transl Res 2015; 166:740-749.e1. [PMID: 26364624 PMCID: PMC4702513 DOI: 10.1016/j.trsl.2015.08.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 08/18/2015] [Accepted: 08/24/2015] [Indexed: 01/07/2023]
Abstract
Retinal pigment epithelium-specific 65 kDa (RPE65)-associated Leber congenital amaurosis is an autosomal recessive disease that results in reduced visual acuity and night blindness beginning at birth. It is one of the few retinal degenerative disorders for which promising clinical gene transfer trials are currently underway. However, the ability to enroll patients in a gene augmentation trial is dependent on the identification of 2 bona fide disease-causing mutations, and there are some patients with the phenotype of RPE65-associated disease who might benefit from gene transfer but are ineligible because 2 disease-causing genetic variations have not yet been identified. Some such patients have novel mutations in RPE65 for which pathogenicity is difficult to confirm. The goal of this study was to determine if an intronic mutation identified in a 2-year-old patient with presumed RPE65-associated disease was truly pathogenic and grounds for inclusion in a clinical gene augmentation trial. Sequencing of the RPE65 gene revealed 2 mutations: (1) a previously identified disease-causing exonic leucine-to-proline mutation (L408P) and (2) a novel single point mutation in intron 3 (IVS3-11) resulting in an A>G change. RT-PCR analysis using RNA extracted from control human donor eye-derived primary RPE, control iPSC-RPE cells, and proband iPSC-RPE cells revealed that the identified IVS3-11 variation caused a splicing defect that resulted in a frameshift and insertion of a premature stop codon. In this study, we demonstrate how patient-specific iPSCs can be used to confirm pathogenicity of unknown mutations, which can enable positive clinical outcomes.
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Affiliation(s)
- Budd A Tucker
- Stephen A Wynn Institute for Vision Research, Department of Ophthalmology and Visual Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Cathryn M Cranston
- Stephen A Wynn Institute for Vision Research, Department of Ophthalmology and Visual Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Kristin A Anfinson
- Stephen A Wynn Institute for Vision Research, Department of Ophthalmology and Visual Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Suruchi Shrestha
- Stephen A Wynn Institute for Vision Research, Department of Ophthalmology and Visual Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Luan M Streb
- Stephen A Wynn Institute for Vision Research, Department of Ophthalmology and Visual Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Alejandro Leon
- Department of Ophthalmology, Children's Hospital New Orleans, New Orleans, La
| | - Robert F Mullins
- Stephen A Wynn Institute for Vision Research, Department of Ophthalmology and Visual Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa
| | - Edwin M Stone
- Stephen A Wynn Institute for Vision Research, Department of Ophthalmology and Visual Science, Carver College of Medicine, University of Iowa, Iowa City, Iowa; Howard Hughes Medical Institute, Department of Ophthalmology and Visual Science, University of Iowa, Iowa City, Iowa.
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82
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Small KW, DeLuca AP, Whitmore SS, Rosenberg T, Silva-Garcia R, Udar N, Puech B, Garcia CA, Rice TA, Fishman GA, Héon E, Folk JC, Streb LM, Haas CM, Wiley LA, Scheetz TE, Fingert JH, Mullins RF, Tucker BA, Stone EM. North Carolina Macular Dystrophy Is Caused by Dysregulation of the Retinal Transcription Factor PRDM13. Ophthalmology 2015; 123:9-18. [PMID: 26507665 DOI: 10.1016/j.ophtha.2015.10.006] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 10/07/2015] [Accepted: 10/07/2015] [Indexed: 12/30/2022] Open
Abstract
PURPOSE To identify specific mutations causing North Carolina macular dystrophy (NCMD). DESIGN Whole-genome sequencing coupled with reverse transcription polymerase chain reaction (RT-PCR) analysis of gene expression in human retinal cells. PARTICIPANTS A total of 141 members of 12 families with NCMD and 261 unrelated control individuals. METHODS Genome sequencing was performed on 8 affected individuals from 3 families affected with chromosome 6-linked NCMD (MCDR1) and 2 individuals affected with chromosome 5-linked NCMD (MCDR3). Variants observed in the MCDR1 locus with frequencies <1% in published databases were confirmed using Sanger sequencing. Confirmed variants absent from all published databases were sought in 8 additional MCDR1 families and 261 controls. The RT-PCR analysis of selected genes was performed in stem cell-derived human retinal cells. MAIN OUTCOME MEASURES Co-segregation of rare genetic variants with disease phenotype. RESULTS Five sequenced individuals with MCDR1-linked NCMD shared a haplotype of 14 rare variants spanning 1 Mb of the disease-causing allele. One of these variants (V1) was absent from all published databases and all 261 controls, but was found in 5 additional NCMD kindreds. This variant lies in a DNase 1 hypersensitivity site (DHS) upstream of both the PRDM13 and CCNC genes. Sanger sequencing of 1 kb centered on V1 was performed in the remaining 4 NCMD probands, and 2 additional novel single nucleotide variants (V2 in 3 families and V3 in 1 family) were identified in the DHS within 134 bp of the location of V1. A complete duplication of the PRDM13 gene was also discovered in a single family (V4). The RT-PCR analysis of PRDM13 expression in developing retinal cells revealed marked developmental regulation. Next-generation sequencing of 2 individuals with MCDR3-linked NCMD revealed a 900-kb duplication that included the entire IRX1 gene (V5). The 5 mutations V1 to V5 segregated perfectly in the 102 affected and 39 unaffected members of the 12 NCMD families. CONCLUSIONS We identified 5 rare mutations, each capable of arresting human macular development. Four of these strongly implicate the involvement of PRDM13 in macular development, whereas the pathophysiologic mechanism of the fifth remains unknown but may involve the developmental dysregulation of IRX1.
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Affiliation(s)
- Kent W Small
- Molecular Insight Research Foundation, Glendale, California
| | - Adam P DeLuca
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, Iowa
| | - S Scott Whitmore
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, Iowa
| | - Thomas Rosenberg
- National Eye Clinic, Kennedy Center, Glostrup, Denmark, and Institute of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
| | | | - Nitin Udar
- Molecular Insight Research Foundation, Glendale, California
| | - Bernard Puech
- Service d'Exploration de la vision et Neuro-ophtalmologie CHRU, Lille, France
| | - Charles A Garcia
- University of Texas Health Science Center at Houston, Houston, Texas
| | - Thomas A Rice
- Byers Eye Institute, Stanford University School of Medicine, Palo Alto, California
| | - Gerald A Fishman
- The Pangere Center for Inherited Retinal Diseases, The Chicago Lighthouse for People Who Are Blind or Visually Impaired, Chicago, Illinois
| | - Elise Héon
- Department of Ophthalmology and Vision Sciences, Programme of Genetics and Genomic Medicine, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - James C Folk
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, Iowa
| | - Luan M Streb
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, Iowa
| | - Christine M Haas
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, Iowa
| | - Luke A Wiley
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, Iowa
| | - Todd E Scheetz
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, Iowa
| | - John H Fingert
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, Iowa
| | - Robert F Mullins
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, Iowa
| | - Budd A Tucker
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, Iowa
| | - Edwin M Stone
- Department of Ophthalmology and Visual Sciences, Stephen A. Wynn Institute for Vision Research, University of Iowa, Iowa City, Iowa.
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83
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DeLuca AP, Whitmore SS, Barnes J, Sharma TP, Westfall TA, Scott CA, Weed MC, Wiley JS, Wiley LA, Johnston RM, Schnieders MJ, Lentz SR, Tucker BA, Mullins RF, Scheetz TE, Stone EM, Slusarski DC. Hypomorphic mutations in TRNT1 cause retinitis pigmentosa with erythrocytic microcytosis. Hum Mol Genet 2015; 25:44-56. [PMID: 26494905 DOI: 10.1093/hmg/ddv446] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Accepted: 10/19/2015] [Indexed: 02/07/2023] Open
Abstract
Retinitis pigmentosa (RP) is a highly heterogeneous group of disorders characterized by degeneration of the retinal photoreceptor cells and progressive loss of vision. While hundreds of mutations in more than 100 genes have been reported to cause RP, discovering the causative mutations in many patients remains a significant challenge. Exome sequencing in an individual affected with non-syndromic RP revealed two plausibly disease-causing variants in TRNT1, a gene encoding a nucleotidyltransferase critical for tRNA processing. A total of 727 additional unrelated individuals with molecularly uncharacterized RP were completely screened for TRNT1 coding sequence variants, and a second family was identified with two members who exhibited a phenotype that was remarkably similar to the index patient. Inactivating mutations in TRNT1 have been previously shown to cause a severe congenital syndrome of sideroblastic anemia, B-cell immunodeficiency, recurrent fevers and developmental delay (SIFD). Complete blood counts of all three of our patients revealed red blood cell microcytosis and anisocytosis with only mild anemia. Characterization of TRNT1 in patient-derived cell lines revealed reduced but detectable TRNT1 protein, consistent with partial function. Suppression of trnt1 expression in zebrafish recapitulated several features of the human SIFD syndrome, including anemia and sensory organ defects. When levels of trnt1 were titrated, visual dysfunction was found in the absence of other phenotypes. The visual defects in the trnt1-knockdown zebrafish were ameliorated by the addition of exogenous human TRNT1 RNA. Our findings indicate that hypomorphic TRNT1 mutations can cause a recessive disease that is almost entirely limited to the retina.
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Affiliation(s)
- Adam P DeLuca
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences
| | - S Scott Whitmore
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences
| | | | - Tasneem P Sharma
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences
| | | | | | - Matthew C Weed
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences
| | - Jill S Wiley
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences
| | - Luke A Wiley
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences
| | - Rebecca M Johnston
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences
| | - Michael J Schnieders
- The Stephen A. Wynn Institute for Vision Research, Department of Biomedical Engineering, Department of Biochemistry, and
| | - Steven R Lentz
- Department of Internal Medicine; The University of Iowa, Iowa City, IA, USA
| | - Budd A Tucker
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences
| | - Robert F Mullins
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences
| | - Todd E Scheetz
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, Department of Biomedical Engineering
| | - Edwin M Stone
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences
| | - Diane C Slusarski
- The Stephen A. Wynn Institute for Vision Research, Department of Biology,
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84
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Qin Y, Gao WQ. Concise Review: Patient-Derived Stem Cell Research for Monogenic Disorders. Stem Cells 2015; 34:44-54. [DOI: 10.1002/stem.2112] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 06/05/2015] [Accepted: 06/20/2015] [Indexed: 12/24/2022]
Affiliation(s)
- Yiren Qin
- State Key Laboratory of Oncogenes and Related Genes, Renji-Med-X Clinical Stem Cell Research Center, Ren Ji Hospital, School of Medicine; hanghai Jiao Tong University; Shanghai People's Republic of China
| | - Wei-Qiang Gao
- State Key Laboratory of Oncogenes and Related Genes, Renji-Med-X Clinical Stem Cell Research Center, Ren Ji Hospital, School of Medicine; hanghai Jiao Tong University; Shanghai People's Republic of China
- School of Biomedical Engineering & Med-X Research Institute; Shanghai Jiao Tong University; Shanghai People's Republic of China
- Collaborative Innovation Center of Systems Biomedicine; Shanghai Jiao Tong University; Shanghai People's Republic of China
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85
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Starks RD, Beyer AM, Guo DF, Boland L, Zhang Q, Sheffield VC, Rahmouni K. Regulation of Insulin Receptor Trafficking by Bardet Biedl Syndrome Proteins. PLoS Genet 2015; 11:e1005311. [PMID: 26103456 PMCID: PMC4478011 DOI: 10.1371/journal.pgen.1005311] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 05/29/2015] [Indexed: 01/06/2023] Open
Abstract
Insulin and its receptor are critical for the regulation of metabolic functions, but the mechanisms underlying insulin receptor (IR) trafficking to the plasma membrane are not well understood. Here, we show that Bardet Biedl Syndrome (BBS) proteins are necessary for IR localization to the cell surface. We demonstrate that the IR interacts physically with BBS proteins, and reducing the expression of BBS proteins perturbs IR expression in the cell surface. We show the consequence of disrupting BBS proteins for whole body insulin action and glucose metabolism using mice lacking different BBS genes. These findings demonstrate the importance of BBS proteins in underlying IR cell surface expression. Our data identify defects in trafficking and localization of the IR as a novel mechanism accounting for the insulin resistance commonly associated with human BBS. This is supported by the reduced surface expression of the IR in fibroblasts derived from patients bearing the M390R mutation in the BBS1 gene. A main function of the hormone insulin in the body is to regulate metabolism of glucose. The hormone causes body cells in different organs and tissues to utilize glucose from the bloodstream, storing the excess amount. Insulin resistance which reflects the inability of insulin to properly regulate glucose metabolism is common in people with obesity and/or type 2 diabetes. This insulin resistance is strongly associated with cardiovascular disease and increases the risk of death. However, the reasons that account for this insulin resistance phenomenon are currently not well understood. Here, we show that Bardet Biedl Syndrome proteins are required for proper action of insulin. We found that cells or animals that are deficient in Bardet Biedl Syndrome proteins are unable to respond to insulin. These results provide an explanation why patients that carry mutations in the Bardet Biedl Syndrome genes are insulin resistant, and will potentially contribute to understand common human forms of insulin resistance.
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Affiliation(s)
- Rachel D. Starks
- Department of Pharmacology, University of Iowa College of Medicine, Iowa City, Iowa, United States of America
| | - Andreas M. Beyer
- Department of Internal Medicine, University of Iowa College of Medicine, Iowa City, Iowa, United States of America
| | - Deng Fu Guo
- Department of Pharmacology, University of Iowa College of Medicine, Iowa City, Iowa, United States of America
| | - Lauren Boland
- Department of Pharmacology, University of Iowa College of Medicine, Iowa City, Iowa, United States of America
| | - Qihong Zhang
- Department of Pediatrics, University of Iowa College of Medicine, Iowa City, Iowa, United States of America
- Howard Hughes Medical Institute, University of Iowa College of Medicine, Iowa City, Iowa, United States of America
| | - Val C. Sheffield
- Department of Pediatrics, University of Iowa College of Medicine, Iowa City, Iowa, United States of America
- Howard Hughes Medical Institute, University of Iowa College of Medicine, Iowa City, Iowa, United States of America
- * E-mail: (VCS); (KR)
| | - Kamal Rahmouni
- Department of Pharmacology, University of Iowa College of Medicine, Iowa City, Iowa, United States of America
- Department of Internal Medicine, University of Iowa College of Medicine, Iowa City, Iowa, United States of America
- FOE Diabetes Research Center, University of Iowa College of Medicine, Iowa City, Iowa, United States of America
- * E-mail: (VCS); (KR)
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86
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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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87
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Nash BM, Wright DC, Grigg JR, Bennetts B, Jamieson RV. Retinal dystrophies, genomic applications in diagnosis and prospects for therapy. Transl Pediatr 2015; 4:139-63. [PMID: 26835369 PMCID: PMC4729094 DOI: 10.3978/j.issn.2224-4336.2015.04.03] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Retinal dystrophies (RDs) are degenerative diseases of the retina which have marked clinical and genetic heterogeneity. Common presentations among these disorders include night or colour blindness, tunnel vision and subsequent progression to complete blindness. The known causative disease genes have a variety of developmental and functional roles with mutations in more than 120 genes shown to be responsible for the phenotypes. In addition, mutations within the same gene have been shown to cause different disease phenotypes, even amongst affected individuals within the same family highlighting further levels of complexity. The known disease genes encode proteins involved in retinal cellular structures, phototransduction, the visual cycle, and photoreceptor structure or gene regulation. This review aims to demonstrate the high degree of genetic complexity in both the causative disease genes and their associated phenotypes, highlighting the more common clinical manifestation of retinitis pigmentosa (RP). The review also provides insight to recent advances in genomic molecular diagnosis and gene and cell-based therapies for the RDs.
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Affiliation(s)
- Benjamin M Nash
- 1 Eye Genetics Research Group, Children's Medical Research Institute, University of Sydney, The Children's Hospital at Westmead and Save Sight Institute, Sydney, NSW, Australia ; 2 Sydney Genome Diagnostics, The Children's Hospital at Westmead, Sydney, NSW, Australia ; 3 Discipline of Paediatrics and Child Health, Sydney Medical School, University of Sydney, NSW, Australia
| | - Dale C Wright
- 1 Eye Genetics Research Group, Children's Medical Research Institute, University of Sydney, The Children's Hospital at Westmead and Save Sight Institute, Sydney, NSW, Australia ; 2 Sydney Genome Diagnostics, The Children's Hospital at Westmead, Sydney, NSW, Australia ; 3 Discipline of Paediatrics and Child Health, Sydney Medical School, University of Sydney, NSW, Australia
| | - John R Grigg
- 1 Eye Genetics Research Group, Children's Medical Research Institute, University of Sydney, The Children's Hospital at Westmead and Save Sight Institute, Sydney, NSW, Australia ; 2 Sydney Genome Diagnostics, The Children's Hospital at Westmead, Sydney, NSW, Australia ; 3 Discipline of Paediatrics and Child Health, Sydney Medical School, University of Sydney, NSW, Australia
| | - Bruce Bennetts
- 1 Eye Genetics Research Group, Children's Medical Research Institute, University of Sydney, The Children's Hospital at Westmead and Save Sight Institute, Sydney, NSW, Australia ; 2 Sydney Genome Diagnostics, The Children's Hospital at Westmead, Sydney, NSW, Australia ; 3 Discipline of Paediatrics and Child Health, Sydney Medical School, University of Sydney, NSW, Australia
| | - Robyn V Jamieson
- 1 Eye Genetics Research Group, Children's Medical Research Institute, University of Sydney, The Children's Hospital at Westmead and Save Sight Institute, Sydney, NSW, Australia ; 2 Sydney Genome Diagnostics, The Children's Hospital at Westmead, Sydney, NSW, Australia ; 3 Discipline of Paediatrics and Child Health, Sydney Medical School, University of Sydney, NSW, Australia
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88
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Cho SK, Dang C, Wang X, Ragan R, Kwon YJ. Mixing-sequence-dependent nucleic acid complexation and gene transfer efficiency by polyethylenimine. Biomater Sci 2015. [PMID: 26221945 DOI: 10.1039/c5bm00041f] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Polyplexes, complexed nucleic acids by cationic polymers, are the most common forms of nonviral gene delivery vectors. In contrast to a great deal of efforts in synthesizing novel cationic polymers and exploring their extracellular and intracellular delivery pathways, polyplex preparation methods of mixing nucleic acids and cationic polymers are often overlooked. In this study, the mixing sequence, that is adding nucleic acids to polymers or vice versa, was found to greatly affect complexation of both plasmid DNA and siRNA, polyplexes' size, and polyplexes' surface charge, which all collaboratively affected the transfection efficiency and cytotoxicity. Adding polyethylenimine (PEI), the most conventionally used standard in nonviral gene delivery, to plasmid DNA and siRNA resulted in larger polyplexes, higher gene expression and silencing, but higher cytotoxicity than polyplexes prepared in the reverse order. Based on the experimental results, the authors developed a model that gradual addition of cationic polymers (e.g., PEI) to nucleic acids (e.g., plasmid DNA and siRNA) incorporates more copies of nucleic acids in larger polyplexes in a smaller number, results in higher gene expression and silencing levels in transfected cells, and generates higher cytotoxicity by leaving more free polymers upon complete mixing than the other mixing sequence. The proposed model can be explored using a broad range of cationic polymers and nucleic acids, and provide insightful information about how to prepare polyplexed nonviral vectors for efficient and safe gene delivery.
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Affiliation(s)
- S K Cho
- Department of Chemistry, Dong-A University, Busan, South Korea
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89
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Chacon-Camacho OF, Zenteno JC. Review and update on the molecular basis of Leber congenital amaurosis. World J Clin Cases 2015; 3:112-124. [PMID: 25685757 PMCID: PMC4317604 DOI: 10.12998/wjcc.v3.i2.112] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Revised: 10/03/2014] [Accepted: 11/19/2014] [Indexed: 02/05/2023] Open
Abstract
Inherited retinal diseases are uncommon pathologies and one of the most harmful causes of childhood and adult blindness. Leber congenital amaurosis (LCA) is the most severe kind of these diseases accounting for approximately 5% of the whole retinal dystrophies and 20% of the children that study on blind schools. Clinical ophthalmologic findings including severe vision loss, nystagmus and ERG abnormalities should be suspected through the first year of life in this group of patients. Phenotypic variability is found when LCA patients have a full ophthalmologic examination. However, a correct diagnosis may be carried out; the determination of ophthalmologic clues as light sensibility, night blindness, fundus pigmentation, among other, join with electroretinographics findings, optical coherence tomography, and new technologies as molecular gene testing may help to reach to a precise diagnosis. Several retinal clinical features in LCA may suggest a genetic or gene particular defect; thus genetic-molecular tools could directly corroborate the clinical diagnosis. Currently, approximately 20 genes have been associated to LCA. In this review, historical perspective, clinical ophthalmological findings, new molecular-genetics technologies, possible phenotype-genotypes correlations, and gene therapy for some LCA genes are described.
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90
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Zheng A, Li Y, Tsang SH. Personalized therapeutic strategies for patients with retinitis pigmentosa. Expert Opin Biol Ther 2015; 15:391-402. [PMID: 25613576 DOI: 10.1517/14712598.2015.1006192] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
INTRODUCTION Retinitis pigmentosa (RP) encompasses many different hereditary retinal degenerations that are caused by a vast array of different gene mutations and have highly variable disease presentations and severities. This heterogeneity poses a significant therapeutic challenge, although an answer may eventually be found through two recent innovations: induced pluripotent stem cells (iPSCs) and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas genome editing. AREAS COVERED This review discusses the wide-ranging applications of iPSCs and CRISPR-including disease modelling, diagnostics and therapeutics - with an ultimate view towards understanding how these two technologies can come together to address disease heterogeneity and orphan genes in a novel personalized medicine platform. An extensive literature search was conducted in PubMed and Google Scholar, with a particular focus on high-impact research published within the last 1 - 2 years and centered broadly on the subjects of retinal gene therapy, iPSC-derived outer retina cells, stem cell transplantation and CRISPR/Cas gene editing. EXPERT OPINION For the retinal pigment epithelium, autologous transplantation of gene-corrected grafts derived from iPSCs may well be technically feasible in the near future. Photoreceptor transplantation faces more significant unresolved technical challenges but remains an achievable, if more distant, goal given the rapid pace of advancements in the field.
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Affiliation(s)
- Andrew Zheng
- Columbia University, College of Physicians and Surgeons , 50 Haven Ave, Box #123, Bard Hall, New York, NY 10032 , USA
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91
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Treatment of ocular disorders by gene therapy. Eur J Pharm Biopharm 2014; 95:331-42. [PMID: 25536112 DOI: 10.1016/j.ejpb.2014.12.022] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Revised: 12/08/2014] [Accepted: 12/15/2014] [Indexed: 12/27/2022]
Abstract
Gene therapy to treat ocular disorders is still starting, and current therapies are primarily experimental, with most human clinical trials still in research state, although beginning to show encouraging results. Currently 33 clinical trials have been approved, are in progress, or have been completed. The most promising results have been obtained in clinical trials of ocular gene therapy for Leber Congenital Amaurosis, which have prompted the study of several ocular diseases that are good candidates to be treated with gene therapy: glaucoma, age-related macular degeneration, retinitis pigmentosa, or choroideremia. The success of gene therapy relies on the efficient delivery of the genetic material to target cells, achieving optimum long-term gene expression. Although viral vectors have been widely used, their potential risk associated mainly with immunogenicity and mutagenesis has promoted the design of non-viral vectors. In this review, the main administration routes and the most studied delivery systems, viral and non-viral, for ocular gene therapy are presented. The primary ocular disease candidates to be treated with gene therapy have been also reviewed, including the genetic basis and the most relevant preclinical and clinical studies.
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92
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iPS Cells for Modelling and Treatment of Retinal Diseases. J Clin Med 2014; 3:1511-41. [PMID: 26237613 PMCID: PMC4470196 DOI: 10.3390/jcm3041511] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 11/16/2014] [Accepted: 11/18/2014] [Indexed: 01/10/2023] Open
Abstract
For many decades, we have relied on immortalised retinal cell lines, histology of enucleated human eyes, animal models, clinical observation, genetic studies and human clinical trials to learn more about the pathogenesis of retinal diseases and explore treatment options. The recent availability of patient-specific induced pluripotent stem cells (iPSC) for deriving retinal lineages has added a powerful alternative tool for discovering new disease-causing mutations, studying genotype-phenotype relationships, performing therapeutics-toxicity screening and developing personalised cell therapy. This review article provides a clinical perspective on the current and potential benefits of iPSC for managing the most common blinding diseases of the eye: inherited retinal diseases and age-related macular degeneration.
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93
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Mysore N, Koenekoop J, Li S, Ren H, Keser V, Lopez-Solache I, Koenekoop RK. A Review of Secondary Photoreceptor Degenerations in Systemic Disease. Cold Spring Harb Perspect Med 2014; 5:cshperspect.a025825. [PMID: 25475108 DOI: 10.1101/cshperspect.a025825] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Photoreceptor neuronal degenerations are common and incurable causes of human blindness with one in 2000 affected. Approximately, half of all patients are associated with known mutations in more than 200 disease genes. Most retinal degenerations are restricted to the retina (primary retinal degeneration) but photoreceptor degeneration can also be found in a wide variety of systemic and syndromic diseases. These are called secondary retinal degenerations. We review several well-known systemic diseases with retinal degenerations (RD). We discuss RD with hearing loss, RD with brain disease, and RD with musculoskeletal disease. We then postulate which retinal degenerations may also have previously undetected systemic features. Emerging new and exciting evidence is showing that ubiquitously expressed genes associated with multitissue syndromic disorders may also harbor mutations that cause isolated primary retinal degeneration. Examples are RPGR, CEP290, CLN3, MFSD5, and HK1 mutations that cause a wide variety of primary retinal degenerations with intact systems.
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Affiliation(s)
- Naveen Mysore
- Department of Paediatric Surgery, Human Genetics and Ophthalmology, McGill University, Montreal, Quebec H3A 1A1, Canada McGill Ocular Genetics Laboratory, Montreal, Quebec H3H 1P3, Canada
| | - Jamie Koenekoop
- McGill Ocular Genetics Laboratory, Montreal, Quebec H3H 1P3, Canada
| | - Shen Li
- McGill Ocular Genetics Laboratory, Montreal, Quebec H3H 1P3, Canada
| | - Huanan Ren
- McGill Ocular Genetics Laboratory, Montreal, Quebec H3H 1P3, Canada
| | - Vafa Keser
- McGill Ocular Genetics Laboratory, Montreal, Quebec H3H 1P3, Canada
| | | | - Robert K Koenekoop
- Department of Paediatric Surgery, Human Genetics and Ophthalmology, McGill University, Montreal, Quebec H3A 1A1, Canada McGill Ocular Genetics Laboratory, Montreal, Quebec H3H 1P3, Canada Faculty of Medicine, Human Genetics, McGill University, Montreal, Quebec H3A 1B1, Canada Montreal Children's Hospital Research Institute, Montreal, Quebec H3H 1P3, Canada
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94
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Burnight ER, Wiley LA, Mullins RF, Stone EM, Tucker BA. Gene therapy using stem cells. Cold Spring Harb Perspect Med 2014; 5:cshperspect.a017434. [PMID: 25395375 DOI: 10.1101/cshperspect.a017434] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Viral-mediated gene augmentation therapy has recently shown success in restoring vision to patients with retinal degenerative disorders. Key to this success was the availability of animal models that accurately presented the human phenotype to test preclinical efficacy and safety. These exciting studies support the use of gene therapy in the treatment of devastating retinal degenerative diseases. In some cases, however, in vivo gene therapy for retinal degeneration would not be effective because the cell types targeted are no longer present. The development of somatic cell reprogramming methods provides an attractive source of autologous cells for transplantation and treatment of retinal degenerative disease. This article explores the development of gene therapy and patient-derived stem cells for the purpose of restoring vision to individuals suffering from inherited retinal degenerations.
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Affiliation(s)
- Erin R Burnight
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa 52242
| | - Luke A Wiley
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa 52242
| | - Robert F Mullins
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa 52242
| | - Edwin M Stone
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa 52242 Howard Hughes Medical Institute, University of Iowa, Iowa City, Iowa 52242
| | - Budd A Tucker
- The Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, Iowa 52242
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95
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Wiley LA, Burnight ER, Songstad AE, Drack AV, Mullins RF, Stone EM, Tucker BA. Patient-specific induced pluripotent stem cells (iPSCs) for the study and treatment of retinal degenerative diseases. Prog Retin Eye Res 2014; 44:15-35. [PMID: 25448922 DOI: 10.1016/j.preteyeres.2014.10.002] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Revised: 10/15/2014] [Accepted: 10/16/2014] [Indexed: 12/26/2022]
Abstract
Vision is the sense that we use to navigate the world around us. Thus it is not surprising that blindness is one of people's most feared maladies. Heritable diseases of the retina, such as age-related macular degeneration and retinitis pigmentosa, are the leading cause of blindness in the developed world, collectively affecting as many as one-third of all people over the age of 75, to some degree. For decades, scientists have dreamed of preventing vision loss or of restoring the vision of patients affected with retinal degeneration through drug therapy, gene augmentation or a cell-based transplantation approach. In this review we will discuss the use of the induced pluripotent stem cell technology to model and develop various treatment modalities for the treatment of inherited retinal degenerative disease. We will focus on the use of iPSCs for interrogation of disease pathophysiology, analysis of drug and gene therapeutics and as a source of autologous cells for cell transplantation and replacement.
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Affiliation(s)
- Luke A Wiley
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
| | - Erin R Burnight
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
| | - Allison E Songstad
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
| | - Arlene V Drack
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
| | - Robert F Mullins
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA
| | - Edwin M Stone
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA; Howard Hughes Medical Institute, University of Iowa, Iowa City, IA, USA
| | - Budd A Tucker
- Stephen A. Wynn Institute for Vision Research, Department of Ophthalmology and Visual Sciences, University of Iowa, Iowa City, IA, USA.
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