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Du W, Li J, Tang X, Yu W, Zhao M. CRISPR/SaCas9-based gene editing rescues photoreceptor degeneration throughout a rhodopsin-associated autosomal dominant retinitis pigmentosa mouse model. Exp Biol Med (Maywood) 2023; 248:1818-1828. [PMID: 37837380 PMCID: PMC10792415 DOI: 10.1177/15353702231199069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 08/12/2023] [Indexed: 10/16/2023] Open
Abstract
Rhodopsin (Rho) gene mutation was considered the highest prevalent mutation in autosomal dominant retinitis pigmentosa (ADRP); however, effective therapeutics for ADRP have not been developed. The process of gene editing via the clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 system offers the potentiality to provide cures for dominantly inherited disorders. Herein, we generated a CRISPR/SaCas9-mediated gene reduction system to inactivate the Rho mutant, while replacing normal rhodopsin in a rhodopsin mutation mouse model. When Rho-P23H knock-in mice were administered a subretinal injection of the "reduction and replacement" system, the expression of mutant rhodopsin was reduced, and retinal function was improved. Therefore, we concluded that CRISPR/SaCas9-based "reduction and replacement" gene therapy could provide structural and functional benefits for Rho mutant ADRP, as well as new directions for future clinical research on the treatment of such gain-of-function genetic diseases.
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Affiliation(s)
- Wei Du
- Department of Ophthalmology and Clinical Centre of Optometry, Peking University People’s Hospital, Beijing 100044, China
- Eye Diseases and Optometry Institute, Peking University People’s Hospital, Beijing 100044, China
- Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, Beijing 100044, China
- College of Optometry, Peking University Health Science Center, Beijing 100044, China
| | - Jiarui Li
- Department of Ophthalmology and Clinical Centre of Optometry, Peking University People’s Hospital, Beijing 100044, China
- Eye Diseases and Optometry Institute, Peking University People’s Hospital, Beijing 100044, China
- Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, Beijing 100044, China
- College of Optometry, Peking University Health Science Center, Beijing 100044, China
| | - Xin Tang
- Department of Ophthalmology and Clinical Centre of Optometry, Peking University People’s Hospital, Beijing 100044, China
- Eye Diseases and Optometry Institute, Peking University People’s Hospital, Beijing 100044, China
- Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, Beijing 100044, China
- College of Optometry, Peking University Health Science Center, Beijing 100044, China
| | - Wenzhen Yu
- Department of Ophthalmology and Clinical Centre of Optometry, Peking University People’s Hospital, Beijing 100044, China
- Eye Diseases and Optometry Institute, Peking University People’s Hospital, Beijing 100044, China
- Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, Beijing 100044, China
- College of Optometry, Peking University Health Science Center, Beijing 100044, China
| | - Mingwei Zhao
- Department of Ophthalmology and Clinical Centre of Optometry, Peking University People’s Hospital, Beijing 100044, China
- Eye Diseases and Optometry Institute, Peking University People’s Hospital, Beijing 100044, China
- Beijing Key Laboratory of Diagnosis and Therapy of Retinal and Choroid Diseases, Beijing 100044, China
- College of Optometry, Peking University Health Science Center, Beijing 100044, China
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Becherucci V, Bacci GM, Marziali E, Sodi A, Bambi F, Caputo R. The New Era of Therapeutic Strategies for the Treatment of Retinitis Pigmentosa: A Narrative Review of Pathomolecular Mechanisms for the Development of Cell-Based Therapies. Biomedicines 2023; 11:2656. [PMID: 37893030 PMCID: PMC10604477 DOI: 10.3390/biomedicines11102656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 09/20/2023] [Accepted: 09/25/2023] [Indexed: 10/29/2023] Open
Abstract
Retinitis pigmentosa, defined more properly as cone-rod dystrophy, is a paradigm of inherited diffuse retinal dystrophies, one of the rare diseases with the highest prevalence in the worldwide population and one of the main causes of low vision in the pediatric and elderly age groups. Advancements in and the understanding of molecular biology and gene-editing technologies have raised interest in laying the foundation for new therapeutic strategies for rare diseases. As a consequence, new possibilities for clinicians and patients are arising due to the feasibility of treating such a devastating disorder, reducing its complications. The scope of this review focuses on the pathomolecular mechanisms underlying RP better to understand the prospects of its treatment using innovative approaches.
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Affiliation(s)
- Valentina Becherucci
- Cell Factory Meyer, Children’s Hospital A. Meyer Istituti di Ricovero e Cura a Carattere Scientifico (IRCCS), University of Florence, 50139 Florence, Italy; (V.B.); (F.B.)
| | - Giacomo Maria Bacci
- Pediatric Ophthalmology Unit, Children’s Hospital A. Meyer Istituti di Ricovero e Cura a Carattere Scientifico (IRCCS), University of Florence, 50139 Florence, Italy; (E.M.); (R.C.)
| | - Elisa Marziali
- Pediatric Ophthalmology Unit, Children’s Hospital A. Meyer Istituti di Ricovero e Cura a Carattere Scientifico (IRCCS), University of Florence, 50139 Florence, Italy; (E.M.); (R.C.)
| | - Andrea Sodi
- Department of Neuroscience, Psychology, Drug Research and Child Health, University of Florence, 50139 Florence, Italy;
| | - Franco Bambi
- Cell Factory Meyer, Children’s Hospital A. Meyer Istituti di Ricovero e Cura a Carattere Scientifico (IRCCS), University of Florence, 50139 Florence, Italy; (V.B.); (F.B.)
| | - Roberto Caputo
- Pediatric Ophthalmology Unit, Children’s Hospital A. Meyer Istituti di Ricovero e Cura a Carattere Scientifico (IRCCS), University of Florence, 50139 Florence, Italy; (E.M.); (R.C.)
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Sp S, Mitra RN, Zheng M, Chrispell JD, Wang K, Kwon YS, Weiss ER, Han Z. Gene augmentation for autosomal dominant retinitis pigmentosa using rhodopsin genomic loci nanoparticles in the P23H +/- knock-in murine model. Gene Ther 2023; 30:628-640. [PMID: 36935427 DOI: 10.1038/s41434-023-00394-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 02/13/2023] [Accepted: 02/28/2023] [Indexed: 03/21/2023]
Abstract
Gene therapy for autosomal dominant retinitis pigmentosa (adRP) is challenged by the dominant inheritance of the mutant genes, which would seemingly require a combination of mutant suppression and wild-type replacement of the appropriate gene. We explore the possibility that delivery of a nanoparticle (NP)-mediated full-length mouse genomic rhodopsin (gRho) or human genomic rhodopsin (gRHO) locus can overcome the dominant negative effects of the mutant rhodopsin in the clinically relevant P23H+/--knock-in heterozygous mouse model. Our results demonstrate that mice in both gRho and gRHO NP-treated groups exhibit significant structural and functional recovery of the rod photoreceptors, which lasted for 3 months post-injection, indicating a promising reduction in photoreceptor degeneration. We performed miRNA transcriptome analysis using next generation sequencing and detected differentially expressed miRNAs as a first step towards identifying miRNAs that could potentially be used as rhodopsin gene expression enhancers or suppressors for sustained photoreceptor rescue. Our results indicate that delivering an intact genomic locus as a transgene has a greater chance of success compared to the use of the cDNA for treatment of this model of adRP, emphasizing the importance of gene augmentation using a gDNA that includes regulatory elements.
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Affiliation(s)
- Simna Sp
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Rajendra N Mitra
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Min Zheng
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Jared D Chrispell
- Department of Cell Biology and Physiology, the University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Kai Wang
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Yong-Su Kwon
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Ellen R Weiss
- Department of Cell Biology and Physiology, the University of North Carolina, Chapel Hill, NC, 27599, USA
| | - Zongchao Han
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
- Carolina Institute for NanoMedicine, the University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
- Division of Pharmacoengineering & Molecular Pharmaceutics, Eshelman School of Pharmacy, the University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA.
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Li C, Peng C, Zhang C, Li N. Thicknesses of the retina and choroid in children with retinitis pigmentosa. BMC Ophthalmol 2023; 23:25. [PMID: 36650468 PMCID: PMC9843954 DOI: 10.1186/s12886-023-02772-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 01/04/2023] [Indexed: 01/19/2023] Open
Abstract
PURPOSE To compare the retinal thicknesses (RT) and choroidal thicknesses (CT) in retinitis pigmentosa (RP) children with those of healthy children using enhanced depth imaging (EDI) optical coherence tomography (OCT). The RT and CT in different genetic subgroups of autosomal dominant RP (ADRP) and X-linked inheritance RP (XLRP) were further studied to investigate the characteristics of retinal and choroidal changes in the early stages of RP. METHOD A retrospective analysis was performed on a group of patients with RP who underwent EDI-OCT. Thirty-two children (64 eyes) with RP and 28 age- and refraction-matched healthy children (56 eyes) were included in the study. Seven of the 32 RP children (14 eyes) had X-linked inheritance RP, and 10 (20 eyes) had autosomal dominant inheritance RP. RT and CT were measured by optical coherence tomography and compared between the 32 children with RP and 28 controls and between 7 XLRP and 10 ADRP children. RESULT Among the 32 children with RP, there were 18 males and 14 females with an average age of 6.6 ± 2.4 years. The mean RT was smaller in the RP group than in the control group at all of the locations. The mean temporal CT was smaller in the RP group (243.76 ± 60.82 μm) than in the control group (275.23 ± 40.92 μm) (P = 0.001), while there was no significant thinning on the foveal or nasal side. The best-corrected visual acuity of the XLRP group (0.40 ± 0.19) was worse than that of the ADRP group (0.68 ± 0.21) (P = 0.001), but the disease duration was the same (P = 0.685). The mean foveal RT was smaller in the XLRP group (173.85 ± 22.87 μm) than in the ADRP group (192.20 ± 9.70 μm) (P = 0.003), while there was no significant thinning at the other locations we studied. The mean temporal CT was smaller in the XLRP group (211.21 ± 69.41 μm) than in the ADRP group (274.45 ± 57.91 μm) (P = 0.007); CT measurements in XLRP children showed a more severe reduction on the temporal side. CONCLUSION The choroid in RP children was preferentially smaller on the temporal side of the macula, and retinal thinning was relatively extensive. Children with RP have strong clinical and genetic heterogeneity. The XLRP children demonstrated greater RT reduction at the fovea and greater CT reduction at the temporal side of the macula than the ADRP children. Our findings also provide evidence that the changes in thicknesses may be indicative of the greater severity of XLRP versus ADRP in the early stage.
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Affiliation(s)
- Cheng Li
- grid.411609.b0000 0004 1758 4735Department of Ophthalmology, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, No.56 Nanlishi Road, Xicheng District, Beijing, 100045 China
| | - Chunxia Peng
- grid.411609.b0000 0004 1758 4735Department of Ophthalmology, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, No.56 Nanlishi Road, Xicheng District, Beijing, 100045 China
| | - Chengyue Zhang
- grid.411609.b0000 0004 1758 4735Department of Ophthalmology, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, No.56 Nanlishi Road, Xicheng District, Beijing, 100045 China
| | - Ningdong Li
- grid.411609.b0000 0004 1758 4735Department of Ophthalmology, Beijing Children’s Hospital, Capital Medical University, National Center for Children’s Health, No.56 Nanlishi Road, Xicheng District, Beijing, 100045 China
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Chien Y, Hsiao YJ, Chou SJ, Lin TY, Yarmishyn AA, Lai WY, Lee MS, Lin YY, Lin TW, Hwang DK, Lin TC, Chiou SH, Chen SJ, Yang YP. Nanoparticles-mediated CRISPR-Cas9 gene therapy in inherited retinal diseases: applications, challenges, and emerging opportunities. J Nanobiotechnology 2022; 20:511. [DOI: 10.1186/s12951-022-01717-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 09/23/2022] [Indexed: 12/04/2022] Open
Abstract
AbstractInherited Retinal Diseases (IRDs) are considered one of the leading causes of blindness worldwide. However, the majority of them still lack a safe and effective treatment due to their complexity and genetic heterogeneity. Recently, gene therapy is gaining importance as an efficient strategy to address IRDs which were previously considered incurable. The development of the clustered regularly-interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) system has strongly empowered the field of gene therapy. However, successful gene modifications rely on the efficient delivery of CRISPR-Cas9 components into the complex three-dimensional (3D) architecture of the human retinal tissue. Intriguing findings in the field of nanoparticles (NPs) meet all the criteria required for CRISPR-Cas9 delivery and have made a great contribution toward its therapeutic applications. In addition, exploiting induced pluripotent stem cell (iPSC) technology and in vitro 3D retinal organoids paved the way for prospective clinical trials of the CRISPR-Cas9 system in treating IRDs. This review highlights important advances in NP-based gene therapy, the CRISPR-Cas9 system, and iPSC-derived retinal organoids with a focus on IRDs. Collectively, these studies establish a multidisciplinary approach by integrating nanomedicine and stem cell technologies and demonstrate the utility of retina organoids in developing effective therapies for IRDs.
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Panikker P, Roy S, Ghosh A, Poornachandra B, Ghosh A. Advancing precision medicines for ocular disorders: Diagnostic genomics to tailored therapies. Front Med (Lausanne) 2022; 9:906482. [PMID: 35911417 PMCID: PMC9334564 DOI: 10.3389/fmed.2022.906482] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 06/29/2022] [Indexed: 11/20/2022] Open
Abstract
Successful sequencing of the human genome and evolving functional knowledge of gene products has taken genomic medicine to the forefront, soon combining broadly with traditional diagnostics, therapeutics, and prognostics in patients. Recent years have witnessed an extraordinary leap in our understanding of ocular diseases and their respective genetic underpinnings. As we are entering the age of genomic medicine, rapid advances in genome sequencing, gene delivery, genome surgery, and computational genomics enable an ever-increasing capacity to provide a precise and robust diagnosis of diseases and the development of targeted treatment strategies. Inherited retinal diseases are a major source of blindness around the world where a large number of causative genes have been identified, paving the way for personalized diagnostics in the clinic. Developments in functional genetics and gene transfer techniques has also led to the first FDA approval of gene therapy for LCA, a childhood blindness. Many such retinal diseases are the focus of various clinical trials, making clinical diagnoses of retinal diseases, their underlying genetics and the studies of natural history important. Here, we review methodologies for identifying new genes and variants associated with various ocular disorders and the complexities associated with them. Thereafter we discuss briefly, various retinal diseases and the application of genomic technologies in their diagnosis. We also discuss the strategies, challenges, and potential of gene therapy for the treatment of inherited and acquired retinal diseases. Additionally, we discuss the translational aspects of gene therapy, the important vector types and considerations for human trials that may help advance personalized therapeutics in ophthalmology. Retinal disease research has led the application of precision diagnostics and precision therapies; therefore, this review provides a general understanding of the current status of precision medicine in ophthalmology.
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Affiliation(s)
| | - Shomereeta Roy
- Grow Research Laboratory, Narayana Nethralaya Foundation, Bengaluru, India
| | - Anuprita Ghosh
- Grow Research Laboratory, Narayana Nethralaya Foundation, Bengaluru, India
| | | | - Arkasubhra Ghosh
- Grow Research Laboratory, Narayana Nethralaya Foundation, Bengaluru, India
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Caruso SM, Quinn PM, da Costa BL, Tsang SH. CRISPR/Cas therapeutic strategies for autosomal dominant disorders. J Clin Invest 2022; 132:158287. [PMID: 35499084 PMCID: PMC9057583 DOI: 10.1172/jci158287] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Affiliation(s)
- Salvatore Marco Caruso
- Department of Biomedical Engineering and
- Jonas Children’s Vision Care and Bernard and Shirlee Brown Glaucoma Laboratory, Columbia University, New York, New York, USA
- Edward S. Harkness Eye Institute, NewYork-Presbyterian Hospital, New York, New York, USA
| | - Peter M.J. Quinn
- Jonas Children’s Vision Care and Bernard and Shirlee Brown Glaucoma Laboratory, Columbia University, New York, New York, USA
- Edward S. Harkness Eye Institute, NewYork-Presbyterian Hospital, New York, New York, USA
| | - Bruna Lopes da Costa
- Department of Biomedical Engineering and
- Jonas Children’s Vision Care and Bernard and Shirlee Brown Glaucoma Laboratory, Columbia University, New York, New York, USA
- Edward S. Harkness Eye Institute, NewYork-Presbyterian Hospital, New York, New York, USA
| | - Stephen H. Tsang
- Department of Biomedical Engineering and
- Jonas Children’s Vision Care and Bernard and Shirlee Brown Glaucoma Laboratory, Columbia University, New York, New York, USA
- Edward S. Harkness Eye Institute, NewYork-Presbyterian Hospital, New York, New York, USA
- Institute of Human Nutrition, Department of Ophthalmology and Department of Pathology and Cell Biology
- Columbia Stem Cell Initiative, and
- Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
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Shughoury A, Ciulla TA, Bakall B, Pennesi ME, Kiss S, Cunningham ET. Genes and Gene Therapy in Inherited Retinal Disease. Int Ophthalmol Clin 2021; 61:3-45. [PMID: 34584043 DOI: 10.1097/iio.0000000000000377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Mirtron-mediated RNA knockdown/replacement therapy for the treatment of dominant retinitis pigmentosa. Nat Commun 2021; 12:4934. [PMID: 34400638 PMCID: PMC8368061 DOI: 10.1038/s41467-021-25204-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 07/26/2021] [Indexed: 02/07/2023] Open
Abstract
Rhodopsin (RHO) gene mutations are a common cause of autosomal dominant retinitis pigmentosa (ADRP). The need to suppress toxic protein expression together with mutational heterogeneity pose challenges for treatment development. Mirtrons are atypical RNA interference effectors that are spliced from transcripts as short introns. Here, we develop a novel mirtron-based knockdown/replacement gene therapy for the mutation-independent treatment of RHO-related ADRP, and demonstrate efficacy in a relevant mammalian model. Splicing and potency of rhodopsin-targeting candidate mirtrons are initially determined, and a mirtron-resistant codon-modified version of the rhodopsin coding sequence is validated in vitro. These elements are then combined within a single adeno-associated virus (AAV) and delivered subretinally in a RhoP23H knock-in mouse model of ADRP. This results in significant mouse-to-human rhodopsin RNA replacement and is associated with a slowing of retinal degeneration. This provides proof of principle that synthetic mirtrons delivered by AAV are capable of reducing disease severity in vivo.
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Botto C, Rucli M, Tekinsoy MD, Pulman J, Sahel JA, Dalkara D. Early and late stage gene therapy interventions for inherited retinal degenerations. Prog Retin Eye Res 2021; 86:100975. [PMID: 34058340 DOI: 10.1016/j.preteyeres.2021.100975] [Citation(s) in RCA: 74] [Impact Index Per Article: 24.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 05/18/2021] [Accepted: 05/21/2021] [Indexed: 12/12/2022]
Abstract
Inherited and age-related retinal degeneration is the hallmark of a large group of heterogeneous diseases and is the main cause of untreatable blindness today. Genetic factors play a major pathogenic role in retinal degenerations for both monogenic diseases (such as retinitis pigmentosa) and complex diseases with established genetic risk factors (such as age-related macular degeneration). Progress in genotyping techniques and back of the eye imaging are completing our understanding of these diseases and their manifestations in patient populations suffering from retinal degenerations. It is clear that whatever the genetic cause, the majority of vision loss in retinal diseases results from the loss of photoreceptor function. The timing and circumstances surrounding the loss of photoreceptor function determine the adequate therapeutic approach to use for each patient. Among such approaches, gene therapy is rapidly becoming a therapeutic reality applicable in the clinic. This massive move from laboratory work towards clinical application has been propelled by the advances in our understanding of disease genetics and mechanisms, gene delivery vectors, gene editing systems, and compensatory strategies for loss of photoreceptor function. Here, we provide an overview of existing modalities of retinal gene therapy and their relevance based on the needs of patient populations suffering from inherited retinal degenerations.
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Affiliation(s)
- Catherine Botto
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France
| | - Marco Rucli
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France
| | - Müge Defne Tekinsoy
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France
| | - Juliette Pulman
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France
| | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France; Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, United States; CHNO des Quinze-Vingts, INSERM-DGOS CIC 1423, F-75012, Paris, France; Fondation Ophtalmologique Rothschild, F-75019, Paris, France
| | - Deniz Dalkara
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012, Paris, France.
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Chiu W, Lin TY, Chang YC, Isahwan-Ahmad Mulyadi Lai H, Lin SC, Ma C, Yarmishyn AA, Lin SC, Chang KJ, Chou YB, Hsu CC, Lin TC, Chen SJ, Chien Y, Yang YP, Hwang DK. An Update on Gene Therapy for Inherited Retinal Dystrophy: Experience in Leber Congenital Amaurosis Clinical Trials. Int J Mol Sci 2021; 22:ijms22094534. [PMID: 33926102 PMCID: PMC8123696 DOI: 10.3390/ijms22094534] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/22/2021] [Accepted: 04/22/2021] [Indexed: 12/20/2022] Open
Abstract
Inherited retinal dystrophies (IRDs) are a group of rare eye diseases caused by gene mutations that result in the degradation of cone and rod photoreceptors or the retinal pigment epithelium. Retinal degradation progress is often irreversible, with clinical manifestations including color or night blindness, peripheral visual defects and subsequent vision loss. Thus, gene therapies that restore functional retinal proteins by either replenishing unmutated genes or truncating mutated genes are needed. Coincidentally, the eye’s accessibility and immune-privileged status along with major advances in gene identification and gene delivery systems heralded gene therapies for IRDs. Among these clinical trials, voretigene neparvovec-rzyl (Luxturna), an adeno-associated virus vector-based gene therapy drug, was approved by the FDA for treating patients with confirmed biallelic RPE65 mutation-associated Leber Congenital Amaurosis (LCA) in 2017. This review includes current IRD gene therapy clinical trials and further summarizes preclinical studies and therapeutic strategies for LCA, including adeno-associated virus-based gene augmentation therapy, 11-cis-retinal replacement, RNA-based antisense oligonucleotide therapy and CRISPR-Cas9 gene-editing therapy. Understanding the gene therapy development for LCA may accelerate and predict the potential hurdles of future therapeutics translation. It may also serve as the template for the research and development of treatment for other IRDs.
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Affiliation(s)
- Wei Chiu
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan; (W.C.); (S.-C.L.); (S.-C.L.); (K.-J.C.); (Y.-B.C.); (C.-C.H.)
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
| | - Ting-Yi Lin
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
- School of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Yun-Chia Chang
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei 11217, Taiwan;
| | - Henkie Isahwan-Ahmad Mulyadi Lai
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
- Institute of Pharmacology, College of Medicine, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan
| | - Shen-Che Lin
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan; (W.C.); (S.-C.L.); (S.-C.L.); (K.-J.C.); (Y.-B.C.); (C.-C.H.)
| | - Chun Ma
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
- Department of Medicine, National Taiwan University, Taipei 10617, Taiwan
| | - Aliaksandr A. Yarmishyn
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
| | - Shiuan-Chen Lin
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan; (W.C.); (S.-C.L.); (S.-C.L.); (K.-J.C.); (Y.-B.C.); (C.-C.H.)
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
| | - Kao-Jung Chang
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan; (W.C.); (S.-C.L.); (S.-C.L.); (K.-J.C.); (Y.-B.C.); (C.-C.H.)
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan
| | - Yu-Bai Chou
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan; (W.C.); (S.-C.L.); (S.-C.L.); (K.-J.C.); (Y.-B.C.); (C.-C.H.)
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei 11217, Taiwan;
| | - Chih-Chien Hsu
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan; (W.C.); (S.-C.L.); (S.-C.L.); (K.-J.C.); (Y.-B.C.); (C.-C.H.)
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei 11217, Taiwan;
| | - Tai-Chi Lin
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei 11217, Taiwan;
| | - Shih-Jen Chen
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei 11217, Taiwan;
| | - Yueh Chien
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
- Division of Basic Research, Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
- Correspondence: (Y.C.); (Y.-P.Y.); (D.-K.H.)
| | - Yi-Ping Yang
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
- Division of Basic Research, Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
- Institute of Food Safety and Health Risk Assessment, National Yang Ming Chiao Tung University, Taipei 11221, Taiwan
- Correspondence: (Y.C.); (Y.-P.Y.); (D.-K.H.)
| | - De-Kuang Hwang
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan; (T.-Y.L.); (H.I.-A.M.L.); (C.M.); (A.A.Y.); (T.-C.L.); (S.-J.C.)
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei 11217, Taiwan;
- Correspondence: (Y.C.); (Y.-P.Y.); (D.-K.H.)
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12
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Singh RK, Binette F, Seiler M, Petersen-Jones SM, Nasonkin IO. Pluripotent Stem Cell-Based Organoid Technologies for Developing Next-Generation Vision Restoration Therapies of Blindness. J Ocul Pharmacol Ther 2021; 37:147-156. [PMID: 33052761 PMCID: PMC8060716 DOI: 10.1089/jop.2020.0016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 07/28/2020] [Indexed: 12/25/2022] Open
Abstract
Blindness, associated with death of retinal cells at the back of the eye, is caused by a number of conditions with high prevalence such as glaucoma, age-related macular degeneration, and diabetic retinopathy. In addition, a large number of orphan inherited (mostly monogenic) conditions, such as retinitis pigmentosa and Leber Congenital Amaurosis, add to the overall number of patients with blinding retinal degenerative diseases. Blindness caused by deterioration and loss of retina is so far incurable. Modern biomedical research leveraging molecular and regenerative medicine approaches had a number of groundbreaking discoveries and proof-of-principle treatments of blindness in animals. However, these methods are slow to be standardized and commercialized as therapies to benefit people losing their eyesight due to retinal degenerative conditions. In this review, we will outline major regenerative medicine approaches, which are emerging as promising for preserving or/and restoring vision. We discuss the potential of each of these approaches to reach commercialization step and be converted to treatments, which could at least ameliorate blindness caused by retinal cell death.
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Affiliation(s)
| | | | - Magdalene Seiler
- Stem Cell Research Center, University of California, Irvine, Irvine, California, USA
- Department of Physical Medicine & Rehabilitation, University of California, Irvine, Irvine, California, USA
- Department of Ophthalmology, University of California, Irvine, Irvine, California, USA
- Department of Anatomy & Neurobiology, University of California, Irvine, Irvine, California, USA
| | - Simon M. Petersen-Jones
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, Michigan, USA
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13
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Patrizi C, Llado M, Benati D, Iodice C, Marrocco E, Guarascio R, Surace EM, Cheetham ME, Auricchio A, Recchia A. Allele-specific editing ameliorates dominant retinitis pigmentosa in a transgenic mouse model. Am J Hum Genet 2021; 108:295-308. [PMID: 33508235 PMCID: PMC7896132 DOI: 10.1016/j.ajhg.2021.01.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 01/08/2021] [Indexed: 12/11/2022] Open
Abstract
Retinitis pigmentosa (RP) is a group of progressive retinal degenerations of mostly monogenic inheritance, which cause blindness in about 1:3,500 individuals worldwide. Heterozygous variants in the rhodopsin (RHO) gene are the most common cause of autosomal dominant RP (adRP). Among these, missense variants at C-terminal proline 347, such as p.Pro347Ser, cause severe adRP recurrently in European affected individuals. Here, for the first time, we use CRISPR/Cas9 to selectively target the p.Pro347Ser variant while preserving the wild-type RHO allele in vitro and in a mouse model of adRP. Detailed in vitro, genomic, and biochemical characterization of the rhodopsin C-terminal editing demonstrates a safe downregulation of p.Pro347Ser expression leading to partial recovery of photoreceptor function in a transgenic mouse model treated with adeno-associated viral vectors. This study supports the safety and efficacy of CRISPR/Cas9-mediated allele-specific editing and paves the way for a permanent and precise correction of heterozygous variants in dominantly inherited retinal diseases.
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Affiliation(s)
- Clarissa Patrizi
- Centre for Regenerative Medicine, Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Manel Llado
- Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Italy
| | - Daniela Benati
- Centre for Regenerative Medicine, Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Carolina Iodice
- Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Italy
| | - Elena Marrocco
- Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Italy
| | | | - Enrico M Surace
- Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Italy; Medical Genetics, Department of Translational Medicine, Federico II University, 80125 Naples, Italy
| | | | - Alberto Auricchio
- Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Italy; Medical Genetics, Department of Advanced Biomedicine, Federico II University, 80125 Naples, Italy.
| | - Alessandra Recchia
- Centre for Regenerative Medicine, Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy.
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14
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Zhang CJ, Ma Y, Jin ZB. The road to restore vision with photoreceptor regeneration. Exp Eye Res 2020; 202:108283. [PMID: 33010290 DOI: 10.1016/j.exer.2020.108283] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 09/13/2020] [Accepted: 09/24/2020] [Indexed: 12/12/2022]
Abstract
Neuroretinal diseases are the predominant cause of irreversible blindness worldwide, mainly due to photoreceptor loss. Currently, there are no radical treatments to fully reverse the degeneration or even stop the disease progression. Thus, it is urgent to develop new biological therapeutics for these diseases on the clinical side. Stem cell-based treatments have become a promising therapeutic for neuroretinal diseases through the replacement of damaged cells with photoreceptors and some allied cells. To date, considerable efforts have been made to regenerate the diseased retina based on stem cell technology. In this review, we overview the current status of stem cell-based treatments for photoreceptor regeneration, including the major cell sources derived from different stem cells in pre-clinical or clinical trial stages. Additionally, we discuss herein the major challenges ahead for and potential new strategy toward photoreceptor regeneration.
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Affiliation(s)
- Chang-Jun Zhang
- Laboratory for Stem Cell & Retinal Regeneration, The Eye Hospital, Wenzhou Medical University, Wenzhou, 325027, China
| | - Ya Ma
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Science Key Laboratory, Beijing, 100730, China
| | - Zi-Bing Jin
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Science Key Laboratory, Beijing, 100730, China.
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15
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Palfi A, Yesmambetov A, Millington-Ward S, Shortall C, Humphries P, Kenna PF, Chadderton N, Farrar GJ. AAV-Delivered Tulp1 Supplementation Therapy Targeting Photoreceptors Provides Minimal Benefit in Tulp1-/- Retinas. Front Neurosci 2020; 14:891. [PMID: 32973439 PMCID: PMC7482550 DOI: 10.3389/fnins.2020.00891] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 07/30/2020] [Indexed: 12/23/2022] Open
Abstract
With marketing approval of the first ocular gene therapy, and other gene therapies in clinical trial, treatments for inherited retinal degenerations (IRDs) have become a reality. Biallelic mutations in the tubby like protein 1 gene (TULP1) are causative of IRDs in humans; a mouse knock-out model (Tulp1−/−) is characterized by a similar disease phenotype. We developed a Tulp1 supplementation therapy for Tulp1−/− mice. Utilizing subretinal AAV2/5 delivery at postnatal day (p)2–3 and rhodopsin-kinase promoter (GRK1P) we targeted Tulp1 to photoreceptor cells exploring three doses, 2.2E9, 3.7E8, and 1.2E8 vgs. Tulp1 mRNA and TULP1 protein were assessed by RT-qPCR, western blot and immunocytochemistry, and visual function by electroretinography. Our results indicate that TULP1 was expressed in photoreceptors; achieved levels of Tulp1 mRNA and protein were similar to wild type levels at p20. However, the thickness of the outer nuclear layer (ONL) did not improve in treated Tulp1−/− mice. There was a small and transient electroretinography benefit in the treated retinas at 4 weeks of age (not observed by 6 weeks) when using 3.7E8 vg dose. Dark-adapted mixed rod and cone a- and b-wave amplitudes were 24.3 ± 13.5 μV and 52.2 ± 31.7 μV in treated Tulp1−/− mice, which were significantly different (p < 0.001, t-test), from those detected in untreated eyes (7.1 ± 7.0 μV and 9.4 ± 15.1 μV, respectively). Our results indicate that Tulp1 supplementation in photoreceptors may not be sufficient to provide robust benefit in Tulp1−/− mice. As such, further studies are required to fine tune the Tulp1 supplementation therapy, which, in principle, should rescue the Tulp1−/− phenotype.
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Affiliation(s)
- Arpad Palfi
- Department of Genetics, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
| | - Adlet Yesmambetov
- Department of Genetics, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
| | - Sophia Millington-Ward
- Department of Genetics, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
| | - Ciara Shortall
- Department of Genetics, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
| | - Pete Humphries
- Department of Genetics, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
| | - Paul F Kenna
- Department of Genetics, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
| | - Naomi Chadderton
- Department of Genetics, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
| | - G Jane Farrar
- Department of Genetics, School of Genetics and Microbiology, Trinity College Dublin, Dublin, Ireland
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16
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Orlans HO, Barnard AR, Patrício MI, McClements ME, MacLaren RE. Effect of AAV-Mediated Rhodopsin Gene Augmentation on Retinal Degeneration Caused by the Dominant P23H Rhodopsin Mutation in a Knock-In Murine Model. Hum Gene Ther 2020; 31:730-742. [DOI: 10.1089/hum.2020.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Harry O. Orlans
- Nuffield Laboratory of Ophthalmology, John Radcliffe Hospital, Oxford, United Kingdom
- Moorfields Eye Hospital, London, United Kingdom
| | - Alun R. Barnard
- Nuffield Laboratory of Ophthalmology, John Radcliffe Hospital, Oxford, United Kingdom
| | - Maria I. Patrício
- Nuffield Laboratory of Ophthalmology, John Radcliffe Hospital, Oxford, United Kingdom
| | | | - Robert E. MacLaren
- Nuffield Laboratory of Ophthalmology, John Radcliffe Hospital, Oxford, United Kingdom
- Moorfields Eye Hospital, London, United Kingdom
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17
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Ji C, Li Y, Kittredge A, Hopiavuori A, Ward N, Yao P, Fukuda Y, Zhang Y, Tsang SH, Yang T. Investigation and Restoration of BEST1 Activity in Patient-derived RPEs with Dominant Mutations. Sci Rep 2019; 9:19026. [PMID: 31836750 PMCID: PMC6910965 DOI: 10.1038/s41598-019-54892-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Accepted: 11/19/2019] [Indexed: 12/24/2022] Open
Abstract
BEST1 is a Ca2+-activated Cl- channel predominantly expressed in retinal pigment epithelium (RPE), and over 250 genetic mutations in the BEST1 gene have been identified to cause retinal degenerative disorders generally known as bestrophinopathies. As most BEST1 mutations are autosomal dominant, it is of great biomedical interest to determine their disease-causing mechanisms and the therapeutic potential of gene therapy. Here, we characterized six Best vitelliform macular dystrophy (BVMD)-associated BEST1 dominant mutations by documenting the patients' phenotypes, examining the subcellular localization of endogenous BEST1 and surface Ca2+-dependent Cl- currents in patient-derived RPEs, and analyzing the functional influences of these mutations on BEST1 in HEK293 cells. We found that all six mutations are loss-of-function with different levels and types of deficiencies, and further demonstrated the restoration of Ca2+-dependent Cl- currents in patient-derived RPE cells by WT BEST1 gene supplementation. Importantly, BEST1 dominant and recessive mutations are both rescuable at a similar efficacy by gene augmentation via adeno-associated virus (AAV), providing a proof-of-concept for curing the vast majority of bestrophinopathies.
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Affiliation(s)
- Changyi Ji
- Department of Pharmacology and Physiology, University of Rochester, School of Medicine and Dentistry, Rochester, NY, 14642, USA
| | - Yao Li
- Department of Ophthalmology, Columbia University, New York, NY, 10032, USA
| | - Alec Kittredge
- Department of Pharmacology and Physiology, University of Rochester, School of Medicine and Dentistry, Rochester, NY, 14642, USA
| | - Austin Hopiavuori
- Department of Pharmacology and Physiology, University of Rochester, School of Medicine and Dentistry, Rochester, NY, 14642, USA
| | - Nancy Ward
- Department of Pharmacology and Physiology, University of Rochester, School of Medicine and Dentistry, Rochester, NY, 14642, USA
| | - Peng Yao
- Aab Cardiovascular Research Institute, Department of Medicine, University of Rochester, School of Medicine & Dentistry, Rochester, NY, 14586, USA
| | - Yohta Fukuda
- Division of Advance Pharmaco-Science, Graduate School of Pharmaceutical Science, Osaka University, Yamadaoka 1-6, Suita, Osaka, 565-0871, Japan
| | - Yu Zhang
- Department of Pharmacology and Physiology, University of Rochester, School of Medicine and Dentistry, Rochester, NY, 14642, USA.
- Department of Ophthalmology, Columbia University, New York, NY, 10032, USA.
| | - Stephen H Tsang
- Jonas Children's Vision Care, and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology and Pathology & Cell Biology, Edward S. Harkness Eye Institute, Columbia Stem Cell Initiative, New York Presbyterian Hospital/Columbia University, New York, NY, 10032, USA.
| | - Tingting Yang
- Department of Pharmacology and Physiology, University of Rochester, School of Medicine and Dentistry, Rochester, NY, 14642, USA.
- Department of Ophthalmology, Columbia University, New York, NY, 10032, USA.
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18
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Vázquez-Domínguez I, Garanto A, Collin RWJ. Molecular Therapies for Inherited Retinal Diseases-Current Standing, Opportunities and Challenges. Genes (Basel) 2019; 10:genes10090654. [PMID: 31466352 PMCID: PMC6770110 DOI: 10.3390/genes10090654] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/23/2019] [Accepted: 08/26/2019] [Indexed: 12/15/2022] Open
Abstract
Inherited retinal diseases (IRDs) are both genetically and clinically highly heterogeneous and have long been considered incurable. Following the successful development of a gene augmentation therapy for biallelic RPE65-associated IRD, this view has changed. As a result, many different therapeutic approaches are currently being developed, in particular a large variety of molecular therapies. These are depending on the severity of the retinal degeneration, knowledge of the pathophysiological mechanism underlying each subtype of IRD, and the therapeutic target molecule. DNA therapies include approaches such as gene augmentation therapy, genome editing and optogenetics. For some genetic subtypes of IRD, RNA therapies and compound therapies have also shown considerable therapeutic potential. In this review, we summarize the current state-of-the-art of various therapeutic approaches, including the pros and cons of each strategy, and outline the future challenges that lie ahead in the combat against IRDs.
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Affiliation(s)
- Irene Vázquez-Domínguez
- Department of Human Genetics and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525GA Nijmegen, The Netherlands
| | - Alejandro Garanto
- Department of Human Genetics and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525GA Nijmegen, The Netherlands.
| | - Rob W J Collin
- Department of Human Genetics and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525GA Nijmegen, The Netherlands.
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19
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Genome Editing as a Treatment for the Most Prevalent Causative Genes of Autosomal Dominant Retinitis Pigmentosa. Int J Mol Sci 2019; 20:ijms20102542. [PMID: 31126147 PMCID: PMC6567127 DOI: 10.3390/ijms20102542] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 05/15/2019] [Accepted: 05/22/2019] [Indexed: 02/07/2023] Open
Abstract
: Inherited retinal dystrophies (IRDs) are a clinically and genetically heterogeneous group of diseases with more than 250 causative genes. The most common form is retinitis pigmentosa. IRDs lead to vision impairment for which there is no universal cure. Encouragingly, a first gene supplementation therapy has been approved for an autosomal recessive IRD. However, for autosomal dominant IRDs, gene supplementation therapy is not always pertinent because haploinsufficiency is not the only cause. Disease-causing mechanisms are often gain-of-function or dominant-negative, which usually require alternative therapeutic approaches. In such cases, genome-editing technology has raised hopes for treatment. Genome editing could be used to i) invalidate both alleles, followed by supplementation of the wild type gene, ii) specifically invalidate the mutant allele, with or without gene supplementation, or iii) to correct the mutant allele. We review here the most prevalent genes causing autosomal dominant retinitis pigmentosa and the most appropriate genome-editing strategy that could be used to target their different causative mutations.
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20
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Gaspar P, Almudi I, Nunes MDS, McGregor AP. Human eye conditions: insights from the fly eye. Hum Genet 2018; 138:973-991. [PMID: 30386938 DOI: 10.1007/s00439-018-1948-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 10/20/2018] [Indexed: 12/22/2022]
Abstract
The fruit fly Drosophila melanogaster has served as an excellent model to study and understand the genetics of many human diseases from cancer to neurodegeneration. Studying the regulation of growth, determination and differentiation of the compound eyes of this fly, in particular, have provided key insights into a wide range of diseases. Here we review the regulation of the development of fly eyes in light of shared aspects with human eye development. We also show how understanding conserved regulatory pathways in eye development together with the application of tools for genetic screening and functional analyses makes Drosophila a powerful model to diagnose and characterize the genetics underlying many human eye conditions, such as aniridia and retinitis pigmentosa. This further emphasizes the importance and vast potential of basic research to underpin applied research including identifying and treating the genetic basis of human diseases.
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Affiliation(s)
- Pedro Gaspar
- Department of Biological and Medical Sciences, Oxford Brookes University, Gipsy Lane, Oxford, OX3 0BP, UK
| | - Isabel Almudi
- Centro Andaluz de Biología del Desarrollo, CSIC/ Universidad Pablo de Olavide, Carretera de Utrera Km1, 41013, Sevilla, Spain
| | - Maria D S Nunes
- Department of Biological and Medical Sciences, Oxford Brookes University, Gipsy Lane, Oxford, OX3 0BP, UK
| | - Alistair P McGregor
- Department of Biological and Medical Sciences, Oxford Brookes University, Gipsy Lane, Oxford, OX3 0BP, UK.
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21
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Tsai YT, Wu WH, Lee TT, Wu WP, Xu CL, Park KS, Cui X, Justus S, Lin CS, Jauregui R, Su PY, Tsang SH. Clustered Regularly Interspaced Short Palindromic Repeats-Based Genome Surgery for the Treatment of Autosomal Dominant Retinitis Pigmentosa. Ophthalmology 2018; 125:1421-1430. [PMID: 29759820 PMCID: PMC6109419 DOI: 10.1016/j.ophtha.2018.04.001] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 03/29/2018] [Accepted: 04/02/2018] [Indexed: 01/02/2023] Open
Abstract
PURPOSE To develop a universal gene therapy to overcome the genetic heterogeneity in retinitis pigmentosa (RP) resulting from mutations in rhodopsin (RHO). DESIGN Experimental study for a combination gene therapy that uses both gene ablation and gene replacement. PARTICIPANTS This study included 2 kinds of human RHO mutation knock-in mouse models: RhoP23H and RhoD190N. In total, 23 RhoP23H/P23H, 43 RhoP23H/+, and 31 RhoD190N/+ mice were used for analysis. METHODS This study involved gene therapy using dual adeno-associated viruses (AAVs) that (1) destroy expression of the endogenous Rho gene in a mutation-independent manner via an improved clustered regularly interspaced short palindromic repeats-based gene deletion and (2) enable expression of wild-type protein via exogenous cDNA. MAIN OUTCOME MEASURES Electroretinographic and histologic analysis. RESULTS The thickness of the outer nuclear layer (ONL) after the subretinal injection of combination ablate-and-replace gene therapy was approximately 17% to 36% more than the ONL thickness resulting from gene replacement-only therapy at 3 months after AAV injection. Furthermore, electroretinography results demonstrated that the a and b waves of both RhoP23H and RhoD190N disease models were preserved more significantly using ablate-and-replace gene therapy (P < 0.001), but not by gene replacement monotherapy. CONCLUSIONS As a proof of concept, our results suggest that the ablate-and-replace strategy can ameliorate disease progression as measured by photoreceptor structure and function for both of the human mutation knock-in models. These results demonstrate the potency of the ablate-and-replace strategy to treat RP caused by different Rho mutations. Furthermore, because ablate-and-replace treatment is mutation independent, this strategy may be used to treat a wide array of dominant diseases in ophthalmology and other fields. Clinical trials using ablate-and-replace gene therapy would allow researchers to determine if this strategy provides any benefits for patients with diseases of interest.
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Affiliation(s)
- Yi-Ting Tsai
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, New York; Institute of Human Nutrition, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Wen-Hsuan Wu
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, New York
| | - Ting-Ting Lee
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, New York
| | - Wei-Pu Wu
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, New York
| | - Christine L Xu
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, New York
| | - Karen S Park
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, New York
| | - Xuan Cui
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, New York
| | - Sally Justus
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, New York
| | - Chyuan-Sheng Lin
- Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, New York
| | - Ruben Jauregui
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, New York; Weill Cornell Medical College, New York, New York
| | - Pei-Yin Su
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, New York
| | - Stephen H Tsang
- Jonas Children's Vision Care and Bernard & Shirlee Brown Glaucoma Laboratory, Departments of Ophthalmology, Pathology and Cell Biology, Columbia University, New York, New York; Institute of Human Nutrition, College of Physicians and Surgeons, Columbia University, New York, New York; Department of Ophthalmology, Edward S. Harkness Eye Institute, New York Presbyterian Hospital, New York, New York.
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22
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Pierce E. Genome Editing for Inherited Retinal Degenerations. Ophthalmology 2018; 125:1431-1432. [PMID: 30143094 DOI: 10.1016/j.ophtha.2018.06.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 06/06/2018] [Accepted: 06/07/2018] [Indexed: 11/17/2022] Open
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23
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Assessment of Safety and Functional Efficacy of Stem Cell-Based Therapeutic Approaches Using Retinal Degenerative Animal Models. Stem Cells Int 2017; 2017:9428176. [PMID: 28928775 PMCID: PMC5592015 DOI: 10.1155/2017/9428176] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2017] [Accepted: 06/19/2017] [Indexed: 02/06/2023] Open
Abstract
Dysfunction and death of retinal pigment epithelium (RPE) and or photoreceptors can lead to irreversible vision loss. The eye represents an ideal microenvironment for stem cell-based therapy. It is considered an “immune privileged” site, and the number of cells needed for therapy is relatively low for the area of focused vision (macula). Further, surgical placement of stem cell-derived grafts (RPE, retinal progenitors, and photoreceptor precursors) into the vitreous cavity or subretinal space has been well established. For preclinical tests, assessments of stem cell-derived graft survival and functionality are conducted in animal models by various noninvasive approaches and imaging modalities. In vivo experiments conducted in animal models based on replacing photoreceptors and/or RPE cells have shown survival and functionality of the transplanted cells, rescue of the host retina, and improvement of visual function. Based on the positive results obtained from these animal experiments, human clinical trials are being initiated. Despite such progress in stem cell research, ethical, regulatory, safety, and technical difficulties still remain a challenge for the transformation of this technique into a standard clinical approach. In this review, the current status of preclinical safety and efficacy studies for retinal cell replacement therapies conducted in animal models will be discussed.
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Gargini C, Novelli E, Piano I, Biagioni M, Strettoi E. Pattern of retinal morphological and functional decay in a light-inducible, rhodopsin mutant mouse. Sci Rep 2017; 7:5730. [PMID: 28720880 PMCID: PMC5516022 DOI: 10.1038/s41598-017-06045-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Accepted: 06/06/2017] [Indexed: 02/02/2023] Open
Abstract
Hallmarks of Retinitis Pigmentosa (RP), a family of genetic diseases, are a typical rod-cone-degeneration with initial night blindness and loss of peripheral vision, followed by decreased daylight sight and progressive visual acuity loss up to legal blindness. Great heterogeneity in nature and function of mutated genes, variety of mutations for each of them, variability in phenotypic appearance and transmission modality contribute to make RP a still incurable disease. Translational research relies on appropriate animal models mimicking the genetic and phenotypic diversity of the human pathology. Here, we provide a systematic, morphological and functional analysis of RhoTvrm4/Rho+ rhodopsin mutant mice, originally described in 2010 and portraying several features of common forms of autosomal dominant RP caused by gain-of-function mutations. These mice undergo photoreceptor degeneration only when exposed briefly to strong, white light and allow controlled timing of induction of rod and cone death, which therefore can be elicited in adult animals, as observed in human RP. The option to control severity and retinal extent of the phenotype by regulating intensity and duration of the inducing light opens possibilities to exploit this model for multiple experimental purposes. Altogether, the unique features of this mutant make it an excellent resource for retinal degeneration research.
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Affiliation(s)
| | | | - Ilaria Piano
- Department of Pharmacy, University of Pisa, Pisa, Italy
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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: 92] [Impact Index Per Article: 13.1] [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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Jones MK, Lu B, Girman S, Wang S. Cell-based therapeutic strategies for replacement and preservation in retinal degenerative diseases. Prog Retin Eye Res 2017; 58:1-27. [PMID: 28111323 PMCID: PMC5441967 DOI: 10.1016/j.preteyeres.2017.01.004] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 01/08/2017] [Accepted: 01/17/2017] [Indexed: 12/13/2022]
Abstract
Cell-based therapeutics offer diverse options for treating retinal degenerative diseases, such as age-related macular degeneration (AMD) and retinitis pigmentosa (RP). AMD is characterized by both genetic and environmental risks factors, whereas RP is mainly a monogenic disorder. Though treatments exist for some patients with neovascular AMD, a majority of retinal degenerative patients have no effective therapeutics, thus indicating a need for universal therapies to target diverse patient populations. Two main cell-based mechanistic approaches are being tested in clinical trials. Replacement therapies utilize cell-derived retinal pigment epithelial (RPE) cells to supplant lost or defective host RPE cells. These cells are similar in morphology and function to native RPE cells and can potentially supplant the responsibilities of RPE in vivo. Preservation therapies utilize supportive cells to aid in visual function and photoreceptor preservation partially by neurotrophic mechanisms. The goal of preservation strategies is to halt or slow the progression of disease and maintain remaining visual function. A number of clinical trials are testing the safety of replacement and preservation cell therapies in patients; however, measures of efficacy will need to be further evaluated. In addition, a number of prevailing concerns with regards to the immune-related response, longevity, and functionality of the grafted cells will need to be addressed in future trials. This review will summarize the current status of cell-based preclinical and clinical studies with a focus on replacement and preservation strategies and the obstacles that remain regarding these types of treatments.
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Affiliation(s)
- Melissa K Jones
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Bin Lu
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Sergey Girman
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA
| | - Shaomei Wang
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, 8700 Beverly Blvd., Los Angeles, CA 90048, USA; David Geffen School of Medicine, University of California Los Angeles, 10833 Le Conte Ave., Los Angeles, CA 90095, USA.
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A challenge to the striking genotypic heterogeneity of retinitis pigmentosa: a better understanding of the pathophysiology using the newest genetic strategies. Eye (Lond) 2016; 30:1542-1548. [PMID: 27564722 DOI: 10.1038/eye.2016.197] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Accepted: 07/13/2016] [Indexed: 11/08/2022] Open
Abstract
Retinitis pigmentosa (RP) is a group of inherited retinal disorders characterized by a complex association between tremendous genotypic multiplicity and great phenotypic heterogeneity. The severity of the clinical manifestation depends on penetrance and expressivity of the disease-gene. Also, various interactions between gene expression and environmental factors have been hypothesized. More than 250 genes with ~4500 causative mutations have been reported to be involved in different RP-related mechanisms. Nowadays, not more than the 50% of RPs are attributable to identified genes, whereas the rest of molecular defects are still undetectable, especially in populations where few genetic screenings have been performed. Therefore, new genetic strategies can be a remarkably useful tool to aid clinical diagnosis, potentially modifying treatment options, and family counseling. Genome-wide analytical techniques (array comparative genomic hybridization and single-nucleotide polymorphism genotyping) and DNA sequencing strategies (arrayed primer extension, Sanger sequencing, and ultra high-throughput sequencing) are successfully used to early make molecular diagnosis detecting single or multiple mutations in the huge heterogeneity of RPs. To date, further research needs to be carried out to better investigate the genotype/phenotype correlation, putting together genetic and clinical findings to provide detailed information concerning the risk of RP development and novel effective treatments.
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Retinal histopathology in eyes from patients with autosomal dominant retinitis pigmentosa caused by rhodopsin mutations. Graefes Arch Clin Exp Ophthalmol 2015. [PMID: 26202387 DOI: 10.1007/s00417-015-3099-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
PURPOSE To evaluate the histopathology in donor eyes from patients with autosomal dominant retinitis pigmentosa (ADRP) caused by p.P23H, p.P347T and p.P347L rhodopsin ( RHO ) gene mutations. METHODS Eyes from a 72-year-old male (donor 1), an 83-year-old female (donor 2), an 80-year-old female (donor 3), and three age-similar normal eyes were examined macroscopically, by scanning laser ophthalmoscopy and optical coherence tomography imaging. Perifoveal and peripheral pieces were processed for microscopy and immunocytochemistry with markers for photoreceptor cells. RESULTS DNA analysis revealed RHO mutations c.68C>A (p.P23H) in donor 1, c.1040C>T (p.P347L) in donor 2 and c.1039C>A (p.P347T) in donor 3. Histology of the ADRP eyes showed retinas with little evidence of stratified nuclear layers in the periphery and a prominent inner nuclear layer present in the perifoveal region in the p.P23H and p.P347T eyes, while it was severely atrophic in the p.P347L eye. The p.P23H and p.P347T mutations cause a profound loss of rods in both the periphery and perifovea, while the p.P347L mutation displays near complete absence of rods in both regions. All three rhodopsin mutations caused a profound loss of cones in the periphery. The p.P23H and p.P347T mutations led to the presence of highly disorganized cones in the perifovea. However, the p.P347L mutation led to near complete absence of cones also in the perifovea. CONCLUSIONS Our results support clinical findings indicating that mutations affecting residue P347 develop more severe phenotypes than those affecting P23. Furthermore, our results indicate a more severe phenotype in the p.P347L retina as compared to the p.P347T retina.
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