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Rohowetz LJ, Kunkler AL, Sengillo JD, Lazzarini TA, Lam BL, Berrocal AM. Choroideremia presenting as vision loss secondary to choroidal neovascularization. Ophthalmic Genet 2024; 45:175-179. [PMID: 37575054 DOI: 10.1080/13816810.2023.2245117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Revised: 06/23/2023] [Accepted: 08/01/2023] [Indexed: 08/15/2023]
Abstract
BACKGROUND Choroidal neovascularization (CNV) is a rare complication of choroideremia that occurs secondary to relative atrophy of the retinal pigment epithelium and eventual rupture of Bruch's membrane. The ideal management of CNV in choroideremia is unclear. MATERIALS AND METHODS Case report. OBSERVATIONS A 14-year-old male with no known ocular history presented to the eye emergency department complaining of a central scotoma in the right eye for 4 days. He had no past medical history and family history was unremarkable for known ocular disease. Visual acuity was 20/70 in the right eye and 20/30 in the left eye. Posterior segment exam revealed chorioretinal atrophy extending from the outer macula to the midperiphery in both eyes. There was CNV with associated subretinal hemorrhage in the right eye. Optical coherence tomography demonstrated the presence of CNV with subretinal fluid in the right eye and parafoveal outer retinal atrophy in both eyes. Genetic testing revealed a hemizygous exon 2 deletion on the CHM gene, pathogenic for choroideremia. The patient received a total of 3 injections 4 weeks apart followed by 1 injection 6 weeks later with resolution of the subretinal hemorrhage and reduction in CNV size with improvement in visual acuity to 20/20 at last follow-up exam. CONCLUSIONS AND IMPORTANCE Choroidal neovascularization is a rare cause of central vision loss in patients with choroideremia. In this report, we demonstrate a good functional and anatomic response to intravitreal bevacizumab in a 14-year-old patient with undiagnosed choroideremia who presented with CNV-induced central vision loss.
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Affiliation(s)
- Landon J Rohowetz
- Department of Ophthalmology, Bascom Palmer Eye Institute, Miami, Florida, USA
| | - Anne L Kunkler
- Department of Ophthalmology, Bascom Palmer Eye Institute, Miami, Florida, USA
| | - Jesse D Sengillo
- Department of Ophthalmology, Bascom Palmer Eye Institute, Miami, Florida, USA
| | - Thomas A Lazzarini
- Department of Ophthalmology, Bascom Palmer Eye Institute, Miami, Florida, USA
| | - Byron L Lam
- Department of Ophthalmology, Bascom Palmer Eye Institute, Miami, Florida, USA
| | - Audina M Berrocal
- Department of Ophthalmology, Bascom Palmer Eye Institute, Miami, Florida, USA
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2
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Xu P, Jiang YY, Morgan JIW. Cone Photoreceptor Morphology in Choroideremia Assessed Using Non-Confocal Split-Detection Adaptive Optics Scanning Light Ophthalmoscopy. Invest Ophthalmol Vis Sci 2023; 64:36. [PMID: 37504961 PMCID: PMC10383007 DOI: 10.1167/iovs.64.10.36] [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: 04/06/2023] [Accepted: 07/10/2023] [Indexed: 07/29/2023] Open
Abstract
Purpose Choroideremia (CHM) is an X-linked inherited retinal degeneration causing loss of the photoreceptors, retinal pigment epithelium, and choriocapillaris, although patients typically retain a central island of relatively preserved, functioning retina until late-stage disease. Here, we investigate cone photoreceptor morphology within the retained retinal island by examining cone inner segment area, density, circularity, and intercone space. Methods Using a custom-built, multimodal adaptive optics scanning light ophthalmoscope, nonconfocal split-detection images of the photoreceptor mosaic were collected at 1°, 2°, and 4° temporal to the fovea from 13 CHM and 12 control subjects. Cone centers were manually identified, and cone borders were segmented. A custom MATLAB script was used to extract area and circularity for each cone and calculate the percentage of intercone space in each region of interest. Bound cone density was also calculated. An unbalanced two-way ANOVA and Bonferroni post hoc tests were used to assess statistical differences between the CHM and control groups and along retinal eccentricity. Results Cone density was lower in the CHM group than in the control group (P < 0.001) and decreased with eccentricity from the fovea (P < 0.001). CHM cone inner segments were larger in area (P < 0.001) and more circular (P = 0.042) than those of the controls. Intercone space in CHM was also higher than in the controls (P < 0.001). Conclusions Cone morphology is altered in CHM compared to control, even within the centrally retained, functioning retinal area. Further studies are required to determine whether such morphology is a precursor to cone degeneration.
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Affiliation(s)
- Peiluo Xu
- Department of Bioengineering, School of Engineering and Applied Sciences, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Yu You Jiang
- Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
- Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Jessica I. W. Morgan
- Scheie Eye Institute, Department of Ophthalmology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
- Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania, Philadelphia, Pennsylvania, United States
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3
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Clinical and imaging findings of choroideremia in a pediatric patient due to a novel frameshift mutation. Am J Ophthalmol Case Rep 2022; 28:101718. [PMID: 36247208 PMCID: PMC9562444 DOI: 10.1016/j.ajoc.2022.101718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 09/15/2022] [Accepted: 10/02/2022] [Indexed: 11/21/2022] Open
Abstract
Purpose To describe the clinical characteristics, imaging findings and genetic testing results of a young simplex male with choroideremia. Observations A 6-year-old Hispanic-Chinese male was referred to the retina clinic for peripheral retinal pigmentary changes observed in both eyes on routine exam. The patient has an unremarkable family history and developmental history. Best corrected visual acuity was 20/25 in both eyes. Optical coherence tomography demonstrated attenuation of the ellipsoid and interdigitation zones. Widefield fundus autofluorescence demonstrated nummular hypo-autofluorescence peripherally in both eyes. Genetic testing revealed a variant originally described as a variant of uncertain significance (VUS) a c. 1775_1814del (p.Glu592Valfs*44) identified in the CHM gene, which was reclassified as pathogenic following segregation analysis. The patient was diagnosed with choroideremia due to a CHM pathogenic variant. Conclusions The multimodal imaging findings demonstrated here illustrate important clues to the diagnosis of Choroideremia in a simplex male.
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Widespread subclinical cellular changes revealed across a neural-epithelial-vascular complex in choroideremia using adaptive optics. Commun Biol 2022; 5:893. [PMID: 36100689 PMCID: PMC9470576 DOI: 10.1038/s42003-022-03842-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 08/12/2022] [Indexed: 11/08/2022] Open
Abstract
AbstractChoroideremia is an X-linked, blinding retinal degeneration with progressive loss of photoreceptors, retinal pigment epithelial (RPE) cells, and choriocapillaris. To study the extent to which these layers are disrupted in affected males and female carriers, we performed multimodal adaptive optics imaging to better visualize the in vivo pathogenesis of choroideremia in the living human eye. We demonstrate the presence of subclinical, widespread enlarged RPE cells present in all subjects imaged. In the fovea, the last area to be affected in choroideremia, we found greater disruption to the RPE than to either the photoreceptor or choriocapillaris layers. The unexpected finding of patches of photoreceptors that were fluorescently-labeled, but structurally and functionally normal, suggests that the RPE blood barrier function may be altered in choroideremia. Finally, we introduce a strategy for detecting enlarged cells using conventional ophthalmic imaging instrumentation. These findings establish that there is subclinical polymegathism of RPE cells in choroideremia.
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5
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OCT guided micro-focal ERG system with multiple stimulation wavelengths for characterization of ocular health. Sci Rep 2022; 12:4009. [PMID: 35256656 PMCID: PMC8901822 DOI: 10.1038/s41598-022-07622-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 01/31/2022] [Indexed: 11/25/2022] Open
Abstract
Inherited retinal disorders and dry age-related macular degeneration are characterized by the degeneration and death of different types of photoreceptors at different rate and locations. Advancement of new therapeutic interventions such as optogenetics gene therapy and cell replacement therapies are dependent on electrophysiological measurements at cellular resolution. Here, we report the development of an optical coherence tomography (OCT) guided micro-focal multi-color laser stimulation and electroretinogram (ERG) platform for highly localized monitoring of retina function. Functional evaluation of wild type and transgenic pigs affected by retinal degeneration was carried out using OCT guided micro-focal ERG (μfERG) with selected stimulation wavelengths for S, M and L cones as well as rod photoreceptors. In wild type pigs, μfERG allowed functional recording from rods and each type of cone photoreceptor cells separately. Furthermore, functional deficits in P23H transgenic pigs consistent with their retinal degeneration phenotype were observed, including decrease in the S and M cone function and lack of rod photoreceptor function. OCT guided μfERG based monitoring of physiological function will enable characterization of animal models of retinal degenerative diseases and evaluation of therapeutic interventions at the cellular level.
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Motozawa N, Miura T, Ochiai K, Yamamoto M, Horinouchi T, Tsuzuki T, Kanda GN, Ozawa Y, Tsujikawa A, Takahashi K, Takahashi M, Kurimoto Y, Maeda T, Mandai M. Automated evaluation of retinal pigment epithelium disease area in eyes with age-related macular degeneration. Sci Rep 2022; 12:892. [PMID: 35042966 PMCID: PMC8766591 DOI: 10.1038/s41598-022-05006-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 01/05/2022] [Indexed: 11/09/2022] Open
Abstract
The retinal pigment epithelium (RPE) is essential for the survival and function of retinal photoreceptor cells. RPE dysfunction causes various retinal diseases including age-related macular degeneration (AMD). Clinical studies on ES/iPS cell-derived RPE transplantation for RPE dysfunction-triggered diseases are currently underway. Quantification of the diseased RPE area is important to evaluate disease progression or the therapeutic effect of RPE transplantation. However, there are no standard protocols. To address this issue, we developed a 2-step software that enables objective and efficient quantification of RPE-disease area changes by analyzing the early-phase hyperfluorescent area in fluorescein angiography (FA) images. We extracted the Abnormal region. This extraction was based on deep learning-based discrimination. We scored the binarized extracted area using an automated program. Our program’s performance for the same eye from the serial image captures was within 3.1 ± 7.8% error. In progressive AMD, the trend was consistent with human assessment, even when FA images from two different visits were compared. This method was applicable to quantifying RPE-disease area changes over time, evaluating iPSC-RPE transplantation images, and a disease other than AMD. Our program may contribute to the assessment of the clinical course of RPE-disease areas in routine clinics and reduce the workload of researchers.
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Affiliation(s)
- Naohiro Motozawa
- Kobe City Eye Hospital, 2-1-8 Minatojima Minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan.,Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Takuya Miura
- Laboratory for Biologically Inspired Computing, RIKEN Center for Biosystems Dynamics Research, 6-2-3 Furuedai, Suita, Osaka, 565-0874, Japan
| | - Koji Ochiai
- Laboratory for Biologically Inspired Computing, RIKEN Center for Biosystems Dynamics Research, 6-2-3 Furuedai, Suita, Osaka, 565-0874, Japan
| | - Midori Yamamoto
- Kobe City Eye Hospital, 2-1-8 Minatojima Minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
| | - Takaaki Horinouchi
- Laboratory for Biologically Inspired Computing, RIKEN Center for Biosystems Dynamics Research, 6-2-3 Furuedai, Suita, Osaka, 565-0874, Japan
| | - Taku Tsuzuki
- Epistra Inc., 2-2-15 Hamamatsu-cho, Minato-ku, Tokyo, 105-0013, Japan
| | - Genki N Kanda
- Kobe City Eye Hospital, 2-1-8 Minatojima Minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan.,Laboratory for Biologically Inspired Computing, RIKEN Center for Biosystems Dynamics Research, 6-2-3 Furuedai, Suita, Osaka, 565-0874, Japan
| | - Yosuke Ozawa
- Epistra Inc., 2-2-15 Hamamatsu-cho, Minato-ku, Tokyo, 105-0013, Japan
| | - Akitaka Tsujikawa
- Department of Ophthalmology and Visual Sciences, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Koichi Takahashi
- Laboratory for Biologically Inspired Computing, RIKEN Center for Biosystems Dynamics Research, 6-2-3 Furuedai, Suita, Osaka, 565-0874, Japan
| | - Masayo Takahashi
- Kobe City Eye Hospital, 2-1-8 Minatojima Minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan.,VCCT Inc., Kobe Eye Center 5F, 2-1-8 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
| | - Yasuo Kurimoto
- Kobe City Eye Hospital, 2-1-8 Minatojima Minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
| | - Tadao Maeda
- Kobe City Eye Hospital, 2-1-8 Minatojima Minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan
| | - Michiko Mandai
- Kobe City Eye Hospital, 2-1-8 Minatojima Minamimachi, Chuo-ku, Kobe, Hyogo, 650-0047, Japan.
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7
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Kalatzis V, Roux AF, Meunier I. Molecular Therapy for Choroideremia: Pre-clinical and Clinical Progress to Date. Mol Diagn Ther 2021; 25:661-675. [PMID: 34661884 DOI: 10.1007/s40291-021-00558-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/09/2021] [Indexed: 12/01/2022]
Abstract
Choroideremia is an inherited retinal disease characterised by a degeneration of the light-sensing photoreceptors, supporting retinal pigment epithelium and underlying choroid. Patients present with the same symptoms as those with classic rod-cone dystrophy: (1) night blindness early in life; (2) progressive peripheral visual field loss, and (3) central vision decline with a slow progression to legal blindness. Choroideremia is monogenic and caused by mutations in CHM. Eight clinical trials (three phase 1/2, four phase 2, and one phase 3) have started (four of which are already finished) to evaluate the therapeutic efficacy of gene supplementation mediated by subretinal delivery of an adeno-associated virus serotype 2 (AAV2/2) vector expressing CHM. Furthermore, one phase 1 clinical trial has been initiated to evaluate the efficiency of a novel AAV variant to deliver CHM to the outer retina following intravitreal delivery. Lastly, a non-viral-mediated CHM replacement strategy is currently under development, which could lead to a future clinical trial. Here, we summarise the rationale behind these various studies, as well as any results published to date. The diversity of these trials currently places choroideremia at the forefront of the retinal gene therapy field. As a consequence, the trial outcomes, regardless of the results, have the potential to change the landscape of gene supplementation for inherited retinal diseases.
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Affiliation(s)
- Vasiliki Kalatzis
- Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm U1298, Hôpital St Eloi, 80 Avenue Augustin Fliche, 34091, Montpellier, France.
| | - Anne-Françoise Roux
- Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm U1298, Hôpital St Eloi, 80 Avenue Augustin Fliche, 34091, Montpellier, France.,Molecular Genetics Laboratory, Univ Montpellier, CHU Montpellier, Montpellier, France
| | - Isabelle Meunier
- Institute for Neurosciences of Montpellier, Univ Montpellier, Inserm U1298, Hôpital St Eloi, 80 Avenue Augustin Fliche, 34091, Montpellier, France.,National Reference Centre for Inherited Sensory Diseases, University of Montpellier, CHU Montpellier, Montpellier, France
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8
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Zhai Y, Oke S, MacDonald IM. Validating Ellipsoid Zone Area Measurement With Multimodal Imaging in Choroideremia. Transl Vis Sci Technol 2021; 10:17. [PMID: 34111265 PMCID: PMC8132016 DOI: 10.1167/tvst.10.6.17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To assess en face ellipsoid zone (EZ) maps of remaining retinal structure as outcome measures for the future clinical research in patients with choroideremia. Methods Twenty eyes from 12 patients with a confirmed genetic diagnosis of choroideremia were included retrospectively from a single site. From spectral domain-optical coherence tomography volume scans, slabs including the EZ were manually segmented to create the en face EZ maps. The preserved EZ area was measured by two graders. Lengths of the EZ were recorded at 0°, 45°, 90°, and 135°. The intraclass correlation coefficients and Bland–Altman plots were used to show intergrader agreement. The Pearson correlation coefficient evaluated the correlation between length and area. A Bland–Altman plot compared en face EZ and the preserved fundus autofluorescence area. Results Measurements of EZ area by two graders showed excellent agreement with an intraclass correlation coefficient of 0.992 (95% confidence interval, 0.980–0.997). A Pearson correlation analysis showed that the existing marker for preserved photoreceptor (horizontal EZ length) was correlated with the area (r = 0.722). The average EZ length in four meridians showed a much better correlation with the EZ area (r = 0.929). The fundus autofluorescence area was found to be a mean of 0.45 ± 0.99 mm2 greater than the EZ area. Conclusions EZ area measurement provides excellent intergrader reliability, although the process is time consuming. We propose a less time-consuming alternative to estimate the EZ by using the average EZ band length in meridians. Our data also suggest that the loss of photoreceptor inner segments is an early change in choroideremia and may happen before the loss of the retinal pigment epithelium. Translational Relevance En face EZ mapping is a potential tool for future clinical trials to quantify preserved photoreceptor structure in choroideremia.
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Affiliation(s)
- Yi Zhai
- Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Sarah Oke
- Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Ian M MacDonald
- Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton, Alberta, Canada
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9
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Garita-Hernandez M, Chaffiol A, Guibbal L, Routet F, Khabou H, Riancho L, Toualbi L, Picaud S, Sahel JA, Goureau O, Duebel J, Dalkara D. Control of Microbial Opsin Expression in Stem Cell Derived Cones for Improved Outcomes in Cell Therapy. Front Cell Neurosci 2021; 15:648210. [PMID: 33815066 PMCID: PMC8012682 DOI: 10.3389/fncel.2021.648210] [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: 12/31/2020] [Accepted: 02/23/2021] [Indexed: 12/11/2022] Open
Abstract
Human-induced pluripotent stem cell (hiPSC) derived organoids have become increasingly used systems allowing 3D-modeling of human organ development, and disease. They are also a reliable source of cells for transplantation in cell therapy and an excellent model to validate gene therapies. To make full use of these systems, a toolkit of genetic modification techniques is necessary to control their activity in line with the downstream application. We have previously described adeno-associated viruse (AAV) vectors for efficient targeting of cells within human retinal organoids. Here, we describe biological restriction and enhanced gene expression in cone cells of such organoids thanks to the use of a 1.7-kb L-opsin promoter. We illustrate the usefulness of implementing such a promoter to enhance the expression of the red-shifted opsin Jaws in fusion with a fluorescent reporter gene, enabling cell sorting to enrich the desired cell population. Increased Jaws expression after transplantation improved light responses promising better therapeutic outcomes in a cell therapy setting. Our results point to the importance of promoter activity in restricting, improving, and controlling the kinetics of transgene expression during the maturation of hiPSC retinal derivatives. Differentiation requires mechanisms to initiate specific transcriptional changes and to reinforce those changes when mature cell states are reached. By employing a cell-type-specific promoter we put transgene expression under the new transcriptional program of mature cells.
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Affiliation(s)
| | | | - Laure Guibbal
- Institut de la Vision, Sorbonne Université, Paris, France
| | - Fiona Routet
- Institut de la Vision, Sorbonne Université, Paris, France
| | - Hanen Khabou
- Institut de la Vision, Sorbonne Université, Paris, France
| | - Luisa Riancho
- Institut de la Vision, Sorbonne Université, Paris, France
| | - Lyes Toualbi
- Institut de la Vision, Sorbonne Université, Paris, France
| | - Serge Picaud
- Institut de la Vision, Sorbonne Université, Paris, France
| | - José-Alain Sahel
- Institut de la Vision, Sorbonne Université, Paris, France
- CHNO des Quinze−Vingts, DHU Sight Restore, Paris, France
- Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | | | - Jens Duebel
- Institut de la Vision, Sorbonne Université, Paris, France
- Department of Ophthalmology, University Medical Center Göttingen, Göttingen, Germany
| | - Deniz Dalkara
- Institut de la Vision, Sorbonne Université, Paris, France
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10
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Zeitz C, Nassisi M, Laurent-Coriat C, Andrieu C, Boyard F, Condroyer C, Démontant V, Antonio A, Lancelot ME, Frederiksen H, Kloeckener-Gruissem B, El-Shamieh S, Zanlonghi X, Meunier I, Roux AF, Mohand-Saïd S, Sahel JA, Audo I. CHM mutation spectrum and disease: An update at the time of human therapeutic trials. Hum Mutat 2021; 42:323-341. [PMID: 33538369 DOI: 10.1002/humu.24174] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 12/21/2020] [Accepted: 01/20/2021] [Indexed: 12/15/2022]
Abstract
Choroideremia is an X-linked inherited retinal disorder (IRD) characterized by the degeneration of retinal pigment epithelium, photoreceptors, choriocapillaris and choroid affecting males with variable phenotypes in female carriers. Unlike other IRD, characterized by a large clinical and genetic heterogeneity, choroideremia shows a specific phenotype with causative mutations in only one gene, CHM. Ongoing gene replacement trials raise further interests in this disorder. We describe here the clinical and genetic data from a French cohort of 45 families, 25 of which carry novel variants, in the context of 822 previously reported choroideremia families. Most of the variants represent loss-of-function mutations with eleven families having large (i.e. ≥6 kb) genomic deletions, 18 small insertions, deletions or insertion deletions, six showing nonsense variants, eight splice site variants and two missense variants likely to affect splicing. Similarly, 822 previously published families carry mostly loss-of-function variants. Recurrent variants are observed worldwide, some of which linked to a common ancestor, others arisen independently in specific CHM regions prone to mutations. Since all exons of CHM may harbor variants, Sanger sequencing combined with quantitative polymerase chain reaction or multiplex ligation-dependent probe amplification experiments are efficient to achieve the molecular diagnosis in patients with typical choroideremia features.
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Affiliation(s)
- Christina Zeitz
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Marco Nassisi
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Camille Andrieu
- CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC1423, Paris, France
| | - Fiona Boyard
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Vanessa Démontant
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Aline Antonio
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | | | - Helen Frederiksen
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Barbara Kloeckener-Gruissem
- Institute of Medical Molecular Genetics, University of Zurich, Schlieren, Switzerland.,Department of Biology, ETH Zurich, Zurich, Switzerland
| | - Said El-Shamieh
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,Department of Medical Laboratory Technology, Faculty of Health Sciences, Beirut Arab University, Beirut, Lebanon
| | - Xavier Zanlonghi
- Clinique Pluridisciplinaire Jules Verne, Institut Ophtalmologique de l'Ouest, Nantes, France
| | - Isabelle Meunier
- National Reference Centre for Inherited Sensory Diseases, University of Montpellier, Montpellier University Hospital, Montpellier, France.,Institute for Neurosciences of Montpellier (INM), University of Montpellier, INSERM, Montpellier, France
| | - Anne-Françoise Roux
- Laboratoire de Génétique Moléculaire, CHU de Montpellier, Université de Montpellier, Montpellier, France
| | - Saddek Mohand-Saïd
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC1423, Paris, France
| | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC1423, Paris, France.,Fondation Ophtalmologique Adolphe de Rothschild, Paris, France.,Académie des Sciences-Institut de France, Paris, France.,Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Isabelle Audo
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France.,CHNO des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC1423, Paris, France.,Department of Genetics, UCL-Institute of Ophthalmology, London, UK
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11
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Abstract
PURPOSE Choroideremia (CHM) is a rare inherited retinal degeneration resulting from mutation of the CHM gene, which results in absence of functional Rab escort protein 1 (REP1). We evaluated retinal gene therapy with an adeno-associated virus vector that used to deliver a functional version of the CHM gene (AAV2-REP1). METHODS THOR (NCT02671539) is a Phase 2, open-label, single-center, randomized study. Six male patients (51-60 years) with CHM received AAV2-REP1, by a single 0.1-mL subretinal injection of 10 genome particles during vitrectomy. Twelve-month data are reported. RESULTS In study eyes, 4 patients experienced minor changes in best-corrected visual acuity (-4 to +1 Early Treatment Diabetic Retinopathy Study [ETDRS] letters); one gained 17 letters and another lost 14 letters. Control eyes had changes of -2 to +4 letters. In 5/6 patients, improvements in mean (95% confidence intervals) retinal sensitivity (2.3 [4.0] dB), peak retinal sensitivity (2.8 [3.5] dB), and gaze fixation area (-36.1 [66.9] deg) were recorded. Changes in anatomical endpoints were similar between study and control eyes. Adverse events were consistent with the surgical procedure. CONCLUSION Gene therapy with AAV2-REP1 can maintain, and in some cases, improve, visual acuity in CHM. Longer term follow-up is required to establish whether these benefits are maintained.
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12
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Muftuoglu IK, Al-Sheikh M, J S, Rasheed MA, Singh SR, Chhablani J. Imaging in inherited retinal disorders. Eur J Ophthalmol 2021; 31:1656-1676. [PMID: 33525895 DOI: 10.1177/1120672121990578] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Inherited retinal diseases, which results from mutations in over 260 identified genes, affect more than 2 million people globally. The diseases mostly cause severe vision loss in young working population and have severe impact on social economic status of the population. Advances in retinal imaging techniques along with developments in gene identification and cell biology techniques have yielded to a better understanding of the genetic and biochemical mechanisms causing these diseases. Retinal imaging along with through ophthalmological examination is essential to make an accurate diagnosis, to decrease the burden of unneccessary anciliary tests and to select the potential patients that can get benefit from the gene treatment. The purpose of the review is to yield an update on inherited retinal diseases by highlighting microstructural changes in retina and to summarize the retinal changes detected by currently available multimodal imaging techniques.
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Affiliation(s)
- Ilkay Kilic Muftuoglu
- Department of Ophthalmology, Istanbul Training and Research Hospital, Istanbul, Turkey
| | - Mayss Al-Sheikh
- Department of Ophthalmology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Sushma J
- LV Prasad Eye Institute, Hyderabad, Telangana, India
| | | | - Sumit Randhir Singh
- Jacobs Retina Center at Shiley Eye Center, University of California, San Diego, La Jolla, CA, USA
| | - Jay Chhablani
- UPMC Eye Center, University of Pittsburgh, Pittsburgh, PA, USA
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Abstract
PURPOSE Choroideremia is an incurable, X-linked, recessive retinal dystrophy caused by loss of function mutations in the CHM gene. It is estimated to affect approximately 1 in 50,000 male patients. It is characterized by progressive degeneration of the retinal pigment epithelium, choroid, and photoreceptors, resulting in visual impairment and blindness. There is an unmet need in choroideremia, because currently, there are no approved treatments available for patients with the disease. METHODS We review the patient journey, societal impact, and emerging treatments for patients with choroideremia. RESULTS Its relative rarity and similarities with other retinal diseases in early years mean that diagnosis of choroideremia can often be delayed. Furthermore, its impact on affected individuals, and wider society, is also likely underestimated. AAV2-mediated gene therapy is an investigational treatment that aims to replace the faulty CHM gene. Early-phase studies reported potentially important visual acuity gains and maintenance of vision in some patients, and a large Phase 3 program is now underway. CONCLUSION Choroideremia is a disease with a significant unmet need. Interventions that can treat progression of the disease and improve visual and functional outcomes have the potential to reduce health care costs and enhance patient quality of life.
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Ortiz-Ramirez GY, Villanueva-Mendoza C, Zenteno Ruiz JC, Reyes M, Cortés-González V. Autofluorescence in female carriers with choroideremia: A familial case with a novel mutation in the CHM gene. Ophthalmic Genet 2020; 41:625-628. [PMID: 32835561 DOI: 10.1080/13816810.2020.1810283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
BACKGROUND Choroideremia is an X-linked chorioretinal dystrophy caused by mutations in the CHM gene. The main differential diagnosis is X-linked retinitis pigmentosa. Clinically, male patients that are affected by these two diseases have similar symptoms. This work aims to report a familial case of choroideremia initially diagnosed as X-linked retinitis pigmentosa with a novel mutation in the CHM gene, and the relevance of fundus autofluorescence (FAF) in female carriers. MATERIALS AND METHODS A complete ophthalmological evaluation was done in a 37-year-old woman and her 53-year-old maternal uncle; the uncle had been diagnosed previously with X-linked retinitis pigmentosa. A visual field test, FAF imaging, full-field electroretinography, and a genetic test were performed. RESULTS In the proband, the fundoscopy revealed diffuse changes in the retinal pigment epithelium in both eyes, and the FAF showed a speckled pattern of low- and high-density. The maternal uncle's ophthalmological evaluation showed choroidal and retinal atrophy consistent with choroideremia. The molecular analysis revealed a pathogenic variant in the CHM gene, c.190-1 G > T. CONCLUSIONS In female carriers of choroideremia and X-linked retinitis pigmentosa, differential diagnosis may be challenging. A speckled pattern of low- and high-density in autofluorescence is commonly found in female carriers of choroideremia. FAF is a powerful tool for making a correct clinical diagnosis because the pattern in FAF is much more apparent than the visible retinal changes obtained by fundoscopy. Although it is crucial to perform molecular analysis to confirm the diagnosis, FAF is useful when genetic testing may not be readily available.
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Affiliation(s)
- Grecia Yael Ortiz-Ramirez
- Ophthalmology, Hospital "Dr. Luis Sánchez Bulnes" Asociación Para Evitar la Ceguera en México, Coyoacán, México
| | | | - Juan Carlos Zenteno Ruiz
- Research Unit and Genetics, Institute of Ophthalmology "Conde de Valenciana" Foundation, Mexico City, Mexico.,Department of Biochemistry, Faculty of Medicine, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Mariana Reyes
- Genetics, Hospital "Dr. Luis Sánchez Bulnes" Asociación Para Evitar la Ceguera en México, Coyoacán, México
| | - Vianney Cortés-González
- Genetics, Hospital "Dr. Luis Sánchez Bulnes" Asociación Para Evitar la Ceguera en México, Coyoacán, México
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Maldonado R, Jalil S, Wartiovaara K. Curative gene therapies for rare diseases. J Community Genet 2020; 12:267-276. [PMID: 32803721 PMCID: PMC8141081 DOI: 10.1007/s12687-020-00480-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 07/29/2020] [Indexed: 02/06/2023] Open
Abstract
Diseases caused by alterations in the DNA can be overcome by providing the cells or tissues with a functional copy of the mutated gene. The most common form of gene therapy implies adding an extra genetic unit into the cell. However, new genome engineering techniques also allow the modification or correction of the existing allele, providing new possibilities, especially for dominant diseases. Gene therapies have been tested for 30 years in thousands of clinical trials, but presently, we have only three authorised gene therapy products for the treatment of inherited diseases in European Union. Here, we describe the gene therapy alternatives already on the market in the European Union and expand the scope to some clinical trials. Additionally, we discuss the ethical and regulatory issues raised by the development of these new kinds of therapies.
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Affiliation(s)
- Rocio Maldonado
- Stem Cells and Metabolism Research Program, University of Helsinki, Helsinki, Finland
| | - Sami Jalil
- Stem Cells and Metabolism Research Program, University of Helsinki, Helsinki, Finland
| | - Kirmo Wartiovaara
- Stem Cells and Metabolism Research Program, University of Helsinki, Helsinki, Finland.
- Clinical Genetics, Helsinki University Hospital, Helsinki, Finland.
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16
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Brambati M, Borrelli E, Sacconi R, Bandello F, Querques G. Choroideremia: Update On Clinical Features And Emerging Treatments. Clin Ophthalmol 2019; 13:2225-2231. [PMID: 31819346 PMCID: PMC6874149 DOI: 10.2147/opth.s195564] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 11/05/2019] [Indexed: 12/21/2022] Open
Abstract
Choroideremia (CHM) is an X-linked chorioretinal dystrophy characterized by progressive degeneration of the choroid, retinal pigment epithelium and retina. This disease is caused by mutations in the X-linked CHM gene encoding a Ras-related GTPase Rab escort protein (REP)-1, which is extremely important for the retinal function. Clinically, male-affected patients have a progressive reduction in visual acuity. This disease is formally considered incurable, although new promising treatments have been recently introduced. In this article, a review of the salient pathogenetic features of choroideremia, essential for the proper interpretation of therapeutic approaches, is followed by a discussion of the fundamental clinical features of this hereditary disease. Finally, relevant new therapeutic approaches in this disease will be discussed, including gene therapy, stem cells, small molecules, and retinal prosthesis.
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Affiliation(s)
- Maria Brambati
- Ophthalmology Department, San Raffaele University Hospital, Milan, Italy
| | - Enrico Borrelli
- Ophthalmology Department, San Raffaele University Hospital, Milan, Italy
| | - Riccardo Sacconi
- Ophthalmology Department, San Raffaele University Hospital, Milan, Italy
| | - Francesco Bandello
- Ophthalmology Department, San Raffaele University Hospital, Milan, Italy
| | - Giuseppe Querques
- Ophthalmology Department, San Raffaele University Hospital, Milan, Italy
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17
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Zhang Y, Wang Z, Huang S, Sun L, Zhao S, Zhong Y, Xiao H, Ding X. Parents' perceptions of diagnostic genetic testing for children with inherited retinal disease in China. Mol Genet Genomic Med 2019; 7:e916. [PMID: 31373165 PMCID: PMC6732314 DOI: 10.1002/mgg3.916] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 07/18/2019] [Accepted: 07/19/2019] [Indexed: 01/20/2023] Open
Abstract
Background In this study, we aim to investigate the awareness of, attitudes toward, and experiences with diagnostic genetic testing among parents of children suspected of having inherited retinal disease (IRDs) in China. Methods Semistructured, face‐to‐face, and in‐depth interviews were carried out with parents of children with suspected IRDs in this qualitative study. Inductive content analysis was used for data processing. Results Forty‐six parents participated in our interviews, and 47.8% of them supported genetic testing for following four main reasons: to help in making informed reproductive health decisions, to prepare for novel potential treatment, to identify the underlying causes of IRDs, and to satisfy curiosity about the heredity of IRDs. Among them, 19.6% were opposed to the testing for four main reasons, namely lack of therapeutic benefit, difficulty in affording the testing cost, doubt in the accuracy of clinical diagnosis, and the presence of concerns about the limitations of genetic testing. 47.8% of the parents expressed concerns that the genetic findings might lead to potential psychological stress. Conclusion In this study, we showed that nearly half of the parents supported genetic testing mainly for family planning, and a fifth of the parents were opposed to the testing mainly for lack of therapeutic benefit. Moreover, half of the parents expressed concern that a positive genetic result may create potential psychological burden to the parents and children.
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Affiliation(s)
- Yu Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Zhirong Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Sijian Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Limei Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Shiying Zhao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yimin Zhong
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Huiming Xiao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Xiaoyan Ding
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
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18
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Antisense Oligonucleotide-Based Splice Correction of a Deep-Intronic Mutation in CHM Underlying Choroideremia. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1074:83-89. [PMID: 29721931 DOI: 10.1007/978-3-319-75402-4_11] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Choroideremia is a progressive genetic eye disorder caused by mutations in the CHM gene that encodes the Rab escort protein-1 (REP-1). One of the many CHM mutations described so far is a deep-intronic variant, c.315-4587T>A, that creates a novel splice acceptor site resulting in the insertion of a 98-bp pseudoexon in the CHM transcript. Antisense oligonucleotides (AONs) are a potential therapeutic tool for correcting splice defects, as they have the properties to bind to the pre-mRNA and redirect the splicing process. Previously, we used AONs to correct aberrant splicing events caused by a recurrent intronic mutation in CEP290 underlying Leber congenital amaurosis. Here, we expand the use of these therapeutic molecules for the c.315-4587T>A deep-intronic mutation in CHM by demonstrating splice correction in patient-derived lymphoblast cells.
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Ong T, Pennesi ME, Birch DG, Lam BL, Tsang SH. Adeno-Associated Viral Gene Therapy for Inherited Retinal Disease. Pharm Res 2019; 36:34. [PMID: 30617669 PMCID: PMC6534121 DOI: 10.1007/s11095-018-2564-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 12/13/2018] [Indexed: 01/17/2023]
Abstract
Inherited retinal diseases (IRDs) are a group of rare, heterogenous eye disorders caused by gene mutations that result in degeneration of the retina. There are currently limited treatment options for IRDs; however, retinal gene therapy holds great promise for the treatment of different forms of inherited blindness. One such IRD for which gene therapy has shown positive initial results is choroideremia, a rare, X-linked degenerative disorder of the retina and choroid. Mutation of the CHM gene leads to an absence of functional Rab escort protein 1 (REP1), which causes retinal pigment epithelium cell death and photoreceptor degeneration. The condition presents in childhood as night blindness, followed by progressive constriction of visual fields, generally leading to vision loss in early adulthood and total blindness thereafter. A recently developed adeno-associated virus-2 (AAV2) vector construct encoding REP1 (AAV2-REP1) has been shown to deliver a functional version of the CHM gene into the retinal pigment epithelium and photoreceptor cells. Phase 1 and 2 studies of AAV2-REP1 in patients with choroideremia have produced encouraging results, suggesting that it is possible not only to slow or stop the decline in vision following treatment with AAV2-REP1, but also to improve visual acuity in some patients.
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Affiliation(s)
- Tuyen Ong
- Nightstar Therapeutics, 203 Crescent Street, Suite 303, Waltham, Massachusetts, 02453, USA.
| | - Mark E Pennesi
- Casey Eye Institute, Oregon Health & Science University, Portland, Oregon, USA
| | - David G Birch
- Retina Foundation of the Southwest, Dallas, Texas, USA
| | - Byron L Lam
- Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Stephen H Tsang
- Department of Ophthalmology and of Pathology and Cell Biology, Columbia University, New York, New York, USA
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20
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The effect of PTC124 on choroideremia fibroblasts and iPSC-derived RPE raises considerations for therapy. Sci Rep 2018; 8:8234. [PMID: 29844446 PMCID: PMC5974348 DOI: 10.1038/s41598-018-26481-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 05/04/2018] [Indexed: 11/24/2022] Open
Abstract
Inherited retinal dystrophies (IRDs) are caused by mutations in over 200 genes, resulting in a range of therapeutic options. Translational read-through inducing drugs (TRIDs) offer the possibility of treating multiple IRDs regardless of the causative gene. TRIDs promote ribosomal misreading of premature stop codons, which results in the incorporation of a near-cognate amino acid to produce a full-length protein. The IRD choroideremia (CHM) is a pertinent candidate for TRID therapy, as nonsense variants cause 30% of cases. Recently, treatment of the UAA nonsense-carrying CHM zebrafish model with the TRID PTC124 corrected the underlying biochemical defect and improved retinal phenotype. To be clinically relevant, we studied PTC124 efficiency in UAA nonsense-carrying human fibroblasts and induced pluripotent stem cell-derived retinal pigment epithelium, as well as in a UAA-mutated CHM overexpression system. We showed that PTC124 treatment induces a non-significant trend for functional rescue, which could not be improved by nonsense-mediated decay inhibition. Furthermore, it does not produce a detectable CHM-encoded protein even when coupled with a proteasome inhibitor. We suggest that drug efficiency may depend upon on the target amino acid and its evolutionary conservation, and argue that patient cells should be screened in vitro prior to inclusion in a clinical trial.
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21
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Torriano S, Erkilic N, Faugère V, Damodar K, Hamel CP, Roux AF, Kalatzis V. Pathogenicity of a novel missense variant associated with choroideremia and its impact on gene replacement therapy. Hum Mol Genet 2018; 26:3573-3584. [PMID: 28911202 DOI: 10.1093/hmg/ddx244] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 06/19/2017] [Indexed: 12/15/2022] Open
Abstract
Choroideremia (CHM) is an inherited retinal dystrophy characterised by progressive degeneration of photoreceptors, retinal pigment epithelium (RPE) and underlying choroid. It is caused by loss-of-function mutations in CHM, which has an X-linked inheritance, and is thus an ideal candidate for gene replacement strategies. CHM encodes REP1, which plays a key role in the prenylation of Rab GTPases. We recently showed that an induced pluripotent stem cell (iPSc)-derived RPE model for CHM is fully functional and reproduces the underlying prenylation defect. This criterion can thus be used for testing the pathogenic nature of novel variants. Until recently, missense variants were not associated with CHM. Currently, at least nine such variants have been reported but only two have been shown to be pathogenic. We report here the characterisation of the third pathogenic missense CHM variant, p.Leu457Pro. Clinically, the associated phenotype is indistinguishable from that of loss-of-function mutations. By contrast, this missense variant results in wild type CHM expression levels and detectable levels of mutant protein. The prenylation status of patient-specific fibroblasts and iPSc-derived RPE is within the range observed for loss-of-function mutations, consistent with the clinical phenotype. Lastly, considering the current climate of CHM gene therapy, we assayed whether the presence of mutant REP1 could interfere with a gene replacement strategy by testing the prenylation status of patient-specific iPSc-derived RPE following AAV-mediated gene transfer. Our results show that correction of the functional defect is possible and highlight the predictive value of these models for therapy screening prior to inclusion in clinical trials.
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Affiliation(s)
- Simona Torriano
- Inserm U1051, Institute for Neurosciences of Montpellier, Montpellier, France.,University of Montpellier, Montpellier, France
| | - Nejla Erkilic
- Inserm U1051, Institute for Neurosciences of Montpellier, Montpellier, France.,University of Montpellier, Montpellier, France
| | | | - Krishna Damodar
- Inserm U1051, Institute for Neurosciences of Montpellier, Montpellier, France.,University of Montpellier, Montpellier, France
| | - Christian P Hamel
- Inserm U1051, Institute for Neurosciences of Montpellier, Montpellier, France.,University of Montpellier, Montpellier, France.,Department of Ophthalmology, CHRU, Montpellier, France.,Centre of Reference for Genetic Sensory Diseases, CHRU, Montpellier, France
| | - Anne-Francoise Roux
- Laboratory of Molecular Genetics, CHRU, Montpellier, France.,Laboratory of Rare Genetic Diseases, EA 7402, University of Montpellier, Montpellier, France
| | - Vasiliki Kalatzis
- Inserm U1051, Institute for Neurosciences of Montpellier, Montpellier, France.,University of Montpellier, Montpellier, France
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22
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Murro V, Mucciolo DP, Passerini I, Palchetti S, Sodi A, Virgili G, Rizzo S. Retinal dystrophy and subretinal drusenoid deposits in female choroideremia carriers. Graefes Arch Clin Exp Ophthalmol 2017; 255:2099-2111. [DOI: 10.1007/s00417-017-3751-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 06/22/2017] [Accepted: 07/10/2017] [Indexed: 11/30/2022] Open
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23
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Zulliger R, Conley SM, Naash MI. Non-viral therapeutic approaches to ocular diseases: An overview and future directions. J Control Release 2015; 219:471-487. [PMID: 26439665 PMCID: PMC4699668 DOI: 10.1016/j.jconrel.2015.10.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Revised: 10/01/2015] [Accepted: 10/02/2015] [Indexed: 12/31/2022]
Abstract
Currently there are no viable treatment options for patients with debilitating inherited retinal degeneration. The vast variability in disease-inducing mutations and resulting phenotypes has hampered the development of therapeutic interventions. Gene therapy is a logical approach, and recent work has focused on ways to optimize vector design and packaging to promote optimized expression and phenotypic rescue after intraocular delivery. In this review, we discuss ongoing ocular clinical trials, which currently use viral gene delivery, but focus primarily on new advancements in optimizing the efficacy of non-viral gene delivery for ocular diseases. Non-viral delivery systems are highly customizable, allowing functionalization to improve cellular and nuclear uptake, bypassing cellular degradative machinery, and improving gene expression in the nucleus. Non-viral vectors often yield transgene expression levels lower than viral counterparts, however their favorable safety/immune profiles and large DNA capacity (critical for the delivery of large ocular disease genes) make their further development a research priority. Recent work on particle coating and vector engineering presents exciting ways to overcome limitations of transient/low gene expression levels, but also highlights the fact that further refinements are needed before use in the clinic.
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Affiliation(s)
- Rahel Zulliger
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204-5060, United States
| | - Shannon M Conley
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, United States
| | - Muna I Naash
- Department of Biomedical Engineering, University of Houston, Houston, TX 77204-5060, United States.
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Fine I, Cepko CL, Landy MS. Vision research special issue: Sight restoration: Prosthetics, optogenetics and gene therapy. Vision Res 2015; 111:115-23. [PMID: 25937376 DOI: 10.1016/j.visres.2015.04.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Ione Fine
- Department of Psychology, University of Washington, Seattle, WA, USA
| | - Connie L Cepko
- Departments of Genetics and Ophthalmology, Howard Hughes Medical Institute, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA
| | - Michael S Landy
- Department of Psychology and Center for Neural Science, New York University, New York, NY, USA
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25
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Ben M’Barek K, Regent F, Monville C. Use of human pluripotent stem cells to study and treat retinopathies. World J Stem Cells 2015; 7:596-604. [PMID: 25914766 PMCID: PMC4404394 DOI: 10.4252/wjsc.v7.i3.596] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 11/13/2014] [Accepted: 12/31/2014] [Indexed: 02/06/2023] Open
Abstract
Human cell types affected by retinal diseases (such as age-related macular degeneration or retinitis pimentosa) are limited in cell number and of reduced accessibility. As a consequence, their isolation for in vitro studies of disease mechanisms or for drug screening efforts is fastidious. Human pluripotent stem cells (hPSCs), either of embryonic origin or through reprogramming of adult somatic cells, represent a new promising way to generate models of human retinopathies, explore the physiopathological mechanisms and develop novel therapeutic strategies. Disease-specific human embryonic stem cells were the first source of material to be used to study certain disease states. The recent demonstration that human somatic cells, such as fibroblasts or blood cells, can be genetically converted to induce pluripotent stem cells together with the continuous improvement of methods to differentiate these cells into disease-affected cellular subtypes opens new perspectives to model and understand a large number of human pathologies, including retinopathies. This review focuses on the added value of hPSCs for the disease modeling of human retinopathies and the study of their molecular pathological mechanisms. We also discuss the recent use of these cells for establishing the validation studies for therapeutic intervention and for the screening of large compound libraries to identify candidate drugs.
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26
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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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