1
|
Luo LL, Xu J, Wang BQ, Chen C, Chen X, Hu QM, Wang YQ, Zhang WY, Jiang WX, Li XT, Zhou H, Xiao X, Zhao K, Lin S. A novel capsid-XL32-derived adeno-associated virus serotype prompts retinal tropism and ameliorates choroidal neovascularization. Biomaterials 2024; 304:122403. [PMID: 38016335 DOI: 10.1016/j.biomaterials.2023.122403] [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: 06/19/2023] [Revised: 10/24/2023] [Accepted: 11/14/2023] [Indexed: 11/30/2023]
Abstract
Gene therapy has been adapted, from the laboratory to the clinic, to treat retinopathies. In contrast to subretinal route, intravitreal delivery of AAV vectors displays the advantage of bypassing surgical injuries, but the viral particles are more prone to be nullified by the host neutralizing factors. To minimize such suppression of therapeutic effect, especially in terms of AAV2 and its derivatives, we introduced three serine-to-glycine mutations, based on the phosphorylation sites identified by mass spectrum analysis, to the XL32 capsid to generate a novel serotype named AAVYC5. Via intravitreal administration, AAVYC5 was transduced more effectively into multiple retinal layers compared with AAV2 and XL32. AAVYC5 also enabled successful delivery of anti-angiogenic molecules to rescue laser-induced choroidal neovascularization and astrogliosis in mice and non-human primates. Furthermore, we detected fewer neutralizing antibodies and binding IgG in human sera against AAVYC5 than those specific for AAV2 and XL32. Our results thus implicate this capsid-optimized AAVYC5 as a promising vector suitable for a wide population, particularly those with undesirable AAV2 seroreactivity.
Collapse
Affiliation(s)
- Lin-Lin Luo
- Department of Ophthalmology, Army Medical Center of PLA, Army Medical University, Chongqing, 400042, China
| | - Jie Xu
- Department of Ophthalmology, Army Medical Center of PLA, Army Medical University, Chongqing, 400042, China
| | - Bing-Qiao Wang
- Department of Neurology, The Second Affiliated Hospital, Army Medical University, Chongqing, 400042, China
| | - Chen Chen
- School of Bioengineering, East China University of Science and Technology, Shanghai, 200237, China; Belief BioMed Co., Ltd, Shanghai, China
| | - Xi Chen
- Chongqing Institute for Brain and Intelligence, Guangyang Bay Laboratory, Chongqing, 400064, China
| | - Qiu-Mei Hu
- Department of Ophthalmology, Army Medical Center of PLA, Army Medical University, Chongqing, 400042, China
| | - Yu-Qiu Wang
- School of Bioengineering, East China University of Science and Technology, Shanghai, 200237, China; Analytical Research Center for Organic and Biological Molecules, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
| | - Wan-Yun Zhang
- Department of Neurology, The Second Affiliated Hospital, Army Medical University, Chongqing, 400042, China
| | - Wan-Xiang Jiang
- Sichuan Greentech Bioscience Co,. Ltd, Bencao Avenue, New Economic Development Zone, Meishan, Sichuan, 620010, China
| | - Xin-Ting Li
- School of Bioengineering, East China University of Science and Technology, Shanghai, 200237, China
| | - Hu Zhou
- Analytical Research Center for Organic and Biological Molecules, CAS Key Laboratory of Receptor Research, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China
| | - Xiao Xiao
- School of Bioengineering, East China University of Science and Technology, Shanghai, 200237, China; Belief BioMed Co., Ltd, Shanghai, China.
| | - Kai Zhao
- School of Bioengineering, East China University of Science and Technology, Shanghai, 200237, China; Belief BioMed Co., Ltd, Shanghai, China.
| | - Sen Lin
- Department of Neurology, The Second Affiliated Hospital, Army Medical University, Chongqing, 400042, China; Chongqing Institute for Brain and Intelligence, Guangyang Bay Laboratory, Chongqing, 400064, China.
| |
Collapse
|
2
|
Danish E, Alhashem A, Aljehani R, Aljawi A, Aldarwish MM, Al Mutairi F, Alfadhel M, Alrifai MT, Alobaisi S. Phenotype and genotype of 15 Saudi patients with achromatopsia: A case series. Saudi J Ophthalmol 2023; 37:301-306. [PMID: 38155673 PMCID: PMC10752271 DOI: 10.4103/sjopt.sjopt_108_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/23/2023] [Accepted: 07/27/2023] [Indexed: 12/30/2023] Open
Abstract
PURPOSE Achromatopsia is a rare stationary retinal disorder that primarily affects the cone photoreceptors. Individuals with achromatopsia present with photophobia, nystagmus, reduced visual acuity (VA), and color blindness. Multiple genes responsible for achromatopsia have been identified (e.g. cyclic nucleotide-gated channel subunit alpha 3 [CNGA3] and activating transcription factor 6). Studies have assessed the role of gene therapy in achromatopsia. Therefore, for treatment and prevention, the identification of phenotypes and genotypes is crucial. Here, we described the clinical manifestations and genetic mutations associated with achromatopsia in patients from Saudi Arabia. METHODS This case series study included 15 patients with clinical presentations, suggestive of achromatopsia, who underwent ophthalmological and systemic evaluations. Patients with typical achromatopsia phenotype underwent genetic evaluation using whole-exome testing. RESULTS All patients had nystagmus (n = 15) and 93.3% had photophobia (n = 14). In addition, all patients (n = 15) had poor VA. Hyperopia with astigmatism was observed in 93.3% (n = 14) and complete color blindness in 93.3% of the patients (n = 14). In the context of family history, both parents of all patients (n = 15) were genetic carriers, with a high consanguinity rate (82%, n = 9 families). Electroretinography showed cone dysfunction with normal rods in 66.7% (n = 10) and both cone-rod dysfunction in 33.3% (n = 5) patients. Regarding the genotypic features, 93% of patients had variants in CNGA3 (n = 14) categorized as pathogenic Class 1 (86.7%, n = 13). Further, 66.7% (n = 10) of patients also harbored the c.661C>T DNA variant. Further, the patients were homozygous for these mutations. Three other variants were also identified: c.1768G>A (13.3%, n = 2), c.830G>A (6.6%, n = 1), and c. 822G >T (6.6%, n = 1). CONCLUSION Consanguinity and belonging to the same tribe are major risk factors for disease inheritance. The most common genotype was CNGA3 with the c.661C>T DNA variant. We recommend raising awareness among families and providing genetic counseling for this highly debilitating disease.
Collapse
Affiliation(s)
- Enam Danish
- Department of Ophthalmology, King Fahad Armed Forces Hospital, Jeddah, Saudi Arabia
| | - Amal Alhashem
- Department of Pediatric, Division of Genetic and Metabolic Medicine, Prince Sultan Medical Military City, College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Reham Aljehani
- Department of Ophthalmology, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Anan Aljawi
- Department of Ophthalmology, King Abdulaziz Medical City, Jeddah, Saudi Arabia
| | - Manar M. Aldarwish
- Department of Genetics and Precision Medicine, King Abdullah Specialized Children Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| | - Fuad Al Mutairi
- Department of Genetics and Precision Medicine, King Abdullah Specialized Children Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
- King Abdullah International Medical Research Centre, Ministry of National Guard Health Affairs, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Majid Alfadhel
- Department of Genetics and Precision Medicine, King Abdullah Specialized Children Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
- Department of Medical Genomics Research, King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Muhammad T. Alrifai
- King Abdullah International Medical Research Centre, Ministry of National Guard Health Affairs, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
- Pediatric Ophthalmology Division, Department of Pediatric Surgery, King Abdullah Specialized Children Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| | - Saif Alobaisi
- Pediatric Ophthalmology Division, Department of Pediatric Surgery, King Abdullah Specialized Children Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| |
Collapse
|
3
|
Leroy BP, Fischer MD, Flannery JG, MacLaren RE, Dalkara D, Scholl HPN, Chung DC, Spera C, Viriato D, Banhazi J. Gene Therapy for Inherited Retinal Disease: Long-Term Durability of Effect. Ophthalmic Res 2022; 66:179-196. [PMID: 36103843 DOI: 10.1159/000526317] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 07/27/2022] [Indexed: 12/23/2023]
Abstract
The recent approval of voretigene neparvovec (Luxturna®) for patients with biallelic RPE65 mutation-associated inherited retinal dystrophy with viable retinal cells represents an important step in the development of ocular gene therapies. Herein, we review studies investigating the episomal persistence of different recombinant adeno-associated virus (rAAV) vector genomes and the preclinical and clinical evidence of long-term effects of different RPE65 gene replacement therapies. A targeted review of articles published between 1974 and January 2021 in Medline®, Embase®, and other databases was conducted, followed by a descriptive longitudinal analysis of the clinical trial outcomes of voretigene neparvovec. Following an initial screening, 14 publications examining the episomal persistence of different rAAV genomes and 71 publications evaluating gene therapies in animal models were included. Viral genomes were found to persist for at least 22 months (longest study follow-up) as transcriptionally active episomes. Treatment effects lasting almost a decade were reported in canine disease models, with more pronounced effects the earlier the intervention. The clinical trial outcomes of voretigene neparvovec are consistent with preclinical findings and reveal sustained results for up to 7.5 years for the full-field light sensitivity threshold test and 5 years for the multi-luminance mobility test in the Phase I and Phase III trials, respectively. In conclusion, the therapeutic effect of voretigene neparvovec lasts for at least a decade in animal models and 7.5 years in human subjects. Since retinal cells can retain functionality over their lifetime after transduction, these effects may be expected to last even longer in patients with a sufficient number of outer retinal cells at the time of intervention.
Collapse
Affiliation(s)
- Bart P Leroy
- Department of Ophthalmology & Centre for Medical Genetics, Ghent University Hospital & Ghent University, Ghent, Belgium
- Division of Ophthalmology & Center for Cellular & Molecular Therapeutics, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - M Dominik Fischer
- University Eye Hospital, Centre for Ophthalmology, University Hospital Tübingen, Tübingen, Germany
- Oxford Eye Hospital, University of Oxford NHS Foundation Trust and NIHR Oxford Biomedical Research Centre, Oxford, UK
- Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - John G Flannery
- School of Optometry and the Helen Wills Neuroscience Institute, University of California-Berkeley, Berkeley, California, USA
| | - Robert E MacLaren
- Oxford Eye Hospital, University of Oxford NHS Foundation Trust and NIHR Oxford Biomedical Research Centre, Oxford, UK
- Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Deniz Dalkara
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France
| | - Hendrik P N Scholl
- Institute of Molecular and Clinical Ophthalmology, Basel, Switzerland
- Department of Ophthalmology, University Hospital Basel, University of Basel, Basel, Switzerland
| | | | | | | | | |
Collapse
|
4
|
Wu WH, Tsai YT, Huang IW, Cheng CH, Hsu CW, Cui X, Ryu J, Quinn PMJ, Caruso SM, Lin CS, Tsang SH. CRISPR genome surgery in a novel humanized model for autosomal dominant retinitis pigmentosa. Mol Ther 2022; 30:1407-1420. [PMID: 35150888 PMCID: PMC9077379 DOI: 10.1016/j.ymthe.2022.02.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 01/27/2022] [Accepted: 02/07/2022] [Indexed: 11/21/2022] Open
Abstract
Mutations in rhodopsin (RHO) are the most common causes of autosomal dominant retinitis pigmentosa (adRP), accounting for 20% to 30% of all cases worldwide. However, the high degree of genetic heterogeneity makes development of effective therapies cumbersome. To provide a universal solution to RHO-related adRP, we devised a CRISPR-based, mutation-independent gene ablation and replacement (AR) compound therapy carried by a dual AAV2/8 system. Moreover, we developed a novel hRHOC110R/hRHOWT humanized mouse model to assess the AR treatment in vivo. Results show that this humanized RHO mouse model exhibits progressive rod-cone degeneration that phenocopies hRHOC110R/hRHOWT patients. In vivo transduction of AR AAV8 dual vectors remarkably ablates endogenous RHO expression and overexpresses exogenous WT hRHO. Furthermore, the administration of AR during adulthood significantly hampers photoreceptor degeneration both histologically and functionally for at least 6 months compared with sole gene replacement or surgical trauma control. This study demonstrates the effectiveness of AR treatment of adRP in the human genomic context while revealing the feasibility of its application for other autosomal dominant disorders.
Collapse
Affiliation(s)
- Wen-Hsuan Wu
- Jonas Children's Vision Care and the Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia Stem Cell Initiative, Columbia University, New York, NY 10032, USA; Edward S. Harkness Eye Institute, New York-Presbyterian Hospital/Columbia University Medical Center, New York, NY 10032, USA
| | - Yi-Ting Tsai
- Department of Biomedical Engineering, Columbia University, New York, NY 10032, USA
| | - I-Wen Huang
- Jonas Children's Vision Care and the Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia Stem Cell Initiative, Columbia University, New York, NY 10032, USA; Edward S. Harkness Eye Institute, New York-Presbyterian Hospital/Columbia University Medical Center, New York, NY 10032, USA
| | - Chia-Hua Cheng
- Jonas Children's Vision Care and the Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia Stem Cell Initiative, Columbia University, New York, NY 10032, USA; Edward S. Harkness Eye Institute, New York-Presbyterian Hospital/Columbia University Medical Center, New York, NY 10032, USA
| | - Chun-Wei Hsu
- Jonas Children's Vision Care and the Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia Stem Cell Initiative, Columbia University, New York, NY 10032, USA; Edward S. Harkness Eye Institute, New York-Presbyterian Hospital/Columbia University Medical Center, New York, NY 10032, USA
| | - Xuan Cui
- Jonas Children's Vision Care and the Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia Stem Cell Initiative, Columbia University, New York, NY 10032, USA; Edward S. Harkness Eye Institute, New York-Presbyterian Hospital/Columbia University Medical Center, New York, NY 10032, USA
| | - Joseph Ryu
- Jonas Children's Vision Care and the Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia Stem Cell Initiative, Columbia University, New York, NY 10032, USA; Edward S. Harkness Eye Institute, New York-Presbyterian Hospital/Columbia University Medical Center, New York, NY 10032, USA
| | - Peter M J Quinn
- Jonas Children's Vision Care and the Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia Stem Cell Initiative, Columbia University, New York, NY 10032, USA; Edward S. Harkness Eye Institute, New York-Presbyterian Hospital/Columbia University Medical Center, New York, NY 10032, USA
| | | | - Chyuang-Sheng Lin
- Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY 10032, USA
| | - Stephen H Tsang
- Jonas Children's Vision Care and the Bernard & Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, Columbia Stem Cell Initiative, Columbia University, New York, NY 10032, USA; Edward S. Harkness Eye Institute, New York-Presbyterian Hospital/Columbia University Medical Center, New York, NY 10032, USA; Department of Biomedical Engineering, Columbia University, New York, NY 10032, USA; Department of Pathology & Cell Biology, Institute of Human Nutrition, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA.
| |
Collapse
|
5
|
Delineating the Molecular and Phenotypic Spectrum of the CNGA3-Related Cone Photoreceptor Disorder in Pakistani Families. Genes (Basel) 2022; 13:genes13040617. [PMID: 35456423 PMCID: PMC9031457 DOI: 10.3390/genes13040617] [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: 01/31/2022] [Revised: 03/10/2022] [Accepted: 03/21/2022] [Indexed: 11/17/2022] Open
Abstract
Cone photoreceptor dysfunction represents a clinically heterogenous group of disorders characterized by nystagmus, photophobia, reduced central or color vision, and macular dystrophy. Here, we described the molecular findings and clinical manifestations of achromatopsia, a partial or total absence of color vision, co-segregating with three known missense variants of CNGA3 in three large consanguineous Pakistani families. Fundus examination and optical coherence tomography (OCT) imaging revealed myopia, thin retina, retinal pigment epithelial cells loss at fovea/perifovea, and macular atrophy. Combination of Sanger and whole exome sequencing revealed three known homozygous missense variants (c.827A>G, p.(Asn276Ser); c.847C>T, p.(Arg283Trp); c.1279C>T, p.(Arg427Cys)) in CNGA3, the α-subunit of the cyclic nucleotide-gated cation channel in cone photoreceptor cells. All three variants are predicted to replace evolutionary conserved amino acids, and to be pathogenic by specific in silico programs, consistent with the observed altered membrane targeting of CNGA3 in heterologous cells. Insights from our study will facilitate counseling regarding the molecular and phenotypic landscape of CNGA3-related cone dystrophies.
Collapse
|
6
|
Michalakis S, Gerhardt M, Rudolph G, Priglinger S, Priglinger C. Achromatopsia: Genetics and Gene Therapy. Mol Diagn Ther 2022; 26:51-59. [PMID: 34860352 PMCID: PMC8766373 DOI: 10.1007/s40291-021-00565-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2021] [Indexed: 01/02/2023]
Abstract
Achromatopsia (ACHM), also known as rod monochromatism or total color blindness, is an autosomal recessively inherited retinal disorder that affects the cones of the retina, the type of photoreceptors responsible for high-acuity daylight vision. ACHM is caused by pathogenic variants in one of six cone photoreceptor-expressed genes. These mutations result in a functional loss and a slow progressive degeneration of cone photoreceptors. The loss of cone photoreceptor function manifests at birth or early in childhood and results in decreased visual acuity, lack of color discrimination, abnormal intolerance to light (photophobia), and rapid involuntary eye movement (nystagmus). Up to 90% of patients with ACHM carry mutations in CNGA3 or CNGB3, which are the genes encoding the alpha and beta subunits of the cone cyclic nucleotide-gated (CNG) channel, respectively. No authorized therapy for ACHM exists, but research activities have intensified over the past decade and have led to several preclinical gene therapy studies that have shown functional and morphological improvements in animal models of ACHM. These encouraging preclinical data helped advance multiple gene therapy programs for CNGA3- and CNGB3-linked ACHM into the clinical phase. Here, we provide an overview of the genetic and molecular basis of ACHM, summarize the gene therapy-related research activities, and provide an outlook for their clinical application.
Collapse
Affiliation(s)
- Stylianos Michalakis
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstr. 8, 80336, Munich, Germany.
| | - Maximilian Gerhardt
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstr. 8, 80336, Munich, Germany
| | - Günther Rudolph
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstr. 8, 80336, Munich, Germany
| | - Siegfried Priglinger
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstr. 8, 80336, Munich, Germany
| | - Claudia Priglinger
- Department of Ophthalmology, University Hospital, LMU Munich, Mathildenstr. 8, 80336, Munich, Germany
| |
Collapse
|
7
|
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]
|
8
|
Dai X, Jin X, Ye Q, Huang H, Duo L, Lu C, Bao J, Chen H. Intraperitoneal chromophore injections delay early-onset and rapid retinal cone degeneration in a mouse model of Leber congenital amaurosis. Exp Eye Res 2021; 212:108776. [PMID: 34582935 DOI: 10.1016/j.exer.2021.108776] [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] [Received: 05/28/2021] [Revised: 09/04/2021] [Accepted: 09/23/2021] [Indexed: 10/20/2022]
Abstract
Highly expressed in the retinal pigment epithelium (RPE), the RPE-specific 65-kDa (RPE65) enzyme is indispensable to generate 11-cis-retinal (11cRAL), a chromophore for rhodopsin and cone photopigments. RPE65 deficiency can lead to Leber congenital amaurosis type 2 (LCA2), in which the isomerization of photobleached all-trans-retinal into photosensitive 11cRAL is blocked, ultimately causing severe retinal dysfunction and degeneration. The related mouse models, which are constructed through gene knockout or caused by spontaneous mutations, morphologically present with early-onset and rapid retinal cone cells degeneration, including loss of short-wavelength-sensitive cone opsins (S-opsins) and mislocalization of medium-wavelength-sensitive cone opsins (M-opsins). Studies have shown that routine Rpe65 gene replacement therapy, mediated by an adeno-associated virus (AAV) vector, can restore RPE65 protein. However, AAV transfection and Rpe65 transgene expression require at least one to two weeks, and the treatment cannot fully block the early-onset cone degeneration. To determine the feasibility of delaying cone degeneration before gene therapy, we investigated the impact of 11cRAL treatment in an early-age LCA2 retinal degeneration 12 (rd12) mouse model. Similar to human patients, the mouse model carries a spontaneous mutation in the Rpe65 gene, which results in disrupted endogenous 11cRAL regeneration. We found that RPE65 deficiency did not notably affect rodent retinal vessels. Under red light illumination, the rd12 mice were intraperitoneally injected with exogenous 11cRAL from postnatal day (P) 14 to P21. Three days after the last injection, a notable recovery of retinal function was observed using scotopic and photopic electroretinograms. Using optical coherence tomography and histological analyses of the deficient retinas, we found changes in the thickness of the photoreceptor outer segment (OS); this change could be rescued by early 11cRAL treatment. In addition, the treatment notably preserved M- and S-opsins, both of which maintained appropriate localization inside cone cells, as shown by the wild-type mice. In contrast, the age-matched untreated rd12 mice were characterized by retinal S-opsin loss and M-opsin mislocalization from the photoreceptor OS to the inner segment, outer nuclear layer, or outer plexiform layer. Notably, 11cRAL treatment could not maintain retinal function for a long time. Ten days after the last injection, the rod and M-cone electroretinograms significantly decreased, and S-cone responses almost extinguished. Our findings suggest that early 11cRAL treatment is useful for restoring retinal function and rescuing morphology in the rd12 mouse model, and the early-onset and rapid cone degeneration can be delayed before gene therapy.
Collapse
Affiliation(s)
- Xufeng Dai
- School of Ophthalmology and Optometry, The Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; State Key Laboratory of Ophthalmology, Optometry, and Visual Science, 270 Xueyuan Road, Wenzhou, Zhejiang, 325027, China
| | - Xumin Jin
- Laboratory Animal Centre, Wenzhou Medical University, Wenzhou, Zhejiang, 325035, China
| | - Qian Ye
- State Key Laboratory of Ophthalmology, Optometry, and Visual Science, 270 Xueyuan Road, Wenzhou, Zhejiang, 325027, China
| | - Haixiao Huang
- School of Ophthalmology and Optometry, The Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China
| | - Lan Duo
- School of Ophthalmology and Optometry, The Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; State Key Laboratory of Ophthalmology, Optometry, and Visual Science, 270 Xueyuan Road, Wenzhou, Zhejiang, 325027, China
| | - Chunjie Lu
- School of Ophthalmology and Optometry, The Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China
| | - Jinhua Bao
- School of Ophthalmology and Optometry, The Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; State Key Laboratory of Ophthalmology, Optometry, and Visual Science, 270 Xueyuan Road, Wenzhou, Zhejiang, 325027, China.
| | - Hao Chen
- School of Ophthalmology and Optometry, The Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; State Key Laboratory of Ophthalmology, Optometry, and Visual Science, 270 Xueyuan Road, Wenzhou, Zhejiang, 325027, China.
| |
Collapse
|
9
|
El Moussawi Z, Boueiri M, Al-Haddad C. Gene therapy in color vision deficiency: a review. Int Ophthalmol 2021; 41:1917-1927. [PMID: 33528822 DOI: 10.1007/s10792-021-01717-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 01/09/2021] [Indexed: 11/24/2022]
Abstract
BACKGROUND Color vision deficiencies are a group of vision disorders, characterized by abnormal color discrimination. They include red-green color blindness, yellow-blue color blindness and achromatopsia, among others. The deficiencies are caused by mutations in the genes coding for various components of retinal cones. Gene therapy is rising as a promising therapeutic modality. The purpose of this review article is to explore the available literature on gene therapy in the different forms of color vision deficiencies. METHODS A thorough literature review was performed on PubMed using the keywords: color vision deficiencies, gene therapy, achromatopsia and the various genes responsible for this condition (OPN1LW, OPN1MW, ATF6, CNGA3, CNGB3, GNAT2, PDE6H, and PDE6C). RESULTS Various adenovirus vectors have been deployed to test the efficacy of gene therapy for achromatopsia in animals and humans. Gene therapy trials in humans and animals targeting mutations in CNGA3 have been performed, demonstrating an improvement in electroretinogram (ERG)-investigated cone cell functionality. Similar outcomes have been reported for experimental studies on other genes (CNGB3, GNAT2, M- and L-opsin). It has also been reported that delivering the genes via intravitreal rather than subretinal injections could be safer. There are currently 3 ongoing human clinical trials for the treatment of achromatopsia due to mutations in CNGB3 and CNGA3. CONCLUSION Experimental studies and clinical trials generally showed improvement in ERG-investigated cone cell functionality and visually elicited behavior. Gene therapy is a promising novel therapeutic modality in color vision deficiencies.
Collapse
Affiliation(s)
- Zeinab El Moussawi
- Ophthalmology Department, American University of Beirut, Beirut, Lebanon
| | - Marguerita Boueiri
- Faculty of Medicine, Medical School, American University of Beirut, Beirut, Lebanon
| | | |
Collapse
|
10
|
Abstract
Color is a fundamental aspect of normal visual experience. This chapter provides an overview of the role of color in human behavior, a survey of current knowledge regarding the genetic, retinal, and neural mechanisms that enable color vision, and a review of inherited and acquired defects of color vision including a discussion of diagnostic tests.
Collapse
Affiliation(s)
- Joseph Carroll
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, United States.
| | - Bevil R Conway
- Laboratory of Sensorimotor Research, National Eye Institute, National Institute of Mental Health, Bethesda, MD, United States.
| |
Collapse
|
11
|
Abstract
Retinal degenerative diseases caused by photoreceptor cell death are major causes of irreversible vision loss. As only primates have a macula, the nonhuman primate (NHP) models have a crucial role not only in revealing biological mechanisms underlying high-acuity vision but also in the development of therapies. Successful translation of basic research findings into clinical trials and, moreover, approval of the first therapies for blinding inherited and age-related retinal dystrophies has been reported in recent years. This article explores the value of the NHP models in understanding human vision and reviews their contribution to the development of innovative therapeutic strategies to save and restore vision.
Collapse
|
12
|
Moshiri A, Chen R, Kim S, Harris RA, Li Y, Raveendran M, Davis S, Liang Q, Pomerantz O, Wang J, Garzel L, Cameron A, Yiu G, Stout JT, Huang Y, Murphy CJ, Roberts J, Gopalakrishna KN, Boyd K, Artemyev NO, Rogers J, Thomasy SM. A nonhuman primate model of inherited retinal disease. J Clin Invest 2019; 129:863-874. [PMID: 30667376 PMCID: PMC6355306 DOI: 10.1172/jci123980] [Citation(s) in RCA: 62] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 11/15/2018] [Indexed: 12/30/2022] Open
Abstract
Inherited retinal degenerations are a common cause of untreatable blindness worldwide, with retinitis pigmentosa and cone dystrophy affecting approximately 1 in 3500 and 1 in 10,000 individuals, respectively. A major limitation to the development of effective therapies is the lack of availability of animal models that fully replicate the human condition. Particularly for cone disorders, rodent, canine, and feline models with no true macula have substantive limitations. By contrast, the cone-rich macula of a nonhuman primate (NHP) closely mirrors that of the human retina. Consequently, well-defined NHP models of heritable retinal diseases, particularly cone disorders that are predictive of human conditions, are necessary to more efficiently advance new therapies for patients. We have identified 4 related NHPs at the California National Primate Research Center with visual impairment and findings from clinical ophthalmic examination, advanced retinal imaging, and electrophysiology consistent with achromatopsia. Genetic sequencing confirmed a homozygous R565Q missense mutation in the catalytic domain of PDE6C, a cone-specific phototransduction enzyme associated with achromatopsia in humans. Biochemical studies demonstrate that the mutant mRNA is translated into a stable protein that displays normal cellular localization but is unable to hydrolyze cyclic GMP (cGMP). This NHP model of a cone disorder will not only serve as a therapeutic testing ground for achromatopsia gene replacement, but also for optimization of gene editing in the macula and of cone cell replacement in general.
Collapse
Affiliation(s)
- Ala Moshiri
- Department of Ophthalmology & Vision Science, School of Medicine, UC Davis, Sacramento, California, USA
| | - Rui Chen
- Human Genome Sequencing Center and Department of Molecular and Human Genetics, and.,Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Soohyun Kim
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA
| | - R Alan Harris
- Human Genome Sequencing Center and Department of Molecular and Human Genetics, and
| | - Yumei Li
- Human Genome Sequencing Center and Department of Molecular and Human Genetics, and
| | | | - Sarah Davis
- California National Primate Research Center, Davis, California, USA
| | - Qingnan Liang
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Ori Pomerantz
- California National Primate Research Center, Davis, California, USA
| | - Jun Wang
- Human Genome Sequencing Center and Department of Molecular and Human Genetics, and
| | - Laura Garzel
- California National Primate Research Center, Davis, California, USA
| | - Ashley Cameron
- California National Primate Research Center, Davis, California, USA
| | - Glenn Yiu
- Department of Ophthalmology & Vision Science, School of Medicine, UC Davis, Sacramento, California, USA
| | - J Timothy Stout
- Department of Ophthalmology, Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA
| | | | - Christopher J Murphy
- Department of Ophthalmology & Vision Science, School of Medicine, UC Davis, Sacramento, California, USA.,Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.,EyeKor Inc., Madison, Wisconsin, USA
| | - Jeffrey Roberts
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA.,California National Primate Research Center, Davis, California, USA
| | | | - Kimberly Boyd
- Department of Molecular Physiology and Biophysics, and
| | - Nikolai O Artemyev
- Department of Molecular Physiology and Biophysics, and.,Department of Ophthalmology and Visual Sciences, The University of Iowa Carver College of Medicine, Iowa City, Iowa, USA
| | - Jeffrey Rogers
- Human Genome Sequencing Center and Department of Molecular and Human Genetics, and
| | - Sara M Thomasy
- Department of Ophthalmology & Vision Science, School of Medicine, UC Davis, Sacramento, California, USA.,Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California-Davis, Davis, California, USA
| |
Collapse
|
13
|
Ofri R, Averbukh E, Ezra-Elia R, Ross M, Honig H, Obolensky A, Rosov A, Hauswirth WW, Gootwine E, Banin E. Six Years and Counting: Restoration of Photopic Retinal Function and Visual Behavior Following Gene Augmentation Therapy in a Sheep Model of CNGA3 Achromatopsia. Hum Gene Ther 2018; 29:1376-1386. [PMID: 29926749 DOI: 10.1089/hum.2018.076] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Achromatopsia causes severely reduced visual acuity, photoaversion, and inability to discern colors due to cone photoreceptor dysfunction. In 2010, we reported on day-blindness in sheep caused by a stop-codon mutation of the ovine CNGA3 gene and began gene augmentation therapy trials in this naturally occurring large animal model of CNGA3 achromatopsia. The purpose of this study was to evaluate long-term efficacy and safety results of treatment, findings that hold great relevance for clinical trials that started recently in CNGA3 achromatopsia patients. Nine day-blind sheep were available for long-term follow up. The right eye of each sheep was treated with a single subretinal injection of an Adeno-Associated Virus Type 5 (AAV5) vector carrying either a mouse (n = 4) or a human (n = 5) CNGA3 transgene under control of the 2.1-Kb red/green opsin promoter. The efficacy of treatment was assessed periodically with photopic maze tests and electroretinographic (ERG) recordings for as long as 74 months postoperatively. Safety was assessed by repeated ophthalmic examinations and scotopic ERG recordings. The retinas of three animals that died of unrelated causes >5 years post-treatment were studied histologically and immunohistochemically using anti-hCNGA3 and anti-red/green cone opsin antibodies. Passage time and number of collisions of treated sheep in the photopic maze test were significantly lower at all follow-up examinations as compared with pretreatment values (p = 0.0025 and p < 0.001, respectively). ERG Critical Flicker Fusion Frequency and flicker amplitudes at 30 and 40 Hz showed significant improvement following treatment (p < 0.0001) throughout the study. Ophthalmic examinations and rod ERG recordings showed no abnormalities in the treated eyes. Immunohistochemistry revealed the presence of CNGA3 protein in red/green opsin-positive cells (cones) of the treated eyes. Our results show significant, long-term improvement in cone function, demonstrating a robust rescue effect up to six years following a single treatment with a viral vector that provides episomal delivery of the transgene. This unique follow-up duration confirms the safe and stable nature of AAV5 gene therapy in the ovine achromatopsia model.
Collapse
Affiliation(s)
- Ron Ofri
- Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Edward Averbukh
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Raaya Ezra-Elia
- Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Maya Ross
- Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Hen Honig
- Agricultural Research Organization, The Volcani Center, Beit Dagan, Israel
| | - Alexey Obolensky
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Alexander Rosov
- Agricultural Research Organization, The Volcani Center, Beit Dagan, Israel
| | | | - Elisha Gootwine
- Agricultural Research Organization, The Volcani Center, Beit Dagan, Israel
| | - Eyal Banin
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| |
Collapse
|
14
|
Dai X, Pang S, Wang J, FitzMaurice B, Pang J, Chang B. Photoreceptor degeneration in a new Cacna1f mutant mouse model. Exp Eye Res 2018; 179:106-114. [PMID: 30445045 DOI: 10.1016/j.exer.2018.11.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Revised: 10/17/2018] [Accepted: 11/12/2018] [Indexed: 02/06/2023]
Abstract
The Cacna1f gene encodes the α1F subunit of an L-type voltage-gated calcium channel, Cav1.4. In photoreceptor synaptic terminals, Cav1.4 channels mediate glutamate release and postsynaptic responses associated with visual signal transmission. We have discovered a new Cacna1f mutation in nob9 mice, which display more severe phenotypes than do nob2 mice. To characterize the nob9 phenotype at different ages, we examined the murine fundus, applied retinal optical coherence tomography, measured flash electroretinograms (ERGs) in vivo, and analyzed the retinal histology in vitro. After identifying the X-linked recessive inheritance trait, we sequenced Cacna1f as the candidate gene. Mutations in this gene were detected by polymerase chain reaction (PCR) and confirmed by restriction fragment length polymorphism. Morphologically, an early-onset of retinal disorder was detected, and the degeneration of the outer plexiform layers progressed rapidly. Moreover, the mutant mice showed drastically reduced scotopic ERGs with increasing age. In 14-month-old nob9 retinas, immunostaining of cone opsins demonstrated a reduction in the number of short-wavelength opsins (S-opsins) to 54% of wild-type levels, and almost no middle-wavelength opsins (M-opsins) were observed. No cone ERGs could be detected from residual cones, in which S-opsins abnormally migrated to inner segments of the photoreceptors. The mutations of the Cacna1f gene in nob9 mice involved both a single nucleotide G to A transition and a 10-nucleotide insertion, the latter resulting in a frame-shift mutation in exon 14.
Collapse
Affiliation(s)
- Xufeng Dai
- School of Ophthalmology and Optometry, The Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; Department of Ophthalmology, University of Florida, Gainesville, FL, 32610, USA
| | - Shiyi Pang
- The Jackson Laboratory, Bar Harbor, ME, 04609, USA; College of Medicine, University of Florida, Gainesville, FL, 32610, USA
| | - Jieping Wang
- The Jackson Laboratory, Bar Harbor, ME, 04609, USA
| | | | - Jijing Pang
- School of Ophthalmology and Optometry, The Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, 325027, China; Department of Ophthalmology, University of Florida, Gainesville, FL, 32610, USA; College of Medicine, University of Florida, Gainesville, FL, 32610, USA; Eye Research Institute, Xiamen Eye Center of Xiamen University, Xiamen, 361001, China.
| | - Bo Chang
- The Jackson Laboratory, Bar Harbor, ME, 04609, USA.
| |
Collapse
|
15
|
Abstract
The first step in vision is the absorption of photons by the photopigments in cone and rod photoreceptors. After initial amplification within the phototransduction cascade the signal is translated into an electrical signal by the action of cyclic nucleotide-gated (CNG) channels. CNG channels are ligand-gated ion channels that are activated by the binding of cyclic guanosine monophosphate (cGMP) or cyclic adenosine monophosphate (cAMP). Retinal CNG channels transduce changes in intracellular concentrations of cGMP into changes of the membrane potential and the Ca2+ concentration. Structurally, the CNG channels belong to the superfamily of pore-loop cation channels and share a common gross structure with hyperpolarization-activated cyclic nucleotide-gated (HCN) channels and voltage-gated potassium channels (KCN). In this review, we provide an overview on the molecular properties of CNG channels and describe their physiological role in the phototransduction pathways. We also discuss insights into the pathophysiological role of CNG channel proteins that have emerged from the analysis of CNG channel-deficient animal models and human CNG channelopathies. Finally, we summarize recent gene therapy activities and provide an outlook for future clinical application.
Collapse
Affiliation(s)
- Stylianos Michalakis
- Center for Integrated Protein Science Munich (CIPSM), Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr, 5-13, 81377 Munich, Germany.
| | - Elvir Becirovic
- Center for Integrated Protein Science Munich (CIPSM), Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr, 5-13, 81377 Munich, Germany.
| | - Martin Biel
- Center for Integrated Protein Science Munich (CIPSM), Department of Pharmacy-Center for Drug Research, Ludwig-Maximilians-Universität München, Butenandtstr, 5-13, 81377 Munich, Germany.
| |
Collapse
|