1
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Zhang M, Lima E Silva R, Zhou L, Hackett SF, Campochiaro PA, Shen J. Improved protocol for histological and histopathological preparation of large eyes. Microsc Res Tech 2024. [PMID: 39237471 DOI: 10.1002/jemt.24698] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Revised: 08/06/2024] [Accepted: 08/27/2024] [Indexed: 09/07/2024]
Abstract
The development of new treatments for ocular diseases often requires investigating eyes similar in size and structure to human eyes. Such studies are challenging because analyzing the histopathology of large, human-sized eyes can be technically difficult. In particular, obtaining high-quality frozen sections is almost impossible due to the formation of ice crystals in the vitreous, which causes crush artifacts during the procedures of section and post sectioning manipulations. Herein, we describe a new method that provides high-quality frozen sections for large eyes and demonstrate its usefulness in the eyes of rabbits, pigs, minipigs, monkeys, and humans. We observed that artifactual separation of the photoreceptors from the retinal pigment epithelium is minimized and photoreceptor morphology is preserved. This method can be highly beneficial for investigators seeking to translate new treatments for ocular disease into the clinic. RESEARCH HIGHLIGHTS: Histopathological analysis of large and human-sized eyes presents significant challenges, particularly in obtaining high-quality frozen sections. A multistep fixation followed by vitreous removal and replacement ensures better cryopreservation and embedding of large eyes, minimizing the morphological and structural retinal loss found in many studies. Our results demonstrate that a multistep fixation and cryopreservation method for large eyes in histopathology consistently minimizes the artifactual separation of photoreceptors from the retinal pigment epithelium, thereby preserving photoreceptor morphology and providing high-quality frozen sections. A new method providing high-quality sections is necessary and will be highly useful for investigators aiming to translate new treatments for ocular diseases into clinical applications.
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Affiliation(s)
- Mingliang Zhang
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Tianjin Key Laboratory of Retinal Functions and Diseases, Tianjin Branch of National Clinical Research Center for Ocular Disease, Eye Institute and School of Optometry, Tianjin Medical University Eye Hospital, Tianjin, China
| | - Raquel Lima E Silva
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Lingli Zhou
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Sean F Hackett
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Peter A Campochiaro
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
- Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jikui Shen
- Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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2
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Willimann M, Tiyaboonchai A, Adachi K, Li B, Waldburger L, Nakai H, Grompe M, Thöny B. AAV Capsid Screening for Translational Pig Research Using a Mouse Xenograft Liver Model. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.29.596409. [PMID: 38853940 PMCID: PMC11160762 DOI: 10.1101/2024.05.29.596409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
In gene therapy, delivery vectors are a key component for successful gene delivery and safety, based on which adeno-associated viruses (AAVs) gained popularity in particular for the liver, but also for other organs. Traditionally, rodents have been used as animal models to develop and optimize treatments, but species and organ specific tropism of AAV desire large animal models more closely related to humans for preclinical in-depth studies. Relevant AAV variants with the potential for clinical translation in liver gene therapy were previously evolved in vivo in a xenogeneic mouse model transplanted with human hepatocytes. Here, we selected and evaluated efficient AAV capsids using chimeric mice with a >90% xenografted pig hepatocytes. The pig is a valuable preclinical model for therapy studies due to its anatomic and immunological similarities to humans. Using a DNA-barcoded recombinant AAV library containing 47 different capsids and subsequent Illumina sequencing of barcodes in the AAV vector genome DNA and transcripts in the porcine hepatocytes, we found the AAVLK03 and AAVrh20 capsid to be the most efficient delivery vectors regarding transgene expression in porcine hepatocytes. In attempting to validate these findings with primary porcine hepatocytes, we observed capsid-specific differences in cell entry and transgene expression efficiency where the AAV2, AAVAnc80, and AAVDJ capsids showed superior efficiency to AAVLK03 and AAVrh20. This work highlights intricacies of in vitro testing with primary hepatocytes and the requirements for suitable pre-clinical animal models but suggests the chimeric mouse to be a valuable model to predict AAV capsids to transduce porcine hepatocytes efficiently.
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Affiliation(s)
- Melanie Willimann
- University Children's Hospital Zurich, Division of Metabolism and Children's Research Center, Zurich, Switzerland
| | - Amita Tiyaboonchai
- Oregon Health & Science University, Stem Cell Center, Portland, Oregon, USA
| | - Kei Adachi
- Oregon Health & Science University, Department of Molecular & Medical Genetics, Portland, Oregon, USA
| | - Bin Li
- Oregon Health & Science University, Stem Cell Center, Portland, Oregon, USA
| | - Lea Waldburger
- University Children's Hospital Zurich, Division of Metabolism and Children's Research Center, Zurich, Switzerland
| | - Hiroyuki Nakai
- Oregon Health & Science University, Department of Molecular & Medical Genetics, Portland, Oregon, USA
| | - Markus Grompe
- Oregon Health & Science University, Stem Cell Center, Portland, Oregon, USA
| | - Beat Thöny
- University Children's Hospital Zurich, Division of Metabolism and Children's Research Center, Zurich, Switzerland
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3
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Gilmore WB, Hultgren NW, Chadha A, Barocio SB, Zhang J, Kutsyr O, Flores-Bellver M, Canto-Soler MV, Williams DS. Expression of two major isoforms of MYO7A in the retina: Considerations for gene therapy of Usher syndrome type 1B. Vision Res 2023; 212:108311. [PMID: 37586294 PMCID: PMC10984346 DOI: 10.1016/j.visres.2023.108311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 07/25/2023] [Accepted: 07/28/2023] [Indexed: 08/18/2023]
Abstract
Usher syndrome type 1B (USH1B) is a deaf-blindness disorder, caused by mutations in the MYO7A gene, which encodes the heavy chain of an unconventional actin-based motor protein. Here, we examined the two retinal isoforms of MYO7A, IF1 and IF2. We compared 3D models of the two isoforms and noted that the 38-amino acid region that is present in IF1 but absent from IF2 affects the C lobe of the FERM1 domain and the opening of a cleft in this potentially important protein binding domain. Expression of each of the two isoforms of human MYO7A and pig and mouse Myo7a was detected in the RPE and neural retina. Quantification by qPCR showed that the expression of IF2 was typically ∼ 7-fold greater than that of IF1. We discuss the implications of these findings for any USH1B gene therapy strategy. Given the current incomplete knowledge of the functions of each isoform, both isoforms should be considered for targeting both the RPE and the neural retina in gene augmentation therapies.
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Affiliation(s)
- W Blake Gilmore
- Department of Ophthalmology and Stein Eye Institute, Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Nan W Hultgren
- Department of Ophthalmology and Stein Eye Institute, Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Abhishek Chadha
- Department of Ophthalmology and Stein Eye Institute, Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Sonia B Barocio
- Department of Ophthalmology and Stein Eye Institute, Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Joyce Zhang
- Department of Ophthalmology and Stein Eye Institute, Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Oksana Kutsyr
- CellSight Ocular Stem Cell and Regeneration Research Program, Department of Ophthalmology, Sue Anschutz-Rodgers Eye Center, University of Colorado, School of Medicine, Aurora, CO, USA
| | - Miguel Flores-Bellver
- CellSight Ocular Stem Cell and Regeneration Research Program, Department of Ophthalmology, Sue Anschutz-Rodgers Eye Center, University of Colorado, School of Medicine, Aurora, CO, USA
| | - M Valeria Canto-Soler
- CellSight Ocular Stem Cell and Regeneration Research Program, Department of Ophthalmology, Sue Anschutz-Rodgers Eye Center, University of Colorado, School of Medicine, Aurora, CO, USA
| | - David S Williams
- Department of Ophthalmology and Stein Eye Institute, Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA.
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4
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Riedmayr LM, Hinrichsmeyer KS, Thalhammer SB, Mittas DM, Karguth N, Otify DY, Böhm S, Weber VJ, Bartoschek MD, Splith V, Brümmer M, Ferreira R, Boon N, Wögenstein GM, Grimm C, Wijnholds J, Mehlfeld V, Michalakis S, Fenske S, Biel M, Becirovic E. mRNA trans-splicing dual AAV vectors for (epi)genome editing and gene therapy. Nat Commun 2023; 14:6578. [PMID: 37852949 PMCID: PMC10584818 DOI: 10.1038/s41467-023-42386-0] [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: 08/17/2022] [Accepted: 10/10/2023] [Indexed: 10/20/2023] Open
Abstract
Large genes including several CRISPR-Cas modules like gene activators (CRISPRa) require dual adeno-associated viral (AAV) vectors for an efficient in vivo delivery and expression. Current dual AAV vector approaches have important limitations, e.g., low reconstitution efficiency, production of alien proteins, or low flexibility in split site selection. Here, we present a dual AAV vector technology based on reconstitution via mRNA trans-splicing (REVeRT). REVeRT is flexible in split site selection and can efficiently reconstitute different split genes in numerous in vitro models, in human organoids, and in vivo. Furthermore, REVeRT can functionally reconstitute a CRISPRa module targeting genes in various mouse tissues and organs in single or multiplexed approaches upon different routes of administration. Finally, REVeRT enabled the reconstitution of full-length ABCA4 after intravitreal injection in a mouse model of Stargardt disease. Due to its flexibility and efficiency REVeRT harbors great potential for basic research and clinical applications.
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Affiliation(s)
- Lisa Maria Riedmayr
- Department of Pharmacy - Center for Drug Research, LMU Munich, Munich, 81377, Germany
| | | | | | - David Manuel Mittas
- Department of Pharmacy - Center for Drug Research, LMU Munich, Munich, 81377, Germany
| | - Nina Karguth
- Department of Pharmacy - Center for Drug Research, LMU Munich, Munich, 81377, Germany
| | - Dina Yehia Otify
- Department of Pharmacy - Center for Drug Research, LMU Munich, Munich, 81377, Germany
| | | | - Valentin Johannes Weber
- Laboratory for Retinal Gene Therapy, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Schlieren, 8952, Switzerland
| | | | | | - Manuela Brümmer
- Department of Pharmacy - Center for Drug Research, LMU Munich, Munich, 81377, Germany
| | - Raphael Ferreira
- Genetics Department, Harvard Medical School, Boston, MA, 02115, USA
| | - Nanda Boon
- Department of Ophthalmology, Leiden University Medical Center (LUMC), 2333 ZA, Leiden, Netherlands
| | - Gabriele Maria Wögenstein
- Laboratory for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Schlieren, 8952, Switzerland
| | - Christian Grimm
- Laboratory for Retinal Cell Biology, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Schlieren, 8952, Switzerland
| | - Jan Wijnholds
- Department of Ophthalmology, Leiden University Medical Center (LUMC), 2333 ZA, Leiden, Netherlands
- Netherlands Institute for Neuroscience, Institute of the Royal Netherlands Academy of Arts and Sciences (KNAW), 1105 BA, Amsterdam, Netherlands
| | - Verena Mehlfeld
- Department of Pharmacy - Center for Drug Research, LMU Munich, Munich, 81377, Germany
| | - Stylianos Michalakis
- Department of Ophthalmology, University Hospital, LMU Munich, 80336, Munich, Germany
| | - Stefanie Fenske
- Department of Pharmacy - Center for Drug Research, LMU Munich, Munich, 81377, Germany
- German Center for Cardiovascular Research (DZHK), partner site Munich Heart Alliance, Munich, 81377, Germany
| | - Martin Biel
- Department of Pharmacy - Center for Drug Research, LMU Munich, Munich, 81377, Germany
| | - Elvir Becirovic
- Laboratory for Retinal Gene Therapy, Department of Ophthalmology, University Hospital Zurich, University of Zurich, Schlieren, 8952, Switzerland.
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5
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Wang L, Shah SM, Mangwani-Mordani S, Gregori NZ. Updates on Emerging Interventions for Autosomal Recessive ABCA4-Associated Stargardt Disease. J Clin Med 2023; 12:6229. [PMID: 37834872 PMCID: PMC10573680 DOI: 10.3390/jcm12196229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 09/25/2023] [Accepted: 09/25/2023] [Indexed: 10/15/2023] Open
Abstract
Autosomal recessive Stargardt disease (STGD1) is an inherited retinal degenerative disease associated with a mutated ATP-binding cassette, subfamily A, member 4 (ABCA4) gene. STGD1 is the most common form of juvenile macular degeneration with onset in late childhood to early or middle adulthood and causes progressive, irreversible visual impairment and blindness. No effective treatment is currently available. In the present article, we review the most recent updates in clinical trials targeting the management of STGD1, including gene therapy, small molecule therapy, and stem cell therapy. In gene therapy, dual adeno-associated virus and non-viral vectors have been successful in delivering the human ABCA4 gene in preclinical studies. For pharmaceutical therapies ALK-001, deuterated vitamin A shows promise with preliminary data for phase 2 trial, demonstrating a decreased atrophy growth rate after two years. Stem cell therapy using human pluripotent stem cell-derived retinal pigment epithelium cells demonstrated long-term safety three years after implantation and visual acuity improvements in the first two years after initiation of therapy. Many other treatment options have ongoing investigations and clinical trials. While multiple potential interventions have shown promise in attenuating disease progression, further exploration is necessary to demonstrate treatment safety and efficacy.
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Affiliation(s)
- Liang Wang
- University of Miami Miller School of Medicine, Miami, FL 33136, USA; (L.W.); (S.M.S.)
| | - Serena M. Shah
- University of Miami Miller School of Medicine, Miami, FL 33136, USA; (L.W.); (S.M.S.)
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL 33136, USA;
| | - Simran Mangwani-Mordani
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL 33136, USA;
| | - Ninel Z. Gregori
- Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, FL 33136, USA;
- Miami Veterans Administration Medical Center, Miami, FL 33125, USA
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6
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Toms M, Toualbi L, Almeida PV, Harbottle R, Moosajee M. Successful large gene augmentation of USH2A with non-viral episomal vectors. Mol Ther 2023; 31:2755-2766. [PMID: 37337429 PMCID: PMC10491995 DOI: 10.1016/j.ymthe.2023.06.012] [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: 01/05/2023] [Revised: 05/09/2023] [Accepted: 06/14/2023] [Indexed: 06/21/2023] Open
Abstract
USH2A mutations are a common cause of autosomal recessive retinitis pigmentosa (RP) and Usher syndrome, for which there are currently no approved treatments. Gene augmentation is a valuable therapeutic strategy for treating many inherited retinal diseases; however, conventional adeno-associated virus (AAV) gene therapy cannot accommodate cDNAs exceeding 4.7 kb, such as the 15.6-kb-long USH2A coding sequence. In the present study, we adopted an alternative strategy to successfully generate scaffold/matrix attachment region (S/MAR) DNA plasmid vectors containing the full-length human USH2A coding sequence, a GFP reporter gene, and a ubiquitous promoter (CMV or CAG), reaching a size of approximately 23 kb. We assessed the vectors in transfected HEK293 cells and USH2A patient-derived dermal fibroblasts in addition to ush2au507 zebrafish microinjected with the vector at the one-cell stage. pS/MAR-USH2A vectors drove persistent transgene expression in patient fibroblasts with restoration of usherin. Twelve months of GFP expression was detected in the photoreceptor cells, with rescue of Usher 2 complex localization in the photoreceptors of ush2au507 zebrafish retinas injected with pS/MAR-USH2A. To our knowledge, this is the first reported vector that can be used to express full-length usherin with functional rescue. S/MAR DNA vectors have shown promise as a novel non-viral retinal gene therapy, warranting further translational development.
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Affiliation(s)
- Maria Toms
- Development, Ageing, and Disease, UCL Institute of Ophthalmology, London EC1V 9EL, UK; Ocular Genomics and Therapeutics, The Francis Crick Institute, London NW1 1AT, UK
| | - Lyes Toualbi
- Development, Ageing, and Disease, UCL Institute of Ophthalmology, London EC1V 9EL, UK; Ocular Genomics and Therapeutics, The Francis Crick Institute, London NW1 1AT, UK
| | - Patrick V Almeida
- DNA Vector Research, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Richard Harbottle
- DNA Vector Research, German Cancer Research Center (DKFZ), 69120 Heidelberg, Germany
| | - Mariya Moosajee
- Development, Ageing, and Disease, UCL Institute of Ophthalmology, London EC1V 9EL, UK; Ocular Genomics and Therapeutics, The Francis Crick Institute, London NW1 1AT, UK; Department of Genetics, Moorfields Eye Hospital, NHS Foundation Trust, London EC1V 2PD, UK.
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7
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Albini S, Palmieri L, Dubois A, Bourg N, Lostal W, Richard I. Assessment of Therapeutic Potential of a Dual AAV Approach for Duchenne Muscular Dystrophy. Int J Mol Sci 2023; 24:11421. [PMID: 37511179 PMCID: PMC10380683 DOI: 10.3390/ijms241411421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 06/27/2023] [Accepted: 06/30/2023] [Indexed: 07/30/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a yet incurable rare genetic disease that affects the skeletal and cardiac muscles, leading to progressive muscle wasting and premature death. DMD is caused by the lack of dystrophin, a muscle protein essential for the biochemical support and integrity of muscle fibers. Gene replacement strategies for Duchenne muscular dystrophy (DMD) employing the adeno-associated virus (AAV) face the challenge imposed by the limited packaging capacity of AAV, only allowing the accommodation of a short version of dystrophin (µDys) that is still far removed from correcting human disease. The need to develop strategies leading to the expression of a best performing dystrophin variant led to only few studies reporting on the use of dual vectors, but none reported on a method to assess in vivo transgene reconstitution efficiency, the degree of which directly affects the use of safe AAV dosing. We report here on the generation of a dual AAV vector approach for the expression of a larger dystrophin version (quasidystrophin) based on homologous recombination, and the development of a methodology employing a strategic droplet digital PCR design, to determine the recombination efficiency as well as the occurrence of unwanted concatemerization events or aberrant expression from the single vectors. We demonstrated that, upon systemic delivery in the dystrophic D2.B10-Dmdmdx/J (DBA2mdx) mice, our dual AAV approach led to high transgene reconstitution efficiency and negligible Inverted Terminal Repeats (ITR)-dependent concatemerization, with consequent remarkable protein restoration in muscles and improvement of muscle pathology. This evidence supports the suitability of our system for gene therapy application and the potential of this methodology to assess and improve the feasibility for therapeutic translation of multiple vector approaches.
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Affiliation(s)
- Sonia Albini
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - Laura Palmieri
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - Auriane Dubois
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - Nathalie Bourg
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - William Lostal
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - Isabelle Richard
- Genethon, 91100 Evry, France
- Université Paris-Saclay, Univ Evry, Inserm, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
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8
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Ferreira MV, Fernandes S, Almeida AI, Neto S, Mendes JP, Silva RJS, Peixoto C, Coroadinha AS. Extending AAV Packaging Cargo through Dual Co-Transduction: Efficient Protein Trans-Splicing at Low Vector Doses. Int J Mol Sci 2023; 24:10524. [PMID: 37445701 DOI: 10.3390/ijms241310524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 06/16/2023] [Accepted: 06/19/2023] [Indexed: 07/15/2023] Open
Abstract
Adeno-associated viral (AAV) vectors represent one of the leading platforms for gene delivery. Nevertheless, their small packaging capacity restricts their use for diseases requiring large-gene delivery. To overcome this, dual-AAV vector systems that rely on protein trans-splicing were developed, with the split-intein Npu DnaE among the most-used. However, the reconstitution efficiency of Npu DnaE is still insufficient, requiring higher vector doses. In this work, two split-inteins, Cfa and Gp41-1, with reportedly superior trans-splicing were evaluated in comparison with Npu DnaE by transient transfections and dual-AAV in vitro co-transductions. Both Cfa and Gp41-1 split-inteins enabled reconstitution rates that were over two-fold higher than Npu DnaE and 100% of protein reconstitution. The impact of different vector preparation qualities in split-intein performances was also evaluated in co-transduction assays. Higher-quality preparations increased split-inteins' performances by three-fold when compared to low-quality preparations (60-75% vs. 20-30% full particles, respectively). Low-quality vector preparations were observed to limit split-gene reconstitutions by inhibiting co-transduction. We show that combining superior split-inteins with higher-quality vector preparations allowed vector doses to be decreased while maintaining high trans-splicing rates. These results show the potential of more-efficient protein-trans-splicing strategies in dual-AAV vector co-transduction, allowing the extension of its use to the delivery of larger therapeutic genes.
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Affiliation(s)
- Mariana V Ferreira
- iBET-Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Sofia Fernandes
- iBET-Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Ana Isabel Almeida
- iBET-Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Salomé Neto
- iBET-Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - João P Mendes
- iBET-Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Ricardo J S Silva
- iBET-Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Cristina Peixoto
- iBET-Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
| | - Ana Sofia Coroadinha
- iBET-Instituto de Biologia Experimental e Tecnológica, Apartado 12, 2781-901 Oeiras, Portugal
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa, Av. da República, 2780-157 Oeiras, Portugal
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9
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Barone F, Amaral J, Bunea I, Farnoodian M, Gupta R, Gupta R, Baker D, Phillips MJ, Blanch RJ, Maminishkis A, Gamm DM, Bharti K. A versatile laser-induced porcine model of outer retinal and choroidal degeneration for preclinical testing. JCI Insight 2023; 8:157654. [PMID: 37288665 PMCID: PMC10393234 DOI: 10.1172/jci.insight.157654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Accepted: 05/03/2023] [Indexed: 06/09/2023] Open
Abstract
Over 30 million people worldwide suffer from untreatable vision loss and blindness associated with childhood-onset and age-related eye diseases caused by photoreceptor (PR), retinal pigment epithelium (RPE), and choriocapillaris (CC) degeneration. Recent work suggests that RPE-based cell therapy may slow down vision loss in late stages of age-related macular degeneration (AMD), a polygenic disease induced by RPE atrophy. However, accelerated development of effective cell therapies is hampered by the lack of large-animal models that allow testing safety and efficacy of clinical doses covering the human macula (20 mm2). We developed a versatile pig model to mimic different types and stages of retinal degeneration. Using an adjustable power micropulse laser, we generated varying degrees of RPE, PR, and CC damage and confirmed the damage by longitudinal analysis of clinically relevant outcomes, including analyses by adaptive optics and optical coherence tomography/angiography, along with automated image analysis. By imparting a tunable yet targeted damage to the porcine CC and visual streak - with a structure similar to the human macula - this model is optimal for testing cell and gene therapies for outer retinal diseases including AMD, retinitis pigmentosa, Stargardt, and choroideremia. The amenability of this model to clinically relevant imaging outcomes will facilitate faster translation to patients.
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Affiliation(s)
| | - Juan Amaral
- National Eye Institute (NEI), NIH, Bethesda, Maryland, USA
| | - Irina Bunea
- National Eye Institute (NEI), NIH, Bethesda, Maryland, USA
| | | | - Rohan Gupta
- National Eye Institute (NEI), NIH, Bethesda, Maryland, USA
| | - Rishabh Gupta
- National Eye Institute (NEI), NIH, Bethesda, Maryland, USA
| | - Dara Baker
- National Eye Institute (NEI), NIH, Bethesda, Maryland, USA
| | - M Joseph Phillips
- McPherson Eye Research Institute and Waisman Center, and
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, Wisconsin, USA
| | - Richard J Blanch
- Academic Department of Military Surgery and Trauma, Royal Centre for Defense Medicine, Birmingham, United Kingdom
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, United Kingdom
- University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom
| | | | - David M Gamm
- McPherson Eye Research Institute and Waisman Center, and
- Department of Ophthalmology and Visual Sciences, University of Wisconsin, Madison, Wisconsin, USA
| | - Kapil Bharti
- National Eye Institute (NEI), NIH, Bethesda, Maryland, USA
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10
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Barbon E, Kawecki C, Marmier S, Sakkal A, Collaud F, Charles S, Ronzitti G, Casari C, Christophe OD, Denis CV, Lenting PJ, Mingozzi F. Development of a dual hybrid AAV vector for endothelial-targeted expression of von Willebrand factor. Gene Ther 2023; 30:245-254. [PMID: 33456057 PMCID: PMC10113149 DOI: 10.1038/s41434-020-00218-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Revised: 11/06/2020] [Accepted: 12/30/2020] [Indexed: 12/30/2022]
Abstract
Von Willebrand disease (VWD), the most common inherited bleeding disorder in humans, is caused by quantitative or qualitative defects in von Willebrand factor (VWF). VWD represents a potential target for gene therapy applications, as a single treatment could potentially result in a long-term correction of the disease. In recent years, several liver-directed gene therapy approaches have been exploited for VWD, but their efficacy was generally limited by the large size of the VWF transgene and the reduced hemostatic activity of the protein produced from hepatocytes. In this context, we aimed at developing a gene therapy strategy for gene delivery into endothelial cells, the natural site of biosynthesis of VWF. We optimized an endothelial-specific dual hybrid AAV vector, in which the large VWF cDNA was put under the control of an endothelial promoter and correctly reconstituted upon cell transduction by a combination of trans-splicing and homologous recombination mechanisms. In addition, we modified the AAV vector capsid by introducing an endothelial-targeting peptide to improve the efficiency for endothelial-directed gene transfer. This vector platform allowed the reconstitution of full-length VWF transgene both in vitro in human umbilical vein endothelial cells and in vivo in VWD mice, resulting in long-term expression of VWF.
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Affiliation(s)
- Elena Barbon
- Généthon, 91000, Evry, France
- Université Paris-Saclay, Université Evry, INSERM, Généthon, Integrare research unit UMR_S951, 91000, Evry, France
| | - Charlotte Kawecki
- Laboratory of Hemostasis, Inflammation and Thrombosis, Institut National de la Santé et de la Recherche Médicale UMR_1176, Université Paris-Saclay, 94276, Le Kremlin-Bicêtre, France
| | - Solenne Marmier
- Généthon, 91000, Evry, France
- Université Paris-Saclay, Université Evry, INSERM, Généthon, Integrare research unit UMR_S951, 91000, Evry, France
| | - Aboud Sakkal
- Généthon, 91000, Evry, France
- Université Paris-Saclay, Université Evry, INSERM, Généthon, Integrare research unit UMR_S951, 91000, Evry, France
| | - Fanny Collaud
- Généthon, 91000, Evry, France
- Université Paris-Saclay, Université Evry, INSERM, Généthon, Integrare research unit UMR_S951, 91000, Evry, France
| | - Severine Charles
- Généthon, 91000, Evry, France
- Université Paris-Saclay, Université Evry, INSERM, Généthon, Integrare research unit UMR_S951, 91000, Evry, France
| | - Giuseppe Ronzitti
- Généthon, 91000, Evry, France
- Université Paris-Saclay, Université Evry, INSERM, Généthon, Integrare research unit UMR_S951, 91000, Evry, France
| | - Caterina Casari
- Laboratory of Hemostasis, Inflammation and Thrombosis, Institut National de la Santé et de la Recherche Médicale UMR_1176, Université Paris-Saclay, 94276, Le Kremlin-Bicêtre, France
| | - Olivier D Christophe
- Laboratory of Hemostasis, Inflammation and Thrombosis, Institut National de la Santé et de la Recherche Médicale UMR_1176, Université Paris-Saclay, 94276, Le Kremlin-Bicêtre, France
| | - Cécile V Denis
- Laboratory of Hemostasis, Inflammation and Thrombosis, Institut National de la Santé et de la Recherche Médicale UMR_1176, Université Paris-Saclay, 94276, Le Kremlin-Bicêtre, France
| | - Peter J Lenting
- Laboratory of Hemostasis, Inflammation and Thrombosis, Institut National de la Santé et de la Recherche Médicale UMR_1176, Université Paris-Saclay, 94276, Le Kremlin-Bicêtre, France
| | - Federico Mingozzi
- Généthon, 91000, Evry, France.
- Université Paris-Saclay, Université Evry, INSERM, Généthon, Integrare research unit UMR_S951, 91000, Evry, France.
- Spark Therapeutics, Philadelphia, PA, 19103, USA.
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11
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Zin EA, Ozturk BE, Dalkara D, Byrne LC. Developing New Vectors for Retinal Gene Therapy. Cold Spring Harb Perspect Med 2023; 13:a041291. [PMID: 36987583 PMCID: PMC10691475 DOI: 10.1101/cshperspect.a041291] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Since their discovery over 55 years ago, adeno-associated virus (AAV) vectors have become powerful tools for experimental and therapeutic in vivo gene delivery, particularly in the retina. Increasing knowledge of AAV structure and biology has propelled forward the development of engineered AAV vectors with improved abilities for gene delivery. However, major obstacles to safe and efficient therapeutic gene delivery remain, including tropism, inefficient and untargeted gene delivery, and limited carrying capacity. Additional improvements to AAV vectors will be required to achieve therapeutic benefit while avoiding safety issues. In this review, we provide an overview of recent methods for engineering-enhanced AAV capsids, as well as remaining challenges that must be overcome to achieve optimized therapeutic gene delivery in the eye.
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Affiliation(s)
- Emilia A Zin
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
| | - Bilge E Ozturk
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
| | - Deniz Dalkara
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, F-75012 Paris, France
| | - Leah C Byrne
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
- Department of Neurobiology, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
- Department of Bioengineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15213, USA
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12
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Ferla R, Dell’Aquila F, Doria M, Ferraiuolo M, Noto A, Grazioli F, Ammendola V, Testa F, Melillo P, Iodice C, Risca G, Tedesco N, le Brun PR, Surace EM, Simonelli F, Galimberti S, Valsecchi MG, Marteau JB, Veron P, Colloca S, Auricchio A. Efficacy, pharmacokinetics, and safety in the mouse and primate retina of dual AAV vectors for Usher syndrome type 1B. Mol Ther Methods Clin Dev 2023; 28:396-411. [PMID: 36910588 PMCID: PMC9996380 DOI: 10.1016/j.omtm.2023.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Accepted: 02/07/2023] [Indexed: 02/12/2023]
Abstract
Gene therapy of Usher syndrome type 1B (USH1B) due to mutations in the large Myosin VIIA (MYO7A) gene is limited by the packaging capacity of adeno-associated viral (AAV) vectors. To overcome this, we have previously developed dual AAV8 vectors which encode human MYO7A (dual AAV8.MYO7A). Here we show that subretinal administration of 1.37E+9 to 1.37E+10 genome copies of a good-manufacturing-practice-like lot of dual AAV8.MYO7A improves the retinal defects of a mouse model of USH1B. The same lot was used in non-human primates at doses 1.6× and 4.3× the highest dose proposed for the clinical trial which was based on mouse efficacy data. Long-lasting alterations in retinal function and morphology were observed following subretinal administration of dual AAV8.MYO7A at the high dose. These findings were modest and improved over time in the low-dose group, as also observed in other studies involving the use of AAV8 in non-human primates and humans. Biodistribution and shedding studies confirmed the presence of vector DNA mainly in the visual pathway. Accordingly, we detected human MYO7A mRNA expression predominantly in the retina. Overall, these studies pave the way for the clinical translation of subretinal administration of dual AAV vectors in USH1B subjects.
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Affiliation(s)
- Rita Ferla
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Italy
- AAVantgarde BIO Srl, 20123 Milan, Italy
- Corresponding author: Rita Ferla, Telethon institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Italy; AAVantgarde BIO Srl, 20123 Milan, Italy
| | - Fabio Dell’Aquila
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Italy
| | - Monica Doria
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Italy
| | | | | | | | | | - Francesco Testa
- Eye Clinic, Multidisciplinary Department of Medical Surgical and Dental Sciences, University of Campania “Luigi Vanvitelli”, 80131 Naples, Italy
| | - Paolo Melillo
- Eye Clinic, Multidisciplinary Department of Medical Surgical and Dental Sciences, University of Campania “Luigi Vanvitelli”, 80131 Naples, Italy
| | - Carolina Iodice
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Italy
| | - Giulia Risca
- Center of Biostatistics for Clinical Epidemiology, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy
| | - Novella Tedesco
- Genethon, 91000 Evry, France
- Université Paris-Saclay, University Evry 91000, INSERM, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - Pierre Romain le Brun
- Genethon, 91000 Evry, France
- Université Paris-Saclay, University Evry 91000, INSERM, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | - Enrico Maria Surace
- Medical Genetics, Department of Translational Medicine, University of Naples “Federico II”, 80131 Naples, Italy
| | - Francesca Simonelli
- Eye Clinic, Multidisciplinary Department of Medical Surgical and Dental Sciences, University of Campania “Luigi Vanvitelli”, 80131 Naples, Italy
| | - Stefania Galimberti
- Center of Biostatistics for Clinical Epidemiology, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy
| | - Maria Grazia Valsecchi
- Center of Biostatistics for Clinical Epidemiology, School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy
| | | | - Philippe Veron
- Genethon, 91000 Evry, France
- Université Paris-Saclay, University Evry 91000, INSERM, Genethon, Integrare Research Unit UMR_S951, 91000 Evry, France
| | | | - Alberto Auricchio
- Telethon Institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Italy
- AAVantgarde BIO Srl, 20123 Milan, Italy
- Department of Advanced Biomedical Sciences, “Federico II” University, 80131 Naples, Italy
- Corresponding author: Alberto Auricchio, Telethon institute of Genetics and Medicine (TIGEM), Via Campi Flegrei 34, 80078 Pozzuoli, Italy; AAVantgarde BIO Srl, 20123 Milan, Italy.
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13
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Boye SE, Durham T, Laster A, Gelfman CM, Sahel JA. Identifying and Overcoming Challenges in Developing Effective Treatments for Usher 1B: A Workshop Report. Transl Vis Sci Technol 2023; 12:2. [PMID: 36723965 PMCID: PMC9904327 DOI: 10.1167/tvst.12.2.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Purpose To identify challenges and opportunities for the development of treatments for Usher syndrome (USH) type 1B. Methods In September 2021, the Foundation Fighting Blindness hosted a virtual workshop of clinicians, academic and industry researchers, advocates, and affected individuals and their families to discuss the challenges and opportunities for USH1B treatment development. Results The workshop began with insights from individuals affected by USH1B. Presentation topics included myosin VIIA protein function in the ear and eye and its role in disease pathology; challenges with the USH1B mouse model most used in disease research to date; new investigations into alternative disease models that may provide closer analogues to USH1B in the human retina, including retinal organoids and large animal models; and learnings from and limitations of available disease natural history data. Participants discussed the need for an open dialogue between researchers and regulators to design USH1B clinical trials with appropriate outcome measures of vision improvement, along with multimodal imaging of the retina and other testing approaches that can help inform trial designs. The workshop concluded with presentations and a roundtable reviewing emerging treatments, including USH1B-targeted genetic augmentation therapy and gene-agnostic approaches. Conclusions Initiatives like this workshop are important to foster all stakeholders in support of achieving the shared goal of treating and curing USH1B. Translational Relevance Presentations and discussions focused on overcoming disease modeling and clinical trial design challenges to facilitate development, testing, and implementation of effective USH1B treatments.
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Affiliation(s)
- Shannon E. Boye
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, FL, USA,Atsena Therapeutics, Inc., Durham, NC, USA
| | - Todd Durham
- Foundation Fighting Blindness, Columbia, MD, USA
| | - Amy Laster
- Foundation Fighting Blindness, Columbia, MD, USA
| | | | - José-Alain Sahel
- Sorbonne Université, INSERM, CNRS, Institut de la Vision, Paris, France,Department of Ophthalmology, The University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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14
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Pupo A, Fernández A, Low SH, François A, Suárez-Amarán L, Samulski RJ. AAV vectors: The Rubik's cube of human gene therapy. Mol Ther 2022; 30:3515-3541. [PMID: 36203359 PMCID: PMC9734031 DOI: 10.1016/j.ymthe.2022.09.015] [Citation(s) in RCA: 102] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/21/2022] [Accepted: 09/23/2022] [Indexed: 12/12/2022] Open
Abstract
Defective genes account for ∼80% of the total of more than 7,000 diseases known to date. Gene therapy brings the promise of a one-time treatment option that will fix the errors in patient genetic coding. Recombinant viruses are highly efficient vehicles for in vivo gene delivery. Adeno-associated virus (AAV) vectors offer unique advantages, such as tissue tropism, specificity in transduction, eliciting of a relatively low immune responses, no incorporation into the host chromosome, and long-lasting delivered gene expression, making them the most popular viral gene delivery system in clinical trials, with three AAV-based gene therapy drugs already approved by the US Food and Drug Administration (FDA) or European Medicines Agency (EMA). Despite the success of AAV vectors, their usage in particular scenarios is still limited due to remaining challenges, such as poor transduction efficiency in certain tissues, low organ specificity, pre-existing humoral immunity to AAV capsids, and vector dose-dependent toxicity in patients. In the present review, we address the different approaches to improve AAV vectors for gene therapy with a focus on AAV capsid selection and engineering, strategies to overcome anti-AAV immune response, and vector genome design, ending with a glimpse at vector production methods and the current state of recombinant AAV (rAAV) at the clinical level.
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Affiliation(s)
- Amaury Pupo
- R&D Department, Asklepios BioPharmaceutical, Inc. (AskBio), 20 T.W. Alexander, Suite 110 RTP, Durham, NC 27709, USA
| | - Audry Fernández
- R&D Department, Asklepios BioPharmaceutical, Inc. (AskBio), 20 T.W. Alexander, Suite 110 RTP, Durham, NC 27709, USA
| | - Siew Hui Low
- R&D Department, Asklepios BioPharmaceutical, Inc. (AskBio), 20 T.W. Alexander, Suite 110 RTP, Durham, NC 27709, USA
| | - Achille François
- Viralgen. Parque Tecnológico de Guipuzkoa, Edificio Kuatro, Paseo Mikeletegui, 83, 20009 San Sebastián, Spain
| | - Lester Suárez-Amarán
- R&D Department, Asklepios BioPharmaceutical, Inc. (AskBio), 20 T.W. Alexander, Suite 110 RTP, Durham, NC 27709, USA
| | - Richard Jude Samulski
- R&D Department, Asklepios BioPharmaceutical, Inc. (AskBio), 20 T.W. Alexander, Suite 110 RTP, Durham, NC 27709, USA,Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA,Corresponding author: Richard Jude Samulski, R&D Department, Asklepios BioPharmaceutical, Inc. (AskBio), 20 T.W. Alexander, Suite 110 RTP, NC 27709, USA.
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15
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Hasanzadeh A, Hamblin MR, Kiani J, Noori H, Hardie JM, Karimi M, Shafiee H. Could artificial intelligence revolutionize the development of nanovectors for gene therapy and mRNA vaccines? NANO TODAY 2022; 47:101665. [PMID: 37034382 PMCID: PMC10081506 DOI: 10.1016/j.nantod.2022.101665] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Gene therapy enables the introduction of nucleic acids like DNA and RNA into host cells, and is expected to revolutionize the treatment of a wide range of diseases. This growth has been further accelerated by the discovery of CRISPR/Cas technology, which allows accurate genomic editing in a broad range of cells and organisms in vitro and in vivo. Despite many advances in gene delivery and the development of various viral and non-viral gene delivery vectors, the lack of highly efficient non-viral systems with low cellular toxicity remains a challenge. The application of cutting-edge technologies such as artificial intelligence (AI) has great potential to find new paradigms to solve this issue. Herein, we review AI and its major subfields including machine learning (ML), neural networks (NNs), expert systems, deep learning (DL), computer vision and robotics. We discuss the potential of AI-based models and algorithms in the design of targeted gene delivery vehicles capable of crossing extracellular and intracellular barriers by viral mimicry strategies. We finally discuss the role of AI in improving the function of CRISPR/Cas systems, developing novel nanobots, and mRNA vaccine carriers.
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Affiliation(s)
- Akbar Hasanzadeh
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran 1449614535, Iran
- Department of Medical Nanotechnology, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran 1449614535, Iran
| | - Michael R Hamblin
- Laser Research Centre, Faculty of Health Science, University of Johannesburg, Doornfontein 2028, South Africa
- Radiation Biology Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Jafar Kiani
- Oncopathology Research Center, Iran University of Medical Sciences, Tehran 1449614535, Iran
- Department of Molecular Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Hamid Noori
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran 1449614535, Iran
- Department of Medical Nanotechnology, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran 1449614535, Iran
| | - Joseph M. Hardie
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, 02139 USA
| | - Mahdi Karimi
- Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran 1449614535, Iran
- Department of Medical Nanotechnology, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran 1449614535, Iran
- Oncopathology Research Center, Iran University of Medical Sciences, Tehran 1449614535, Iran
- Research Center for Science and Technology in Medicine, Tehran University of Medical Sciences, Tehran 141556559, Iran
- Applied Biotechnology Research Centre, Tehran Medical Science, Islamic Azad University, Tehran 1584743311, Iran
| | - Hadi Shafiee
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, 02139 USA
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16
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Chen ZR, Guo JY, He L, Liu S, Xu JY, Yang ZJ, Su W, Liu K, Gong SS, Wang GP. Co-transduction of dual-adeno-associated virus vectors in the neonatal and adult mouse utricles. Front Mol Neurosci 2022; 15:1020803. [PMID: 36340687 PMCID: PMC9629838 DOI: 10.3389/fnmol.2022.1020803] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 09/23/2022] [Indexed: 01/09/2024] Open
Abstract
Adeno-associated virus (AAV)-mediated gene transfer is an efficient method of gene over-expression in the vestibular end organs. However, AAV has limited usefulness for delivering a large gene, or multiple genes, due to its small packaging capacity (< 5 kb). Co-transduction of dual-AAV vectors can be used to increase the packaging capacity for gene delivery to various organs and tissues. However, its usefulness has not been well validated in the vestibular sensory epithelium. In the present study, we characterized the co-transduction of dual-AAV vectors in mouse utricles following inoculation of two AAV-serotype inner ear (AAV-ie) vectors via canalostomy. Firstly, co-transduction efficiencies were compared between dual-AAV-ie vectors using two different promoters: cytomegalovirus (CMV) and CMV early enhancer/chicken β-actin (CAG). In the group of dual AAV-ie-CAG vectors, the co-transduction rates for striolar hair cells (HCs), extrastriolar HCs, striolar supporting cells (SCs), and extrastriolar SCs were 23.14 ± 2.25%, 27.05 ± 2.10%, 57.65 ± 7.21%, and 60.33 ± 5.69%, respectively. The co-transduction rates in the group of dual AAV-ie-CMV vectors were comparable to those in the dual AAV-ie-CAG group. Next, we examined the co-transduction of dual-AAV-ie-CAG vectors in the utricles of neonatal mice and damaged adult mice. In the neonatal mice, co-transduction rates were 52.88 ± 3.11% and 44.93 ± 2.06% in the striolar and extrastriolar HCs, respectively, which were significantly higher than those in adult mice. In the Pou4f3+/DTR mice, following diphtheria toxin administration, which eliminated most HCs and spared the SCs, the co-transduction rate of SCs was not significantly different to that of normal utricles. Transgene expression persisted for up to 3 months in the adult mice. Furthermore, sequential administration of two AAV-ie-CAG vectors at an interval of 1 week resulted in a higher co-transduction rate in HCs than concurrent delivery. The auditory brainstem responses and swim tests did not reveal any disruption of auditory or vestibular function after co-transduction with dual-AAV-ie vectors. In conclusion, dual-AAV-ie vectors allow efficient co-transduction in the vestibular sensory epithelium and facilitate the delivery of large or multiple genes for vestibular gene therapy.
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Affiliation(s)
- Zhong-Rui Chen
- Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Jing-Ying Guo
- Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Lu He
- Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Shan Liu
- Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Jun-Yi Xu
- Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Zi-Jing Yang
- Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Wei Su
- Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Ke Liu
- Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Shu-Sheng Gong
- Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
| | - Guo-Peng Wang
- Department of Otolaryngology-Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, Beijing, China
- Clinical Center for Hearing Loss, Capital Medical University, Beijing, China
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17
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Marrone L, Marchi PM, Azzouz M. Circumventing the packaging limit of AAV-mediated gene replacement therapy for neurological disorders. Expert Opin Biol Ther 2022; 22:1163-1176. [PMID: 34904932 DOI: 10.1080/14712598.2022.2012148] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 11/25/2021] [Indexed: 12/19/2022]
Abstract
INTRODUCTION Gene therapy provides the exciting opportunity of a curative single treatment for devastating diseases, eradicating the need for chronic medication. Adeno-associated viruses (AAVs) are among the most attractive vector carriers for gene replacement in vivo. Yet, despite the success of recent AAV-based clinical trials, the clinical use of these vectors has been limited. For instance, the AAV packaging capacity is restricted to ~4.7 kb, making it a substantial challenge to deliver large gene products. AREAS COVERED In this review, we explore established and emerging strategies that circumvent the packaging limit of AAVs to make them effective vehicles for gene replacement therapy of monogenic disorders, with a particular focus on diseases affecting the nervous system. We report historical references, design remarks, as well as strengths and weaknesses of these approaches. We additionally discuss examples of neurological disorders for which such strategies have been attempted. EXPERT OPINION The field of AAV-gene therapy has experienced enormous advancements in the last decade. However, there is still ample space for improvement aimed at overcoming existing challenges that are slowing down the progressive trajectory of this field.
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Affiliation(s)
- Lara Marrone
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Paolo M Marchi
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
| | - Mimoun Azzouz
- Department of Neuroscience, Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, UK
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18
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Panikker P, Roy S, Ghosh A, Poornachandra B, Ghosh A. Advancing precision medicines for ocular disorders: Diagnostic genomics to tailored therapies. Front Med (Lausanne) 2022; 9:906482. [PMID: 35911417 PMCID: PMC9334564 DOI: 10.3389/fmed.2022.906482] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 06/29/2022] [Indexed: 11/20/2022] Open
Abstract
Successful sequencing of the human genome and evolving functional knowledge of gene products has taken genomic medicine to the forefront, soon combining broadly with traditional diagnostics, therapeutics, and prognostics in patients. Recent years have witnessed an extraordinary leap in our understanding of ocular diseases and their respective genetic underpinnings. As we are entering the age of genomic medicine, rapid advances in genome sequencing, gene delivery, genome surgery, and computational genomics enable an ever-increasing capacity to provide a precise and robust diagnosis of diseases and the development of targeted treatment strategies. Inherited retinal diseases are a major source of blindness around the world where a large number of causative genes have been identified, paving the way for personalized diagnostics in the clinic. Developments in functional genetics and gene transfer techniques has also led to the first FDA approval of gene therapy for LCA, a childhood blindness. Many such retinal diseases are the focus of various clinical trials, making clinical diagnoses of retinal diseases, their underlying genetics and the studies of natural history important. Here, we review methodologies for identifying new genes and variants associated with various ocular disorders and the complexities associated with them. Thereafter we discuss briefly, various retinal diseases and the application of genomic technologies in their diagnosis. We also discuss the strategies, challenges, and potential of gene therapy for the treatment of inherited and acquired retinal diseases. Additionally, we discuss the translational aspects of gene therapy, the important vector types and considerations for human trials that may help advance personalized therapeutics in ophthalmology. Retinal disease research has led the application of precision diagnostics and precision therapies; therefore, this review provides a general understanding of the current status of precision medicine in ophthalmology.
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Affiliation(s)
| | - Shomereeta Roy
- Grow Research Laboratory, Narayana Nethralaya Foundation, Bengaluru, India
| | - Anuprita Ghosh
- Grow Research Laboratory, Narayana Nethralaya Foundation, Bengaluru, India
| | | | - Arkasubhra Ghosh
- Grow Research Laboratory, Narayana Nethralaya Foundation, Bengaluru, India
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19
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Ryu J, Statz JP, Chan W, Burch FC, Brigande JV, Kempton B, Porsov EV, Renner L, McGill T, Burwitz BJ, Hanna CB, Neuringer M, Hennebold JD. CRISPR/Cas9 editing of the MYO7A gene in rhesus macaque embryos to generate a primate model of Usher syndrome type 1B. Sci Rep 2022; 12:10036. [PMID: 35710827 PMCID: PMC9203743 DOI: 10.1038/s41598-022-13689-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 05/26/2022] [Indexed: 12/02/2022] Open
Abstract
Mutations in the MYO7A gene lead to Usher syndrome type 1B (USH1B), a disease characterized by congenital deafness, vision loss, and balance impairment. To create a nonhuman primate (NHP) USH1B model, CRISPR/Cas9 was used to disrupt MYO7A in rhesus macaque zygotes. The targeting efficiency of Cas9 mRNA and hybridized crRNA-tracrRNA (hyb-gRNA) was compared to Cas9 nuclease (Nuc) protein and synthetic single guide (sg)RNAs. Nuc/sgRNA injection led to higher editing efficiencies relative to mRNA/hyb-gRNAs. Mutations were assessed by preimplantation genetic testing (PGT) and those with the desired mutations were transferred into surrogates. A pregnancy was established from an embryo where 92.1% of the PGT sequencing reads possessed a single G insertion that leads to a premature stop codon. Analysis of single peripheral blood leukocytes from the infant revealed that half the cells possessed the homozygous single base insertion and the remaining cells had the wild-type MYO7A sequence. The infant showed sensitive auditory thresholds beginning at 3 months. Although further optimization is needed, our studies demonstrate that it is feasible to use CRISPR technologies for creating NHP models of human diseases.
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Affiliation(s)
- Junghyun Ryu
- Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA
| | - John P Statz
- Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA
- Division of Biological Sciences, University of Montana, Missoula, MT, 59812, USA
| | - William Chan
- Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA
- University of Texas Southwestern Medical School, 5323 Harry Hines Blvd, Dallas, TX, 75390, USA
| | - Fernanda C Burch
- Assisted Reproductive Technologies Core, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA
| | - John V Brigande
- Department of Otolaryngology, Oregon Hearing Research Center, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Beth Kempton
- Department of Otolaryngology, Oregon Hearing Research Center, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Edward V Porsov
- Department of Otolaryngology, Oregon Hearing Research Center, Oregon Health and Science University, Portland, OR, 97239, USA
| | - Lauren Renner
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA
| | - Trevor McGill
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA
- Department of Ophthalmology, Casey Eye Institute, Oregon Health and Science University, Beaverton, OR, 97006, USA
| | - Benjamin J Burwitz
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR, 97006, USA
| | - Carol B Hanna
- Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA
- Assisted Reproductive Technologies Core, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA
| | - Martha Neuringer
- Division of Neuroscience, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA
- Department of Ophthalmology, Casey Eye Institute, Oregon Health and Science University, Beaverton, OR, 97006, USA
| | - Jon D Hennebold
- Division of Reproductive and Developmental Sciences, Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, 97006, USA.
- Department of Obstetrics and Gynecology, Oregon Health and Science University, Portland, OR, 97239, USA.
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20
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Tornabene P, Ferla R, Llado-Santaeularia M, Centrulo M, Dell'Anno M, Esposito F, Marrocco E, Pone E, Minopoli R, Iodice C, Nusco E, Rossi S, Lyubenova H, Manfredi A, Di Filippo L, Iuliano A, Torella A, Piluso G, Musacchia F, Surace EM, Cacchiarelli D, Nigro V, Auricchio A. Therapeutic homology-independent targeted integration in retina and liver. Nat Commun 2022; 13:1963. [PMID: 35414130 PMCID: PMC9005519 DOI: 10.1038/s41467-022-29550-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Accepted: 03/16/2022] [Indexed: 01/08/2023] Open
Abstract
Challenges to the widespread application of gene therapy with adeno-associated viral (AAV) vectors include dominant conditions due to gain-of-function mutations which require allele-specific knockout, as well as long-term transgene expression from proliferating tissues, which is hampered by AAV DNA episomal status. To overcome these challenges, we used CRISPR/Cas9-mediated homology-independent targeted integration (HITI) in retina and liver as paradigmatic target tissues. We show that AAV-HITI targets photoreceptors of both mouse and pig retina, and this results in significant improvements to retinal morphology and function in mice with autosomal dominant retinitis pigmentosa. In addition, we show that neonatal systemic AAV-HITI delivery achieves stable liver transgene expression and phenotypic improvement in a mouse model of a severe lysosomal storage disease. We also show that HITI applications predominantly result in on-target editing. These results lay the groundwork for the application of AAV-HITI for the treatment of diseases affecting various organs.
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Affiliation(s)
- Patrizia Tornabene
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy.,Medical Genetics, Department of Translational Medicine, Federico II University, 80131, Naples, Italy
| | - Rita Ferla
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy.,Medical Genetics, Department of Translational Medicine, Federico II University, 80131, Naples, Italy
| | | | - Miriam Centrulo
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy
| | - Margherita Dell'Anno
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy.,Medical Genetics, Department of Translational Medicine, Federico II University, 80131, Naples, Italy
| | - Federica Esposito
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy
| | - Elena Marrocco
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy
| | - Emanuela Pone
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy.,Medical Genetics, Department of Translational Medicine, Federico II University, 80131, Naples, Italy
| | - Renato Minopoli
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy
| | - Carolina Iodice
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy
| | - Edoardo Nusco
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy
| | - Settimio Rossi
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania L. Vanvitelli, 80131, Naples, Italy
| | | | - Anna Manfredi
- Telethon Institute of Genetics and Medicine (TIGEM), Armenise/Harvard Laboratory of Integrative Genomics, 80078, Pozzuoli, Italy.,Next Generation Diagnostic Srl, 80078, Pozzuoli, Italy
| | | | - Antonella Iuliano
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy
| | - Annalaura Torella
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy.,Department of Precision Medicine, University of Campania L. Vanvitelli, 80138, Naples, Italy
| | - Giulio Piluso
- Department of Precision Medicine, University of Campania L. Vanvitelli, 80138, Naples, Italy
| | | | - Enrico Maria Surace
- Medical Genetics, Department of Translational Medicine, Federico II University, 80131, Naples, Italy
| | - Davide Cacchiarelli
- Telethon Institute of Genetics and Medicine (TIGEM), Armenise/Harvard Laboratory of Integrative Genomics, 80078, Pozzuoli, Italy.,Department of Translational Medicine, Federico II University, 80131, Naples, Italy
| | - Vincenzo Nigro
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy.,Department of Precision Medicine, University of Campania L. Vanvitelli, 80138, Naples, Italy
| | - Alberto Auricchio
- Telethon Institute of Genetics and Medicine (TIGEM), 80078, Pozzuoli, Italy. .,Medical Genetics, Department of Advanced Biomedical Sciences, Federico II University, 80131, Naples, Italy.
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21
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Yeh CF, Cheng SH, Lin YS, Shentu TP, Huang RT, Zhu J, Chen YT, Kumar S, Lin MS, Kao HL, Huang PH, Roselló-Sastre E, Garcia F, Jo H, Fang Y, Yang KC. Targeting mechanosensitive endothelial TXNDC5 to stabilize eNOS and reduce atherosclerosis in vivo. SCIENCE ADVANCES 2022; 8:eabl8096. [PMID: 35061532 PMCID: PMC8782452 DOI: 10.1126/sciadv.abl8096] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 11/29/2021] [Indexed: 05/26/2023]
Abstract
Although atherosclerosis preferentially develops at arterial curvatures and bifurcations where disturbed flow (DF) activates endothelium, therapies targeting flow-dependent mechanosensing pathways in the vasculature are unavailable. Here, we provided experimental evidence demonstrating a previously unidentified causal role of DF-induced endothelial TXNDC5 (thioredoxin domain containing 5) in atherosclerosis. TXNDC5 was increased in human and mouse atherosclerotic lesions and induced in endothelium subjected to DF. Endothelium-specific Txndc5 deletion markedly reduced atherosclerosis in ApoE-/- mice. Mechanistically, DF-induced TXNDC5 increases proteasome-mediated degradation of heat shock factor 1, leading to reduced heat shock protein 90 and accelerated eNOS (endothelial nitric oxide synthase) protein degradation. Moreover, nanoparticles formulated to deliver Txndc5-targeting CRISPR-Cas9 plasmids driven by an endothelium-specific promoter (CDH5) significantly increase eNOS protein and reduce atherosclerosis in ApoE-/- mice. These results delineate a new molecular paradigm that DF-induced endothelial TXNDC5 promotes atherosclerosis and establish a proof of concept of targeting endothelial mechanosensitive pathways in vivo against atherosclerosis.
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Affiliation(s)
- Chih-Fan Yeh
- Division of Cardiology, Department of Internal Medicine and Cardiovascular Center, National Taiwan University Hospital, Taipei, Taiwan
- Department and Graduate Institute of Pharmacology, National Taiwan University College of Medicine, Taipei, Taiwan
- Department of Medicine, Biological Sciences Division and College, The University of Chicago, Chicago, IL, USA
| | - Shih-Hsin Cheng
- Department and Graduate Institute of Pharmacology, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yu-Shan Lin
- Department and Graduate Institute of Pharmacology, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Tzu-Pin Shentu
- Department of Medicine, Biological Sciences Division and College, The University of Chicago, Chicago, IL, USA
| | - Ru-Ting Huang
- Department of Medicine, Biological Sciences Division and College, The University of Chicago, Chicago, IL, USA
| | - Jiayu Zhu
- Department of Medicine, Biological Sciences Division and College, The University of Chicago, Chicago, IL, USA
| | - Yen-Ting Chen
- Department and Graduate Institute of Pharmacology, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Sandeep Kumar
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Mao-Shin Lin
- Division of Cardiology, Department of Internal Medicine and Cardiovascular Center, National Taiwan University Hospital, Taipei, Taiwan
| | - Hsien-Li Kao
- Division of Cardiology, Department of Internal Medicine and Cardiovascular Center, National Taiwan University Hospital, Taipei, Taiwan
| | - Po-Hsun Huang
- Division of Cardiology, Department of Internal Medicine, Veteran General Hospital, Taipei, Taiwan
| | - Esther Roselló-Sastre
- Department of Anatomic Pathology, Hospital General Universitario de Castellón, Castellón, Spain
| | - Francisca Garcia
- Department of Vascular Surgery, Hospital General Universitario de Castellón, Castellón, Spain
- Department of Health Sciences, Universidad CEU Cardenal Herrera, Valencia, Spain
| | - Hanjoong Jo
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Yun Fang
- Department of Medicine, Biological Sciences Division and College, The University of Chicago, Chicago, IL, USA
| | - Kai-Chien Yang
- Division of Cardiology, Department of Internal Medicine and Cardiovascular Center, National Taiwan University Hospital, Taipei, Taiwan
- Department and Graduate Institute of Pharmacology, National Taiwan University College of Medicine, Taipei, Taiwan
- Research Center for Developmental Biology and Regenerative Medicine, National Taiwan University, Taipei, Taiwan
- Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan
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22
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Xiao X, Ye L, Chen C, Zheng H, Yuan J. Clinical Observation and Genotype-Phenotype Analysis of ABCA4- Related Hereditary Retinal Degeneration before Gene Therapy. Curr Gene Ther 2022; 22:342-351. [PMID: 35170407 PMCID: PMC10495610 DOI: 10.2174/1566523222666220216101539] [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: 08/17/2021] [Revised: 12/09/2021] [Accepted: 12/10/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Hereditary retinal degeneration (HRD) is an irreversible eye disease that results in blindness in severe cases. It is most commonly caused by variants in the ABCA4 gene. HRD presents a high degree of clinical and genetic heterogeneity. We determined genotypic and phenotypic correlations, in the natural course of clinical observation, of unrelated progenitors of HRD associated with ABCA4. OBJECTIVE To analyze the relationship between the phenotypes and genotypes of ABCA4 variants. METHODS A retrospective clinical study of five cases from the ophthalmology department of the People's Hospital of Wuhan University from January 2019 to October 2020 was conducted. We tested for ABCA4 variants in the probands. We performed eye tests, including the best-corrected visual acuity, super-wide fundus photography and spontaneous fluorescence photography, optical coherence tomography, and electrophysiological examination. RESULTS Disease-causing variants were identified in the ABCA4 genes of all patients. Among these, seven ABCA4 variants were novel. All patients were sporadic cases; only one patient had parents who were relatives, and the other four patients were offspring of unrelated parents. Two patients presented with Stargardt disease, mainly with macular lesions, two presented with retinitis pigmentosa (cone-rod type), and one presented with cone dystrophy. The visual acuity and visual field of the five patients showed varying degrees of deterioration and impairment. CONCLUSION The same ABCA4 mutation can lead to different clinical phenotypes, and there is variation in the degree of damage to vision, visual field, and electrophysiology among different clinical phenotypes. Clinicians must differentiate between and diagnose pathologies resulting from this mutation.
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Affiliation(s)
- Xuan Xiao
- Eye Center, Renmin Hospital of Wuhan University, Wuhan University, Hubei, Wuhan 430060, China
| | - Lin Ye
- Department of Eye Plastic and Lacrimal Diseases, Shenzhen Eye Hospital, Shenzhen, China
| | - Changzheng Chen
- Eye Center, Renmin Hospital of Wuhan University, Wuhan University, Hubei, Wuhan 430060, China
| | - Hongmei Zheng
- Eye Center, Renmin Hospital of Wuhan University, Wuhan University, Hubei, Wuhan 430060, China
| | - Jiajia Yuan
- Eye Center, Renmin Hospital of Wuhan University, Wuhan University, Hubei, Wuhan 430060, China
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23
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Huang D, Heath Jeffery RC, Aung-Htut MT, McLenachan S, Fletcher S, Wilton SD, Chen FK. Stargardt disease and progress in therapeutic strategies. Ophthalmic Genet 2021; 43:1-26. [PMID: 34455905 DOI: 10.1080/13816810.2021.1966053] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Background: Stargardt disease (STGD1) is an autosomal recessive retinal dystrophy due to mutations in ABCA4, characterized by subretinal deposition of lipofuscin-like substances and bilateral centrifugal vision loss. Despite the tremendous progress made in the understanding of STGD1, there are no approved treatments to date. This review examines the challenges in the development of an effective STGD1 therapy.Materials and Methods: A literature review was performed through to June 2021 summarizing the spectrum of retinal phenotypes in STGD1, the molecular biology of ABCA4 protein, the in vivo and in vitro models used to investigate the mechanisms of ABCA4 mutations and current clinical trials.Results: STGD1 phenotypic variability remains an challenge for clinical trial design and patient selection. Pre-clinical development of therapeutic options has been limited by the lack of animal models reflecting the diverse phenotypic spectrum of STDG1. Patient-derived cell lines have facilitated the characterization of splice mutations but the clinical presentation is not always predicted by the effect of specific mutations on retinoid metabolism in cellular models. Current therapies primarily aim to delay vision loss whilst strategies to restore vision are less well developed.Conclusions: STGD1 therapy development can be accelerated by a deeper understanding of genotype-phenotype correlations.
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Affiliation(s)
- Di Huang
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Western Australia, Australia.,Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), the University of Western Australia, Nedlands, Western Australia, Australia.,Perron Institute for Neurological and Translational Science & the University of Western Australia, Nedlands, Western Australia, Australia
| | - Rachael C Heath Jeffery
- Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), the University of Western Australia, Nedlands, Western Australia, Australia
| | - May Thandar Aung-Htut
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Western Australia, Australia.,Perron Institute for Neurological and Translational Science & the University of Western Australia, Nedlands, Western Australia, Australia
| | - Samuel McLenachan
- Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), the University of Western Australia, Nedlands, Western Australia, Australia
| | - Sue Fletcher
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Western Australia, Australia.,Perron Institute for Neurological and Translational Science & the University of Western Australia, Nedlands, Western Australia, Australia
| | - Steve D Wilton
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Western Australia, Australia.,Perron Institute for Neurological and Translational Science & the University of Western Australia, Nedlands, Western Australia, Australia
| | - Fred K Chen
- Centre for Ophthalmology and Visual Science (Incorporating Lions Eye Institute), the University of Western Australia, Nedlands, Western Australia, Australia.,Australian Inherited Retinal Disease Registry and DNA Bank, Department of Medical Technology and Physics, Sir Charles Gairdner Hospital, Nedlands, Western Australia, Australia.,Department of Ophthalmology, Royal Perth Hospital, Perth, Western Australia, Australia.,Department of Ophthalmology, Perth Children's Hospital, Nedlands, Western Australia, Australia
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24
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Al-Khuzaei S, Broadgate S, Foster CR, Shah M, Yu J, Downes SM, Halford S. An Overview of the Genetics of ABCA4 Retinopathies, an Evolving Story. Genes (Basel) 2021; 12:1241. [PMID: 34440414 PMCID: PMC8392661 DOI: 10.3390/genes12081241] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Revised: 08/09/2021] [Accepted: 08/10/2021] [Indexed: 11/16/2022] Open
Abstract
Stargardt disease (STGD1) and ABCA4 retinopathies (ABCA4R) are caused by pathogenic variants in the ABCA4 gene inherited in an autosomal recessive manner. The gene encodes an importer flippase protein that prevents the build-up of vitamin A derivatives that are toxic to the RPE. Diagnosing ABCA4R is complex due to its phenotypic variability and the presence of other inherited retinal dystrophy phenocopies. ABCA4 is a large gene, comprising 50 exons; to date > 2000 variants have been described. These include missense, nonsense, splicing, structural, and deep intronic variants. Missense variants account for the majority of variants in ABCA4. However, in a significant proportion of patients with an ABCA4R phenotype, a second variant in ABCA4 is not identified. This could be due to the presence of yet unknown variants, or hypomorphic alleles being incorrectly classified as benign, or the possibility that the disease is caused by a variant in another gene. This underlines the importance of accurate genetic testing. The pathogenicity of novel variants can be predicted using in silico programs, but these rely on databases that are not ethnically diverse, thus highlighting the need for studies in differing populations. Functional studies in vitro are useful towards assessing protein function but do not directly measure the flippase activity. Obtaining an accurate molecular diagnosis is becoming increasingly more important as targeted therapeutic options become available; these include pharmacological, gene-based, and cell replacement-based therapies. The aim of this review is to provide an update on the current status of genotyping in ABCA4 and the status of the therapeutic approaches being investigated.
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Affiliation(s)
- Saoud Al-Khuzaei
- Oxford Eye Hospital, John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 9DU, UK; (S.A.-K.); (M.S.)
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neuroscience, University of Oxford, Level 6 John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK; (S.B.); (J.Y.)
| | - Suzanne Broadgate
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neuroscience, University of Oxford, Level 6 John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK; (S.B.); (J.Y.)
| | | | - Mital Shah
- Oxford Eye Hospital, John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 9DU, UK; (S.A.-K.); (M.S.)
| | - Jing Yu
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neuroscience, University of Oxford, Level 6 John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK; (S.B.); (J.Y.)
| | - Susan M. Downes
- Oxford Eye Hospital, John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford OX3 9DU, UK; (S.A.-K.); (M.S.)
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neuroscience, University of Oxford, Level 6 John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK; (S.B.); (J.Y.)
| | - Stephanie Halford
- Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neuroscience, University of Oxford, Level 6 John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK; (S.B.); (J.Y.)
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25
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Piotter E, McClements ME, MacLaren RE. Therapy Approaches for Stargardt Disease. Biomolecules 2021; 11:1179. [PMID: 34439845 PMCID: PMC8393614 DOI: 10.3390/biom11081179] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Revised: 07/27/2021] [Accepted: 08/05/2021] [Indexed: 12/14/2022] Open
Abstract
Despite being the most prevalent cause of inherited blindness in children, Stargardt disease is yet to achieve the same clinical trial success as has been achieved for other inherited retinal diseases. With an early age of onset and continual progression of disease over the life course of an individual, Stargardt disease appears to lend itself to therapeutic intervention. However, the aetiology provides issues not encountered with the likes of choroideremia and X-linked retinitis pigmentosa and this has led to a spectrum of treatment strategies that approach the problem from different aspects. These include therapeutics ranging from small molecules and anti-sense oligonucleotides to viral gene supplementation and cell replacement. The advancing development of CRISPR-based molecular tools is also likely to contribute to future therapies by way of genome editing. In this we review, we consider the most recent pre-clinical and clinical trial data relating to the different strategies being applied to the problem of generating a treatment for the large cohort of Stargardt disease patients worldwide.
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Affiliation(s)
- Elena Piotter
- Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK; (E.P.); (M.E.M.)
- Oxford University Hospitals NHS Foundation Trust NIHR Biomedical Research Centre, Oxford OX3 9DU, UK
| | - Michelle E McClements
- Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK; (E.P.); (M.E.M.)
- Oxford University Hospitals NHS Foundation Trust NIHR Biomedical Research Centre, Oxford OX3 9DU, UK
| | - Robert E MacLaren
- Nuffield Laboratory of Ophthalmology, Department of Clinical Neurosciences, University of Oxford, Oxford OX3 9DU, UK; (E.P.); (M.E.M.)
- Oxford University Hospitals NHS Foundation Trust NIHR Biomedical Research Centre, Oxford OX3 9DU, UK
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26
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Quinlan C, Rheault MN. Genetic Basis of Type IV Collagen Disorders of the Kidney. Clin J Am Soc Nephrol 2021; 16:1101-1109. [PMID: 33849932 PMCID: PMC8425620 DOI: 10.2215/cjn.19171220] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The glomerular basement membrane is a vital component of the filtration barrier of the kidney and is primarily composed of a highly structured matrix of type IV collagen. Specific isoforms of type IV collagen, the α3(IV), α4(IV), and α5(IV) isoforms, assemble into trimers that are required for normal glomerular basement membrane function. Disruption or alteration in these isoforms leads to breakdown of the glomerular basement membrane structure and function and can lead to progressive CKD known as Alport syndrome. However, there is wide variability in phenotype among patients with mutations affecting type IV collagen that depends on a complex interplay of sex, genotype, and X-chromosome inactivation. This article reviews the genetic basis of collagen disorders of the kidney as well as potential treatments for these conditions, including direct alteration of the DNA, RNA therapies, and manipulation of collagen proteins.
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Affiliation(s)
- Catherine Quinlan
- Department of Nephrology, Royal Children’s Hospital, Melbourne, Victoria, Australia,Department of Kidney Regeneration, Murdoch Children’s Research Institute, Melbourne, Victoria, Australia,Department of Paediatrics, University of Melbourne, Melbourne, Victoria, Australia
| | - Michelle N. Rheault
- Division of Pediatric Nephrology, Department of Pediatrics, University of Minnesota Masonic Children’s Hospital, Minneapolis, Minnesota
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27
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Hu ML, Edwards TL, O'Hare F, Hickey DG, Wang JH, Liu Z, Ayton LN. Gene therapy for inherited retinal diseases: progress and possibilities. Clin Exp Optom 2021; 104:444-454. [PMID: 33689657 DOI: 10.1080/08164622.2021.1880863] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Inherited retinal diseases (IRDs) comprise a heterogeneous group of genetic disorders affecting the retina. Caused by mutations in over 300 genes, IRDs result in visual impairment due to dysfunction and degeneration of photoreceptors, retinal pigment epithelium, or the choroid. Important photoreceptor IRDs include retinitis pigmentosa and Leber congenital amaurosis. Macular dystrophies include Stargardt and Best disease. Currently, IRDs are largely incurable but the landscape of treatment options is rapidly changing for these diseases which, untreated, result in severe visual impairment and blindness.Advances in DNA delivery to the retina and improved genetic diagnosis of IRDs have led to a new era of research into gene therapy for these vision-threatening disorders. Gene therapy is a compelling approach due to the monogenic nature of most IRDs, with the retina being a favourable target for administering genetic vectors due to its immunoprivileged environment, direct visibility, and multiple methods to assess sensitivity and function. Generally, retinal gene therapy involves a subretinal or intravitreal injection of a viral vector, which infects target cells to deliver a therapeutic gene, or transgene. A gene augmentation strategy introduces a functioning copy of a gene to restore expression of a mutated gene, whereas a gene-editing strategy aims to directly edit and correct the mutation. Common delivery vectors include adeno-associated virus (AAV) and lentivirus.Voretigene neparvovec-rzyl (Luxturna) became the first FDA-approved direct gene therapy in December 2017, and the Australian TGA followed suit in August 2020. More are projected to follow, with clinical trials underway for many other IRDs.This review provides an overview of gene therapy for IRDs, including current progress and challenges. A companion article in this issue details target patient populations for IRD gene therapy, and how optometrists can assist in assessing individuals who may be eligible for current and future therapies.
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Affiliation(s)
- Monica L Hu
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Thomas L Edwards
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia.,Department of Surgery (Ophthalmology), Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Melbourne, Australia
| | - Fleur O'Hare
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia.,Department of Surgery (Ophthalmology), Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Melbourne, Australia.,Department of Optometry and Vision Sciences, Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Melbourne, Australia
| | - Doron G Hickey
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Jiang-Hui Wang
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Zhengyang Liu
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia
| | - Lauren N Ayton
- Centre for Eye Research Australia, Royal Victorian Eye and Ear Hospital, Melbourne, Australia.,Department of Surgery (Ophthalmology), Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Melbourne, Australia.,Department of Optometry and Vision Sciences, Faculty of Medicine, Dentistry and Health Sciences, the University of Melbourne, Melbourne, Australia
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Ran J, Zhou J. Targeting the photoreceptor cilium for the treatment of retinal diseases. Acta Pharmacol Sin 2020; 41:1410-1415. [PMID: 32753732 DOI: 10.1038/s41401-020-0486-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 06/28/2020] [Indexed: 02/08/2023] Open
Abstract
Photoreceptors, as polarised sensory neurons, are essential for light sensation and phototransduction, which are highly dependent on the photoreceptor cilium. Structural defects and/or dysfunction of the photoreceptor cilium caused by mutations in photoreceptor-specific genes or common ciliary genes can lead to retinal diseases, including syndromic and nonsyndromic diseases. In this review, we describe the structure and function of the photoreceptor cilium. We also discuss recent findings that underscore the dysregulation of the photoreceptor cilium in various retinal diseases and the therapeutic potential of targeting ciliary genes in these diseases.
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Toms M, Pagarkar W, Moosajee M. Usher syndrome: clinical features, molecular genetics and advancing therapeutics. Ther Adv Ophthalmol 2020; 12:2515841420952194. [PMID: 32995707 PMCID: PMC7502997 DOI: 10.1177/2515841420952194] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 07/27/2020] [Indexed: 01/12/2023] Open
Abstract
Usher syndrome has three subtypes, each being clinically and genetically heterogeneous characterised by sensorineural hearing loss and retinitis pigmentosa (RP), with or without vestibular dysfunction. It is the most common cause of deaf–blindness worldwide with a prevalence of between 4 and 17 in 100 000. To date, 10 causative genes have been identified for Usher syndrome, with MYO7A accounting for >50% of type 1 and USH2A contributing to approximately 80% of type 2 Usher syndrome. Variants in these genes can also cause non-syndromic RP and deafness. Genotype–phenotype correlations have been described for several of the Usher genes. Hearing loss is managed with hearing aids and cochlear implants, which has made a significant improvement in quality of life for patients. While there is currently no available approved treatment for the RP, various therapeutic strategies are in development or in clinical trials for Usher syndrome, including gene replacement, gene editing, antisense oligonucleotides and small molecule drugs.
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Affiliation(s)
- Maria Toms
- UCL Institute of Ophthalmology, London, UK; The Francis Crick Institute, London, UK
| | - Waheeda Pagarkar
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK; University College London Hospitals NHS Foundation Trust, London, UK
| | - Mariya Moosajee
- Development, Ageing and Disease, UCL Institute of Ophthalmology, 11-43 Bath Street, London EC1V 9EL, UK
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30
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Reisinger E. Dual-AAV delivery of large gene sequences to the inner ear. Hear Res 2020; 394:107857. [DOI: 10.1016/j.heares.2019.107857] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 11/22/2019] [Indexed: 01/06/2023]
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31
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Akil O. Dual and triple AAV delivery of large therapeutic gene sequences into the inner ear. Hear Res 2020; 394:107912. [DOI: 10.1016/j.heares.2020.107912] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 02/04/2020] [Accepted: 02/07/2020] [Indexed: 12/17/2022]
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French LS, Mellough CB, Chen FK, Carvalho LS. A Review of Gene, Drug and Cell-Based Therapies for Usher Syndrome. Front Cell Neurosci 2020; 14:183. [PMID: 32733204 PMCID: PMC7363968 DOI: 10.3389/fncel.2020.00183] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 05/28/2020] [Indexed: 12/12/2022] Open
Abstract
Usher syndrome is a genetic disorder causing neurosensory hearing loss and blindness from retinitis pigmentosa (RP). Adaptive techniques such as braille, digital and optical magnifiers, mobility training, cochlear implants, or other assistive listening devices are indispensable for reducing disability. However, there is currently no treatment to reduce or arrest sensory cell degeneration. There are several classes of treatments for Usher syndrome being investigated. The present article reviews the progress this research has made towards delivering commercial options for patients with Usher syndrome.
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Affiliation(s)
- Lucy S French
- Centre for Ophthalmology and Visual Sciences (incorporating Lions Eye Institute), The University of Western Australia, Nedlands, WA, Australia
| | - Carla B Mellough
- Centre for Ophthalmology and Visual Sciences (incorporating Lions Eye Institute), The University of Western Australia, Nedlands, WA, Australia
| | - Fred K Chen
- Centre for Ophthalmology and Visual Sciences (incorporating Lions Eye Institute), The University of Western Australia, Nedlands, WA, Australia.,Department of Ophthalmology, Royal Perth Hospital, Perth, WA, Australia.,Department of Ophthalmology, Perth Children's Hospital, Nedlands, WA, Australia
| | - Livia S Carvalho
- Centre for Ophthalmology and Visual Sciences (incorporating Lions Eye Institute), The University of Western Australia, Nedlands, WA, Australia
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Tornabene P, Trapani I, Minopoli R, Centrulo M, Lupo M, de Simone S, Tiberi P, Dell'Aquila F, Marrocco E, Iodice C, Iuliano A, Gesualdo C, Rossi S, Giaquinto L, Albert S, Hoyng CB, Polishchuk E, Cremers FPM, Surace EM, Simonelli F, De Matteis MA, Polishchuk R, Auricchio A. Intein-mediated protein trans-splicing expands adeno-associated virus transfer capacity in the retina. Sci Transl Med 2020; 11:11/492/eaav4523. [PMID: 31092694 DOI: 10.1126/scitranslmed.aav4523] [Citation(s) in RCA: 104] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 11/21/2018] [Accepted: 04/04/2019] [Indexed: 12/26/2022]
Abstract
Retinal gene therapy with adeno-associated viral (AAV) vectors holds promises for treating inherited and noninherited diseases of the eye. Although clinical data suggest that retinal gene therapy is safe and effective, delivery of large genes is hindered by the limited AAV cargo capacity. Protein trans-splicing mediated by split inteins is used by single-cell organisms to reconstitute proteins. Here, we show that delivery of multiple AAV vectors each encoding one of the fragments of target proteins flanked by short split inteins results in protein trans-splicing and full-length protein reconstitution in the retina of mice and pigs and in human retinal organoids. The reconstitution of large therapeutic proteins using this approach improved the phenotype of two mouse models of inherited retinal diseases. Our data support the use of split intein-mediated protein trans-splicing in combination with AAV subretinal delivery for gene therapy of inherited blindness due to mutations in large genes.
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Affiliation(s)
- Patrizia Tornabene
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Ivana Trapani
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy.,Medical Genetics, Department of Translational Medicine, Federico II University, 80131 Naples, Italy
| | - Renato Minopoli
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Miriam Centrulo
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Mariangela Lupo
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Sonia de Simone
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Paola Tiberi
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Fabio Dell'Aquila
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Elena Marrocco
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Carolina Iodice
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Antonella Iuliano
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Carlo Gesualdo
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania L. Vanvitelli, 80131 Naples, Italy
| | - Settimio Rossi
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania L. Vanvitelli, 80131 Naples, Italy
| | - Laura Giaquinto
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Silvia Albert
- Department of Human Genetics and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 Nijmegen, Netherlands
| | - Carel B Hoyng
- Department of Ophthalmology and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 Nijmegen, Netherlands
| | - Elena Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Frans P M Cremers
- Department of Ophthalmology and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525 Nijmegen, Netherlands
| | - Enrico M Surace
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy.,Medical Genetics, Department of Translational Medicine, Federico II University, 80131 Naples, Italy
| | - Francesca Simonelli
- Eye Clinic, Multidisciplinary Department of Medical, Surgical and Dental Sciences, University of Campania L. Vanvitelli, 80131 Naples, Italy
| | - Maria A De Matteis
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy.,Department of Molecular Medicine and Medical Biotechnology, Federico II University, 80131 Naples, Italy
| | - Roman Polishchuk
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Alberto Auricchio
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy. .,Department of Advanced Biomedicine, Federico II University, 80131 Naples, Italy
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Hair Cell Transduction Efficiency of Single- and Dual-AAV Serotypes in Adult Murine Cochleae. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2020; 17:1167-1177. [PMID: 32518805 PMCID: PMC7270144 DOI: 10.1016/j.omtm.2020.05.007] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 05/07/2020] [Indexed: 01/03/2023]
Abstract
Gene delivery is a key component for the treatment of genetic hearing loss. To date, a myriad of adeno-associated virus (AAV) serotypes and surgical approaches have been employed to deliver transgenes to cochlear hair cells, but the efficacy of dual transduction remains unclear. Herein, we investigated cellular tropism of single injections of AAV serotype 1 (AAV1), AAV2, AAV8, AAV9, and Anc80L65, and quantitated dual-vector co-transduction rates following co-injection of AAV2 and AAV9 vectors in adult murine cochlea. We used the combined round window membrane and canal fenestration (RWM+CF) injection technique for vector delivery. Single AAV2 injections were most robust and transduced 96.7% ± 1.1% of inner hair cells (IHCs) and 83.9% ± 2.0% of outer hair cells (OHCs) throughout the cochlea without causing hearing impairment or hair cell loss. Dual AAV2 injection co-transduced 96.9% ± 1.7% of IHCs and 65.6% ± 8.95% of OHCs. Together, RWM+CF-injected single or dual AAV2 provides the highest auditory hair cell transduction efficiency of the AAV serotypes we studied. These findings broaden the application of cochlear gene therapy targeting hair cells.
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McClements ME, Barnard AR, Charbel Issa P, MacLaren RE. Assessment of AAV Dual Vector Safety in the Abca4-/- Mouse Model of Stargardt Disease. Transl Vis Sci Technol 2020; 9:20. [PMID: 32724727 PMCID: PMC7115835 DOI: 10.1167/tvst.9.7.20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2020] [Accepted: 04/19/2020] [Indexed: 12/19/2022] Open
Abstract
Purpose Adeno-associated viral (AAV) gene therapy treatment for Stargardt disease currently requires a dual vector approach owing to the size of the ATP-binding cassette transporter family member gene (ABCA4). The nature of the dual vector system creates the potential for adverse events. Here we have investigated an overlapping adeno-associated viral ABCA4 dual vector system for signs of toxicity in Abca4-/- mice as a prelude to dual vector first in human clinical trials. Methods Abca4-/- mice received a subretinal injection of a 1:1 5':3' dual vector mix; 5' vector only; 3 ' vector only; a GFP reporter vector; or diluent only (sham). All vectors were adeno-associated virus-8 Y733F. Mice were subsequently assessed for signs of toxicity as measured by loss in retinal structure by optical coherence tomography and retinal function by electroretinography up to 6 months after injection. Results Subretinal delivery of the dual vector system and its comprising parts induced no structural or functional changes relative to paired uninjected eyes beyond those observed in the sham control cohort. Histologic changes were limited to the superior retina where the injection was performed. Electroretinography analysis confirmed the dual vector system inferred no functional changes beyond those observed in the sham control cohort. Conclusions An optimized overlapping dual vector system for the treatment of Stargardt disease shows no additional signs of toxicity beyond those observed from a sham injection. Translational Relevance This presentation of safety of a dual vector system for the treatment of Stargardt disease encourages its future use in clinical trial.
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Affiliation(s)
- Michelle E. McClements
- University of Oxford, Nuffield Department of Ophthalmology, Clinical Neurosciences, Oxford, UK
| | - Alun R. Barnard
- University of Oxford, Nuffield Department of Ophthalmology, Clinical Neurosciences, Oxford, UK
| | | | - Robert E. MacLaren
- University of Oxford, Nuffield Department of Ophthalmology, Clinical Neurosciences, Oxford, UK
- Oxford Eye Hospital, Oxford, UK
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36
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Reynaud-Dulaurier R, Benegiamo G, Marrocco E, Al-Tannir R, Surace EM, Auwerx J, Decressac M. Gene replacement therapy provides benefit in an adult mouse model of Leigh syndrome. Brain 2020; 143:1686-1696. [DOI: 10.1093/brain/awaa105] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 01/24/2020] [Accepted: 02/12/2020] [Indexed: 01/10/2023] Open
Abstract
Abstract
Mutations in nuclear-encoded mitochondrial genes are responsible for a broad spectrum of disorders among which Leigh syndrome is the most common in infancy. No effective therapies are available for this severe disease mainly because of the limited capabilities of the standard adeno-associated viral (AAV) vectors to transduce both peripheral organs and the CNS when injected systemically in adults. Here, we used the brain-penetrating AAV-PHP.B vector to reinstate gene expression in the Ndufs4 knockout mouse model of Leigh syndrome. Intravenous delivery of an AAV.PHP.B-Ndufs4 vector in 1-month-old knockout mice restored mitochondrial complex I activity in several organs including the CNS. This gene replacement strategy extended lifespan, rescued metabolic parameters, provided behavioural improvement, and corrected the pathological phenotype in the brain, retina, and heart of Ndufs4 knockout mice. These results provide a robust proof that gene therapy strategies targeting multiple organs can rescue fatal neurometabolic disorders with CNS involvement.
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Affiliation(s)
- Robin Reynaud-Dulaurier
- Université Grenoble Alpes, Inserm, U1216, Grenoble Institut des Neurosciences, 38000 Grenoble, France
| | - Giorgia Benegiamo
- Laboratory for Integrative and Systems Physiology, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Elena Marrocco
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
| | - Racha Al-Tannir
- Université Grenoble Alpes, Inserm, U1216, Grenoble Institut des Neurosciences, 38000 Grenoble, France
| | - Enrico Maria Surace
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
- Medical Genetics, Department of Translational Medicine, Federico II University, 80131 Naples, Italy
| | - Johan Auwerx
- Laboratory for Integrative and Systems Physiology, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Michael Decressac
- Université Grenoble Alpes, Inserm, U1216, Grenoble Institut des Neurosciences, 38000 Grenoble, France
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy
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Nitzahn M, Allegri G, Khoja S, Truong B, Makris G, Häberle J, Lipshutz GS. Split AAV-Mediated Gene Therapy Restores Ureagenesis in a Murine Model of Carbamoyl Phosphate Synthetase 1 Deficiency. Mol Ther 2020; 28:1717-1730. [PMID: 32359471 DOI: 10.1016/j.ymthe.2020.04.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 02/25/2020] [Accepted: 04/09/2020] [Indexed: 02/07/2023] Open
Abstract
The urea cycle enzyme carbamoyl phosphate synthetase 1 (CPS1) catalyzes the initial step of the urea cycle; bi-allelic mutations typically present with hyperammonemia, vomiting, ataxia, lethargy progressing into coma, and death due to brain edema if ineffectively treated. The enzyme deficiency is particularly difficult to treat; early recognition is essential to minimize injury to the brain. Even under optimal conditions, therapeutic interventions are of limited scope and efficacy, with most patients developing long-term neurologic sequelae. One significant encumberment to gene therapeutic development is the size of the CPS1 cDNA, which, at 4.5 kb, nears the packaging capacity of adeno-associated virus (AAV). Herein we developed a split AAV (sAAV)-based approach, packaging the large transgene and its regulatory cassette into two separate vectors, thereby delivering therapeutic CPS1 by a dual vector system with testing in a murine model of the disorder. Cps1-deficient mice treated with sAAVs survive long-term with markedly improved ammonia levels, diminished dysregulation of circulating amino acids, and increased hepatic CPS1 expression and activity. In response to acute ammonia challenging, sAAV-treated female mice rapidly incorporated nitrogen into urea. This study demonstrates the first proof-of-principle that sAAV-mediated therapy is a viable, potentially clinically translatable approach to CPS1 deficiency, a devastating urea cycle disorder.
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Affiliation(s)
- Matthew Nitzahn
- Molecular Biology Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Gabriella Allegri
- Division of Metabolism and Children's Research Center, University Children's Hospital, Zurich, Switzerland
| | - Suhail Khoja
- Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Brian Truong
- Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Georgios Makris
- Division of Metabolism and Children's Research Center, University Children's Hospital, Zurich, Switzerland
| | - Johannes Häberle
- Division of Metabolism and Children's Research Center, University Children's Hospital, Zurich, Switzerland
| | - Gerald S Lipshutz
- Molecular Biology Institute, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Department of Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Molecular and Medical Pharmacology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Department of Psychiatry, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Intellectual and Developmental Disabilities Research Center, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA; Semel Institute for Neuroscience, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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Daga S, Donati F, Capitani K, Croci S, Tita R, Giliberti A, Valentino F, Benetti E, Fallerini C, Niccheri F, Baldassarri M, Mencarelli MA, Frullanti E, Furini S, Conticello SG, Renieri A, Pinto AM. New frontiers to cure Alport syndrome: COL4A3 and COL4A5 gene editing in podocyte-lineage cells. Eur J Hum Genet 2020; 28:480-490. [PMID: 31754267 PMCID: PMC7080842 DOI: 10.1038/s41431-019-0537-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 10/09/2019] [Accepted: 10/13/2019] [Indexed: 01/20/2023] Open
Abstract
Alport syndrome (AS) is an inherited genetic disorder characterized by range of alterations from glomerular basement membrane abnormalities up to end-stage renal disease. Pathogenic variants in the collagen α3, α4, and α5 encoding genes are causative both of the autosomal dominant and of the X-linked forms of AS. Podocytes are the only renal cells that are able to produce the COL(IV)a3-a4a5 heterotrimer. We have previously demonstrated how it is possible to isolate podocyte-lineage cells from urine of patients, providing an easily accessible cellular model closer to the podocytes' physiological conditions. Taking advantage of disease-relevant cell lines, we employed a two-plasmid approach in order to achieve a beneficial and stable variant-specific correction using CRISPR/Cas9 genome editing. One plasmid carries a Donor DNA and a reporter system mCherry/GFP to track the activity of Cas9 in cells. The other plasmid carries a self-cleaving SpCas9 and the variant-specific sgRNA. We have analyzed two stable podocyte-lineage cell lines, harboring a variant in the X-linked COL4A5 (p.(Gly624Asp)) and in the autosomal COL4A3 gene (p.(Gly856Glu)). We have achieved reversion of variants greater than 40% with undesired insertions/deletions lower than 15%. Overall, we have demonstrated a new gene therapy approach directly on patients' cells, key players of Alport pathogenesis, and we have reverted COL4 causative variants towards the wild type state. These results, in combination with preclinical models, could open new frontiers in the management and the treatment of the disorder.
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Affiliation(s)
- Sergio Daga
- 0000 0004 1757 4641grid.9024.fMedical Genetics, University of Siena, Siena, Italy
| | - Francesco Donati
- Core Research Laboratory, ISPRO, Florence, Italy ,0000 0004 1757 4641grid.9024.fDepartment of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Katia Capitani
- Core Research Laboratory, ISPRO, Florence, Italy ,0000 0004 1757 4641grid.9024.fDepartment of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Susanna Croci
- 0000 0004 1757 4641grid.9024.fMedical Genetics, University of Siena, Siena, Italy
| | - Rossella Tita
- 0000 0004 1759 0844grid.411477.0Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Annarita Giliberti
- 0000 0004 1757 4641grid.9024.fMedical Genetics, University of Siena, Siena, Italy
| | - Floriana Valentino
- 0000 0004 1757 4641grid.9024.fMedical Genetics, University of Siena, Siena, Italy
| | - Elisa Benetti
- 0000 0004 1757 4641grid.9024.fMedical Genetics, University of Siena, Siena, Italy
| | - Chiara Fallerini
- 0000 0004 1757 4641grid.9024.fMedical Genetics, University of Siena, Siena, Italy
| | | | - Margherita Baldassarri
- 0000 0004 1759 0844grid.411477.0Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | | | - Elisa Frullanti
- 0000 0004 1757 4641grid.9024.fMedical Genetics, University of Siena, Siena, Italy
| | - Simone Furini
- 0000 0004 1757 4641grid.9024.fDepartment of Medical Biotechnologies, University of Siena, Siena, Italy
| | | | - Alessandra Renieri
- 0000 0004 1757 4641grid.9024.fMedical Genetics, University of Siena, Siena, Italy ,0000 0004 1759 0844grid.411477.0Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Anna Maria Pinto
- 0000 0004 1759 0844grid.411477.0Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
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Trapani I, Auricchio A. Has retinal gene therapy come of age? From bench to bedside and back to bench. Hum Mol Genet 2020; 28:R108-R118. [PMID: 31238338 PMCID: PMC6797000 DOI: 10.1093/hmg/ddz130] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2019] [Revised: 04/24/2019] [Accepted: 06/07/2019] [Indexed: 02/06/2023] Open
Abstract
Retinal gene therapy has advanced considerably in the past three decades. Initial efforts have been devoted to comprehensively explore and optimize the transduction abilities of gene delivery vectors, define the appropriate intraocular administration routes and obtain evidence of efficacy in animal models of inherited retinal diseases (IRDs). Successful translation in clinical trials of the initial promising proof-of-concept studies led to the important milestone of the first approved product for retinal gene therapy in both US and Europe. The unprecedented clinical development observed during the last decade in the field is however highlighting new challenges that will need to be overcome to bring gene therapy to fruition to a larger patient population within and beyond the realm of IRDs.
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Affiliation(s)
- Ivana Trapani
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy.,Medical Genetics, Department of Translational Medicine, Federico II University, Naples, Italy
| | - Alberto Auricchio
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy.,Department of Advanced Biomedicine, Federico II University, Naples, Italy
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Barone F, Muscatello LV, Ventrella D, Elmi A, Romagnoli N, Mandrioli L, Maya-Vetencourt JF, Bombardi C, Mete M, Sarli G, Benfenati F, Pertile G, Bacci ML. The porcine iodoacetic acid model of retinal degeneration: Morpho-functional characterization of the visual system. Exp Eye Res 2020; 193:107979. [PMID: 32087230 DOI: 10.1016/j.exer.2020.107979] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 02/13/2020] [Accepted: 02/16/2020] [Indexed: 10/25/2022]
Abstract
Porcine models of ophthalmological diseases are often used in pre-clinical translational studies due to pigs' similarities to humans. In particular, the iodoacetic acid (IAA) model of photoreceptor degeneration seems to mimic well the endstage phenotype of human pathologies as retinitis pigmentosa and age-related macular degeneration, with high potential for prosthesis/retinal devices testing. IAA is capable of inducing photoreceptor death by blockage of glycolysis, and its effects on the retina have been described. Nonetheless, up to date, literature lacks of a comprehensive morpho-functional characterization of the entire visual system of this model. This gap is particularly critical for prosthesis testing as inner retinal structures and optic pathways must be preserved to elicit cortical responses and restore vision. In this study, we investigated the functional and anatomical features of the visual system of IAA-treated pigs and compared them to control animals. IAA was administered intravenously at 12 mg/kg; control animals received saline solution (NaCl 0.9% w/v). Electrophysiological analyses included full-field (ffERGs) and pattern (PERGs) electroretinograms and flash visually evoked potentials (fVEPs). Histological evaluations were performed on the retina and the optic pathways and included thickness of the different retinal layers, ganglion cells count, and immunohistochemistry for microglial cells, macroglial cells, and oligodendrocytes. The histological results indicate that IAA treatment does not affect the morphology of the inner retina and optic pathways. Electrophysiology confirms the selective rod and partial cone degeneration, but is ambiguous as to the functionality of the optic pathways, seemingly preserved as indicated by the still detectable fVEPs. Overall, the work ameliorates the characterization of such rapid and cost-effective model, providing more strength and reliability for future pre-clinical translational trials.
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Affiliation(s)
- Francesca Barone
- National Eye Institute, National Institute of Health, 10 Center Dr, Bethesda, 20814, MD, USA; Ophthalmology Department, Sacro Cuore Hospital - Don Calabria, Via Don A. Sempreboni 5, Negrar, 37024, VR, Italy
| | - Luisa Vera Muscatello
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Domenico Ventrella
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy.
| | - Alberto Elmi
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Noemi Romagnoli
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Luciana Mandrioli
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Josè Fernando Maya-Vetencourt
- Center for Synaptic Neuroscience and Technology, Italian Institute of Technology, Via Morego 30, Genova, 16163, GE, Italy; Department of Biology, University of Pisa, Via Alessandro Volta 4Bis, Pisa, 56126, PI, Italy
| | - Cristiano Bombardi
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Maurizio Mete
- Ophthalmology Department, Sacro Cuore Hospital - Don Calabria, Via Don A. Sempreboni 5, Negrar, 37024, VR, Italy
| | - Giuseppe Sarli
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
| | - Fabio Benfenati
- Center for Synaptic Neuroscience and Technology, Italian Institute of Technology, Via Morego 30, Genova, 16163, GE, Italy; Department of Experimental Medicine, University of Genoa, Via Leon Battista Alberti 2, Genova, 16132, GE, Italy
| | - Grazia Pertile
- Ophthalmology Department, Sacro Cuore Hospital - Don Calabria, Via Don A. Sempreboni 5, Negrar, 37024, VR, Italy
| | - Maria Laura Bacci
- Department of Veterinary Medical Sciences, Alma Mater Studiorum Univerisity of Bologna, Via Tolara di Sopra 50, Ozzano dell'Emilia, 40064, BO, Italy
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Tornabene P, Trapani I. Can Adeno-Associated Viral Vectors Deliver Effectively Large Genes? Hum Gene Ther 2020; 31:47-56. [DOI: 10.1089/hum.2019.220] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Patrizia Tornabene
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
- Medical Genetics, Department of Translational Medicine, Federico II University, Naples, Italy
| | - Ivana Trapani
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy
- Medical Genetics, Department of Translational Medicine, Federico II University, Naples, Italy
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Ataluren for the Treatment of Usher Syndrome 2A Caused by Nonsense Mutations. Int J Mol Sci 2019; 20:ijms20246274. [PMID: 31842393 PMCID: PMC6940777 DOI: 10.3390/ijms20246274] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 12/05/2019] [Accepted: 12/10/2019] [Indexed: 12/18/2022] Open
Abstract
The identification of genetic defects that underlie inherited retinal diseases (IRDs) paves the way for the development of therapeutic strategies. Nonsense mutations caused approximately 12% of all IRD cases, resulting in a premature termination codon (PTC). Therefore, an approach that targets nonsense mutations could be a promising pharmacogenetic strategy for the treatment of IRDs. Small molecules (translational read-through inducing drugs; TRIDs) have the potential to mediate the read-through of nonsense mutations by inducing expression of the full-length protein. We provide novel data on the read-through efficacy of Ataluren on a nonsense mutation in the Usher syndrome gene USH2A that causes deaf-blindness in humans. We demonstrate Ataluren´s efficacy in both transiently USH2AG3142*-transfected HEK293T cells and patient-derived fibroblasts by restoring USH2A protein expression. Furthermore, we observed enhanced ciliogenesis in patient-derived fibroblasts after treatment with TRIDs, thereby restoring a phenotype that is similar to that found in healthy donors. In light of recent findings, we validated Ataluren´s efficacy to induce read-through on a nonsense mutation in USH2A-related IRD. In line with published data, our findings support the use of patient-derived fibroblasts as a platform for the validation of preclinical therapies. The excellent biocompatibility combined with sustained read-through efficacy makes Ataluren an ideal TRID for treating nonsense mutations based IRDs.
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Huckenpahler AL, Carroll J, Salmon AE, Sajdak BS, Mastey RR, Allen KP, Kaplan HJ, McCall MA. Noninvasive Imaging and Correlative Histology of Cone Photoreceptor Structure in the Pig Retina. Transl Vis Sci Technol 2019; 8:38. [PMID: 31867139 PMCID: PMC6922271 DOI: 10.1167/tvst.8.6.38] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Accepted: 10/04/2019] [Indexed: 12/16/2022] Open
Abstract
PURPOSE To evaluate different methods of studying cone photoreceptor structure in wild-type (WT) and transgenic pigs carrying the human rhodopsin P23H mutant gene (TgP23H). METHODS For in vivo imaging, pigs were anesthetized with tiletamine-zolazepam and isoflurane and given lidocaine-bupivacaine retrobulbar injections. Stay sutures and a custom head mount were used to hold and steer the head for adaptive optics scanning light ophthalmoscopy (AOSLO). Six WT and TgP23H littermates were imaged at postnatal day 30 (P30), P90, and P180 with AOSLO and optical coherence tomography (OCT), and two additional sets of littermates were imaged at P3 and P15 with OCT only. AOSLO imaging and correlative differential interference contrast microscopy were performed on a P240 WT pig and on WT and TgP23H littermates at P30 and P180. RESULTS AOSLO cone density generally underestimates histology density (mean difference ± SD = 24.8% ± 21.4%). The intensity of the outer retinal hyperreflective OCT band attributed to photoreceptors is attenuated in TgP23H pigs at all ages. In contrast, AOSLO images show cones that retain inner and outer segments through P180. At retinal locations outside the visual streak, TgP23H pigs show a heterogeneous degenerating cone mosaic by using two criteria: variable contrast on a split detector AOSLO and high reflectivity on a confocal AOSLO. CONCLUSIONS AOSLO reveals that the cone mosaic is similar to ex vivo histology. Its use as a noninvasive tool will enable observation of morphologic changes that arise in the cone mosaic of TgP23H pigs over time. TRANSLATIONAL RELEVANCE Pigs are widely used for translational studies, and the ability to noninvasively assess cellular changes in the cone mosaic will facilitate more detailed investigations of new retinal disease models as well as outcomes of potential therapies.
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Affiliation(s)
- Alison L Huckenpahler
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Joseph Carroll
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Alexander E Salmon
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Benjamin S Sajdak
- Department of Cell Biology, Neurobiology & Anatomy, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Rebecca R Mastey
- Department of Ophthalmology & Visual Sciences, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Kenneth P Allen
- Biomedical Resource Center, Medical College of Wisconsin, Milwaukee, WI, USA
- Department of Microbiology & Immunology, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Henry J Kaplan
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY, USA
| | - Maureen A McCall
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY, USA
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY, USA
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Dyka FM, Molday LL, Chiodo VA, Molday RS, Hauswirth WW. Dual ABCA4-AAV Vector Treatment Reduces Pathogenic Retinal A2E Accumulation in a Mouse Model of Autosomal Recessive Stargardt Disease. Hum Gene Ther 2019; 30:1361-1370. [PMID: 31418294 DOI: 10.1089/hum.2019.132] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Autosomal recessive Stargardt disease is the most common inherited macular degeneration in humans. It is caused by mutations in the retina-specific ATP binding cassette transporter A4 (ABCA4) that is essential for the clearance of all-trans-retinal from photoreceptor cells. Loss of this function results in the accumulation of toxic bisretinoids in the outer segment disk membranes and their subsequent transfer into adjacent retinal pigment epithelium (RPE) cells. This ultimately leads to the Stargardt disease phenotype of increased retinal autofluorescence and progressive RPE and photoreceptor cell loss. Adeno-associated virus (AAV) vectors have been widely used in gene therapeutic applications, but their limited cDNA packaging capacity of ∼4.5 kb has impeded their use for transgenes exceeding this limit. AAV dual vectors were developed to overcome this size restriction. In this study, we have evaluated the in vitro expression of ABCA4 using three options: overlap, transplicing, and hybrid ABCA4 dual vector systems. The hybrid system was the most efficient of these dual vector alternatives and used to express the full-length ABCA4 in Abca4-/- mice. The full-length ABCA4 protein correctly localized to photoreceptor outer segments. Moreover, treatment of Abca4-/- mice with this ABCA4 hybrid dual vector system resulted in a reduced accumulation of the lipofuscin/N-retinylidene-N-retinylethanolamine (A2E) autofluorescence in vivo, and retinal A2E quantification supported these findings. These results show that the hybrid AAV dual vector option is both safe and therapeutic in mice, and the delivered ABCA4 transgene is functional and has a significant effect on reducing A2E accumulation in the Abca4-/- mouse model of Stargardt disease.
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Affiliation(s)
- Frank M Dyka
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida
| | - Laurie L Molday
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Vince A Chiodo
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida
| | - Robert S Molday
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - William W Hauswirth
- Department of Ophthalmology, College of Medicine, University of Florida, Gainesville, Florida
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Vázquez-Domínguez I, Garanto A, Collin RWJ. Molecular Therapies for Inherited Retinal Diseases-Current Standing, Opportunities and Challenges. Genes (Basel) 2019; 10:genes10090654. [PMID: 31466352 PMCID: PMC6770110 DOI: 10.3390/genes10090654] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/23/2019] [Accepted: 08/26/2019] [Indexed: 12/15/2022] Open
Abstract
Inherited retinal diseases (IRDs) are both genetically and clinically highly heterogeneous and have long been considered incurable. Following the successful development of a gene augmentation therapy for biallelic RPE65-associated IRD, this view has changed. As a result, many different therapeutic approaches are currently being developed, in particular a large variety of molecular therapies. These are depending on the severity of the retinal degeneration, knowledge of the pathophysiological mechanism underlying each subtype of IRD, and the therapeutic target molecule. DNA therapies include approaches such as gene augmentation therapy, genome editing and optogenetics. For some genetic subtypes of IRD, RNA therapies and compound therapies have also shown considerable therapeutic potential. In this review, we summarize the current state-of-the-art of various therapeutic approaches, including the pros and cons of each strategy, and outline the future challenges that lie ahead in the combat against IRDs.
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Affiliation(s)
- Irene Vázquez-Domínguez
- Department of Human Genetics and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525GA Nijmegen, The Netherlands
| | - Alejandro Garanto
- Department of Human Genetics and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525GA Nijmegen, The Netherlands.
| | - Rob W J Collin
- Department of Human Genetics and Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, 6525GA Nijmegen, The Netherlands.
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46
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Trapani I. Adeno-Associated Viral Vectors as a Tool for Large Gene Delivery to the Retina. Genes (Basel) 2019; 10:genes10040287. [PMID: 30970639 PMCID: PMC6523333 DOI: 10.3390/genes10040287] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Revised: 03/26/2019] [Accepted: 04/05/2019] [Indexed: 12/26/2022] Open
Abstract
Gene therapy using adeno-associated viral (AAV) vectors currently represents the most promising approach for the treatment of many inherited retinal diseases (IRDs), given AAV's ability to efficiently deliver therapeutic genes to both photoreceptors and retinal pigment epithelium, and their excellent safety and efficacy profiles in humans. However, one of the main obstacles to widespread AAV application is their limited packaging capacity, which precludes their use from the treatment of IRDs which are caused by mutations in genes whose coding sequence exceeds 5 kb. Therefore, in recent years, considerable effort has been made to identify strategies to increase the transfer capacity of AAV vectors. This review will discuss these new developed strategies, highlighting the advancements as well as the limitations that the field has still to overcome to finally expand the applicability of AAV vectors to IRDs due to mutations in large genes.
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Affiliation(s)
- Ivana Trapani
- Telethon Institute of Genetics and Medicine (TIGEM), 80078 Pozzuoli, Italy.
- Medical Genetics, Department of Translational Medicine, Federico II University, 80131 Naples, Italy.
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Abstract
Adeno-associated virus (AAV)-mediated gene therapy has evolved from bench to bedside, and now is the therapy of choice for certain inherited diseases. However, the small packaging capacity of AAV vectors prevents this technique from treating genetic diseases with mutations of large genes. Multiple strategies, including split AAV gene delivery and oversized AAV gene delivery, have been explored to deliver large gene expression cassettes. These strategies have gained some success in animal experiments. In this chapter, we review the progress of AAV-mediated delivery of large expression cassettes. We also review using AAV to deliver multiple transgenes.
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Affiliation(s)
- Aman Patel
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Junling Zhao
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO, USA
| | - Dongsheng Duan
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO, USA
- Department of Biomedical Sciences, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
- Department of Neurology, School of Medicine, University of Missouri, Columbia, MO, USA
- Department of Bioengineering, University of Missouri, Columbia, MO, USA
| | - Yi Lai
- Department of Molecular Microbiology and Immunology, School of Medicine, University of Missouri, Columbia, MO, USA.
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48
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McClements ME, Barnard AR, Singh MS, Charbel Issa P, Jiang Z, Radu RA, MacLaren RE. An AAV Dual Vector Strategy Ameliorates the Stargardt Phenotype in Adult Abca4-/- Mice. Hum Gene Ther 2018; 30:590-600. [PMID: 30381971 DOI: 10.1089/hum.2018.156] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The recent approval in the United States of the first adeno-associated viral (AAV) vector for the treatment of an inherited retinal degeneration validates this approach for the treatment of many other diseases. A major limiting factor continues to be the size restriction of the AAV transgene at under 5 kb. Stargardt disease is the most prevalent form of recessively inherited blindness and is caused by mutations in ABCA4, the gene that codes for ATP-binding cassette transporter protein family member 4, which has a coding sequence length of 6.8 kb. Dual vector approaches increase the capacity of AAV gene therapy, but at the cost of substantially reduced levels of target protein, which may be insufficient to achieve a therapeutic effect. Here we show that the efficacy of recombination of dual vectors is dependent on the length of DNA overlap between two transgenes. With optimized recombination, full-length ABCA4 protein is expressed in the photoreceptor outer segments of Abca4-/- mice at levels sufficient to reduce bisretinoid formation and correct the autofluorescent phenotype. These observations support a dual vector approach in future clinical trials using AAV gene therapy to treat Stargardt disease.
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Affiliation(s)
- Michelle E McClements
- 1 Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Alun R Barnard
- 1 Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | | | - Peter Charbel Issa
- 1 Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,3 Oxford Eye Hospital, Oxford, United Kingdom
| | - Zhichun Jiang
- 4 Stein Eye Institute, Department of Ophthalmology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California
| | - Roxana A Radu
- 4 Stein Eye Institute, Department of Ophthalmology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California
| | - Robert E MacLaren
- 1 Nuffield Laboratory of Ophthalmology, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,3 Oxford Eye Hospital, Oxford, United Kingdom
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Abstract
Gene therapy for genetic hearing loss is a nascent field with just a handful of studies published to date that demonstrate proof‐of‐concept recovery of auditory function (reviewed in Ahmed et al, 2017; Lustig & Akil, 2018). One challenge that faces the inner ear field, as well as the broader gene therapy field, is the need to deliver large gene sequences despite the limited genetic capacity (~4.5 kB) of delivery vehicles such as adeno‐associated viral vectors (AAV). In this issue, Al‐Moyed et al have overcome this conundrum by using two AAV vectors to deliver the coding sequence for otoferlin, which is ~6 kB. With dual‐AAV delivery of split otoferlin and a trans‐splicing approach, they demonstrate recombination of full‐length otoferlin in sensory hair cells of the inner ear, enabling partial restoration of auditory function in deaf, otoferlin‐null mice.
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Affiliation(s)
- Jeffrey R Holt
- Department of Otolaryngology, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
| | - Gwenaelle Sg Geleoc
- Department of Otolaryngology, Boston Children's Hospital and Harvard Medical School, Boston, MA, USA
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50
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Trapani I, Auricchio A. Seeing the Light after 25 Years of Retinal Gene Therapy. Trends Mol Med 2018; 24:669-681. [PMID: 29983335 DOI: 10.1016/j.molmed.2018.06.006] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 05/31/2018] [Accepted: 06/11/2018] [Indexed: 12/25/2022]
Abstract
The retina has been at the forefront of translational gene therapy. Proof-of-concept that gene therapy could restore vision in a large animal led to the initiation of the first successful clinical trials and, in turn, to the recent approval of the first gene therapy product for an ocular disease. As dozens of clinical trials of retinal gene therapy have begun, new challenges are identified, which include delivery of large genes, counteracting gain-of-function mutations, and safe and effective gene transfer to diseased retinas. Advancements in vector design, improvements of delivery routes, and selection of optimal timing for intervention will contribute to extend the initial success of retinal gene therapy to an increasing number of inherited blinding conditions.
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Affiliation(s)
- Ivana Trapani
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy; Medical Genetics, Department of Translational Medicine, Federico II University, Naples, Italy.
| | - Alberto Auricchio
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Italy; Department of Advanced Biomedicine, Federico II University, Naples, Italy.
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