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Sechrest ER, Barbera RJ, Ma X, Dyka F, Ahn J, Brothers BA, Cahill ME, Hall I, Baehr W, Deng WT. Expression of red/green-cone opsin mutants K82E, P187S, M273K result in unique pathobiological perturbations to cone structure and function. Front Neurosci 2024; 18:1368089. [PMID: 38410159 PMCID: PMC10895044 DOI: 10.3389/fnins.2024.1368089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Accepted: 01/23/2024] [Indexed: 02/28/2024] Open
Abstract
Long-and middle-wavelength cone photoreceptors, which are responsible for our visual acuity and color vision, comprise ~95% of our total cone population and are concentrated in the fovea of our retina. Previously, we characterized the disease mechanisms of the L/M-cone opsin missense mutations N94K, W177R, P307L, R330Q and G338E, all of which are associated with congenital blue cone monochromacy (BCM) or color-vision deficiency. Here, we used a similar viral vector-based gene delivery approach in M-opsin knockout mice to investigate the pathogenic consequences of the BCM or color-vision deficient associated L-cone opsin (OPN1LW) mutants K82E, P187S, and M273K. We investigated their subcellular localization, the pathogenic effects on cone structure, function, and cone viability. K82E mutants were detected predominately in cone outer segments, and its expression partially restored expression and correct localization of cone PDE6α' and cone transducin γ. As a result, K82E also demonstrated the ability to mediate cone light responses. In contrast, expression of P187S was minimally detected by either western blot or by immunohistochemistry, probably due to efficient degradation of the mutant protein. M273K cone opsin appeared to be misfolded as it was primarily localized to the cone inner segment and endoplasmic reticulum. Additionally, M273K did not restore the expression of cone PDE6α' and cone transducin γ in dorsal cone OS, presumably by its inability to bind 11-cis retinal. Consistent with the observed expression pattern, P187S and M273K cone opsin mutants were unable to mediate light responses. Moreover, expression of K82E, P187S, and M273K mutants reduced cone viability. Due to the distinct expression patterns and phenotypic differences of these mutants observed in vivo, we suggest that the pathobiological mechanisms of these mutants are distinct.
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Affiliation(s)
- Emily R. Sechrest
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, WV, United States
| | - Robert J. Barbera
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, WV, United States
| | - Xiaojie Ma
- Department of Ophthalmology, University of Florida, Gainesville, FL, United States
| | - Frank Dyka
- Department of Ophthalmology, University of Florida, Gainesville, FL, United States
| | - Junyeop Ahn
- Department of Chemistry, University of Virginia, Charlottesville, VA, United States
| | - Brooke A. Brothers
- Department of Biochemistry, West Virginia University, Morgantown, WV, United States
| | - Marion E. Cahill
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, WV, United States
- Department of Biology, West Virginia University, Morgantown, WV, United States
| | - Isaac Hall
- Department of Natural Sciences, Fairmont State University, Fairmont, WV, United States
| | - Wolfgang Baehr
- Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, UT, United States
- Department of Neurobiology and Anatomy, University of Utah Health Science Center, Salt Lake City, UT, United States
- Department of Biology, University of Utah, Salt Lake City, UT, United States
| | - Wen-Tao Deng
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, WV, United States
- Department of Biochemistry, West Virginia University, Morgantown, WV, United States
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2
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Keller WR, Picciano A, Wilson K, Xu J, Khasa H, Wendeler M. Rational downstream development for adeno-associated virus full/empty capsid separation - A streamlined methodology based on high-throughput screening and mechanistic modeling. J Chromatogr A 2024; 1716:464632. [PMID: 38219623 DOI: 10.1016/j.chroma.2024.464632] [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: 07/18/2023] [Revised: 01/03/2024] [Accepted: 01/04/2024] [Indexed: 01/16/2024]
Abstract
Recombinant adeno-associated virus (AAV) has emerged as one of the most promising systems for therapeutic gene delivery and has demonstrated clinical success in a wide range of genetic disorders. However, manufacturing of high-quality AAV in large amounts still remains a challenge. A significant difficulty for downstream processing is the need to remove empty capsids that are generated in all currently utilized expression systems and that represent product-related impurities that adversely affect safety and efficacy of AAV vectors. Empty and full capsids exhibit only subtle differences in surface charge and size, making chromatography-based separations highly challenging. Here, we present a rapid methodology for the systematic process development of the crucial AAV full/empty capsid separation on ion-exchange media based on high-throughput screening and mechanistic modeling. Two of the most commonly employed serotypes, AAV8 and AAV9, are used as case studies. First, high-throughput studies in filter-plate format are performed that allow the rapid and comprehensive study of binding and elution behavior of AAV on different resins, using different buffer systems, pH, salt conditions, and solution additives. Small amounts of separated empty and full AAV capsids are generated by iodixanol gradient centrifugation that allow studying the binding and elution behavior of the two vector species separately in miniaturized format. Process conditions that result in maximum differences in elution behavior between empty and full capsids are then transferred to benchtop chromatography systems that are used to generate calibration data for the estimation of steric mass-action isotherm and mass transport parameters for process simulation. The resulting column models are employed for in-silico process development that serves to enhance understanding of separation constraints and to identify optimized conditions for the removal of empty particles. Finally, optimized separation conditions are verified experimentally. The methodology presented in this work provides a systematic framework that affords mechanistic understanding of the crucial empty/full capsid separation and accelerates the development of a scalable AAV downstream process.
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Affiliation(s)
- William R Keller
- Purification Process Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, United States
| | - Angela Picciano
- Purification Process Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, United States
| | - Kelly Wilson
- Purification Process Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, United States
| | - Jin Xu
- Cell Culture and Fermentation Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, United States
| | - Harshit Khasa
- Analytical Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, United States
| | - Michaela Wendeler
- Purification Process Sciences, BioPharmaceuticals Development, R&D, AstraZeneca, Gaithersburg, United States.
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3
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Sechrest ER, Ma X, Cahill ME, Barbera RJ, Wang Y, Deng WT. Structural and functional rescue of cones carrying the most common cone opsin C203R missense mutation. JCI Insight 2024; 9:e172834. [PMID: 38060327 PMCID: PMC10906232 DOI: 10.1172/jci.insight.172834] [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: 06/06/2023] [Accepted: 12/05/2023] [Indexed: 01/24/2024] Open
Abstract
An arginine to cysteine substitution at amino acid position 203 (C203R) is the most common missense mutation in human cone opsin. Linked to color blindness and blue cone monochromacy (BCM), C203 is involved in a crucial disulfide bond required for proper folding. It has previously been postulated that expression of mutant C203R cone opsin exerts a toxic effect on cone photoreceptors, similar to some well-characterized missense mutations in rhodopsin that lead to protein misfolding. In this study, we generated and characterized a BCM mouse model carrying the equivalent C203R mutation (Opn1mwC198R Opn1sw-/-) to investigate the disease mechanism and develop a gene therapy approach for this disorder. Untreated Opn1mwC198R Opn1sw-/- cones phenocopied affected cones in human patients with the equivalent mutation, exhibiting shortened or absent cone outer segments and loss of function. We determined that gene augmentation targeting cones specifically yielded robust rescue of cone function and structure when Opn1mwC198R Opn1sw-/- mice were treated at early ages. Importantly, treated cones displayed elaborated outer segments and replenished expression of crucial cone phototransduction proteins. Interestingly, we were unable to detect OPN1MWC198R mutant opsin at any age. We believe this is the first proof-of-concept study exploring the efficacy of gene therapy in BCM associated with a C203R mutation.
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Affiliation(s)
- Emily R. Sechrest
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, West Virginia, USA
| | - Xiaojie Ma
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Marion E. Cahill
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, West Virginia, USA
- Department of Biology and
| | - Robert J. Barbera
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, West Virginia, USA
| | - Yixiao Wang
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Wen-Tao Deng
- Department of Ophthalmology and Visual Sciences, West Virginia University, Morgantown, West Virginia, USA
- Department of Biochemistry and Molecular Medicine, West Virginia University, Morgantown, West Virginia, USA
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4
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Lavoie RA, Zugates JT, Cheeseman AT, Teten MA, Ramesh S, Freeman JM, Swango S, Fitzpatrick J, Joshi A, Hollers B, Debebe Z, Lindgren TK, Kozak AN, Kondeti VK, Bright MK, Yearley EJ, Tracy A, Irwin JA, Guerrero M. Enrichment of adeno-associated virus serotype 5 full capsids by anion exchange chromatography with dual salt elution gradients. Biotechnol Bioeng 2023; 120:2953-2968. [PMID: 37256741 DOI: 10.1002/bit.28453] [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: 11/29/2022] [Revised: 05/03/2023] [Accepted: 05/18/2023] [Indexed: 06/02/2023]
Abstract
Adeno-associated virus-based gene therapies have demonstrated substantial therapeutic benefit for the treatment of genetic disorders. In manufacturing processes, viral capsids are produced with and without the encapsidated gene of interest. Capsids devoid of the gene of interest, or "empty" capsids, represent a product-related impurity. As a result, a robust and scalable method to enrich full capsids is crucial to provide patients with as much potentially active product as possible. Anion exchange chromatography has emerged as a highly utilized method for full capsid enrichment across many serotypes due to its ease of use, robustness, and scalability. However, achieving sufficient resolution between the full and empty capsids is not trivial. In this work, anion exchange chromatography was used to achieve empty and full capsid resolution for adeno-associated virus serotype 5. A salt gradient screen of multiple salts with varied valency and Hofmeister series properties was performed to determine optimal peak resolution and aggregate reduction. Dual salt effects were evaluated on the same product and process attributes to identify any synergies with the use of mixed ion gradients. The modified process provided as high as ≥75% AAV5 full capsids (≥3-fold enrichment based on the percent full in the feed stream) with near baseline separation of empty capsids and achieved an overall vector genome step yield of >65%.
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Affiliation(s)
| | | | | | - Matt A Teten
- BridgeBio Gene Therapy LLC, Raleigh, North Carolina, USA
| | | | | | - Summer Swango
- BridgeBio Gene Therapy LLC, Raleigh, North Carolina, USA
| | | | - Amod Joshi
- BridgeBio Gene Therapy LLC, Raleigh, North Carolina, USA
| | | | | | | | - Amber N Kozak
- BridgeBio Gene Therapy LLC, Raleigh, North Carolina, USA
| | | | - Mary K Bright
- BridgeBio Gene Therapy LLC, Raleigh, North Carolina, USA
| | - Eric J Yearley
- BridgeBio Gene Therapy LLC, Raleigh, North Carolina, USA
| | | | - Jacob A Irwin
- BridgeBio Gene Therapy LLC, Raleigh, North Carolina, USA
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5
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Lau SC, Grati M, Isgrig K, Sinan M, Calabro KR, Zhu J, Ishibashi Y, Ozgur Z, Wafa T, Belyantseva IA, Fitzgerald T, Friedman TB, Boye SL, Boye SE, Chien WW. Dual-AAV vector-mediated expression of MYO7A improves vestibular function in a mouse model of Usher syndrome 1B. Mol Ther Methods Clin Dev 2023; 30:534-545. [PMID: 37693946 PMCID: PMC10491803 DOI: 10.1016/j.omtm.2023.08.012] [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: 03/14/2023] [Accepted: 08/16/2023] [Indexed: 09/12/2023]
Abstract
Usher syndrome is the most common cause of deafness-blindness in the world. Usher syndrome type 1B (USH1B) is associated with mutations in MYO7A. Patients with USH1B experience deafness, blindness, and vestibular dysfunction. In this study, we applied adeno-associated virus (AAV)-mediated gene therapy to the shaker-1 (Myo7a4626SB/4626SB) mouse, a model of USH1B. The shaker-1 mouse has a nonsense mutation in Myo7a, is profoundly deaf throughout life, and has significant vestibular dysfunction. Because of the ∼6.7-kb size of the MYO7A cDNA, a dual-AAV approach was used for gene delivery, which involves splitting human MYO7A cDNA into 5' and 3' halves and cloning them into two separate AAV8(Y733F) vectors. When MYO7A cDNA was delivered to shaker-1 inner ears using the dual-AAV approach, cochlear hair cell survival was improved. However, stereocilium organization and auditory function were not improved. In contrast, in the vestibular system, dual-AAV-mediated MYO7A delivery significantly rescued hair cell stereocilium morphology and improved vestibular function, as reflected in a reduction of circling behavior and improved vestibular sensory-evoked potential (VsEP) thresholds. Our data indicate that dual-AAV-mediated MYO7A expression improves vestibular function in shaker-1 mice and supports further development of this approach for the treatment of disabling dizziness from vestibular dysfunction in USH1B patients.
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Affiliation(s)
- Samantha C. Lau
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Mhamed Grati
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kevin Isgrig
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Moaz Sinan
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Kaitlyn R. Calabro
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Jianliang Zhu
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Yasuko Ishibashi
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Zeynep Ozgur
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Talah Wafa
- Mouse Auditory Testing Core Facility, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Inna A. Belyantseva
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Tracy Fitzgerald
- Mouse Auditory Testing Core Facility, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Thomas B. Friedman
- Laboratory of Molecular Genetics, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sanford L. Boye
- Powell Gene Therapy Center, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Shannon E. Boye
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Wade W. Chien
- Inner Ear Gene Therapy Program, National Institute on Deafness and Other Communication Disorders, National Institutes of Health, Bethesda, MD 20892, USA
- Department of Otolaryngology – Head & Neck Surgery, Johns Hopkins School of Medicine, Baltimore, MD, USA
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6
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Mellen RW, Calabro KR, McCullough KT, Crosson SM, Cova ADL, Fajardo D, Xu E, Boye SL, Boye SE. Development of an AAV-CRISPR-Cas9-based treatment for dominant cone-rod dystrophy 6. Mol Ther Methods Clin Dev 2023; 30:48-64. [PMID: 37361352 PMCID: PMC10285452 DOI: 10.1016/j.omtm.2023.05.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 05/30/2023] [Indexed: 06/28/2023]
Abstract
Cone-rod dystrophy 6 (CORD6) is caused by gain-of-function mutations in the GUCY2D gene, which encodes retinal guanylate cyclase-1 (RetGC1). There are currently no treatments available for this autosomal dominant disease, which is characterized by severe, early-onset visual impairment. The purpose of our study was to develop an adeno-associated virus (AAV)-CRISPR-Cas9-based approach referred to as "ablate and replace" and evaluate its therapeutic potential in mouse models of CORD6. This two-vector system delivers (1) CRISPR-Cas9 targeted to the early coding sequence of the wild-type and mutant GUCY2D alleles and (2) a CRISPR-Cas9-resistant cDNA copy of GUCY2D ("hardened" GUCY2D). Together, these vectors knock out ("ablate") expression of endogenous RetGC1 in photoreceptors and supplement ("replace") a healthy copy of exogenous GUCY2D. First, we confirmed that ablation of mutant R838S GUCY2D was therapeutic in a transgenic mouse model of CORD6. Next, we established a proof of concept for "ablate and replace" and optimized vector doses in Gucy2e+/-:Gucy2f-/- and Gucy2f-/- mice, respectively. Finally, we confirmed that the "ablate and replace" approach stably preserved retinal structure and function in a novel knockin mouse model of CORD6, the RetGC1 (hR838S, hWT) mouse. Taken together, our results support further development of the "ablate and replace" approach for treatment of CORD6.
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Affiliation(s)
- Russell W. Mellen
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Kaitlyn R. Calabro
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - K. Tyler McCullough
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Sean M. Crosson
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Alejandro de la Cova
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Diego Fajardo
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Emily Xu
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Sanford L. Boye
- Powell Gene Therapy Center, Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Shannon E. Boye
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, Gainesville, FL, USA
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7
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Hellweg L, Edenhofer A, Barck L, Huppertz MC, Frei MS, Tarnawski M, Bergner A, Koch B, Johnsson K, Hiblot J. A general method for the development of multicolor biosensors with large dynamic ranges. Nat Chem Biol 2023; 19:1147-1157. [PMID: 37291200 PMCID: PMC10449634 DOI: 10.1038/s41589-023-01350-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 04/25/2023] [Indexed: 06/10/2023]
Abstract
Fluorescent biosensors enable the study of cell physiology with spatiotemporal resolution; yet, most biosensors suffer from relatively low dynamic ranges. Here, we introduce a family of designed Förster resonance energy transfer (FRET) pairs with near-quantitative FRET efficiencies based on the reversible interaction of fluorescent proteins with a fluorescently labeled HaloTag. These FRET pairs enabled the straightforward design of biosensors for calcium, ATP and NAD+ with unprecedented dynamic ranges. The color of each of these biosensors can be readily tuned by changing either the fluorescent protein or the synthetic fluorophore, which enables simultaneous monitoring of free NAD+ in different subcellular compartments following genotoxic stress. Minimal modifications of these biosensors furthermore allow their readout to be switched to fluorescence intensity, fluorescence lifetime or bioluminescence. These FRET pairs thus establish a new concept for the development of highly sensitive and tunable biosensors.
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Affiliation(s)
- Lars Hellweg
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Anna Edenhofer
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Lucas Barck
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Magnus-Carsten Huppertz
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Michelle S Frei
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Miroslaw Tarnawski
- Protein Expression and Characterization Facility, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Andrea Bergner
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Birgit Koch
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
| | - Kai Johnsson
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany
- Institute of Chemical Sciences and Engineering (ISIC), École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Julien Hiblot
- Department of Chemical Biology, Max Planck Institute for Medical Research, Heidelberg, Germany.
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8
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Chu W, Shastry S, Barbieri E, Prodromou R, Greback-Clarke P, Smith W, Moore B, Kilgore R, Cummings C, Pancorbo J, Gilleskie G, Daniele MA, Menegatti S. Peptide ligands for the affinity purification of adeno-associated viruses from HEK 293 cell lysates. Biotechnol Bioeng 2023; 120:2283-2300. [PMID: 37435968 PMCID: PMC10440015 DOI: 10.1002/bit.28495] [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: 02/21/2023] [Revised: 06/15/2023] [Accepted: 06/30/2023] [Indexed: 07/13/2023]
Abstract
Adeno-associated viruses (AAVs) are the vector of choice for delivering gene therapies that can cure inherited and acquired diseases. Clinical research on various AAV serotypes significantly increased in recent years alongside regulatory approvals of AAV-based therapies. The current AAV purification platform hinges on the capture step, for which several affinity resins are commercially available. These adsorbents rely on protein ligands-typically camelid antibodies-that provide high binding capacity and selectivity, but suffer from low biochemical stability and high cost, and impose harsh elution conditions (pH < 3) that can harm the transduction activity of recovered AAVs. Addressing these challenges, this study introduces peptide ligands that selectively capture AAVs and release them under mild conditions (pH = 6.0). The peptide sequences were identified by screening a focused library and modeled in silico against AAV serotypes 2 and 9 (AAV2 and AAV9) to select candidate ligands that target homologous sites at the interface of the VP1-VP2 and VP2-VP3 virion proteins with mild binding strength (KD ~ 10-5 -10- 6 M). Selected peptides were conjugated to Toyopearl resin and evaluated via binding studies against AAV2 and AAV9, demonstrating the ability to target both serotypes with values of dynamic binding capacity (DBC10% > 1013 vp/mL of resin) and product yields (~50%-80%) on par with commercial adsorbents. The peptide-based adsorbents were finally utilized to purify AAV2 from a HEK 293 cell lysate, affording high recovery (50%-80%), 80- to 400-fold reduction of host cell proteins (HCPs), and high transduction activity (up to 80%) of the purified viruses.
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Affiliation(s)
- Wenning Chu
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Shriarjun Shastry
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
- Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, North Carolina, USA
| | - Eduardo Barbieri
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Raphael Prodromou
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Paul Greback-Clarke
- Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, North Carolina, USA
| | - Will Smith
- Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, North Carolina, USA
| | - Brandyn Moore
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Ryan Kilgore
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Christopher Cummings
- Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, North Carolina, USA
| | - Jennifer Pancorbo
- Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, North Carolina, USA
| | - Gary Gilleskie
- Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, North Carolina, USA
| | - Michael A Daniele
- North Carolina Viral Vector Initiative in Research and Learning (NC-VVIRAL), North Carolina State University, Raleigh, North Carolina, USA
- Joint Department of Biomedical Engineering, North Carolina State University and University of North Carolina at Chapel Hill, Raleigh, North Carolina, USA
| | - Stefano Menegatti
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
- Biomanufacturing Training and Education Center (BTEC), North Carolina State University, Raleigh, North Carolina, USA
- North Carolina Viral Vector Initiative in Research and Learning (NC-VVIRAL), North Carolina State University, Raleigh, North Carolina, USA
- LigaTrap Technologies LLC, Raleigh, North Carolina, USA
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9
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Mietzsch M, Liu W, Ma K, Bennett A, Nelson AR, Gliwa K, Chipman P, Fu X, Bechler S, McKenna R, Viner R. Production and characterization of an AAV1-VP3-only capsid: An analytical benchmark standard. Mol Ther Methods Clin Dev 2023; 29:460-472. [PMID: 37273903 PMCID: PMC10238842 DOI: 10.1016/j.omtm.2023.05.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Accepted: 05/04/2023] [Indexed: 06/06/2023]
Abstract
Adeno-associated viruses (AAVs) are non-enveloped ssDNA icosahedral T = 1 viruses used as vectors for clinical gene delivery. Currently, there are over 200 AAV-related clinical trials and six approved biologics on the market. As such new analytical methods are continually being developed to characterize and monitor the quality and purity of manufactured AAV vectors, these include ion-exchange chromatography and Direct Mass Technology. However, these methods require homogeneous analytical standards with a high molecular weight standard comparable to the mass of an AAV capsid. Described here is the design, production, purification, characterization, and the cryo-electron microscopy structure of an AAV1-VP3-only capsid that fulfills this need as a calibrant to determine capsid mass, charge, homogeneity, and transgene packaging characteristics.
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Affiliation(s)
- Mario Mietzsch
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Weijing Liu
- Thermo Fisher Scientific, 355 River Oaks Parkway, San Jose, CA 95134, USA
| | - Ke Ma
- Thermo Fisher Scientific, 490 Lakeside Dr., Sunnyvale, CA 94085, USA
| | - Antonette Bennett
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Austin R. Nelson
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Keely Gliwa
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Paul Chipman
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Xiaofeng Fu
- Biological Science Imaging Resource, Department of Biological Sciences, Florida State University, Tallahassee, FL, USA
| | - Shane Bechler
- Thermo Fisher Scientific, 490 Lakeside Dr., Sunnyvale, CA 94085, USA
| | - Robert McKenna
- Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Rosa Viner
- Thermo Fisher Scientific, 355 River Oaks Parkway, San Jose, CA 95134, USA
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10
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Angsutararux P, Dutta AK, Marras M, Abella C, Mellor RL, Shi J, Nerbonne JM, Silva JR. Differential regulation of cardiac sodium channels by intracellular fibroblast growth factors. J Gen Physiol 2023; 155:e202213300. [PMID: 36944081 PMCID: PMC10038838 DOI: 10.1085/jgp.202213300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/17/2023] [Accepted: 02/09/2023] [Indexed: 03/23/2023] Open
Abstract
Voltage-gated sodium (NaV) channels are responsible for the initiation and propagation of action potentials. In the heart, the predominant NaV1.5 α subunit is composed of four homologous repeats (I-IV) and forms a macromolecular complex with multiple accessory proteins, including intracellular fibroblast growth factors (iFGF). In spite of high homology, each of the iFGFs, iFGF11-iFGF14, as well as the individual iFGF splice variants, differentially regulates NaV channel gating, and the mechanisms underlying these differential effects remain elusive. Much of the work exploring iFGF regulation of NaV1.5 has been performed in mouse and rat ventricular myocytes in which iFGF13VY is the predominant iFGF expressed, whereas investigation into NaV1.5 regulation by the human heart-dominant iFGF12B is lacking. In this study, we used a mouse model with cardiac-specific Fgf13 deletion to study the consequences of iFGF13VY and iFGF12B expression. We observed distinct effects on the voltage-dependences of activation and inactivation of the sodium currents (INa), as well as on the kinetics of peak INa decay. Results in native myocytes were recapitulated with human NaV1.5 heterologously expressed in Xenopus oocytes, and additional experiments using voltage-clamp fluorometry (VCF) revealed iFGF-specific effects on the activation of the NaV1.5 voltage sensor domain in repeat IV (VSD-IV). iFGF chimeras further unveiled roles for all three iFGF domains (i.e., the N-terminus, core, and C-terminus) on the regulation of VSD-IV, and a slower time domain of inactivation. We present here a novel mechanism of iFGF regulation that is specific to individual iFGF isoforms and that leads to distinct functional effects on NaV channel/current kinetics.
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Affiliation(s)
- Paweorn Angsutararux
- Department of Biomedical Engineering, McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Amal K. Dutta
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO, USA
| | - Martina Marras
- Department of Biomedical Engineering, McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Carlota Abella
- Department of Biomedical Engineering, McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Rebecca L. Mellor
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO, USA
| | - Jingyi Shi
- Department of Biomedical Engineering, McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
| | - Jeanne M. Nerbonne
- Department of Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, MO, USA
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Jonathan R. Silva
- Department of Biomedical Engineering, McKelvey School of Engineering, Washington University in St. Louis, St. Louis, MO, USA
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11
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Peterson CD, Waataja JJ, Kitto KF, Erb SJ, Verma H, Schuster DJ, Churchill CC, Riedl MS, Belur LR, Wolf DA, McIvor RS, Vulchanova L, Wilcox GL, Fairbanks CA. Long-term reversal of chronic pain behavior in rodents through elevation of spinal agmatine. Mol Ther 2023; 31:1123-1135. [PMID: 36710491 PMCID: PMC10124077 DOI: 10.1016/j.ymthe.2023.01.022] [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: 07/11/2022] [Revised: 12/08/2022] [Accepted: 01/23/2023] [Indexed: 01/31/2023] Open
Abstract
Chronic pain remains a significant burden worldwide, and treatments are often limited by safety or efficacy. The decarboxylated form of L-arginine, agmatine, antagonizes N-methyl-d-aspartate receptors, inhibits nitric oxide synthase, and reverses behavioral neuroplasticity. We hypothesized that expressing the proposed synthetic enzyme for agmatine in the sensory pathway could reduce chronic pain without motor deficits. Intrathecal delivery of an adeno-associated viral (AAV) vector carrying the gene for arginine decarboxylase (ADC) prevented the development of chronic neuropathic pain as induced by spared nerve injury in mice and rats and persistently reversed established hypersensitivity 266 days post-injury. Spinal long-term potentiation was inhibited by both exogenous agmatine and AAV-human ADC (hADC) vector pre-treatment but was enhanced in rats treated with anti-agmatine immunoneutralizing antibodies. These data suggest that endogenous agmatine modulates the neuroplasticity associated with chronic pain. Development of approaches to access this inhibitory control of neuroplasticity associated with chronic pain may yield important non-opioid pain-relieving options.
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Affiliation(s)
- Cristina D Peterson
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA; Department of Neuroscience, University of Minnesota, Minneapolis, College of Pharmacy, 9-177 Weaver Densford Hall, 308 Harvard Street S.E., Minneapolis, MN 55455, USA; Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA
| | - Jonathan J Waataja
- Department of Neuroscience, University of Minnesota, Minneapolis, College of Pharmacy, 9-177 Weaver Densford Hall, 308 Harvard Street S.E., Minneapolis, MN 55455, USA
| | - Kelley F Kitto
- Department of Neuroscience, University of Minnesota, Minneapolis, College of Pharmacy, 9-177 Weaver Densford Hall, 308 Harvard Street S.E., Minneapolis, MN 55455, USA
| | - Samuel J Erb
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA
| | - Harsha Verma
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA
| | - Daniel J Schuster
- Department of Neuroscience, University of Minnesota, Minneapolis, College of Pharmacy, 9-177 Weaver Densford Hall, 308 Harvard Street S.E., Minneapolis, MN 55455, USA
| | - Caroline C Churchill
- Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA
| | - Maureen S Riedl
- Department of Neuroscience, University of Minnesota, Minneapolis, College of Pharmacy, 9-177 Weaver Densford Hall, 308 Harvard Street S.E., Minneapolis, MN 55455, USA
| | - Lalitha R Belur
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA
| | - Daniel A Wolf
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA
| | - R Scott McIvor
- Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA
| | - Lucy Vulchanova
- Department of Neuroscience, University of Minnesota, Minneapolis, College of Pharmacy, 9-177 Weaver Densford Hall, 308 Harvard Street S.E., Minneapolis, MN 55455, USA
| | - George L Wilcox
- Department of Neuroscience, University of Minnesota, Minneapolis, College of Pharmacy, 9-177 Weaver Densford Hall, 308 Harvard Street S.E., Minneapolis, MN 55455, USA; Department of Pharmacology, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA; Department of Dermatology, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA
| | - Carolyn A Fairbanks
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA; Department of Neuroscience, University of Minnesota, Minneapolis, College of Pharmacy, 9-177 Weaver Densford Hall, 308 Harvard Street S.E., Minneapolis, MN 55455, USA; Department of Experimental and Clinical Pharmacology, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA; Department of Pharmacology, University of Minnesota, Minneapolis, Minneapolis, MN 55455, USA.
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12
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Boye SL, O’Riordan C, Morris J, Lukason M, Compton D, Baek R, Elmore DM, Peterson J, Fajardo D, McCullough KT, Scaria A, McVie-Wylie A, Boye SE. Preclinical studies in support of phase I/II clinical trials to treat GUCY2D-associated Leber congenital amaurosis. Mol Ther Methods Clin Dev 2023; 28:129-145. [PMID: 36654798 PMCID: PMC9830033 DOI: 10.1016/j.omtm.2022.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022]
Abstract
Mutations in GUCY2D are associated with severe early-onset retinal dystrophy, Leber congenital amaurosis type 1 (LCA1), a leading cause of blindness in children. Despite a high degree of visual disturbance stemming from photoreceptor dysfunction, patients with LCA1 largely retain normal photoreceptor structure, suggesting that they are good candidates for gene replacement therapy. The purpose of this study was to conduct the preclinical and IND-enabling experiments required to support clinical application of AAV5-hGRK1-GUCY2D in patients harboring biallelic recessive mutations in GUCY2D. Preclinical studies were conducted in mice to evaluate the effect of vector manufacturing platforms and transgene species on the therapeutic response. Dose-ranging studies were conducted in cynomolgus monkeys to establish the minimum dose required for efficient photoreceptor transduction. Good laboratory practice (GLP) studies evaluated systemic biodistribution in rats and toxicology in non-human primates (NHPs). These results expanded our knowledge of dose response for an AAV5-vectored transgene under control of the human rhodopsin kinase (hGRK1) promoter in NHPs with respect to photoreceptor transduction and safety and, in combination with the rat biodistribution and mouse efficacy studies, informed the design of a first-in-human clinical study in patients with LCA1.
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Affiliation(s)
- Sanford L. Boye
- Powell Gene Therapy Center, Department of Pediatrics, University of Florida, Gainesville, FL 32610, USA
| | | | | | | | | | | | | | | | | | | | | | | | - Shannon E. Boye
- Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, PO Box 100296, Gainesville, FL 32610, USA
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13
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Issa SS, Shaimardanova AA, Solovyeva VV, Rizvanov AA. Various AAV Serotypes and Their Applications in Gene Therapy: An Overview. Cells 2023; 12:cells12050785. [PMID: 36899921 PMCID: PMC10000783 DOI: 10.3390/cells12050785] [Citation(s) in RCA: 41] [Impact Index Per Article: 41.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 02/22/2023] [Accepted: 02/26/2023] [Indexed: 03/06/2023] Open
Abstract
Despite scientific discoveries in the field of gene and cell therapy, some diseases still have no effective treatment. Advances in genetic engineering methods have enabled the development of effective gene therapy methods for various diseases based on adeno-associated viruses (AAVs). Today, many AAV-based gene therapy medications are being investigated in preclinical and clinical trials, and new ones are appearing on the market. In this article, we present a review of AAV discovery, properties, different serotypes, and tropism, and a following detailed explanation of their uses in gene therapy for disease of different organs and systems.
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Affiliation(s)
- Shaza S. Issa
- Department of Genetics and Biotechnology, St. Petersburg State University, 199034 St. Petersburg, Russia
| | - Alisa A. Shaimardanova
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia
| | - Valeriya V. Solovyeva
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia
| | - Albert A. Rizvanov
- Institute of Fundamental Medicine and Biology, Kazan Federal University, 420008 Kazan, Russia
- Correspondence: ; Tel.: +7-(905)-3167599
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14
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Lavi A, Sehgal M, de Sousa AF, Ter-Mkrtchyan D, Sisan F, Luchetti A, Okabe A, Bear C, Silva AJ. Local memory allocation recruits memory ensembles across brain regions. Neuron 2023; 111:470-480.e5. [PMID: 36563678 PMCID: PMC10548338 DOI: 10.1016/j.neuron.2022.11.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 09/29/2022] [Accepted: 11/28/2022] [Indexed: 12/24/2022]
Abstract
Memories are thought to be stored in ensembles of neurons across multiple brain regions. However, whether and how these ensembles are coordinated at the time of learning remains largely unknown. Here, we combined CREB-mediated memory allocation with transsynaptic retrograde tracing to demonstrate that the allocation of aversive memories to a group of neurons in one brain region directly affects the allocation of interconnected neurons in upstream brain regions in a behavioral- and brain region-specific manner in mice. Our analysis suggests that this cross-regional recruitment of presynaptic neurons is initiated by downstream memory neurons through a retrograde mechanism. Together with statistical modeling, our results indicate that in addition to the anterograde flow of information between brain regions, the establishment of interconnected, brain-wide memory traces relies on a retrograde mechanism that coordinates memory ensembles at the time of learning.
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Affiliation(s)
- Ayal Lavi
- Departments of Neurobiology, Psychology, Psychiatry, Integrative Center for Learning and Memory and Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Megha Sehgal
- Departments of Neurobiology, Psychology, Psychiatry, Integrative Center for Learning and Memory and Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Andre F de Sousa
- Departments of Neurobiology, Psychology, Psychiatry, Integrative Center for Learning and Memory and Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Donara Ter-Mkrtchyan
- Departments of Neurobiology, Psychology, Psychiatry, Integrative Center for Learning and Memory and Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Fardad Sisan
- Departments of Neurobiology, Psychology, Psychiatry, Integrative Center for Learning and Memory and Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Alessandro Luchetti
- Departments of Neurobiology, Psychology, Psychiatry, Integrative Center for Learning and Memory and Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Anna Okabe
- Departments of Neurobiology, Psychology, Psychiatry, Integrative Center for Learning and Memory and Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Cameron Bear
- Departments of Neurobiology, Psychology, Psychiatry, Integrative Center for Learning and Memory and Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA
| | - Alcino J Silva
- Departments of Neurobiology, Psychology, Psychiatry, Integrative Center for Learning and Memory and Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA.
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15
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Ridley RB, Bowman BM, Lee J, Walsh E, Massengill MT, Lewin AS, Ildefonso CJ. Modulation of Retinal Inflammation Delays Degeneration in a Mouse Model of Geographic Atrophy. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.08.527757. [PMID: 36798403 PMCID: PMC9934704 DOI: 10.1101/2023.02.08.527757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
The advanced form of AMD, geographic atrophy, is associated with increased RPE oxidative stress and chronic inflammation. Here we evaluated the effects of delivering an anti-inflammatory viral gene by an AAV-vector in a mouse model of geographic atrophy. We measured changes in retinal function, structure, and morphology over nine months with electroretinography, optical coherence tomography, and fundoscopy, respectively. In addition, we used retinal tissue to quantify changes in markers of inflammation by multiplex ELISA, RT-qPCR, and immunofluorescence staining. Our AAV significantly delayed the loss of retinal function and structure and decreased retinal inflammation compared to the control AAV treatment. Our results suggest that modulating retinal inflammation could significantly slow the progression of geographic atrophy.
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16
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Ahmed CM, Massengill MT, Ildefonso CJ, Jalligampala A, Zhu P, Li H, Patel AP, McCall MA, Lewin AS. Binocular benefit following monocular subretinal AAV injection in a mouse model of autosomal dominant retinitis pigmentosa (adRP). Vision Res 2023; 206:108189. [PMID: 36773475 DOI: 10.1016/j.visres.2023.108189] [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: 12/09/2022] [Revised: 01/05/2023] [Accepted: 01/05/2023] [Indexed: 02/11/2023]
Abstract
Autosomal dominant retinitis pigmentosa (adRP) is frequently caused by mutations in RHO, the gene for rhodopsin. In previous experiments in dogs with the T4R mutation in RHO, an AAV2/5 vector expressing an shRNA directed to human and dog RHO mRNA and an shRNA-resistant human RHO cDNA (AAV-RHO820-shRNA820) prevented retinal degeneration for more than eight months following injection. It is crucial, however, to determine if this RNA replacement vector acts in a mutation-independent and species-independent manner. We, therefore, injected mice transgenic for human P23H RHO with this vector unilaterally at postnatal day 30. We monitored their retinal structure by using spectral-domain optical coherence tomography (SD-OCT) and retinal function using electroretinography (ERG) for nine months. We compared these to P23H RHO transgenic mice injected unilaterally with a control vector. Though retinas continued to thin over time, compared to control injected eyes, treatment with AAV-RHO820-shRNA820 slowed the loss of photoreceptor cells and the decrease in ERG amplitudes during the nine-month study period. Unexpectedly, we also observed the preservation of retinal structure and function in the untreated contralateral eyes of AAV-RHO820-shRNA820 treated mice. PCR analysis and western blots showed that a low amount of vector from injected eyes was present in uninjected eyes. In addition, protective neurotrophic factors bFGF and GDNF were elevated in both eyes of treated mice. Our finding suggests that using this or similar RNA replacement vectors in human gene therapy may provide clinical benefit to both eyes of patients with adRP.
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Affiliation(s)
- Chulbul M Ahmed
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, USA
| | - Michael T Massengill
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, USA
| | | | - Archana Jalligampala
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY, USA
| | - Ping Zhu
- Department of Ophthalmology, University of Florida, Gainesville, FL, USA
| | - Hong Li
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, USA
| | - Anil P Patel
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, USA
| | - Maureen A McCall
- Department of Ophthalmology and Visual Sciences, University of Louisville, Louisville, KY, USA
| | - Alfred S Lewin
- Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL, USA.
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17
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Kearney AM. Chromatographic Purification of Viral Vectors for Gene Therapy Applications. Methods Mol Biol 2023; 2699:51-60. [PMID: 37646993 DOI: 10.1007/978-1-0716-3362-5_4] [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] [Indexed: 09/01/2023]
Abstract
Chromatography has been a mainstay in the downstream processing and purification of biopharmaceutical medicines. Until now, this has largely involved the purification of protein products such as recombinant enzymes and monoclonal antibodies using large-scale column chromatography methods. The development of advanced therapeutic medicinal products (ATMP) is heralding in a new era of therapeutics for a range of indications. These new therapeutics use diverse substances ranging from live stem cell preparations to fragments of nucleic acid enclosed in a viral delivery system. With these new technologies come new challenges in their purification. In this chapter, the challenges faced in producing and purifying viral vectors capable of delivering life-altering gene therapy to the patient will be discussed. Current methods of chromatography capable of adaptation to meet these new challenges and advancements that may be needed to increase the purification capabilities for these new products will also be discussed.
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18
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Calabro KR, Boye SL, Boye SE. Optimization of Capillary-Based Western Blotting for MYO7A. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2023; 1415:125-130. [PMID: 37440024 DOI: 10.1007/978-3-031-27681-1_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/14/2023]
Abstract
Myosin VIIA (MYO7A)-associated Usher syndrome type 1B (USH1B) is a severe disorder that impacts the auditory, vestibular, and visual systems of affected patients. Due to the large size (~7.5 kb) of the MYO7A coding sequence, we have designed a dual adeno-associated virus (AAV) vector-based approach for the treatment of USH1B-related vision loss. Due to the added complexity of dual-AAV gene therapy, careful attention must be paid to the protein products expressed following vector recombination. In order to improve the sensitivity and quantifiability of our immunoassays, we adapted our traditional western blot protocol for use with the Jess™ Simple Western System. Following several rounds of testing, we optimized our protocol for the detection of MYO7A in two of our most frequently used sample types, mouse eyes, and infected HEK293 cell lysates.
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Affiliation(s)
- Kaitlyn R Calabro
- Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Sanford L Boye
- Department of Pediatrics, University of Florida, Gainesville, FL, USA
| | - Shannon E Boye
- Department of Pediatrics, University of Florida, Gainesville, FL, USA.
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19
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Reimer L, Gram H, Jensen NM, Betzer C, Yang L, Jin L, Shi M, Boudeffa D, Fusco G, De Simone A, Kirik D, Lashuel HA, Zhang J, Jensen PH. Protein kinase R dependent phosphorylation of α-synuclein regulates its membrane binding and aggregation. PNAS NEXUS 2022; 1:pgac259. [PMID: 36712380 PMCID: PMC9802061 DOI: 10.1093/pnasnexus/pgac259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Accepted: 11/07/2022] [Indexed: 11/18/2022]
Abstract
Aggregated α-synuclein (α-syn) accumulates in the neuronal Lewy body (LB) inclusions in Parkinson's disease (PD) and LB dementia. Yet, under nonpathological conditions, monomeric α-syn is hypothesized to exist in an equilibrium between disordered cytosolic- and partially α-helical lipid-bound states: a feature presumably important in synaptic vesicle release machinery. The exact underlying role of α-syn in these processes, and the mechanisms regulating membrane-binding of α-syn remains poorly understood. Herein we demonstrate that Protein kinase R (PKR) can phosphorylate α-syn at several Ser/Thr residues located in the membrane-binding region that is essential for α-syn's vesicle-interactions. α-Syn phosphorylated by PKR or α-syn isolated from PKR overexpressing cells, exhibit decreased binding to lipid membranes. Phosphorylation of Thr64 and Thr72 appears as the major contributor to this effect, as the phosphomimetic Thr64Glu/Thr72Glu-α-syn mutant displays reduced overall attachment to brain vesicles due to a decrease in vesicle-affinity of the last two thirds of α-syn's membrane binding region. This allows enhancement of the "double-anchor" vesicle-binding mechanism that tethers two vesicles and thus promote the clustering of presynaptic vesicles in vitro. Furthermore, phosphomimetic Thr64Glu/Thr72Glu-α-syn inhibits α-syn oligomerization and completely abolishes nucleation, elongation, and seeding of α-syn fibrillation in vitro and in cells, and prevents trans-synaptic spreading of aggregated α-syn pathology in organotypic hippocampal slice cultures. Overall, our findings demonstrate that normal and abnormal functions of α-syn, like membrane-binding, synaptic vesicle clustering and aggregation can be regulated by phosphorylation, e.g., via PKR. Mechanisms that could potentially be modulated for the benefit of patients suffering from α-syn aggregate-related diseases.
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Affiliation(s)
| | - Hjalte Gram
- Danish Research Institute of Translational Neuroscience - DANDRITE, Aarhus University, 8000 Aarhus C, Denmark,Department of Biomedicine, Aarhus University, 8000 Aarhus C, Denmark
| | - Nanna Møller Jensen
- Danish Research Institute of Translational Neuroscience - DANDRITE, Aarhus University, 8000 Aarhus C, Denmark,Department of Biomedicine, Aarhus University, 8000 Aarhus C, Denmark
| | - Cristine Betzer
- Danish Research Institute of Translational Neuroscience - DANDRITE, Aarhus University, 8000 Aarhus C, Denmark,Department of Biomedicine, Aarhus University, 8000 Aarhus C, Denmark
| | - Li Yang
- Department of Pathology, University of Washington School of Medicine, Seattle WA 98195, USA
| | - Lorrain Jin
- Department of Pathology, University of Washington School of Medicine, Seattle WA 98195, USA
| | - Min Shi
- Department of Pathology, University of Washington School of Medicine, Seattle WA 98195, USA
| | - Driss Boudeffa
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences Brain Mind Institute, Station 19, 1015 Lausanne, Switzerland
| | - Giuliana Fusco
- Centre for Misfolding Diseases,Department of Chemistry, University of Cambridge, CB2 1EW, UK
| | | | - Deniz Kirik
- Brain Repair and Imaging in Neural Systems, Department of Experimental Medical Science, Lund University, 22184 Lund, Sweden
| | - Hilal A Lashuel
- Laboratory of Molecular and Chemical Biology of Neurodegeneration, School of Life Sciences Brain Mind Institute, Station 19, 1015 Lausanne, Switzerland
| | - Jing Zhang
- Department of Pathology, University of Washington School of Medicine, Seattle WA 98195, USA,Department of Pathology, Zhejiang University School of Medicine and the First Affiliated Hospital, 310003 Hangzhou, China
| | - Poul Henning Jensen
- Danish Research Institute of Translational Neuroscience - DANDRITE, Aarhus University, 8000 Aarhus C, Denmark,Department of Biomedicine, Aarhus University, 8000 Aarhus C, Denmark
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20
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Nam MH, Nahomi RB, Pantcheva MB, Dhillon A, Chiodo VA, Smith WC, Nagaraj RH. AAV2-Mediated Expression of HspB1 in RGCs Prevents Somal Damage and Axonal Transport Deficits in a Mouse Model of Ocular Hypertension. Transl Vis Sci Technol 2022; 11:8. [DOI: 10.1167/tvst.11.11.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Mi-Hyun Nam
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
| | - Rooban B. Nahomi
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
| | - Mina B. Pantcheva
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
| | - Armaan Dhillon
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
| | - Vince A. Chiodo
- Department of Ophthalmology, University of Florida, Gainesville, FL, USA
| | - W. Clay Smith
- Department of Ophthalmology, University of Florida, Gainesville, FL, USA
| | - Ram H. Nagaraj
- Sue Anschutz-Rodgers Eye Center and Department of Ophthalmology, School of Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado, Anschutz Medical Campus, Aurora, CO, USA
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21
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Yang J, Serrano P, Yin X, Sun X, Lin Y, Chen SX. Functionally distinct NPAS4-expressing somatostatin interneuron ensembles critical for motor skill learning. Neuron 2022; 110:3339-3355.e8. [PMID: 36099920 DOI: 10.1016/j.neuron.2022.08.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 07/01/2022] [Accepted: 08/15/2022] [Indexed: 10/14/2022]
Abstract
During motor learning, dendritic spines on pyramidal neurons (PNs) in the primary motor cortex (M1) undergo reorganization. Intriguingly, the inhibition from local somatostatin-expressing inhibitory neurons (SST-INs) plays an important role in regulating the PN plasticity and thus new motor skill acquisition. However, the molecular mechanisms underlying this process remain unclear. Here, we identified that the early-response transcription factor, NPAS4, is selectively expressed in SST-INs during motor learning. By utilizing in vivo two-photon imaging in mice, we found that cell-type-specific deletion of Npas4 in M1 disrupted learning-induced spine reorganization among PNs and impaired motor learning. In addition, NPAS4-expressing SST-INs exhibited lower neuronal activity during task-related movements, and chemogenetically increasing the activity of NPAS4-expressing ensembles was sufficient to mimic the effects of Npas4 deletion. Together, our results reveal an instructive role of NPAS4-expressing SST-INs in modulating the inhibition to downstream task-related PNs to allow proper spine reorganization that is critical for motor learning.
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Affiliation(s)
- Jungwoo Yang
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Pablo Serrano
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Xuming Yin
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Xiaochen Sun
- Department of Psychiatry and Behavioral Sciences, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Yingxi Lin
- Department of Psychiatry and Behavioral Sciences, SUNY Upstate Medical University, Syracuse, NY 13210, USA
| | - Simon X Chen
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada; Brain and Mind Research Institute, University of Ottawa, Ottawa, ON K1H 8M5, Canada; Center for Neural Dynamics, University of Ottawa, Ottawa, ON K1H 8M5, Canada.
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22
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Roger AL, Sethi R, Huston ML, Scarrow E, Bao-Dai J, Lai E, Biswas DD, Haddad LE, Strickland LM, Kishnani PS, ElMallah MK. What's new and what's next for gene therapy in Pompe disease? Expert Opin Biol Ther 2022; 22:1117-1135. [PMID: 35428407 PMCID: PMC10084869 DOI: 10.1080/14712598.2022.2067476] [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: 01/06/2022] [Accepted: 04/14/2022] [Indexed: 11/04/2022]
Abstract
INTRODUCTION Pompe disease is an autosomal recessive disorder caused by a deficiency of acid-α-glucosidase (GAA), an enzyme responsible for hydrolyzing lysosomal glycogen. A lack of GAA leads to accumulation of glycogen in the lysosomes of cardiac, skeletal, and smooth muscle cells, as well as in the central and peripheral nervous system. Enzyme replacement therapy has been the standard of care for 15 years and slows disease progression, particularly in the heart, and improves survival. However, there are limitations of ERT success, which gene therapy can overcome. AREAS COVERED Gene therapy offers several advantages including prolonged and consistent GAA expression and correction of skeletal muscle as well as the critical CNS pathology. We provide a systematic review of the preclinical and clinical outcomes of adeno-associated viral mediated gene therapy and alternative gene therapy strategies, highlighting what has been successful. EXPERT OPINION Although the preclinical and clinical studies so far have been promising, barriers exist that need to be addressed in gene therapy for Pompe disease. New strategies including novel capsids for better targeting, optimized DNA vectors, and adjuctive therapies will allow for a lower dose, and ameliorate the immune response.
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Affiliation(s)
- Angela L. Roger
- Division of Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina, 27710, USA
| | - Ronit Sethi
- Division of Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina, 27710, USA
| | - Meredith L. Huston
- Division of Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina, 27710, USA
| | - Evelyn Scarrow
- Division of Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina, 27710, USA
| | - Joy Bao-Dai
- Division of Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina, 27710, USA
| | - Elias Lai
- Division of Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina, 27710, USA
| | - Debolina D. Biswas
- Division of Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina, 27710, USA
| | - Léa El Haddad
- Division of Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina, 27710, USA
| | - Laura M. Strickland
- Division of Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina, 27710, USA
| | - Priya S. Kishnani
- Division of Medical Genetics, Department of Pediatrics, Duke University, Durham, North Carolina USA
| | - Mai K. ElMallah
- Division of Pulmonary Medicine, Department of Pediatrics, Duke University Medical Center Box 2644, Durham, North Carolina, 27710, USA
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23
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Nelson TS, Simpson C, Dyka F, Dinculescu A, Smith WC. A Modified Arrestin1 Increases Lactate Production in the Retina and Slows Retinal Degeneration. Hum Gene Ther 2022; 33:695-707. [PMID: 35081746 PMCID: PMC9347377 DOI: 10.1089/hum.2021.272] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Glucose metabolism in the retina is carefully orchestrated, with glucose being delivered to photoreceptors from the choroidal circulation through the retinal pigmented epithelium (RPE). In photoreceptors, glucose is processed principally by aerobic glycolysis, from which the lactate byproduct is provided to the RPE and Müller glia for their energetic needs. In this study, we utilize a modified arrestin1 protein to enhance the glycolytic output of lactate from rod photoreceptors through disinhibition of enolase1 activity with the goal being to use this increased lactate production as a gene-agnostic approach to slowing retinal degeneration. Mouse arrestin1 with E362G/D363G amino acid substitutions (referred to as "ArrGG") was packaged into AAV and tested for safety and for efficacy in increasing retinal lactate production. Overexpression of ArrGG in C57BL/6J mice did not result in any detectable changes in either electroretinogram (ERG) function or photoreceptor survival as measured by outer nuclear layer (ONL) thickness. However, mouse retinas expressing ArrGG showed a ∼25% increase in the rate of lactate secretion. Therefore, AAV-ArrGG was delivered intravitreally to heterozygous P23H rhodopsin knockin mice (RhoP23H/+) to determine if enhancing glycolysis in photoreceptors can slow retinal degeneration in this animal model of retinitis pigmentosa. We found that the expression of ArrGG in these mice slowed the decline of both scotopic and photopic ERG function. Correspondingly, there was significant preservation of ONL thickness in RhoP23H/+ mice treated with ArrGG compared with controls. In conclusion, our studies show that expressing ArrGG in C57BL/6J mouse retina results in an increase in lactate production, consistent with an upregulation of glycolysis. In the P23H rhodopsin model of retinitis pigmentosa, the expression of ArrGG led to significant preservation of photoreceptor function and slowing of retinal degeneration. These findings suggest that enhancing glycolysis by targeting increased enolase1 activity with a modified arrestin1 in photoreceptors may offer a therapeutic approach to slowing retinal degeneration.
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Affiliation(s)
- Tiffany S Nelson
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Chiab Simpson
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Frank Dyka
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Astra Dinculescu
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - W Clay Smith
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
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24
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Belova L, Kochergin‐Nikitsky K, Erofeeva A, Lavrov A, Smirnikhina S. Approaches to purification and concentration of rAAV vectors for gene therapy. Bioessays 2022; 44:e2200019. [DOI: 10.1002/bies.202200019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 11/11/2022]
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25
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Habbas K, Cakil O, Zámbó B, Tabet R, Riet F, Dembele D, Mandel JL, Hocquemiller M, Laufer R, Piguet F, Moine H. AAV-delivered diacylglycerol kinase DGKk achieves long-term rescue of fragile X syndrome mouse model. EMBO Mol Med 2022; 14:e14649. [PMID: 35373916 PMCID: PMC9081908 DOI: 10.15252/emmm.202114649] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 11/09/2022] Open
Abstract
Fragile X syndrome (FXS) is the most frequent form of familial intellectual disability. FXS results from the lack of the RNA-binding protein FMRP and is associated with the deregulation of signaling pathways downstream of mGluRI receptors and upstream of mRNA translation. We previously found that diacylglycerol kinase kappa (DGKk), a main mRNA target of FMRP in cortical neurons and a master regulator of lipid signaling, is downregulated in the absence of FMRP in the brain of Fmr1-KO mouse model. Here we show that adeno-associated viral vector delivery of a modified and FMRP-independent form of DGKk corrects abnormal cerebral diacylglycerol/phosphatidic acid homeostasis and FXS-relevant behavioral phenotypes in the Fmr1-KO mouse. Our data suggest that DGKk is an important factor in FXS pathogenesis and provide preclinical proof of concept that its replacement could be a viable therapeutic strategy in FXS.
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Affiliation(s)
- Karima Habbas
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Département de Médecine Translationelle et Neurogénétique, Centre National de la Recherche Scientifique (CNRS UMR7104), Institut National de la Santé et de la Recherche Médicale (INSERM U1258), Université de Strasbourg, Illkirch, France
| | - Oktay Cakil
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Département de Médecine Translationelle et Neurogénétique, Centre National de la Recherche Scientifique (CNRS UMR7104), Institut National de la Santé et de la Recherche Médicale (INSERM U1258), Université de Strasbourg, Illkirch, France
| | - Boglárka Zámbó
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Département de Médecine Translationelle et Neurogénétique, Centre National de la Recherche Scientifique (CNRS UMR7104), Institut National de la Santé et de la Recherche Médicale (INSERM U1258), Université de Strasbourg, Illkirch, France
| | - Ricardos Tabet
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Département de Médecine Translationelle et Neurogénétique, Centre National de la Recherche Scientifique (CNRS UMR7104), Institut National de la Santé et de la Recherche Médicale (INSERM U1258), Université de Strasbourg, Illkirch, France
| | - Fabrice Riet
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), PHENOMIN-ICS, Centre National de la Recherche Scientifique (CNRS UMR7104), Institut National de la Santé et de la Recherche Médicale (INSERM U1258), Université de Strasbourg, Illkirch, France
| | - Doulaye Dembele
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Département de Médecine Translationelle et Neurogénétique, Centre National de la Recherche Scientifique (CNRS UMR7104), Institut National de la Santé et de la Recherche Médicale (INSERM U1258), Université de Strasbourg, Illkirch, France
| | - Jean-Louis Mandel
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Département de Médecine Translationelle et Neurogénétique, Centre National de la Recherche Scientifique (CNRS UMR7104), Institut National de la Santé et de la Recherche Médicale (INSERM U1258), Université de Strasbourg, Illkirch, France
| | | | | | - Françoise Piguet
- NeuroGenCell, INSERM U1127, Paris Brain Institute (ICM), Sorbonne University, CNRS, AP-HP, University Hospital Pitié-Salpêtrière, Paris, France
| | - Hervé Moine
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Département de Médecine Translationelle et Neurogénétique, Centre National de la Recherche Scientifique (CNRS UMR7104), Institut National de la Santé et de la Recherche Médicale (INSERM U1258), Université de Strasbourg, Illkirch, France
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26
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Deng WT, Ma X, Sechrest E, Fajardo D, Zhu P, Dyka FM, Wang Y, Lobanova E, Boye S, Baehr W. Gene Therapy in Opn1mw-/-/Opn1sw-/- Mice and Implications for Blue Cone Monochromacy Patients with Deletion Mutations. Hum Gene Ther 2022; 33:708-718. [PMID: 35272502 PMCID: PMC9347391 DOI: 10.1089/hum.2021.298] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Blue cone monochromacy (BCM) is a congenital vision disorder affecting both middle- wavelength (M) and long-wavelength (L) cone photoreceptors of the human retina. BCM results from abolished expression of green and red light-sensitive visual pigments expressed in M- and L-cones, respectively. Previously, we showed that gene augmentation therapy to deliver either human L- or M-opsin rescues dorsal M-opsin dominant cone photoreceptors structurally and functionally in treated M-opsin knockout (Opn1mw-/-) mice. Although Opn1mw-/- mice represent a disease model for BCM patients with deletion mutations, at the cellular level dorsal cones of Opn1mw-/- mice still express low levels of S-opsin which are different from L- and M-cones of BCM patients carrying a congenital opsin deletion. To determine whether BCM cones lacking complete opsin expression from birth would benefit from AAV-mediated gene therapy, we evaluated the outcome of gene therapy, and determined the therapeutic window and longevity of rescue in a mouse model lacking both M- and S- opsin (Opn1mw-/-/Opn1sw-/-). Our data show that cones of Opn1mw-/-/Opn1sw-/- mice are viable at younger ages but undergo rapid degeneration. AAV-mediated expression of human L-opsin promoted cone outer segment regeneration and rescued cone-mediated function when mice were injected subretinally at 2 months of age or younger. Cone-mediated function and visually guided behavior were maintained for at least 8 months post-treatment. However, when mice were treated at 5 and 7 months of age, the chance and effectiveness of rescue was significantly reduced, though cones were still present in the retina. Crossing Opn1mw-/-/Opn1sw-/- mice with proteasomal activity reporter mice (UbG76V-GFP) did not reveal GFP accumulation in Opn1mw-/-/Opn1sw-/- cones eliminating impaired degradation of ubiquitinated proteins as stress factor contributing to cone loss. Our results demonstrate that AAV-mediated gene augmentation therapy can rescue cone structure and function in a mouse model with a congenital opsin deletion, but also emphasize the importance that early intervention is crucial for successful therapy. .
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Affiliation(s)
- Wen-Tao Deng
- West Virginia University, 5631, Ophthalmology, 108 Medical Rd, Morgantown, West Virginia, United States, 26506-6201.,West Virginia University, 5631, Biochemistry, Morgantown, United States, 26506-6201;
| | - Xiajie Ma
- University of Florida, 3463, Gainesville, Florida, United States;
| | - Emily Sechrest
- West Virginia University, 5631, Morgantown, West Virginia, United States;
| | - Diego Fajardo
- University of Florida , Ophthalmology, Gainesville, Florida, United States;
| | - Ping Zhu
- University of Florida, Ophthalmology, ARB RG-240, 1600 SW Archer road, Gainesville, Florida, United States, 32610.,University of Florida, Ophthalmology Department, 1600 SW Archer Rd, Gainesville, Florida, United States, 32610;
| | - Frank M Dyka
- University of Florida, Ophthalmology, ARB R1-236, 1600 SW Archer Road, Gainesville, Florida, United States, 32610;
| | - Yixiao Wang
- University of Florida, 3463, Ophthalmology, Gainesville, Florida, United States;
| | - Ekaterina Lobanova
- University of Florida, 3463, Ophthalmology, Gainesville, Florida, United States;
| | - Shannon Boye
- University of Florida , PO Box 100284, Gainesville, Florida, United States, 32606;
| | - Wolfgang Baehr
- University of Utah Health Science Center, Ophthalmology, 65 Mario Capecchi Dr., Moran Eye Center, Salt Lake City, Utah, United States, 84132;
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27
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Arotcarena ML, Dovero S, Biendon N, Dutheil N, Planche V, Bezard E, Dehay B. Pilot Study Assessing the Impact of Intrathecal Administration of Variants AAV-PHP.B and AAV-PHP.eB on Brain Transduction in Adult Rhesus Macaques. Front Bioeng Biotechnol 2021; 9:762209. [PMID: 34869273 PMCID: PMC8634843 DOI: 10.3389/fbioe.2021.762209] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2021] [Accepted: 10/26/2021] [Indexed: 01/15/2023] Open
Abstract
Adeno-associated virus (AAV) vectors are increasingly used as an effective and safe approach to deliver genetic material to the central nervous system (CNS). The AAV9-derived variants, AAV-PHP. B and AAV-PHP.eB, reportedly broadly transduce cells throughout the CNS compared to the original serotype 9, AAV9. As non-human primate data are scarce, we here evaluated the CNS transduction efficiencies after lumbar intrathecal bolus delivery of identical doses of either AAV-PHP. B:CAG-EGFP or AAV-PHP. eB:CAG-EGFP in rhesus macaque monkeys. AAV-PHP.eB achieved a more efficient and widespread CNS transduction compared to AAV-PHP.B. We report a strong neuronal and oligodendroglial tropism for both variants in the putamen and in the hippocampus. This proof-of-concept experiment highlights the potential value of intrathecal infusions of AAV-PHP.eB to distribute genetic material in the CNS with cell-type specificity and introduces a new opportunity to model brain diseases in rhesus macaque monkeys and further develop gene therapies targeting the CNS in humans.
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Affiliation(s)
| | - Sandra Dovero
- CNRS, IMN, UMR 5293, Univ. Bordeaux, Bordeaux, France
| | | | | | - Vincent Planche
- CNRS, IMN, UMR 5293, Univ. Bordeaux, Bordeaux, France.,Centre Memoire de Ressources et de Recherches, Pôle de Neurosciences Cliniques, CHU de Bordeaux, Bordeaux, France
| | - Erwan Bezard
- CNRS, IMN, UMR 5293, Univ. Bordeaux, Bordeaux, France
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28
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Bennett A, Hull J, Jolinon N, Tordo J, Moss K, Binns E, Mietzsch M, Hagemann C, Linden RM, Serio A, Chipman P, Sousa D, Broecker F, Seeberger P, Henckaerts E, McKenna R, Agbandje-McKenna M. Comparative structural, biophysical, and receptor binding study of true type and wild type AAV2. J Struct Biol 2021; 213:107795. [PMID: 34509611 PMCID: PMC9918372 DOI: 10.1016/j.jsb.2021.107795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/27/2021] [Accepted: 09/05/2021] [Indexed: 01/25/2023]
Abstract
Adeno-associated viruses (AAV) are utilized as gene transfer vectors in the treatment of monogenic disorders. A variant, rationally engineered based on natural AAV2 isolates, designated AAV-True Type (AAV-TT), is highly neurotropic compared to wild type AAV2 in vivo, and vectors based on it, are currently being evaluated for central nervous system applications. AAV-TT differs from AAV2 by 14 amino acids, including R585S and R588T, two residues previously shown to be essential for heparan sulfate binding of AAV2. The capsid structures of AAV-TT and AAV2 visualized by cryo-electron microscopy at 3.4 and 3.0 Å resolution, respectively, highlighted structural perturbations at specific amino acid differences. Differential scanning fluorimetry (DSF) performed at different pH conditions demonstrated that the melting temperature (Tm) of AAV2 was consistently ∼5 °C lower than AAV-TT, but both showed maximal stability at pH 5.5, corresponding to the pH in the late endosome, proposed as required for VP1u externalization to facilitate endosomal escape. Reintroduction of arginines at positions 585 and 588 in AAV-TT caused a reduction in Tm, demonstrating that the lack of basic amino acids at these positions are associated with capsid stability. These results provide structural and thermal annotation of AAV2/AAV-TT residue differences, that account for divergent cell binding, transduction, antigenic reactivity, and transduction of permissive tissues between the two viruses. Specifically, these data indicate that AAV-TT may not utilize a glycan receptor mediated pathway to enter cells and may have lower antigenic properties as compared to AAV2.
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Affiliation(s)
- Antonette Bennett
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Joshua Hull
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Nelly Jolinon
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK
| | | | - Katie Moss
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Enswert Binns
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Mario Mietzsch
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Cathleen Hagemann
- Centre for Craniofacial & Regenerative Biology, King's College London, London SE19RT, UK; The Francis Crick Institute, London NW1 1AT, UK
| | | | - Andrea Serio
- Centre for Craniofacial & Regenerative Biology, King's College London, London SE19RT, UK; The Francis Crick Institute, London NW1 1AT, UK
| | - Paul Chipman
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
| | - Duncan Sousa
- Biological Science Imaging Resource, Department of Biological Sciences, Florida State University, 89 Chieftan Way Rm 119, Tallahassee, FL 32306, USA
| | - Felix Broecker
- Department of Biomolecular Systems, Max-Planck-Institute of Colloids and Interfaces, 14476 Potsdam, Germany
| | - Peter Seeberger
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, 14195 Berlin, Germany
| | - Els Henckaerts
- Department of Infectious Diseases, School of Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK; Laboratory of Viral Cell Biology and Therapeutics, Department of Cellular and Molecular Medicine, Department of Microbiology, Immunology and Transplantation, KU Leuven, 3000 Leuven, Belgium.
| | - Robert McKenna
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA.
| | - Mavis Agbandje-McKenna
- Department of Biochemistry & Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL 32610, USA
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29
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Pflepsen KR, Peterson CD, Kitto KF, Riedl MS, McIvor RS, Wilcox GL, Vulchanova L, Fairbanks CA. Biodistribution of Adeno-Associated Virus Serotype 5 Viral Vectors Following Intrathecal Injection. Mol Pharm 2021; 18:3741-3749. [PMID: 34460254 DOI: 10.1021/acs.molpharmaceut.1c00252] [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: 11/30/2022]
Abstract
The pharmacokinetic profile of AAV particles following intrathecal delivery has not yet been clearly defined. The present study evaluated the distribution profile of adeno-associated virus serotype 5 (AAV5) viral vectors following lumbar intrathecal injection in mice. After a single bolus intrathecal injection, viral DNA concentrations in mouse whole blood, spinal cord, and peripheral tissues were determined using quantitative polymerase chain reaction (qPCR). The kinetics of AAV5 vector in whole blood and the concentration over time in spinal and peripheral tissues were analyzed. Distribution of the AAV5 vector to all levels of the spinal cord, dorsal root ganglia, and into systemic circulation occurred rapidly within 30 min following injection. Vector concentration in whole blood reached a maximum 6 h postinjection with a half-life of approximately 12 h. Area under the curve data revealed the highest concentration of vector distributed to dorsal root ganglia tissue. Immunohistochemical analysis revealed AAV5 particle colocalization with the pia mater at the spinal cord and macrophages in the dorsal root ganglia (DRG) 30 min after injection. These results demonstrate the widespread distribution of AAV5 particles through cerebrospinal fluid and preferential targeting of DRG tissue with possible clearance mechanisms via DRG macrophages.
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Affiliation(s)
- Kelsey R Pflepsen
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Cristina D Peterson
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Kelley F Kitto
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Maureen S Riedl
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - R Scott McIvor
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - George L Wilcox
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States.,Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota 55455, United States.,Department of Dermatology, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Lucy Vulchanova
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Carolyn A Fairbanks
- Department of Pharmaceutics, University of Minnesota, Minneapolis, Minnesota 55455, United States.,Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, United States.,Department of Pharmacology, University of Minnesota, Minneapolis, Minnesota 55455, United States
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30
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Zhu P, Dyka F, Ma X, Yin L, Yu H, Baehr W, Hauswirth WW, Deng WT. Disease mechanisms of X-linked cone dystrophy caused by missense mutations in the red and green cone opsins. FASEB J 2021; 35:e21927. [PMID: 34547123 PMCID: PMC8462070 DOI: 10.1096/fj.202101066r] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/12/2021] [Accepted: 08/31/2021] [Indexed: 11/11/2022]
Abstract
Cone photoreceptors are responsible for the visual acuity and color vision of the human eye. Red/green cone opsin missense mutations N94K, W177R, P307L, R330Q, and G338E have been identified in subjects with congenital blue cone monochromacy or color‐vision deficiency. Studies on disease mechanisms due to these cone opsin mutations have been previously carried out exclusively in vitro, and the reported impairments were not always consistent. Here we expressed these mutants via AAV specifically in vivo in M‐opsin knockout mouse cones to investigate their subcellular localization, the pathogenic effects on cone structure, function, and cone viability. We show that these mutations alter the M‐opsin structure, function, and localization. N94K and W177R mutants appeared to be misfolded since they localized exclusively in cone inner segments and endoplasmic reticulum. In contrast, P307L, R330Q, and G338E mutants were detected predominately in cone outer segments. Expression of R330Q and G338E, but not P307L opsins, also partially restored expression and correct localization of cone PDE6α’ and cone transducin γ and resulted in partial rescue of M‐cone‐mediated light responses. Expression of W177R and P307L mutants significantly reduced cone viability, whereas N94K, R330Q, and G338E were only modestly toxic. We propose that although the underlying biochemical and cellular defects caused by these mutants are distinct, they all seem to exhibit a dominant phenotype, resembling autosomal dominant retinitis pigmentosa associated with the majority of rhodopsin missense mutations. The understanding of the molecular mechanisms associated with these cone opsin mutants is fundamental to developing targeted therapies for cone dystrophy/dysfunction.
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Affiliation(s)
- Ping Zhu
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Frank Dyka
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Xiaojie Ma
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Ling Yin
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Heather Yu
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Wolfgang Baehr
- Department of Ophthalmology, John A. Moran Eye Center, University of Utah Health Science Center, Salt Lake City, Utah, USA.,Department of Neurobiology and Anatomy, University of Utah Health Science Center, Salt Lake City, Utah, USA.,Department of Biology, University of Utah, Salt Lake City, Utah, USA
| | - William W Hauswirth
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Wen-Tao Deng
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
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31
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Guggino WB, Yanda MK, Cebotaru CV, Cebotaru L. Transduction of Surface and Basal Cells in Rhesus Macaque Lung Following Repeat Dosing with AAV1CFTR. Hum Gene Ther 2021; 31:1010-1023. [PMID: 32862701 DOI: 10.1089/hum.2020.207] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
To test the effectiveness of repeat dosing, we sprayed two doses (1013 vg each) of AAV1Δ27-264-CFTR into airways of four rhesus monkeys at 0 and 30 days, followed by a single dose of 1013 vg of AAV1GFP on day 60. Monkeys were sacrificed on day 90. No adverse events occurred, indicating that AAV1 vectors are safe. An elevated anti-AAV1 neutralizing titer was established by the third dose. A positive ELISPOT to the adeno-associated virus (AAV) capsid but not to cystic fibrosis transmembrane conductance regulator (CFTR) occurred after the third dose in three monkeys. AAV1-CFTR and GFP vectors were detectable in all lung sections and in the heart, liver, and spleen. The CFTR protein was higher in treated monkeys than in an untreated monkey. GFP protein was detected in treated lungs. Lung surface and keratin 5-positive basal cells showed higher CFTR staining than in the uninfected monkey and were positive for GFP staining, indicating widespread gene transduction by AAV1CFTR and GFP. AAV1 safely and effectively transduces monkey airway and basal cells. Both the significant numbers of vector genomes and transduction from AAV1CFTR and GFP virus seen in the monkeys 3 months after the first instillation suggest that repeat dosing with AAV1-based vectors is achievable.
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Affiliation(s)
- William B Guggino
- Departments of Medicine and Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Murali K Yanda
- Departments of Medicine and Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Cristina V Cebotaru
- Departments of Medicine and Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Liudmila Cebotaru
- Departments of Medicine and Physiology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
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32
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Visuvanathan S, Baker AN, Lagali PS, Coupland SG, Miller G, Hauswirth WW, Tsilfidis C. XIAP gene therapy effects on retinal ganglion cell structure and function in a mouse model of glaucoma. Gene Ther 2021; 29:147-156. [PMID: 34363035 DOI: 10.1038/s41434-021-00281-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 07/07/2021] [Accepted: 07/15/2021] [Indexed: 11/09/2022]
Abstract
Glaucoma is a prevalent neurodegenerative disease that is characterized by progressive visual field loss. It is the leading cause of irreversible blindness in the world. The main risk factor for glaucoma is elevated intraocular pressure that results in the damage and death of retinal ganglion cells (RGCs) and their axons. The death of RGCs has been shown to be apoptotic. We tested the hypothesis that blocking the activation of apoptosis may be an effective strategy to prevent RGC death and preserve functional vision in glaucoma. In the magnetic microbead mouse model of induced ocular hypertension, inhibition of RGC apoptosis was targeted through viral-mediated ocular delivery of the X-linked inhibitor of apoptosis (XIAP) gene, a potent caspase inhibitor. Pattern electroretinograms revealed that XIAP therapy resulted in significant protection of both somal and axonal RGC function in glaucomatous eyes. Histology confirmed that the treated optic nerves showed preservation of axon counts and reduced glial cell infiltration. These results show that XIAP is able to provide both functional and structural protection of RGCs in the microbead model of glaucoma and provide important proof-of-principle for XIAP's efficacy as a neuroprotective treatment for glaucoma.
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Affiliation(s)
- Shagana Visuvanathan
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Adam N Baker
- Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Pamela S Lagali
- Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Stuart G Coupland
- Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada.,Regenerative Medicine, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,Department of Ophthalmology, University of Ottawa, Ottawa, ON, Canada
| | - Garfield Miller
- Regenerative Medicine, Ottawa Hospital Research Institute, Ottawa, ON, Canada.,Department of Ophthalmology, University of Ottawa, Ottawa, ON, Canada
| | - William W Hauswirth
- Department of Ophthalmology, University of Florida College of Medicine, Gainesville, FL, USA
| | - Catherine Tsilfidis
- Neuroscience, Ottawa Hospital Research Institute, Ottawa, ON, Canada. .,Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada. .,Department of Ophthalmology, University of Ottawa, Ottawa, ON, Canada.
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33
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Gilkes JA, Judkins BL, Herrera BN, Mandel RJ, Boye SL, Boye SE, Srivastava A, Heldermon CD. Site-specific modifications to AAV8 capsid yields enhanced brain transduction in the neonatal MPS IIIB mouse. Gene Ther 2021; 28:447-455. [PMID: 33244179 PMCID: PMC8149485 DOI: 10.1038/s41434-020-00206-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 09/03/2020] [Accepted: 10/19/2020] [Indexed: 12/16/2022]
Abstract
Mucopolysaccharidosis type IIIB (MPS IIIB) is an autosomal recessive lysosomal disease caused by defective production of the enzyme α-N-acetylglucosaminidase. It is characterized by severe and complex central nervous system degeneration. Effective therapies will likely target early onset disease and overcome the blood-brain barrier. Modifications of adeno-associated viral (AAV) vector capsids that enhance transduction efficiency have been described in the retina. Herein, we describe for the first time, a transduction assessment of two intracranially administered adeno-associated virus serotype 8 variants, in which specific surface-exposed tyrosine (Y) and threonine (T) residues were substituted with phenylalanine (F) and valine (V) residues, respectively. A double-mutant (Y444 + 733F) and a triple-mutant (Y444 + 733F + T494V) AAV8 were evaluated for their efficacy for the potential treatment of MPS IIIB in a neonatal setting. We evaluated biodistribution and transduction profiles of both variants compared to the unmodified parental AAV8, and assessed whether the method of vector administration would modulate their utility. Vectors were administered through four intracranial routes: six sites (IC6), thalamic (T), intracerebroventricular, and ventral tegmental area into neonatal mice. Overall, we conclude that the IC6 method resulted in the widest biodistribution within the brain. Noteworthy, we demonstrate that GFP intensity was significantly more robust with AAV8 (double Y-F + T-V) compared to AAV8 (double Y-F). This provides proof of concept for the enhanced utility of IC6 administration of the capsid modified AAV8 (double Y-F + T-V) as a valid therapeutic approach for the treatment of MPS IIIB, with further implications for other monogenic diseases.
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Affiliation(s)
- Janine A Gilkes
- Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - Benjamin L Judkins
- Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - Brontie N Herrera
- Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA
| | - Ronald J Mandel
- Department of Neuroscience, University of Florida College of Medicine, Gainesville, FL, USA
| | - Sanford L Boye
- Department of Pediatrics, Powell Gene Therapy Center, University of Florida College of Medicine, Gainesville, FL, USA
| | - Shannon E Boye
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida College of Medicine, Gainesville, FL, USA
| | - Arun Srivastava
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida College of Medicine, Gainesville, FL, USA
| | - Coy D Heldermon
- Department of Medicine, University of Florida College of Medicine, Gainesville, FL, USA.
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34
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Abaandou L, Quan D, Shiloach J. Affecting HEK293 Cell Growth and Production Performance by Modifying the Expression of Specific Genes. Cells 2021; 10:cells10071667. [PMID: 34359846 PMCID: PMC8304725 DOI: 10.3390/cells10071667] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 06/24/2021] [Accepted: 06/28/2021] [Indexed: 12/22/2022] Open
Abstract
The HEK293 cell line has earned its place as a producer of biotherapeutics. In addition to its ease of growth in serum-free suspension culture and its amenability to transfection, this cell line’s most important attribute is its human origin, which makes it suitable to produce biologics intended for human use. At the present time, the growth and production properties of the HEK293 cell line are inferior to those of non-human cell lines, such as the Chinese hamster ovary (CHO) and the murine myeloma NSO cell lines. However, the modification of genes involved in cellular processes, such as cell proliferation, apoptosis, metabolism, glycosylation, secretion, and protein folding, in addition to bioprocess, media, and vector optimization, have greatly improved the performance of this cell line. This review provides a comprehensive summary of important achievements in HEK293 cell line engineering and on the global engineering approaches and functional genomic tools that have been employed to identify relevant genes for targeted engineering.
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Affiliation(s)
- Laura Abaandou
- Biotechnology Core Laboratory National Institutes of Diabetes, Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA; (L.A.); (D.Q.)
- Department of Chemistry and Biochemistry, College of Science, George Mason University, Fairfax, VA 22030, USA
| | - David Quan
- Biotechnology Core Laboratory National Institutes of Diabetes, Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA; (L.A.); (D.Q.)
| | - Joseph Shiloach
- Biotechnology Core Laboratory National Institutes of Diabetes, Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA; (L.A.); (D.Q.)
- Correspondence:
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35
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Erythropoietin Gene Therapy Delays Retinal Degeneration Resulting from Oxidative Stress in the Retinal Pigment Epithelium. Antioxidants (Basel) 2021; 10:antiox10060842. [PMID: 34070383 PMCID: PMC8229633 DOI: 10.3390/antiox10060842] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2021] [Revised: 05/19/2021] [Accepted: 05/23/2021] [Indexed: 02/08/2023] Open
Abstract
Erythropoietin (EPO) plays an important role in erythropoiesis by its action in blocking apoptosis of progenitor cells and protects both photoreceptors and retinal ganglion cells from induced or inherited degeneration. A modified form of EPO, EPO-R76E has attenuated erythropoietic activity but is effective in inhibiting apoptosis, oxidative stress, and inflammation in several models of retinal degeneration. In this study, we used recombinant Adeno Associated Virus (AAV) to provide long-term sustained delivery of EPO-R76E and demonstrated its effects in a mouse model of dry-AMD in which retinal degeneration is induced by oxidative stress in the retinal pigment epithelial (RPE) cells. Experimental vector AAV-EPO-R76E and control vector AAV-GFP were packaged into serotype-1 (AAV1) to enable RPE selective expression. RPE oxidative stress-mediated retinal degeneration was induced by exon specific deletion of the protective enzyme MnSOD (encoded by Sod2) by cre/lox mechanism. Experimental mice received subretinal injection of AAV-EPO-R76E in the right eye and AAV-GFP in the left eye. Western blotting of RPE/choroid protein samples from AAV-EPO-R76E injected eyes showed RPE specific EPO expression. Retinal function was monitored by electroretinography (ERG). EPO-R76E over-expression in RPE delayed the retinal degeneration as measured by light microscopy in RPE specific Sod2 knockout mice. Delivery of EPO-R76E vector can be used as a tool to prevent retinal degeneration induced by RPE oxidative stress, which is implicated as a potential cause of Age-Related Macular Degeneration.
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36
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Corey EA, Zolotukhin S, Ache BW, Ukhanov K. Mixture interactions at mammalian olfactory receptors are dependent on the cellular environment. Sci Rep 2021; 11:9278. [PMID: 33927269 PMCID: PMC8085013 DOI: 10.1038/s41598-021-88601-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 04/07/2021] [Indexed: 02/02/2023] Open
Abstract
Functional characterization of mammalian olfactory receptors (ORs) remains a major challenge to ultimately understanding the olfactory code. Here, we compare the responses of the mouse Olfr73 ectopically expressed in olfactory sensory neurons using AAV gene delivery in vivo and expressed in vitro in cell culture. The response dynamics and concentration-dependence of agonists for the ectopically expressed Olfr73 were similar to those reported for the endogenous Olfr73, however the antagonism previously reported between its cognate agonist and several antagonists was not replicated in vivo. Expressing the OR in vitro reproduced the antagonism reported for short odor pulses, but not for prolonged odor exposure. Our findings suggest that both the cellular environment and the stimulus dynamics shape the functionality of Olfr73 and argue that characterizing ORs in 'native' conditions, rather than in vitro, provides a more relevant understanding of ligand-OR interactions.
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Affiliation(s)
- Elizabeth A Corey
- Whitney Laboratory, University of Florida, Gainesville, FL, USA
- Center for Smell and Taste, University of Florida, Gainesville, FL, USA
| | - Sergei Zolotukhin
- Department of Pediatrics, University of Florida, Gainesville, FL, USA
- Center for Smell and Taste, University of Florida, Gainesville, FL, USA
| | - Barry W Ache
- Whitney Laboratory, University of Florida, Gainesville, FL, USA
- Department of Biology and Neuroscience, University of Florida, Gainesville, FL, USA
- Center for Smell and Taste, University of Florida, Gainesville, FL, USA
- McKnight Brain Institute, University of Florida, Gainesville, FL, USA
| | - Kirill Ukhanov
- Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, USA.
- Center for Smell and Taste, University of Florida, Gainesville, FL, USA.
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37
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Effects of Altering HSPG Binding and Capsid Hydrophilicity on Retinal Transduction by AAV. J Virol 2021; 95:JVI.02440-20. [PMID: 33658343 PMCID: PMC8139652 DOI: 10.1128/jvi.02440-20] [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: 11/20/2022] Open
Abstract
Adeno-associated viruses (AAVs) have recently emerged as the leading vector for retinal gene therapy. However, AAV vectors which are capable of achieving clinically relevant levels of transgene expression and widespread retinal transduction are still an unmet need. Using rationally designed AAV2-based capsid variants, we investigate the role of capsid hydrophilicity and hydrophobicity as it relates to retinal transduction. We show that hydrophilic, single amino acid (aa) mutations (V387R, W502H, E530K, L583R) in AAV2 negatively impact retinal transduction when heparan sulfate proteoglycan (HSPG) binding remains intact. Conversely, addition of hydrophobic point mutations to an HSPG binding deficient capsid (AAV2ΔHS) lead to increased retinal transduction in both mouse and macaque. Our top performing vector, AAV2(4pMut)ΔHS, achieved robust rod and cone photoreceptor (PR) transduction in macaque, especially in the fovea, and demonstrates the ability to spread laterally beyond the borders of the subretinal injection (SRI) bleb. This study both evaluates biophysical properties of AAV capsids that influence retinal transduction, and assesses the transduction and tropism of a novel capsid variant in a clinically relevant animal model.ImportanceRationally guided engineering of AAV capsids aims to create new generations of vectors with enhanced potential for human gene therapy. By applying rational design principles to AAV2-based capsids, we evaluated the influence of hydrophilic and hydrophobic amino acid (aa) mutations on retinal transduction as it relates to vector administration route. Through this approach we identified a largely deleterious relationship between hydrophilic aa mutations and canonical HSPG binding by AAV2-based capsids. Conversely, the inclusion of hydrophobic aa substitutions on a HSPG binding deficient capsid (AAV2ΔHS), generated a vector capable of robust rod and cone photoreceptor (PR) transduction. This vector AAV2(4pMut)ΔHS also demonstrates a remarkable ability to spread laterally beyond the initial subretinal injection (SRI) bleb, making it an ideal candidate for the treatment of retinal diseases which require a large area of transduction.
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38
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Fuller-Carter PI, Basiri H, Harvey AR, Carvalho LS. Focused Update on AAV-Based Gene Therapy Clinical Trials for Inherited Retinal Degeneration. BioDrugs 2021; 34:763-781. [PMID: 33136237 DOI: 10.1007/s40259-020-00453-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Inherited retinal diseases (IRDs) comprise a clinically and genetically heterogeneous group of disorders that can ultimately result in photoreceptor dysfunction/death and vision loss. With over 270 genes known to be involved in IRDs, translation of treatment strategies into clinical applications has been historically difficult. However, in recent years there have been significant advances in basic research findings as well as translational studies, culminating in an increasing number of clinical trials with the ultimate goal of reducing vision loss and associated morbidities. The recent approval of Luxturna® (voretigene neparvovec-rzyl) for Leber congenital amaurosis type 2 (LCA2) prompts a review of the current clinical trials for IRDs, with a particular focus on the importance of adeno-associated virus (AAV)-based gene therapies. The present article reviews the current state of AAV use in gene therapy clinical trials for IRDs, with a brief background on AAV and the reasons behind its dominance in ocular gene therapy. It will also discuss pre-clinical progress in AAV-based therapies aimed at treating other ocular conditions that can have hereditable links, and what alternative technologies are progressing in the same therapeutic space.
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Affiliation(s)
- Paula I Fuller-Carter
- Centre for Ophthalmology and Visual Sciences (Incorporating Lions Eye Institute), The University of Western Australia, Nedlands, WA, Australia
| | - Hamed Basiri
- Centre for Ophthalmology and Visual Sciences (Incorporating Lions Eye Institute), The University of Western Australia, Nedlands, WA, Australia
| | - Alan R Harvey
- School of Human Sciences, The University of Western Australia, Crawley, WA, Australia.,Perron Institute for Neurological and Translational Science, 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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39
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Srivastava A, Mallela KMG, Deorkar N, Brophy G. Manufacturing Challenges and Rational Formulation Development for AAV Viral Vectors. J Pharm Sci 2021; 110:2609-2624. [PMID: 33812887 DOI: 10.1016/j.xphs.2021.03.024] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 03/19/2021] [Accepted: 03/30/2021] [Indexed: 12/19/2022]
Abstract
Adeno-associated virus (AAV) has emerged as a leading platform for gene delivery for treating various diseases due to its excellent safety profile and efficient transduction to various target tissues. However, the large-scale production and long-term storage of viral vectors is not efficient resulting in lower yields, moderate purity, and shorter shelf-life compared to recombinant protein therapeutics. This review provides a comprehensive analysis of upstream, downstream and formulation unit operation challenges encountered during AAV vector manufacturing, and discusses how desired product quality attributes can be maintained throughout product shelf-life by understanding the degradation mechanisms and formulation strategies. The mechanisms of various physical and chemical instabilities that the viral vector may encounter during its production and shelf-life because of various stressed conditions such as thermal, shear, freeze-thaw, and light exposure are highlighted. The role of buffer, pH, excipients, and impurities on the stability of viral vectors is also discussed. As such, the aim of this review is to outline the tools and a potential roadmap for improving the quality of AAV-based drug products by stressing the need for a mechanistic understanding of the involved processes.
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Affiliation(s)
- Arvind Srivastava
- Biopharma Production, Avantor, Inc., 1013 US Highway, 202/206, Bridgewater, NJ, United States.
| | - Krishna M G Mallela
- Center for Pharmaceutical Biotechnology, Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, 12850 East Montview Boulevard, MS C238-V20, Aurora, CO 80045, United States.
| | - Nandkumar Deorkar
- Biopharma Production, Avantor, Inc., 1013 US Highway, 202/206, Bridgewater, NJ, United States
| | - Ger Brophy
- Biopharma Production, Avantor, Inc., 1013 US Highway, 202/206, Bridgewater, NJ, United States
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40
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Gene therapy reforms photoreceptor structure and restores vision in NPHP5-associated Leber congenital amaurosis. Mol Ther 2021; 29:2456-2468. [PMID: 33781914 DOI: 10.1016/j.ymthe.2021.03.021] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 12/21/2020] [Accepted: 03/23/2021] [Indexed: 02/03/2023] Open
Abstract
The inherited childhood blindness caused by mutations in NPHP5, a form of Leber congenital amaurosis, results in abnormal development, dysfunction, and degeneration of photoreceptors. A naturally occurring NPHP5 mutation in dogs leads to a phenotype that very nearly duplicates the human retinopathy in terms of the photoreceptors involved, spatial distribution of degeneration, and the natural history of vision loss. We show that adeno-associated virus (AAV)-mediated NPHP5 gene augmentation of mutant canine retinas at the time of active degeneration and peak cell death stably restores photoreceptor structure, function, and vision with either the canine or human NPHP5 transgenes. Mutant cone photoreceptors, which failed to form outer segments during development, reform this structure after treatment. Degenerating rod photoreceptor outer segments are stabilized and develop normal structure. This process begins within 8 weeks after treatment and remains stable throughout the 6-month posttreatment period. In both photoreceptor cell classes mislocalization of rod and cone opsins is minimized or reversed. Retinal function and functional vision are restored. Efficacy of gene therapy in this large animal ciliopathy model of Leber congenital amaurosis provides a path for translation to human treatment.
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41
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Joshi PRH, Bernier A, Moço PD, Schrag J, Chahal PS, Kamen A. Development of a scalable and robust AEX method for enriched rAAV preparations in genome-containing VCs of serotypes 5, 6, 8, and 9. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2021; 21:341-356. [PMID: 33898632 PMCID: PMC8056178 DOI: 10.1016/j.omtm.2021.03.016] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 03/18/2021] [Indexed: 11/25/2022]
Abstract
Removal of empty capsids from adeno-associated virus (AAV) manufacturing lots remains a critical step in the downstream processing of AAV clinical-grade batches. Because of similar physico-chemical characteristics, the AAV capsid populations totally lacking or containing partial viral DNA are difficult to separate from the desired vector capsid populations. Based on minute differences in density, ultracentrifugation remains the most effective separation method and has been extensively used at small scale but has limitations associated with availabilities and operational complexities in large-scale processing. In this paper, we report a scalable, robust, and versatile anion-exchange chromatography (AEX) method for removing empty capsids and subsequent enrichment of vectors of AAV serotypes 5, 6, 8, and 9. On average, AEX resulted in about 9-fold enrichment of AAV5 in a single step containing 80% ± 5% genome-containing vector capsids, as verified and quantified by analytical ultracentrifugation. The optimized process was further validated using AAV6, AAV8, and AAV9, resulting in over 90% vector enrichment. The AEX process showed comparable results not only for vectors with different transgenes of different sizes but also for AEX runs under different geometries of chromatographic media. The herein-reported sulfate-salt-based AEX process can be adapted to different AAV serotypes by appropriately adjusting elution conditions to achieve enriched vector preparations.
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Affiliation(s)
- Pranav R H Joshi
- Viral Vectors and Vaccine Bioprocessing Group, Department of Bioengineering, McGill University, Montreal, QC, Canada
| | - Alice Bernier
- Viral Vectors and Vaccine Bioprocessing Group, Department of Bioengineering, McGill University, Montreal, QC, Canada
| | - Pablo D Moço
- Viral Vectors and Vaccine Bioprocessing Group, Department of Bioengineering, McGill University, Montreal, QC, Canada
| | - Joseph Schrag
- Human Health Therapeutics, National Research Council of Canada, Montreal, QC, Canada
| | - Parminder S Chahal
- Human Health Therapeutics, National Research Council of Canada, Montreal, QC, Canada
| | - Amine Kamen
- Viral Vectors and Vaccine Bioprocessing Group, Department of Bioengineering, McGill University, Montreal, QC, Canada
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42
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Duarte Azevedo M, Sander S, Jeanneret C, Olfat S, Tenenbaum L. Selective targeting of striatal parvalbumin-expressing interneurons for transgene delivery. J Neurosci Methods 2021; 354:109105. [PMID: 33652020 DOI: 10.1016/j.jneumeth.2021.109105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 02/12/2021] [Accepted: 02/14/2021] [Indexed: 01/17/2023]
Abstract
PVCre mice--> combined with AAV-FLEX vectors allowed efficient and specific targeting of PV+ interneurons in the striatum. However, diffusion of viral particles to the globus pallidus caused massive transduction of PV+ projection neurons and subsequent anterograde transport of the transgene product to the subthalamic nucleus and the substantia nigra pars reticulata. Different AAV serotypes (1 and 9) and promoters (CBA and human synapsin) were evaluated. The combination of AAV1, a moderate expression level (human synapsin promoter) and a precise adjustment of the stereotaxic coordinates in the anterior and dorsolateral part of the striatum were necessary to avoid transduction of PV+ GP projection neurons. Even in the absence of direct transduction due to diffusion of viral particles, GP PV+ projection neurons could be retrogradely transduced via their terminals present in the dorsal striatum. However, in the absence of diffusion, GP-Str PV+ projection neurons were poorly or not transduced suggesting that retrograde transduction did not significantly impair the selective targeting of striatal PV+ neurons. Finally, a prominent reduction of the number of striatal PV+ interneurons (about 50 %) was evidenced in the presence of the Cre recombinase suggesting that functional effects of AAV-mediated transgene expression in PV+ striatal interneurons in PVCre mice should be analyzed with caution.
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Affiliation(s)
- Marcelo Duarte Azevedo
- Laboratory of Cellular and Molecular Neurotherapies, Center for Neuroscience Research, Clinical Neurosciences Department, Lausanne University Hospital, Switzerland
| | - Sibilla Sander
- Laboratory of Cellular and Molecular Neurotherapies, Center for Neuroscience Research, Clinical Neurosciences Department, Lausanne University Hospital, Switzerland
| | - Cheryl Jeanneret
- Laboratory of Cellular and Molecular Neurotherapies, Center for Neuroscience Research, Clinical Neurosciences Department, Lausanne University Hospital, Switzerland
| | - Soophie Olfat
- Laboratory of Cellular and Molecular Neurotherapies, Center for Neuroscience Research, Clinical Neurosciences Department, Lausanne University Hospital, Switzerland
| | - Liliane Tenenbaum
- Laboratory of Cellular and Molecular Neurotherapies, Center for Neuroscience Research, Clinical Neurosciences Department, Lausanne University Hospital, Switzerland.
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Lowell JA, Mah KM, Bixby JL, Lemmon VP. AAV8 transduction capacity is reduced by prior exposure to endosome-like pH conditions. Neural Regen Res 2021; 16:851-855. [PMID: 33229719 PMCID: PMC8178773 DOI: 10.4103/1673-5374.299272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Adeno-associated virus (AAV) is an essential instrument in the neuroscientist's toolkit, which allows delivery of DNA to provide labeling with fluorescent proteins or genetic instructions to regulate gene expression. In the field of neural regeneration, the transduction of neurons enables the observation and regulation of axon growth and regeneration, and in the future will likely be a mechanism for delivering molecular therapies to promote sprouting and regeneration after central nervous system injury. Traditional formulations of AAV preparations permit efficient viral transduction under physiologic conditions, but an improved understanding of the mechanistic limitations of AAV transduction may facilitate production of more resilient AAV strains for investigative and therapeutic purposes. We studied AAV transduction in the context of prior exposure of AAV serotype 8 (AAV8) to environmental pH within the range encountered during endosomal endocytosis (pH 7.4 to pH 4.4), during which low pH-triggered structural and autoproteolytic changes to the viral capsid are believed to be necessary for endosome escape and virus uncoating. Due to the fundamental nature of these processes, we hypothesized that premature exposure of AAV8 particles to acidic pH would decrease viral transduction of HT1080 cells in vitro, as measured by fluorescent reporter gene expression using high-content imaging analysis. We found that increasingly acidic incubation conditions were associated with concomitant reductions in transduction efficiency, and that quantitative levels of reporter gene expression in transduced cells were similarly decreased. The biggest decrease in transduction occurred between pH 7.4 and pH 6.4, suggesting the possible co-occurrence of a pH-associated event and viral inactivation within that range. Taken together, these findings indicate that exposure of AAV8 to acidic pH for as little as 1 hour is deleterious to transduction ability. Future studies are necessary to understand the pH-associated causative mechanisms involved. This study was approved by the University of Miami Institutional Animal Care and Use Committee, USA (Protocol #18-108-LF) on July 12, 2018.
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Affiliation(s)
- Jeffrey A Lowell
- Miami Project to Cure Paralysis, University of Miami, Miami, FL, USA
| | - Kar Men Mah
- Miami Project to Cure Paralysis, University of Miami, Miami, FL, USA
| | - John L Bixby
- Miami Project to Cure Paralysis; Department of Neurological Surgery; Department of Molecular and Cellular Pharmacology, University of Miami, Miami, FL, USA
| | - Vance P Lemmon
- Miami Project to Cure Paralysis; Department of Neurological Surgery, University of Miami, Miami, FL, USA
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44
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Corey EA, Ukhanov K, Bobkov YV, McIntyre JC, Martens JR, Ache BW. Inhibitory signaling in mammalian olfactory transduction potentially mediated by Gα o. Mol Cell Neurosci 2020; 110:103585. [PMID: 33358996 DOI: 10.1016/j.mcn.2020.103585] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 11/27/2020] [Accepted: 12/09/2020] [Indexed: 01/12/2023] Open
Abstract
Olfactory GPCRs (ORs) in mammalian olfactory receptor neurons (ORNs) mediate excitation through the Gαs family member Gαolf. Here we tentatively associate a second G protein, Gαo, with inhibitory signaling in mammalian olfactory transduction by first showing that odor evoked phosphoinositide 3-kinase (PI3K)-dependent inhibition of signal transduction is absent in the native ORNs of mice carrying a conditional OMP-Cre based knockout of Gαo. We then identify an OR from native rat ORNs that are activated by octanol through cyclic nucleotide signaling and inhibited by citral in a PI3K-dependent manner. We show that the OR activates cyclic nucleotide signaling and PI3K signaling in a manner that reflects its functionality in native ORNs. Our findings lay the groundwork to explore the interesting possibility that ORs can interact with two different G proteins in a functionally identified, ligand-dependent manner to mediate opponent signaling in mature mammalian ORNs.
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Affiliation(s)
- Elizabeth A Corey
- Whitney Laboratory, Center for Smell and Taste, University of Florida, Gainesville, FL 32610, United States of America
| | - Kirill Ukhanov
- Dept. of Pharmacology and Therapeutics, Center for Smell and Taste, University of Florida, Gainesville, FL 32610, United States of America
| | - Yuriy V Bobkov
- Whitney Laboratory, Center for Smell and Taste, University of Florida, Gainesville, FL 32610, United States of America
| | - Jeremy C McIntyre
- Dept. of Neuroscience, Center for Smell and Taste, University of Florida, Gainesville, FL 32610, United States of America
| | - Jeffrey R Martens
- Dept. of Pharmacology and Therapeutics, Center for Smell and Taste, University of Florida, Gainesville, FL 32610, United States of America
| | - Barry W Ache
- Whitney Laboratory, Dept. of Biology, Center for Smell and Taste, University of Florida, Gainesville, FL 32610, United States of America; Whitney Laboratory, Dept. of Neuroscience, Center for Smell and Taste, University of Florida, Gainesville, FL 32610, United States of America.
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45
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Lugin ML, Lee RT, Kwon YJ. Synthetically Engineered Adeno-Associated Virus for Efficient, Safe, and Versatile Gene Therapy Applications. ACS NANO 2020; 14:14262-14283. [PMID: 33073995 DOI: 10.1021/acsnano.0c03850] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Gene therapy directly targets mutations causing disease, allowing for a specific treatment at a molecular level. Adeno-associated virus (AAV) has been of increasing interest as a gene delivery vehicle, as AAV vectors are safe, effective, and capable of eliciting a relatively contained immune response. With the recent FDA approval of two AAV drugs for treating rare genetic diseases, AAV vectors are now on the market and are being further explored for other therapies. While showing promise in immune privileged tissue, the use of AAV for systemic delivery is still limited due to the high prevalence of neutralizing antibodies (nAbs). To avoid nAb-mediated inactivation, engineered AAV vectors with modified protein capsids, materials tethered to the capsid surface, or fully encapsulated in a second, larger carrier have been explored. Many of these engineered AAVs have added benefits, including avoided immune response, overcoming the genome size limit, targeted and stimuli-responsive delivery, and multimodal therapy of two or more therapeutic modalities in one platform. Native and engineered AAV vectors have been tested to treat a broad range of diseases, including spinal muscular atrophy, retinal diseases, cancers, and tissue damage. This review will cover the benefits of AAV as a promising gene vector by itself, the progress and advantages of engineered AAV vectors, particularly synthetically engineered ones, and the current state of their clinical translation in therapy.
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Sasaki Y, Kakita H, Kubota S, Sene A, Lee TJ, Ban N, Dong Z, Lin JB, Boye SL, DiAntonio A, Boye SE, Apte RS, Milbrandt J. SARM1 depletion rescues NMNAT1-dependent photoreceptor cell death and retinal degeneration. eLife 2020; 9:e62027. [PMID: 33107823 PMCID: PMC7591247 DOI: 10.7554/elife.62027] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 10/13/2020] [Indexed: 01/02/2023] Open
Abstract
Leber congenital amaurosis type nine is an autosomal recessive retinopathy caused by mutations of the NAD+ synthesis enzyme NMNAT1. Despite the ubiquitous expression of NMNAT1, patients do not manifest pathologies other than retinal degeneration. Here we demonstrate that widespread NMNAT1 depletion in adult mice mirrors the human pathology, with selective loss of photoreceptors highlighting the exquisite vulnerability of these cells to NMNAT1 loss. Conditional deletion demonstrates that NMNAT1 is required within the photoreceptor. Mechanistically, loss of NMNAT1 activates the NADase SARM1, the central executioner of axon degeneration, to trigger photoreceptor death and vision loss. Hence, the essential function of NMNAT1 in photoreceptors is to inhibit SARM1, highlighting an unexpected shared mechanism between axonal degeneration and photoreceptor neurodegeneration. These results define a novel SARM1-dependent photoreceptor cell death pathway and identifies SARM1 as a therapeutic candidate for retinopathies.
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Affiliation(s)
- Yo Sasaki
- Department of Genetics, Washington University School of MedicineSt. LouisUnited States
| | - Hiroki Kakita
- Department of Genetics, Washington University School of MedicineSt. LouisUnited States
- Department of Perinatal and Neonatal Medicine, Aichi Medical UniversityAichiJapan
| | - Shunsuke Kubota
- Department of Ophthalmology and Visual Sciences, Washington University School of MedicineSt. LouisUnited States
| | - Abdoulaye Sene
- Department of Ophthalmology and Visual Sciences, Washington University School of MedicineSt. LouisUnited States
| | - Tae Jun Lee
- Department of Ophthalmology and Visual Sciences, Washington University School of MedicineSt. LouisUnited States
| | - Norimitsu Ban
- Department of Ophthalmology and Visual Sciences, Washington University School of MedicineSt. LouisUnited States
| | - Zhenyu Dong
- Department of Ophthalmology and Visual Sciences, Washington University School of MedicineSt. LouisUnited States
| | - Joseph B Lin
- Department of Ophthalmology and Visual Sciences, Washington University School of MedicineSt. LouisUnited States
| | - Sanford L Boye
- Department of Pediatrics, Powell Gene Therapy CenterGainesvilleUnited States
| | - Aaron DiAntonio
- Department of Developmental Biology, Washington University School of MedicineSt. LouisUnited States
- Needleman Center for Neurometabolism and Axonal TherapeuticsSt. LouisUnited States
| | - Shannon E Boye
- Department of Pediatrics, Division of Cellular and Molecular TherapyGainesvilleUnited States
| | - Rajendra S Apte
- Department of Ophthalmology and Visual Sciences, Washington University School of MedicineSt. LouisUnited States
- Department of Developmental Biology, Washington University School of MedicineSt. LouisUnited States
- Department of Medicine, Washington University School of MedicineSt. LouisUnited States
| | - Jeffrey Milbrandt
- Department of Genetics, Washington University School of MedicineSt. LouisUnited States
- Needleman Center for Neurometabolism and Axonal TherapeuticsSt. LouisUnited States
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47
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Mietzsch M, Smith JK, Yu JC, Banala V, Emmanuel SN, Jose A, Chipman P, Bhattacharya N, McKenna R, Agbandje-McKenna M. Characterization of AAV-Specific Affinity Ligands: Consequences for Vector Purification and Development Strategies. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2020; 19:362-373. [PMID: 33145372 PMCID: PMC7591348 DOI: 10.1016/j.omtm.2020.10.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 10/01/2020] [Indexed: 02/06/2023]
Abstract
Affinity-based purification of adeno-associated virus (AAV) vectors has replaced density-based methods for vectors used in clinical settings. This method utilizes camelid single-domain antibodies recognizing AAV capsids. These include AVB Sepharose (AVB) and POROS CaptureSelect affinity ligand for AAV8 (CSAL8) and AAV9 (CSAL9). In this study, we utilized cryo-electron microscopy and 3D image reconstruction to map the binding sites of these affinity ligands on the capsids of several AAV serotypes, including AAV1, AAV2, AAV5, AAV8, and AAV9, representing the range of sequence and structure diversity among AAVs. The AAV-ligand complex structures showed that AVB and CSAL9 bound to the 5-fold capsid region, although in different orientations, and CSAL8 bound to the side of the 3-fold protrusion. The AAV contact residues required for ligand binding, and thus AAV purification, and the ability of the ligands to neutralize infection were analyzed. The data show that only a few residues within the epitopes served to block affinity ligand binding. Neutralization was observed for AAV1 and AAV5 with AVB, for AAV1 with CSAL8, and for AAV9 with CSAL9, associated with regions that overlap with epitopes for neutralizing monoclonal antibodies against these capsids. This information is critical and could be generally applicable in the development of novel AAV vectors amenable to affinity column purification.
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Affiliation(s)
- Mario Mietzsch
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - J Kennon Smith
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Jennifer C Yu
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Vibhu Banala
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Shanan N Emmanuel
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Ariana Jose
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Paul Chipman
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Nilakshee Bhattacharya
- Biological Science Imaging Resource, Department of Biological Sciences, Florida State University, Tallahassee, FL, USA
| | - Robert McKenna
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
| | - Mavis Agbandje-McKenna
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, McKnight Brain Institute, College of Medicine, University of Florida, Gainesville, FL, USA
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48
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Crosson SM, Marques A, Dib P, Dotson CD, Munger SD, Zolotukhin S. Taste Receptor Cells in Mice Express Receptors for the Hormone Adiponectin. Chem Senses 2020; 44:409-422. [PMID: 31125082 DOI: 10.1093/chemse/bjz030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The metabolic hormone adiponectin is secreted into the circulation by adipocytes and mediates key biological functions, including insulin sensitivity, adipocyte development, and fatty acid oxidation. Adiponectin is also abundant in saliva, where its functions are poorly understood. Here we report that murine taste receptor cells (TRCs) express specific adiponectin receptors and may be a target for salivary adiponectin. This is supported by the presence of all three known adiponectin receptors in transcriptomic data obtained by RNA-seq analysis of purified circumvallate (CV) taste buds. As well, immunohistochemical analysis of murine CV papillae showed that two adiponectin receptors, ADIPOR1 and T-cadherin, are localized to subsets of TRCs. Immunofluorescence for T-cadherin was primarily co-localized with the Type 2 TRC marker phospholipase C β2, suggesting that adiponectin signaling could impact sweet, bitter, or umami taste signaling. However, adiponectin null mice showed no differences in behavioral lick responsiveness compared with wild-type controls in brief-access lick testing. AAV-mediated overexpression of adiponectin in the salivary glands of adiponectin null mice did result in a small but significant increase in behavioral lick responsiveness to the fat emulsion Intralipid. Together, these results suggest that salivary adiponectin can affect TRC function, although its impact on taste responsiveness and peripheral taste coding remains unclear.
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Affiliation(s)
- Sean M Crosson
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida, Gainesville, FL, USA.,Center for Smell and Taste, University of Florida, Gainesville, FL, USA.,Graduate Program in Biomedical Sciences, University of Florida, Gainesville, FL, USA
| | - Andrew Marques
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida, Gainesville, FL, USA
| | - Peter Dib
- Graduate Program in Biomedical Sciences, University of Florida, Gainesville, FL, USA.,Department of Anatomy and Cell Biology, University of Florida, Gainesville, FL, USA
| | - Cedrick D Dotson
- Center for Smell and Taste, University of Florida, Gainesville, FL, USA.,Department of Neuroscience, University of Florida, Gainesville, FL, USA
| | - Steven D Munger
- Center for Smell and Taste, University of Florida, Gainesville, FL, USA.,Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, USA.,Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism; University of Florida, Gainesville, FL, USA
| | - Sergei Zolotukhin
- Department of Pediatrics, Division of Cellular and Molecular Therapy, University of Florida, Gainesville, FL, USA.,Center for Smell and Taste, University of Florida, Gainesville, FL, USA
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49
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Mietzsch M, Li Y, Kurian J, Smith JK, Chipman P, McKenna R, Yang L, Agbandje-McKenna M. Structural characterization of a bat Adeno-associated virus capsid. J Struct Biol 2020; 211:107547. [PMID: 32522552 PMCID: PMC9744130 DOI: 10.1016/j.jsb.2020.107547] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Accepted: 06/04/2020] [Indexed: 02/08/2023]
Abstract
Adeno-associated viruses (AAVs) are widespread among vertebrates. AAVs isolated from bats display low capsid protein sequence identities (<60%) to AAV2, AAV5, and other primate AAVs. Here we report the first capsid structure of a non-primate AAV which was isolated from bats. The capsid structure of BtAAV-10HB (10HB) was determined by cryo-electron microscopy and three-dimensional image reconstruction to 3.03 Å resolution. Comparison of empty and genome-containing capsids showed that the capsid structures are almost identical except for an ordered nucleotide in a previously described nucleotide-binding pocket, the density in the 5-fold channel, and several amino acids with altered side chain conformations. Compared to other dependoparvoviruses, for example AAV2 and AAV5, 10HB displays unique structural features including insertions and deletions in capsid surface loops. Overall, the 10HB capsid structure superposes with an RMSD of 1.7 Å and 1.8 Å to AAV2 and AAV5, respectively. Currently all approved AAV human gene therapy biologics and vectors in clinical trials are based on primate isolates. However, pre-existing neutralizing antibodies in the human population represents a hurdle to their use. 10HB capsids are capable of packaging AAV2 vector genomes and thus have potential as gene delivery vectors. Significantly, a screen with human sera showed lack of recognition by the 10HB capsid. Thus, the different capsid surface of 10HB vectors likely renders it "invisible" to potential pre-existing neutralizing human anti-AAV antibodies especially because this virus or similar variants do not exist in primate populations.
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Affiliation(s)
- Mario Mietzsch
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, University of Florida, Gainesville, Florida, USA
| | - Ya Li
- Department of Cardiology and Laboratory of Gene Therapy for Heart Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center for Biotherapy, Chengdu, Sichuan, China
| | - Justin Kurian
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, University of Florida, Gainesville, Florida, USA
| | - James Kennon Smith
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, University of Florida, Gainesville, Florida, USA
| | - Paul Chipman
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, University of Florida, Gainesville, Florida, USA
| | - Robert McKenna
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, University of Florida, Gainesville, Florida, USA
| | - Lin Yang
- Department of Cardiology and Laboratory of Gene Therapy for Heart Diseases, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University and Collaborative Innovation Center for Biotherapy, Chengdu, Sichuan, China
| | - Mavis Agbandje-McKenna
- Department of Biochemistry and Molecular Biology, Center for Structural Biology, The McKnight Brain Institute, University of Florida, Gainesville, Florida, USA,Address correspondence to Mavis Agbandje-McKenna,
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50
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Ross M, Obolensky A, Averbukh E, Ezra-Elia R, Yamin E, Honig H, Dvir H, Rosov A, Hauswirth WW, Gootwine E, Banin E, Ofri R. Evaluation of Photoreceptor Transduction Efficacy of Capsid-Modified Adeno-Associated Viral Vectors Following Intravitreal and Subretinal Delivery in Sheep. Hum Gene Ther 2020; 31:719-729. [PMID: 32486858 DOI: 10.1089/hum.2020.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Gene augmentation therapy based on subretinal delivery of adeno-associated viral (AAV) vectors is proving to be highly efficient in treating several inherited retinal degenerations. However, due to potential complications and drawbacks posed by subretinal injections, there is a great impetus to find alternative methods of delivering the desired genetic inserts to the retina. One such method is an intravitreal delivery of the vector. Our aim was to evaluate the efficacy of two capsid-modified vectors that are less susceptible to cellular degradation, AAV8 (doubleY-F) and AAV2 (quadY-F+T-V), as well as a third, chimeric vector AAV[max], to transduce photoreceptor cells following intravitreal injection in sheep. We further tested whether saturation of inner limiting membrane (ILM) viral binding sites using a nonmodified vector, before the intravitreal injection, would enhance the efficacy of photoreceptor transduction. Only AAV[max] resulted in moderate photoreceptor transduction following intravitreal injection. Intravitreal injection of the two other vectors did not result in photoreceptor transduction nor did the saturation of the ILM before the intravitreal injection. However, two of the vectors efficiently transduced photoreceptor cells following subretinal injection in positive control eyes. Previous trials with the same vectors in both murine and canine models resulted in robust and moderate transduction efficacy, respectively, of photoreceptors following intravitreal delivery, demonstrating the importance of utilizing as many animal models as possible when evaluating new strategies for retinal gene therapy. The successful photoreceptor transduction of AAV[max] injected intravitreally makes it a potential candidate for intravitreal delivery, but further trials are warranted to determine whether the transduction efficacy is sufficient for a clinical outcome.
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Affiliation(s)
- Maya Ross
- Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Alexey Obolensky
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Edward Averbukh
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Raaya Ezra-Elia
- Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, Rehovot, Israel
| | - Esther Yamin
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Hen Honig
- Agricultural Research Organization, The Volcani Center, Rishon LeZion, Israel
| | - Hay Dvir
- Agricultural Research Organization, The Volcani Center, Rishon LeZion, Israel
| | - Alexander Rosov
- Agricultural Research Organization, The Volcani Center, Rishon LeZion, Israel
| | - William W Hauswirth
- Department of Ophthalmology, University of Florida, Gainesville, Florida, USA
| | - Elisha Gootwine
- Agricultural Research Organization, The Volcani Center, Rishon LeZion, Israel
| | - Eyal Banin
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - Ron Ofri
- Koret School of Veterinary Medicine, The Hebrew University of Jerusalem, Rehovot, Israel
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