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Clarke MT, Remesal L, Lentz L, Tan DJ, Young D, Thapa S, Namuduri SR, Borges B, Kirn G, Valencia J, Lopez ME, Lui JH, Shiow LR, Dindot S, Villeda S, Sanders SJ, MacKenzie TC. Prenatal delivery of a therapeutic antisense oligonucleotide achieves broad biodistribution in the brain and ameliorates Angelman syndrome phenotype in mice. Mol Ther 2024; 32:935-951. [PMID: 38327047 PMCID: PMC11163203 DOI: 10.1016/j.ymthe.2024.02.004] [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: 06/24/2023] [Revised: 11/20/2023] [Accepted: 02/02/2024] [Indexed: 02/09/2024] Open
Abstract
Angelman syndrome (AS), an early-onset neurodevelopmental disorder characterized by abnormal gait, intellectual disabilities, and seizures, occurs when the maternal allele of the UBE3A gene is disrupted, since the paternal allele is silenced in neurons by the UBE3A antisense (UBE3A-AS) transcript. Given the importance of early treatment, we hypothesized that prenatal delivery of an antisense oligonucleotide (ASO) would downregulate the murine Ube3a-AS, resulting in increased UBE3A protein and functional rescue. Using a mouse model with a Ube3a-YFP allele that reports on-target ASO activity, we found that in utero, intracranial (IC) injection of the ASO resulted in dose-dependent activation of paternal Ube3a, with broad biodistribution. Accordingly, in utero injection of the ASO in a mouse model of AS also resulted in successful restoration of UBE3A and phenotypic improvements in treated mice on the accelerating rotarod and fear conditioning. Strikingly, even intra-amniotic (IA) injection resulted in systemic biodistribution and high levels of UBE3A reactivation throughout the brain. These findings offer a novel strategy for early treatment of AS using an ASO, with two potential routes of administration in the prenatal window. Beyond AS, successful delivery of a therapeutic ASO into neurons has implications for a clinically feasible prenatal treatment for numerous neurodevelopmental disorders.
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Affiliation(s)
- Maria T Clarke
- Department of Surgery, University of California San Francisco, San Francisco, California, USA; The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, California, USA; Center for Maternal-Fetal Precision Medicine, University of California San Francisco, San Francisco, California, USA
| | - Laura Remesal
- Department of Anatomy, University of California San Francisco, San Francisco, California, USA
| | - Lea Lentz
- Department of Surgery, University of California San Francisco, San Francisco, California, USA; The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, California, USA; Center for Maternal-Fetal Precision Medicine, University of California San Francisco, San Francisco, California, USA
| | | | - David Young
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, California, USA; Institute for Molecular and Cell Biology, Agency for Science, Technology and Research, 138632, Singapore, Singapore
| | - Slesha Thapa
- BioMarin Pharmaceutical, San Rafael, California, USA
| | - Shalini R Namuduri
- Department of Surgery, University of California San Francisco, San Francisco, California, USA; The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, California, USA; Center for Maternal-Fetal Precision Medicine, University of California San Francisco, San Francisco, California, USA
| | - Beltran Borges
- Department of Surgery, University of California San Francisco, San Francisco, California, USA; The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, California, USA; Center for Maternal-Fetal Precision Medicine, University of California San Francisco, San Francisco, California, USA
| | - Georgia Kirn
- Department of Surgery, University of California San Francisco, San Francisco, California, USA; The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, California, USA; Center for Maternal-Fetal Precision Medicine, University of California San Francisco, San Francisco, California, USA
| | - Jasmine Valencia
- Department of Surgery, University of California San Francisco, San Francisco, California, USA; The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, California, USA
| | | | - Jan H Lui
- BioMarin Pharmaceutical, San Rafael, California, USA
| | | | - Scott Dindot
- Department of Veterinary Pathobiology, School of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Saul Villeda
- The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, California, USA; Department of Anatomy, University of California San Francisco, San Francisco, California, USA
| | - Stephan J Sanders
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, California, USA; Institute of Developmental and Regenerative Medicine, Department of Paediatrics, University of Oxford, Oxford OX3 7TY, United Kingdom
| | - Tippi C MacKenzie
- Department of Surgery, University of California San Francisco, San Francisco, California, USA; The Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, San Francisco, California, USA; Center for Maternal-Fetal Precision Medicine, University of California San Francisco, San Francisco, California, USA.
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Ehrke-Schulz E, Zhang W, Gao J, Ehrhardt A. Recent Advances in Preclinical Developments Using Adenovirus Hybrid Vectors. Hum Gene Ther 2018; 28:833-841. [PMID: 28854818 DOI: 10.1089/hum.2017.140] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Adenovirus (Ad)-based vectors are efficient gene-transfer vehicles to deliver foreign DNA into living organisms, offering large cargo capacity and low immunogenicity and genotoxicity. As Ad shows low integration rates of their genomes into host chromosomes, vector-derived gene expression decreases due to continuous cell cycling in regenerating tissues and dividing cell populations. To overcome this hurdle, adenoviral delivery can be combined with mechanisms leading to maintenance of therapeutic DNA and long-term effects of the desired treatment. Several hybrid Ad vectors (AdV) exploiting various strategies for long-term treatment have been developed and characterized. This review summarizes recent developments of preclinical approaches using hybrid AdVs utilizing either the Sleeping Beauty transposase system for somatic integration into host chromosomes or designer nucleases, including transcription activator-like effector nucleases and clustered regularly interspaced short palindromic repeats/CRISPR-associated protein-9 nuclease for permanent gene editing. Further options on how to optimize these vectors further are discussed, which may lead to future clinical applications of these versatile gene-therapy tools.
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Affiliation(s)
- Eric Ehrke-Schulz
- Chair for Virology and Microbiology, Center for Biomedical Education and Research (ZBAF), Department for Human Medicine, Faculty of Health, Witten/Herdecke University , Witten, Germany
| | - Wenli Zhang
- Chair for Virology and Microbiology, Center for Biomedical Education and Research (ZBAF), Department for Human Medicine, Faculty of Health, Witten/Herdecke University , Witten, Germany
| | - Jian Gao
- Chair for Virology and Microbiology, Center for Biomedical Education and Research (ZBAF), Department for Human Medicine, Faculty of Health, Witten/Herdecke University , Witten, Germany
| | - Anja Ehrhardt
- Chair for Virology and Microbiology, Center for Biomedical Education and Research (ZBAF), Department for Human Medicine, Faculty of Health, Witten/Herdecke University , Witten, Germany
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Hodge R, Narayanavari SA, Izsvák Z, Ivics Z. Wide Awake and Ready to Move: 20 Years of Non-Viral Therapeutic Genome Engineering with the Sleeping Beauty Transposon System. Hum Gene Ther 2018; 28:842-855. [PMID: 28870121 DOI: 10.1089/hum.2017.130] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Gene therapies will only become a widespread tool in the clinical treatment of human diseases with the advent of gene transfer vectors that integrate genetic information stably, safely, effectively, and economically. Two decades after the discovery of the Sleeping Beauty (SB) transposon, it has been transformed into a vector system that is fulfilling these requirements. SB may well overcome some of the limitations associated with viral gene transfer vectors and transient non-viral gene delivery approaches that are being used in the majority of ongoing clinical trials. The SB system has achieved a high level of stable gene transfer and sustained transgene expression in multiple primary human somatic cell types, representing crucial steps that may permit its clinical use in the near future. This article reviews the most important aspects of SB as a tool for gene therapy, including aspects of its vectorization and genomic integration. As an illustration, the clinical development of the SB system toward gene therapy of age-related macular degeneration and cancer immunotherapy is highlighted.
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Affiliation(s)
- Russ Hodge
- 1 Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) , Berlin, Germany
| | - Suneel A Narayanavari
- 1 Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) , Berlin, Germany
| | - Zsuzsanna Izsvák
- 1 Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) , Berlin, Germany
| | - Zoltán Ivics
- 2 Division of Medical Biotechnology, Paul Ehrlich Institute , Langen, Germany
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Chansel-Debordeaux L, Bourdenx M, Dovero S, Grouthier V, Dutheil N, Espana A, Groc L, Jimenez C, Bezard E, Dehay B. In utero delivery of rAAV2/9 induces neuronal expression of the transgene in the brain: towards new models of Parkinson’s disease. Gene Ther 2017; 24:801-809. [DOI: 10.1038/gt.2017.84] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 06/26/2017] [Accepted: 08/23/2017] [Indexed: 12/21/2022]
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Kebriaei P, Izsvák Z, Narayanavari SA, Singh H, Ivics Z. Gene Therapy with the Sleeping Beauty Transposon System. Trends Genet 2017; 33:852-870. [PMID: 28964527 DOI: 10.1016/j.tig.2017.08.008] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Revised: 08/24/2017] [Accepted: 08/31/2017] [Indexed: 11/16/2022]
Abstract
The widespread clinical implementation of gene therapy requires the ability to stably integrate genetic information through gene transfer vectors in a safe, effective, and economical manner. The latest generation of Sleeping Beauty (SB) transposon vectors fulfills these requirements, and may overcome limitations associated with viral gene transfer vectors and transient nonviral gene delivery approaches that are prevalent in ongoing clinical trials. The SB system enables high-level stable gene transfer and sustained transgene expression in multiple primary human somatic cell types, thereby representing a highly attractive gene transfer strategy for clinical use. Here, we review the most important aspects of using SB for gene therapy, including vectorization as well as genomic integration features. We also illustrate the path to successful clinical implementation by highlighting the application of chimeric antigen receptor (CAR)-modified T cells in cancer immunotherapy.
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Affiliation(s)
- Partow Kebriaei
- Department of Stem Cell Transplant and Cellular Therapy, MD Anderson Cancer Center, Houston, TX, USA
| | - Zsuzsanna Izsvák
- Mobile DNA, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Suneel A Narayanavari
- Mobile DNA, Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin, Germany
| | - Harjeet Singh
- Department of Pediatrics, MD Anderson Cancer Center, Houston, TX, USA
| | - Zoltán Ivics
- Division of Medical Biotechnology, Paul Ehrlich Institute, Langen, Germany.
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Tyler CM, Federoff HJ. CNS Gene Therapy and a Nexus of Complexity: Systems and Biology at a Crossroads. Cell Transplant 2017; 15:267-73. [PMID: 16719061 DOI: 10.3727/000000006783982007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Gene therapy is a potentially promising new treatment for neurodegenerative disorders such as Alzheimer's disease (AD), which has been difficult to treat with conventional therapeutics. Viral vector-mediated somatic gene therapy is a rapidly developing methodology for providing never before achieved capability to deliver specific genes to the CNS in a highly localized and controlled manner. With the advent and refinements of this technology one focus is directed to which genes are the most appropriate to select for specific disease indications. Nerve growth factor (NGF), a potent survival factor for critical cell populations that degenerate in AD, has been chosen already for clinical gene therapy trials in human AD patients. Much knowledge about the pathophysiological underpinnings of AD is still lacking to make clear which patients may benefit from a gene therapy approach. Moreover, a detailed understanding of sustained NGF action in the normal and diseased CNS needs to be resolved before conclusions can be drawn regarding the utility of NGF gene therapy. Systematic efforts to acquire this new knowledge should compel clinically and biologically sophisticated efforts to advance gene therapy for neurodegenerative diseases.
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Affiliation(s)
- Carolyn M Tyler
- Center for Aging and Developmental Biology, Aab Institute of Biomedical Sciences, Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester NY 14642, USA
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Hudecek M, Izsvák Z, Johnen S, Renner M, Thumann G, Ivics Z. Going non-viral: the Sleeping Beauty transposon system breaks on through to the clinical side. Crit Rev Biochem Mol Biol 2017; 52:355-380. [PMID: 28402189 DOI: 10.1080/10409238.2017.1304354] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Molecular medicine has entered a high-tech age that provides curative treatments of complex genetic diseases through genetically engineered cellular medicinal products. Their clinical implementation requires the ability to stably integrate genetic information through gene transfer vectors in a safe, effective and economically viable manner. The latest generation of Sleeping Beauty (SB) transposon vectors fulfills these requirements, and may overcome limitations associated with viral gene transfer vectors and transient non-viral gene delivery approaches that are prevalent in ongoing pre-clinical and translational research. The SB system enables high-level stable gene transfer and sustained transgene expression in multiple primary human somatic cell types, thereby representing a highly attractive gene transfer strategy for clinical use. Here we review several recent refinements of the system, including the development of optimized transposons and hyperactive SB variants, the vectorization of transposase and transposon as mRNA and DNA minicircles (MCs) to enhance performance and facilitate vector production, as well as a detailed understanding of SB's genomic integration and biosafety features. This review also provides a perspective on the regulatory framework for clinical trials of gene delivery with SB, and illustrates the path to successful clinical implementation by using, as examples, gene therapy for age-related macular degeneration (AMD) and the engineering of chimeric antigen receptor (CAR)-modified T cells in cancer immunotherapy.
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Affiliation(s)
- Michael Hudecek
- a Medizinische Klinik und Poliklinik II , Universitätsklinikum Würzburg , Würzburg , Germany
| | - Zsuzsanna Izsvák
- b Mobile DNA , Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) , Berlin , Germany
| | - Sandra Johnen
- c Department of Ophthalmology , University Hospital RWTH Aachen , Aachen , Germany
| | - Matthias Renner
- d Division of Medical Biotechnology , Paul Ehrlich Institute , Langen, Germany
| | - Gabriele Thumann
- e Département des Neurosciences Cliniques Service d'Ophthalmologie , Hôpitaux Universitaires de Genève , Genève , Switzerland
| | - Zoltán Ivics
- d Division of Medical Biotechnology , Paul Ehrlich Institute , Langen, Germany
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Narayanavari SA, Chilkunda SS, Ivics Z, Izsvák Z. Sleeping Beauty transposition: from biology to applications. Crit Rev Biochem Mol Biol 2016; 52:18-44. [PMID: 27696897 DOI: 10.1080/10409238.2016.1237935] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Sleeping Beauty (SB) is the first synthetic DNA transposon that was shown to be active in a wide variety of species. Here, we review studies from the last two decades addressing both basic biology and applications of this transposon. We discuss how host-transposon interaction modulates transposition at different steps of the transposition reaction. We also discuss how the transposon was translated for gene delivery and gene discovery purposes. We critically review the system in clinical, pre-clinical and non-clinical settings as a non-viral gene delivery tool in comparison with viral technologies. We also discuss emerging SB-based hybrid vectors aimed at combining the attractive safety features of the transposon with effective viral delivery. The success of the SB-based technology can be fundamentally attributed to being able to insert fairly randomly into genomic regions that allow stable long-term expression of the delivered transgene cassette. SB has emerged as an efficient and economical toolkit for safe and efficient gene delivery for medical applications.
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Affiliation(s)
- Suneel A Narayanavari
- a Mobile DNA , Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) , Berlin , Germany
| | - Shreevathsa S Chilkunda
- a Mobile DNA , Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) , Berlin , Germany
| | - Zoltán Ivics
- b Division of Medical Biotechnology , Paul Ehrlich Institute , Langen , Germany
| | - Zsuzsanna Izsvák
- a Mobile DNA , Max Delbrück Center for Molecular Medicine in the Helmholtz Association (MDC) , Berlin , Germany
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Turunen TAK, Laakkonen JP, Alasaarela L, Airenne KJ, Ylä-Herttuala S. Sleeping Beauty-baculovirus hybrid vectors for long-term gene expression in the eye. J Gene Med 2014; 16:40-53. [PMID: 24464652 DOI: 10.1002/jgm.2756] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2013] [Revised: 11/18/2013] [Accepted: 01/22/2014] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND A baculovirus vector is capable of efficiently transducing many nondiving and diving cell types. However, the potential of baculovirus is restricted for many gene delivery applications as a result of the transient gene expression that it mediates. The plasmid-based Sleeping Beauty (SB) transposon system integrates transgenes into target cell genome efficiently with a genomic integration pattern that is generally considered safer than the integration of many other integrating vectors; yet efficient delivery of therapeutic genes into cells of target tissues in vivo is a major challenge for nonviral gene therapy. In the present study, SB was introduced into baculovirus to obtain novel hybrid vectors that would combine the best features of the two vector systems (i.e. effective gene delivery and efficient integration into the genome), thus circumventing the major limitations of these vectors. METHODS We constructed and optimized SB-baculovirus hybrid vectors that bear either SB100x transposase or SB transposon in the forward or reverse orientations with respect to the viral backbone The functionality of the novel hybrid vectors was investigated in cell cultures and in a proof-of-concept study in the mouse eye. RESULTS The hybrid vectors showed high and sustained transgene expression that remained stable and demonstrated no signs of decline during the 2 months follow-up in vitro. These results were verified in the mouse eye where persistent transgene expression was detected two months after intravitreal injection. CONCLUSIONS Our results confirm that (i) SB-baculovirus hybrid vectors mediate long-term gene expression in vitro and in vivo, and (ii) the hybrid vectors are potential new tools for the treatment of ocular diseases.
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Affiliation(s)
- Tytteli Anni Kaarina Turunen
- A. I. Virtanen Institute for Molecular Sciences, Department of Biotechnology and Molecular Medicine, University of Eastern Finland, Kuopio, Finland
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Skipper KA, Andersen PR, Sharma N, Mikkelsen JG. DNA transposon-based gene vehicles - scenes from an evolutionary drive. J Biomed Sci 2013; 20:92. [PMID: 24320156 PMCID: PMC3878927 DOI: 10.1186/1423-0127-20-92] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 11/27/2013] [Indexed: 12/12/2022] Open
Abstract
DNA transposons are primitive genetic elements which have colonized living organisms from plants to bacteria and mammals. Through evolution such parasitic elements have shaped their host genomes by replicating and relocating between chromosomal loci in processes catalyzed by the transposase proteins encoded by the elements themselves. DNA transposable elements are constantly adapting to life in the genome, and self-suppressive regulation as well as defensive host mechanisms may assist in buffering ‘cut-and-paste’ DNA mobilization until accumulating mutations will eventually restrict events of transposition. With the reconstructed Sleeping Beauty DNA transposon as a powerful engine, a growing list of transposable elements with activity in human cells have moved into biomedical experimentation and preclinical therapy as versatile vehicles for delivery and genomic insertion of transgenes. In this review, we aim to link the mechanisms that drive transposon evolution with the realities and potential challenges we are facing when adapting DNA transposons for gene transfer. We argue that DNA transposon-derived vectors may carry inherent, and potentially limiting, traits of their mother elements. By understanding in detail the evolutionary journey of transposons, from host colonization to element multiplication and inactivation, we may better exploit the potential of distinct transposable elements. Hence, parallel efforts to investigate and develop distinct, but potent, transposon-based vector systems will benefit the broad applications of gene transfer. Insight and clever optimization have shaped new DNA transposon vectors, which recently debuted in the first DNA transposon-based clinical trial. Learning from an evolutionary drive may help us create gene vehicles that are safer, more efficient, and less prone for suppression and inactivation.
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Affiliation(s)
| | | | | | - Jacob Giehm Mikkelsen
- Department of Biomedicine, Aarhus University, Wilh, Meyers Allé 4, DK-8000, Aarhus C, Denmark.
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Cai Y, Bak RO, Krogh LB, Staunstrup NH, Moldt B, Corydon TJ, Schrøder LD, Mikkelsen JG. DNA transposition by protein transduction of the piggyBac transposase from lentiviral Gag precursors. Nucleic Acids Res 2013; 42:e28. [PMID: 24270790 PMCID: PMC3936723 DOI: 10.1093/nar/gkt1163] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
DNA transposon-based vectors have emerged as gene vehicles with a wide biomedical and therapeutic potential. So far, genomic insertion of such vectors has relied on the co-delivery of genetic material encoding the gene-inserting transposase protein, raising concerns related to persistent expression, insertional mutagenesis and cytotoxicity. This report describes potent DNA transposition achieved by direct delivery of transposase protein. By adapting integrase-deficient lentiviral particles (LPs) as carriers of the hyperactive piggyBac transposase protein (hyPBase), we demonstrate rates of DNA transposition that are comparable with the efficiency of a conventional plasmid-based strategy. Embedded in the Gag polypeptide, hyPBase is robustly incorporated into LPs and liberated from the viral proteins by the viral protease during particle maturation. We demonstrate lentiviral co-delivery of the transposase protein and vector RNA carrying the transposon sequence, allowing robust DNA transposition in a variety of cell types. Importantly, this novel delivery method facilitates a balanced cellular uptake of hyPBase, as shown by confocal microscopy, and allows high-efficiency production of clones harboring a single transposon insertion. Our findings establish engineered LPs as a new tool for transposase delivery. We believe that protein transduction methods will increase applicability and safety of DNA transposon-based vector technologies.
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Affiliation(s)
- Yujia Cai
- Department of Biomedicine, Aarhus University, DK-8000 Aarhus C, Denmark and Department of Immunology and Microbial Science and IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, CA 92037, USA
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12
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Huang S, Kamihira M. Development of hybrid viral vectors for gene therapy. Biotechnol Adv 2013; 31:208-23. [DOI: 10.1016/j.biotechadv.2012.10.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 09/26/2012] [Accepted: 10/04/2012] [Indexed: 01/23/2023]
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Di Matteo M, Belay E, Chuah MK, Vandendriessche T. Recent developments in transposon-mediated gene therapy. Expert Opin Biol Ther 2012; 12:841-58. [PMID: 22679910 DOI: 10.1517/14712598.2012.684875] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
INTRODUCTION The continuous improvement of gene transfer technologies has broad implications for stem cell biology, gene discovery, and gene therapy. Although viral vectors are efficient gene delivery vehicles, their safety, immunogenicity and manufacturing challenges hamper clinical progress. In contrast, non-viral gene delivery systems are less immunogenic and easier to manufacture. AREAS COVERED In this review, we explore the emerging potential of transposons in gene and cell therapy. The safety, efficiency, and biology of novel hyperactive Sleeping Beauty (SB) and piggyBac (PB) transposon systems will be highlighted for ex vivo gene therapy in clinically relevant adult stem/progenitor cells, particularly hematopoietic stem cells (HSCs), mesenchymal stem cells (MSCs), myoblasts, and induced pluripotent stem (iPS) cells. Moreover, efforts toward in vivo transposon-based gene therapy will be discussed. EXPERT OPINION The latest generation SB and PB transposons currently represent some of the most attractive systems for stable non-viral genetic modification of primary cells, particularly adult stem cells. This paves the way toward the use of transposons as a non-viral gene therapy approach to correct hereditary disorders including those that affect the hematopoietic system. The development of targeted integration into "safe harbor" genetic loci may further improve their safety profile.
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Affiliation(s)
- Mario Di Matteo
- Free University of Brussels, Division of Gene Therapy & Regenerative Medicine, Laarbeeklaan 103, B-1090 Brussels, Belgium
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Abstract
The relative inaccessibility of the brain compared with other major organs, the highly regulated transfer of molecules across the blood-brain barrier and the limited capacity of neurons to regenerate, make efficient gene delivery to the CNS both challenging and imperative. Perinatal gene delivery to the CNS represents a powerful tool for the investigation of genes in development and disease. However, it may also hold immense therapeutic value for neonatal lethal neurodegenerative diseases for which no treatment is available. This article will focus on the use of perinatal gene delivery as a research tool and the potential it has to develop into a realistic therapy that can be translated to the clinic.
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Ivics Z, Izsvák Z. Nonviral gene delivery with the sleeping beauty transposon system. Hum Gene Ther 2012; 22:1043-51. [PMID: 21867398 DOI: 10.1089/hum.2011.143] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Effective gene therapy requires robust delivery of therapeutic genes into relevant target cells, long-term gene expression, and minimal risks of secondary effects. Nonviral gene transfer approaches typically result in only short-lived transgene expression in primary cells, because of the lack of nuclear maintenance of the vector over several rounds of cell division. The development of efficient and safe nonviral vectors armed with an integrating feature would thus greatly facilitate clinical gene therapy studies. The latest generation transposon technology based on the Sleeping Beauty (SB) transposon may potentially overcome some of these limitations. SB was shown to provide efficient stable gene transfer and sustained transgene expression in primary cell types, including human hematopoietic progenitors, mesenchymal stem cells, muscle stem/progenitor cells (myoblasts), induced pluripotent stem cells, and T cells. These cells are relevant targets for stem cell biology, regenerative medicine, and gene- and cell-based therapies of complex genetic diseases. Moreover, the first-in-human clinical trial has been launched to use redirected T cells engineered with SB for gene therapy of B cell lymphoma. We discuss aspects of cellular delivery of the SB transposon system, transgene expression provided by integrated transposon vectors, target site selection of the transposon vectors, and potential risks associated with random genomic insertion.
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Affiliation(s)
- Zoltán Ivics
- Max Delbrück Center for Molecular Medicine, Berlin 13125, Germany.
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Nedelkovska H, Robert J. Optimized transgenesis in Xenopus laevis/gilli isogenetic clones for immunological studies. Genesis 2011; 50:300-6. [PMID: 21954010 DOI: 10.1002/dvg.20809] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 09/16/2011] [Accepted: 09/18/2011] [Indexed: 11/11/2022]
Abstract
Xenopus laevis provides a unique animal model, alternative to mouse, to study immunology. Even though, several methodologies have been developed for the generation of transgenic Xenopus, to date none have been adapted for the X. laevis/gilli (LG) isogenetic clones that are essential for immunological studies. Since LG clones are generated via gynogenesis, transgenic methods using transgene integration into the sperm nuclei are not suited. Therefore, we have tested three alternative methods for LG transgenesis: the phiC31 integrase, the Sleeping Beauty transposase, and the I-SceI meganuclease. All three techniques produced transgenic LG clones; however, the I-SceI meganuclease was most effective. It resulted in high transgenesis efficiency (35-50%), bright nonmosaic GFP expression as well as stable germline transmission with 100% of the progeny carrying the transgene. Production of transgenic LG clones will allow us to modulate immune gene expression and further strengthen X. laevis as a biomedical model.
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Affiliation(s)
- Hristina Nedelkovska
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14642, USA
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17
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Jerusalinsky D, Baez MV, Epstein AL. Herpes simplex virus type 1-based amplicon vectors for fundamental research in neurosciences and gene therapy of neurological diseases. ACTA ACUST UNITED AC 2011; 106:2-11. [PMID: 22108428 DOI: 10.1016/j.jphysparis.2011.11.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Revised: 10/11/2011] [Accepted: 11/04/2011] [Indexed: 12/24/2022]
Abstract
Somatic manipulation of the nervous system without the involvement of the germinal line appears as a powerful counterpart of the transgenic strategy. The use of viral vectors to produce specific, transient and localized knockout, knockdown, ectopic expression or overexpression of a gene, leads to the possibility of analyzing both in vitro and in vivo molecular basis of neural function. In this approach, viral particles engineered to carry transgenic sequences are delivered into discrete brain regions, to transduce cells that will express the transgenic products. Amplicons are replication-incompetent helper-dependent vectors derived from herpes simplex virus type 1 (HSV-1), with several advantages that potentiate their use in neurosciences: (1) minimal toxicity: amplicons do not encode any virus proteins, are neither toxic for the infected cells nor pathogenic for the inoculated animals and elicit low levels of adaptive immune responses; (2) extensive transgene capacity to carry up to 150-kb of foreign DNA; i.e., entire genes with regulatory sequences could be delivered; (3) widespread cellular tropism: amplicons can experimentally infect several cell types including glial cells, though naturally the virus infects mainly neurons and epithelial cells; (4) since the viral genome does not integrate into cellular chromosomes there is low probability to induce insertional mutagenesis. Recent investigations on gene transfer into the brain using these vectors, have focused on gene therapy of inherited genetic diseases affecting the nervous system, such as ataxias, or on neurodegenerative disorders using experimental models of Parkinson's or Alzheimer's disease. Another group of studies used amplicons to investigate complex neural functions such as neuroplasticity, anxiety, learning and memory. In this short review, we summarize recent data supporting the potential of HSV-1 based amplicon vector model for gene delivery and modulation of gene expression in primary cultures of neuronal cells and into the brain of living animals.
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Affiliation(s)
- Diana Jerusalinsky
- Instituto de Biología Celular y Neurociencia (IBCN), CONICET-UBA. Buenos Aires, Argentina.
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18
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Development of the hybrid Sleeping Beauty-baculovirus vector for sustained gene expression and cancer therapy. Gene Ther 2011; 19:844-51. [DOI: 10.1038/gt.2011.129] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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19
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Comparison of piggyBac transposition efficiency between linear and circular donor vectors in mammalian cells. J Biotechnol 2011; 154:205-8. [DOI: 10.1016/j.jbiotec.2011.05.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2011] [Revised: 05/06/2011] [Accepted: 05/19/2011] [Indexed: 11/19/2022]
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20
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Szebényi K, Erdei Z, Péntek A, Sebe A, Orbán TI, Sarkadi B, Apáti Á. Human pluripotent stem cells in pharmacological and toxicological screening: new perspectives for personalized medicine. Per Med 2011; 8:347-364. [DOI: 10.2217/pme.11.19] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Human stem cells provide an important novel tool for generating in vitro pharmacological and toxicological test systems. In the development of new targeted therapies, as well as in critical safety issues, including hepato-, neuro- and cardio-toxicity, animal-based tests are mostly unsatisfactory, whereas the use of in vitro model systems is limited by the unavailability of relevant human tissues. Human embryonic stem cell lines may fill this gap and offer an advantage over primary cultures as well as tissue-derived (adult) stem cells. Human embryonic stem cells represent an unlimited source for the production of differentiated somatic progenies and allow various stable genetic manipulations. As a new opening in personalized medicine test systems, the generation of induced pluripotent stem cell lines and their derivatives can provide patient- and disease-specific cellular assays for drug development and safety assessments. This article reviews promising human stem cell applications in pharmacological and toxicological screenings, focusing on the implications for personalized medicine.
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Affiliation(s)
- Kornélia Szebényi
- Membrane Research Group, Hungarian Academy of Sciences & National Blood Center, 1113 Budapest, Diószegi u. 64, Hungary
| | - Zsuzsa Erdei
- Membrane Research Group, Hungarian Academy of Sciences & National Blood Center, 1113 Budapest, Diószegi u. 64, Hungary
| | - Adrienn Péntek
- Membrane Research Group, Hungarian Academy of Sciences & National Blood Center, 1113 Budapest, Diószegi u. 64, Hungary
| | - Attila Sebe
- Membrane Research Group, Hungarian Academy of Sciences & National Blood Center, 1113 Budapest, Diószegi u. 64, Hungary
- Department of Biochemistry & Molecular Biology, Medical & Health Science Center, University of Debrecen, Debrecen, Hungary
| | - Tamás I Orbán
- Membrane Research Group, Hungarian Academy of Sciences & National Blood Center, 1113 Budapest, Diószegi u. 64, Hungary
| | - Balázs Sarkadi
- Membrane Research Group, Hungarian Academy of Sciences & National Blood Center, 1113 Budapest, Diószegi u. 64, Hungary
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21
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Moldt B, Miskey C, Staunstrup NH, Gogol-Döring A, Bak RO, Sharma N, Mátés L, Izsvák Z, Chen W, Ivics Z, Mikkelsen JG. Comparative genomic integration profiling of Sleeping Beauty transposons mobilized with high efficacy from integrase-defective lentiviral vectors in primary human cells. Mol Ther 2011; 19:1499-510. [PMID: 21468003 DOI: 10.1038/mt.2011.47] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
It has been previously shown that integrase-defective HIV-1-based gene vectors can serve, with moderate efficiency, as substrate for DNA transposition by a transiently expressed Sleeping Beauty (SB) transposase. Here, we describe the enhanced gene transfer properties of a HIV-1/SB hybrid vector that allows efficient DNA transposition, facilitated by the hyperactive SB100X transposase, from vector DNA intermediates in primary human cells. Potent transposase-dependent integration of genetic cargo carried by the hybrid HIV-1/SB vector (up to 160-fold above background) is reported in human cell lines as well as in primary human fibroblasts and keratinocytes. The efficiency of transgene integration in context of the newly developed hybrid vector is comparable with that of conventional lentiviral vectors (LVs). Integration profiles of integrating HIV-1-derived vectors and SB transposons mobilized from LVs are investigated by deep sequencing of a large number of integration sites. A significant bias of lentiviral integrations in genes is reported, confirming that biological properties of the viral integration machinery facilitate preferred insertion into actively transcribed genomic regions. In sharp contrast, lentiviral insertions catalyzed by the SB100X transposase are far more random with respect to genes. Based on these properties, HIV-1/SB vectors may become valuable tools for genetic engineering and therapeutic gene transfer.
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Affiliation(s)
- Brian Moldt
- Department of Human Genetics, University of Aarhus, Aarhus, Denmark
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22
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Abstract
The cellular and molecular environment present in the fetus and early newborn provides an excellent opportunity for effective gene transfer. Innate and pre-existing anti-vector immunity may be attenuated or absent and the adaptive immune system predisposed to tolerance towards xenoproteins. Stem cell and progenitor cell populations are abundant, active and accessible. In addition, for treatment of early lethal genetic diseases of the nervous system, the overarching advantage may be that early gene supplementation prevents the onset of irreversible pathological changes. Gene transfer to the fetal mouse nervous system was achieved, albeit inefficiently, as far back as the mid-1980s. Recently, improvements in vector design and production have culminated in near-complete correction of a mouse model of spinal muscular atrophy. In the present article, we review perinatal gene transfer from both a therapeutic and technological perspective.
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Azadniv M, Bowers WJ, Topham DJ, Crispe IN. CD4+ T cell effects on CD8+ T cell location defined using bioluminescence. PLoS One 2011; 6:e16222. [PMID: 21283759 PMCID: PMC3024405 DOI: 10.1371/journal.pone.0016222] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 12/16/2010] [Indexed: 02/07/2023] Open
Abstract
T lymphocytes of the CD8+ class are critical in delivering cytotoxic function and in controlling viral and intracellular infections. These cells are “helped” by T lymphocytes of the CD4+ class, which facilitate their activation, clonal expansion, full differentiation and the persistence of memory. In this study we investigated the impact of CD4+ T cells on the location of CD8+ T cells, using antibody-mediated CD4+ T cell depletion and imaging the antigen-driven redistribution of bioluminescent CD8+ T cells in living mice. We documented that CD4+ T cells influence the biodistribution of CD8+ T cells, favoring their localization to abdominal lymph nodes. Flow cytometric analysis revealed that this was associated with an increase in the expression of specific integrins. The presence of CD4+ T cells at the time of initial CD8+ T cell activation also influences their biodistribution in the memory phase. Based on these results, we propose the model that one of the functions of CD4+ T cell “help” is to program the homing potential of CD8+ T cells.
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Affiliation(s)
- Mitra Azadniv
- David H. Smith Center for Microbiology and Immunology, Aab Institute for Biomedical Research, University of Rochester Medical Center, Rochester, New York, United States of America
| | - William J. Bowers
- Department of Neurology, Center for Aging and Developmental Biology, Aab Institute for Biomedical Research, University of Rochester Medical Center, Rochester, New York, United States of America
| | - David J. Topham
- David H. Smith Center for Microbiology and Immunology, Aab Institute for Biomedical Research, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Ian N. Crispe
- Seattle Biomedical Research Institute, Seattle, Washington, United States of America
- * E-mail:
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Izsvák Z, Hackett PB, Cooper LJN, Ivics Z. Translating Sleeping Beauty transposition into cellular therapies: victories and challenges. Bioessays 2010; 32:756-67. [PMID: 20652893 DOI: 10.1002/bies.201000027] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Recent results confirm that long-term expression of therapeutic transgenes can be achieved by using a transposon-based system in primary stem cells and in vivo. Transposable elements are natural DNA transfer vehicles that are capable of efficient genomic insertion. The latest generation, Sleeping Beauty transposon-based hyperactive vector (SB100X), is able to address the basic problem of non-viral approaches - that is, low efficiency of stable gene transfer. The combination of transposon-based non-viral gene transfer with the latest improvements of non-viral delivery techniques could provide a long-term therapeutic effect without compromising biosafety. The new challenges of pre-clinical research will focus on further refinement of the technology in large animal models and improving the safety profile of SB vectors by target-selected transgene integration into genomic "safe harbors." The first clinical application of the SB system will help to validate the safety of this approach.
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Affiliation(s)
- Zsuzsanna Izsvák
- Max-Delbrück Center for Molecular Medicine (MDC), Berlin, Germany.
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25
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de Silva S, Mastrangelo MA, Lotta LT, Burris CA, Izsvák Z, Ivics Z, Bowers WJ. Herpes simplex virus/Sleeping Beauty vector-based embryonic gene transfer using the HSB5 mutant: loss of apparent transposition hyperactivity in vivo. Hum Gene Ther 2010; 21:1603-13. [PMID: 20507234 DOI: 10.1089/hum.2010.062] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The Sleeping Beauty (SB) transposon system has been successfully used as a gene delivery tool in nonviral and viral vector platforms. Since its initial reconstruction, a series of hyperactive mutants of SB have been generated. Questions remain as to whether the enhanced in vitro activities of these SB transposase mutants translate to the in vivo setting, and whether such increased integration efficiencies will ultimately compromise the safety profile of the transposon platform by raising the risk of genomic insertional mutagenesis. Herein, we compared the in vivo impact of a herpes simplex virus (HSV) amplicon-vectored "wild-type" SB transposase (SB10) and a "hyperactive" SB mutant (HSB5), codelivered in utero with the HSVT-βgeo transposable reporter amplicon vector to embryonic day 14.5 C57BL/6 mice. The SB10 and HSB5 transposases do not disparately affect the viability and development of injected mouse embryos. Quantitation of brain-resident βgeo expression on postnatal day 21 revealed that mice receiving HSB5 exhibited only a trending increase in transgene expression compared with the SB10-infused group, an outcome that did not mirror the marked enhancement of HSB5-mediated transposition observed in vitro. These findings indicate that in vivo application of hyperactive SB mutants, although not differentially genotoxic to the developing mouse embryo, does not necessarily provide a significant therapeutic advantage over the employment of a lesser active SB when delivered in the context of the HSV/SB amplicon platform.
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Affiliation(s)
- Suresh de Silva
- Center for Neural Development and Disease, University of Rochester Medical Center, Rochester, NY 14642, USA
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26
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de Silva S, Lotta LT, Burris CA, Bowers WJ. Virion-associated cofactor high-mobility group DNA-binding protein-1 facilitates transposition from the herpes simplex virus/Sleeping Beauty amplicon vector platform. Hum Gene Ther 2010; 21:1615-22. [PMID: 20568967 DOI: 10.1089/hum.2010.022] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The development of the integration-competent, herpes simplex virus/Sleeping Beauty (HSV/SB) amplicon vector platform has created a means to efficiently and stably deliver therapeutic transcription units (termed "transgenons") to neurons within the mammalian brain. Furthermore, an investigation into the transposition capacity of the HSV/SB vector system revealed that the amplicon genome provides an optimal substrate for the transposition of transgenons at least 12 kb in length [de Silva, S., Mastrangelo, M.A., Lotta, L.T., Jr., Burris, C.A., Federoff, H.J., and Bowers, W.J. ( 2010 ). Gene Ther. 17, 424-431]. These results prompted an investigation into the factors that may contribute toward efficient transposition from the HSV/SB amplicon. One of the cellular cofactors known to play a key role during SB-mediated transposition is the high-mobility group DNA-binding protein-1 (HMGB1). Our present investigation into the role of HMGB1 during amplicon-based transposition revealed that transposition is not strictly dependent on the presence of cellular HMGB1, contrary to what had been previously demonstrated with plasmid-based SB transposition. We have shown for the first time that during amplicon preparation, biologically active HMGB1 derived from the packaging cell line is copackaged into amplicon vector particles. As a result, HSV/SB amplicon virions arrive prearmed with HMGB1 protein at levels sufficient for facilitating SB-mediated transposition in the transduced mammalian cell.
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Affiliation(s)
- Suresh de Silva
- Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
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27
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de Oliveira AP, Fraefel C. Herpes simplex virus type 1/adeno-associated virus hybrid vectors. Open Virol J 2010; 4:109-22. [PMID: 20811580 PMCID: PMC2930156 DOI: 10.2174/1874357901004030109] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2009] [Revised: 01/12/2010] [Accepted: 01/13/2010] [Indexed: 11/22/2022] Open
Abstract
Herpes simplex virus type 1 (HSV-1) amplicons can accommodate foreign DNA of any size up to 150 kbp and, therefore, allow extensive combinations of genetic elements. Genomic sequences as well as cDNA, large transcriptional regulatory sequences for cell type-specific expression, multiple transgenes, and genetic elements from other viruses to create hybrid vectors may be inserted in a modular fashion. Hybrid amplicons use genetic elements from HSV-1 that allow replication and packaging of the vector DNA into HSV-1 virions, and genetic elements from other viruses that either direct integration of transgene sequences into the host genome or allow episomal maintenance of the vector. Thus, the advantages of the HSV-1 amplicon system, including large transgene capacity, broad host range, strong nuclear localization, and availability of helper virus-free packaging systems are retained and combined with those of heterologous viral elements that confer genetic stability to the vector DNA. Adeno-associated virus (AAV) has the unique capability of integrating its genome into a specific site, designated AAVS1, on human chromosome 19. The AAV rep gene and the inverted terminal repeats (ITRs) that flank the AAV genome are sufficient for this process. HSV-1 amplicons have thus been designed that contain the rep gene and a transgene cassette flanked by AAV ITRs. These HSV/AAV hybrid vectors direct site-specific integration of transgene sequences into AAVS1 and support long-term transgene expression.
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Affiliation(s)
| | - Cornel Fraefel
- Institute of Virology, University of Zurich, Zurich, Switzerland
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28
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Hackett PB, Largaespada DA, Cooper LJN. A transposon and transposase system for human application. Mol Ther 2010; 18:674-83. [PMID: 20104209 PMCID: PMC2862530 DOI: 10.1038/mt.2010.2] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2009] [Accepted: 01/04/2010] [Indexed: 12/12/2022] Open
Abstract
The stable introduction of therapeutic transgenes into human cells can be accomplished using viral and nonviral approaches. Transduction with clinical-grade recombinant viruses offers the potential of efficient gene transfer into primary cells and has a record of therapeutic successes. However, widespread application for gene therapy using viruses can be limited by their initially high cost of manufacture at a limited number of production facilities as well as a propensity for nonrandom patterns of integration. The ex vivo application of transposon-mediated gene transfer now offers an alternative to the use of viral vectors. Clinical-grade DNA plasmids can be prepared at much reduced cost and with lower immunogenicity, and the integration efficiency can be improved by the transient coexpression of a hyperactive transposase. This has facilitated the design of human trials using the Sleeping Beauty (SB) transposon system to introduce a chimeric antigen receptor (CAR) to redirect the specificity of human T cells. This review examines the rationale and safety implications of application of the SB system to genetically modify T cells to be manufactured in compliance with current good manufacturing practice (cGMP) for phase I/II trials.
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Affiliation(s)
- Perry B Hackett
- Department of Genetics, Cell Biology, and Development, Center for Genome Engineering, Institute of Human Genetics, Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota, USA
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Abstract
Transposons are promising systems for somatic gene integration because they can not only integrate exogenous genes efficiently, but also be delivered to a variety of organs using a range of transfection methods. piggyBac (PB) transposon has a high transposability in mammalian cells in vitro, and has been used for genetic and preclinical studies. However, the transposability of PB in mammalian somatic cells in vivo has not been demonstrated yet. Here, we demonstrated PB-mediated sustained gene expression in adult mice. We constructed PB-based plasmid DNA (pDNA) containing reporter [firefly and Gaussia luciferase (Gluc)] genes. Mice were transfected by injection of these pDNAs using a hydrodynamics-based procedure, and the conditions for high-level sustained gene expression were examined. Consequently, gene expressions were sustained over 2 months. Our results suggest that PB is useful for organ-selective somatic integration and sustained gene expression in mammals, and will contribute to basic genetic studies and gene therapies.
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30
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NAKANISHI H, HIGUCHI Y, KAWAKAMI S, YAMASHITA F, HASHIDA M. Development and Therapeutic Application of Transposon-based Vectors. YAKUGAKU ZASSHI 2009; 129:1433-43. [DOI: 10.1248/yakushi.129.1433] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Hideyuki NAKANISHI
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Yuriko HIGUCHI
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Shigeru KAWAKAMI
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Fumiyoshi YAMASHITA
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Mitsuru HASHIDA
- Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University
- Institute for Integrated Cell-Material Sciences, Kyoto University (iCeMS)
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31
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Müther N, Noske N, Ehrhardt A. Viral hybrid vectors for somatic integration - are they the better solution? Viruses 2009; 1:1295-324. [PMID: 21994594 PMCID: PMC3185507 DOI: 10.3390/v1031295] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2009] [Revised: 12/04/2009] [Accepted: 12/10/2009] [Indexed: 12/18/2022] Open
Abstract
The turbulent history of clinical trials in viral gene therapy has taught us important lessons about vector design and safety issues. Much effort was spent on analyzing genotoxicity after somatic integration of therapeutic DNA into the host genome. Based on these findings major improvements in vector design including the development of viral hybrid vectors for somatic integration have been achieved. This review provides a state-of-the-art overview of available hybrid vectors utilizing viruses for high transduction efficiencies in concert with various integration machineries for random and targeted integration patterns. It discusses advantages but also limitations of each vector system.
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Affiliation(s)
- Nadine Müther
- Max von Pettenkofer-Institut, Department of Virology, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 9A, 80336 Munich, Germany
| | - Nadja Noske
- Max von Pettenkofer-Institut, Department of Virology, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 9A, 80336 Munich, Germany
| | - Anja Ehrhardt
- Max von Pettenkofer-Institut, Department of Virology, Ludwig-Maximilians-Universität Munich, Pettenkoferstr. 9A, 80336 Munich, Germany
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32
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Abstract
Since its emergence onto the gene therapy scene nearly 25 years ago, the replication-defective Herpes Simplex Virus Type-1 (HSV-1) amplicon has gained significance as a versatile gene transfer platform due to its extensive transgene capacity, widespread cellular tropism, minimal immunogenicity, and its amenability to genetic manipulation. Herein, we detail the recent advances made with respect to the design of the HSV amplicon, its numerous in vitro and in vivo applications, and the current impediments this virus-based gene transfer platform faces as it navigates a challenging path towards future clinical testing.
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33
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de Silva S, Mastrangelo MA, Lotta LT, Burris CA, Federoff HJ, Bowers WJ. Extending the transposable payload limit of Sleeping Beauty (SB) using the Herpes Simplex Virus (HSV)/SB amplicon-vector platform. Gene Ther 2009; 17:424-31. [PMID: 19865178 DOI: 10.1038/gt.2009.144] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The ability of a viral vector to safely deliver and stably integrate large transgene units (transgenons), which not only include one or several therapeutic genes, but also requisite native transcriptional regulatory elements, would be of significant benefit for diseases presently refractory to available technologies. The herpes simplex virus type-1 (HSV-1) amplicon vector has the largest known payload capacity of approximately 130 kb, but its episomal maintenance within the transduced cell nucleus and induction of host cell silencing mechanisms limits the duration of the delivered therapeutic gene(s). Our laboratory developed an integration-competent version of the HSV-1 amplicon by adaptation of the Sleeping Beauty (SB) transposon system, which significantly extends transgene expression in vivo. The maximum size limit of the amplicon-vectored transposable element remains unknown, but previously published plasmid-centric studies have established that DNA segments longer than 6-kb are inefficiently transposed. Here, we compared the transposition efficiency of SB transposase in the context of both the HSV amplicon vector as well as the HSV amplicon plasmid harboring 7 and 12-kb transposable reporter transgene units. Our results indicate that the transposition efficiency of the 12-kb transposable unit via SB transposase was significantly reduced as compared with the 7-kb transposable unit when the plasmid version of the HSV amplicon was used. However, the packaged HSV amplicon vector form provided a more amenable platform from which the 12-kb transposable unit was mobilized at efficiency similar to that of the 7-kb transposable unit via the SB transposase. Overall, our results indicate that SB is competent in stably integrating transgenon units of at least 12 kb in size within the human genome upon delivery of the platform via HSV amplicons.
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Affiliation(s)
- S de Silva
- Department of Biochemistry, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
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34
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Epstein AL. HSV-1-derived amplicon vectors: recent technological improvements and remaining difficulties--a review. Mem Inst Oswaldo Cruz 2009; 104:399-410. [PMID: 19547864 DOI: 10.1590/s0074-02762009000300002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2009] [Accepted: 05/15/2009] [Indexed: 01/04/2023] Open
Abstract
Amplicons are defective and non-integrative vectors derived from herpes simplex virus type 1. As the vector genome carries no virus genes, amplicons are both non-toxic for the infected cells and non-pathogenic for the inoculated organisms. In addition, the large transgenic capacity of amplicons, which allow delivery of up to 150 Kbp of foreign DNA, makes these vectors one of the most powerful, interesting and versatile gene delivery platforms. We present here recent technological developments that have significantly improved and extended the use of amplicons, both in cultured cells and in living organisms. In addition, this review also discusses the many difficulties still pending to be solved, in order to achieve stable and physiologically regulated transgene expression.
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Affiliation(s)
- Alberto Luis Epstein
- Centre de Génétique Moléculaire et Cellulaire, Université Claude Bernard Lyon 1, Université de Lyon, Villeurbanne, France.
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35
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Progress and prospects: biological properties and technological advances of herpes simplex virus type 1-based amplicon vectors. Gene Ther 2009; 16:709-15. [PMID: 19369969 DOI: 10.1038/gt.2009.42] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The last two years have seen significant advances in our understanding of the cellular innate responses elicited or activated by the entry of amplicon particles, which may, in part, explain the transient nature of transgene expression often observed in cells infected with helper-free amplicon stocks. At the technological level, the most consistent progress has been in strategies to enhance the stability of transgene cassettes, either through integration into host chromosomes or through the conversion of the amplicon genome into a replication-competent extrachromosomal element.
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Suzuki M, Kasai K, Ohtsuki A, Godlewski J, Nowicki MO, Chiocca EA, Saeki Y. ICP0 inhibits the decrease of HSV amplicon-mediated transgene expression. Mol Ther 2009; 17:707-15. [PMID: 19223864 DOI: 10.1038/mt.2008.306] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The herpes simplex virus (HSV) amplicon vector produces an initial host response that limits transgene expression. In this study, we hypothesized that restoration of the HSV gene infected cell protein (ICP0) into the amplicon could circumvent this host response and thus overcome silencing of encoded transgenes. To test this, we constructed an amplicon vector that encodes the ICP0 under control of its native promoter (ICP0+ amplicon). Expression of ICP0 was transient and, at a multiplicity of infection (MOI) of 1, did not significantly alter interferon (IFN)-based responses against the vector or cell kinetics/apoptosis of infected cells. Chromatin immunoprecipitation (ChIP) PCR analysis revealed that conventional amplicon DNA became associated with histone deacetylase 1 (HDAC1) immediately after infection, whereas ICP0+ amplicon DNA remained relatively unbound by HDAC1 for at least 72 hours after infection. Mice administered systemic ICP0+ amplicon exhibited significantly greater and more sustained transgene expression in their livers than did those receiving conventional amplicon, likely due to increased transcriptional or post-transcriptional activity rather than increased copy numbers of vector DNA. These findings indicate that restoration of ICP0 expression may be employed within HSV amplicon constructs to decrease transgene silencing in vitro and in vivo.
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Affiliation(s)
- Masataka Suzuki
- Dardinger Laboratory for Neuro-oncology and Neurosciences, Department of Neurological Surgery, James Comprehensive Cancer Center and The Ohio State University Medical Center, Columbus, Ohio 43210, USA
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Ohlfest JR, Ivics Z, Izsvák Z. Transposable elements as plasmid-based vectors for long-term gene transfer into tumors. Methods Mol Biol 2009; 542:105-116. [PMID: 19565898 DOI: 10.1007/978-1-59745-561-9_5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A primary limitation to using nonviral vectors for cancer gene therapy is transient expression of the therapeutic gene. Even when the ultimate goal is tumor cell death, a minimum threshold of gene expression is required to kill tumor cells by direct or indirect mechanisms. It has been shown that transposable elements can significantly enhance the duration of gene expression when plasmid DNA vectors are used to transfect tumor or tumor-associated stroma. Much like a retrovirus, transposon-based plasmid vectors achieve integration into the genome, and thereby sustain transgene expression, which is especially important in actively mitotic cells such as tumor cells. Herein we briefly discuss the different transposons available for gene therapy applications, and provide a detailed protocol for nonviral transposon-based gene delivery to solid experimental tumors in mice.
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Affiliation(s)
- John R Ohlfest
- Department of Pediatrics, University of Minnesota, Minneapolis, MN, USA
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Suzuki M, Chiocca EA, Saeki Y. Stable transgene expression from HSV amplicon vectors in the brain: potential involvement of immunoregulatory signals. Mol Ther 2008; 16:1727-36. [PMID: 18728642 DOI: 10.1038/mt.2008.175] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The herpes simplex virus (HSV) amplicon is a plasmid-based, infectious gene delivery system that carries up to 150 kilobase (kb) of exogenous DNA. We previously characterized early host responses and stability of transgene expression in mice systemically injected with HSV amplicon vectors. Transgene expression was readily detected primarily in the liver but rapidly declined to undetectable levels within 2 weeks. Molecular analyses revealed induction of type I interferons (IFN) as the primary response, and early transcriptional silencing of the vector followed IFN's activation of signal transducers and activators of transcription 1 (STAT1). In this study, we investigate vector administration by stereotactic injection into the striatum. In the brain, induction of type I IFN was rather modest, and transgene expression lasted more than 1 year despite dose-dependent inflammation and infiltration of immune cells around injection sites. Further analyses revealed dose-dependent upregulation of immunosuppressive cytokines and molecular markers specific to regulatory T cells in the injected brain regions, which supported the immune-privileged properties of the brain parenchyma. Overall, our findings indicate that the spectrum of host responses can differ significantly depending on target organs and administrative routes, and that HSV amplicon vectors hold great potential for gene therapy of chronic neurological disorders.
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Affiliation(s)
- Masataka Suzuki
- Dardinger Laboratory for Neuro-oncology and Neurosciences, Department of Neurological Surgery, The Ohio State University Medical Center, Columbus, Ohio 43210, USA
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Voigt K, Izsvák Z, Ivics Z. Targeted gene insertion for molecular medicine. J Mol Med (Berl) 2008; 86:1205-19. [PMID: 18607557 DOI: 10.1007/s00109-008-0381-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Revised: 05/22/2008] [Accepted: 05/27/2008] [Indexed: 11/24/2022]
Abstract
Genomic insertion of a functional gene together with suitable transcriptional regulatory elements is often required for long-term therapeutical benefit in gene therapy for several genetic diseases. A variety of integrating vectors for gene delivery exist. Some of them exhibit random genomic integration, whereas others have integration preferences based on attributes of the targeted site, such as primary DNA sequence and physical structure of the DNA, or through tethering to certain DNA sequences by host-encoded cellular factors. Uncontrolled genomic insertion bears the risk of the transgene being silenced due to chromosomal position effects, and can lead to genotoxic effects due to mutagenesis of cellular genes. None of the vector systems currently used in either preclinical experiments or clinical trials displays sufficient preferences for target DNA sequences that would ensure appropriate and reliable expression of the transgene and simultaneously prevent hazardous side effects. We review in this paper the advantages and disadvantages of both viral and non-viral gene delivery technologies, discuss mechanisms of target site selection of integrating genetic elements (viruses and transposons), and suggest distinct molecular strategies for targeted gene delivery.
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Affiliation(s)
- Katrin Voigt
- Max Delbrück Center for Molecular Medicine, Robert-Rössle Strasse 10, 13092, Berlin, Germany
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Cuchet D, Epstein AL. Further improvements in the technology of HSV-1-based amplicon vectors. Expert Opin Ther Pat 2008. [DOI: 10.1517/13543776.18.7.797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Virus-mediated gene delivery to neuronal progenitors. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008. [PMID: 18188939 DOI: 10.1007/978-0-387-74904-4_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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Cuchet D, Potel C, Thomas J, Epstein AL. HSV-1 amplicon vectors: a promising and versatile tool for gene delivery. Expert Opin Biol Ther 2007; 7:975-95. [PMID: 17665988 DOI: 10.1517/14712598.7.7.975] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Amplicons are defective and non-integrative vectors derived from herpes simplex virus type 1. They carry no virus genes in the vector genome and are, therefore, not toxic to the infected cells or pathogenic for the transduced organisms, making these vectors safe. In addition, the large transgenic capacity of amplicons, which allow delivery of < or = 150 Kbp of foreign DNA, make these vectors one of the most powerful, interesting and versatile gene delivery platforms. Here, the authors present recent technological developments that have significantly improved and extended the use of amplicons, both in cultured cells and in living organisms. In addition, this review illustrates the many possible applications that are presently being developed with amplicons and discuss the many difficulties still pending to be solved in order to achieve stable and physiologically regulated transgenic expression.
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Peterson EB, Mastrangelo MA, Federoff HJ, Bowers WJ. Neuronal specificity of HSV/sleeping beauty amplicon transduction in utero is driven primarily by tropism and cell type composition. Mol Ther 2007; 15:1848-55. [PMID: 17653102 PMCID: PMC2587304 DOI: 10.1038/sj.mt.6300267] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
A novel bipartite vector system consisting of the herpes simplex virus (HSV) amplicon and the Sleeping Beauty(SB) transposon was previously shown to efficiently deliver a "transgenon" (integrating transgene) in utero. This vector platform facilitated long-term transgenon expression specifically within neurons and neuronal precursor cells of the rodent brain. However, the mechanism underlying the neurospecificity of the HSV/SB amplicon in the setting of mouse embryogenesis is unknown. We find that embryonic cells expressing the Sox1 "neurocompetence" transcription factor represent the primary targets for HSV amplicon transduction in utero. These cells, which comprise the ependymal and subventricular zones (SVZs), express significant levels of high-mobility-group protein B1 (HMGB1), a co-factor shown to facilitate SB-mediated transposition. Using a conventional, non-integrating amplicon expressing Cre recombinase to "tag" transduced cells embryonically in ROSA26 Cre indicator mice in utero, we found transduced cells were exclusively of the neuronal lineage but that in comparison to HSV/SB-mediated in utero delivery, staining patterns were less widespread and "tagged" neuroprogenitor cells were absent. Our findings demonstrate that in utero HSV/SB amplicon gene transfer is primarily neurospecific owing to viral tropism and target cell populations present embryonically, where multi-potent cells of the developing embryo are supportive of SB-driven transposition.
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Affiliation(s)
- Elise B. Peterson
- Center for Aging and Developmental Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
- Aab Institute of Biomedical Sciences, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
| | - Michael A. Mastrangelo
- Center for Aging and Developmental Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
- Aab Institute of Biomedical Sciences, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
| | - Howard J. Federoff
- Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
- Center for Aging and Developmental Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
- Aab Institute of Biomedical Sciences, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
| | - William J. Bowers
- Department of Neurology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
- Center for Aging and Developmental Biology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
- Aab Institute of Biomedical Sciences, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642
- Corresponding Author William J. Bowers, Ph.D. Department of Neurology Center for Aging and Developmental Biology Aab Institute for Biomedical Sciences University of Rochester School of Medicine and Dentistry 601 Elmwood Ave., Box 645 Rochester, NY 14642 USA Phone: 585−273−2195 Fax: 585−276−1957
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Abstract
Safe and effective delivery of genetic material to mammalian tissues would significantly expand the therapeutic possibilities for a large number of medical conditions. Unfortunately, the promise of gene therapy has been hampered by technical challenges, the induction of immune responses, and inadequate expression over time. Despite these setbacks, progress continues to be made and the anticipated benefits may come to fruition for certain disorders. In terms of delivery, nonviral vector systems are particularly attractive as they are simple to produce, can be stored for long periods of time, and induce no specific immune responses. A significant drawback to nonviral systems has been the lack of persistent expression, as plasmids are lost or degraded when delivered to living tissues. The recent application of integrating transposons to nonviral gene delivery has significantly helped to overcome this obstacle, because it allows for genomic integration and long-term expression. Recent advances in transposon-based vector systems hold promise as new technologies that may unlock the potential of gene therapy; however, technical and safety issues still need refinement.
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Affiliation(s)
- Stephen Fernando
- Department of Pharmacology and Therapeutics, College of Medicine, University of Florida, Gainesville, Florida 32610-0267, USA
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Saeki Y. Stable CNS gene delivery with Sleeping Beauty armed with a high-capacity HSV virion. Mol Ther 2006; 13:457-8. [PMID: 16461007 DOI: 10.1016/j.ymthe.2006.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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