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Yasser M, Ribback S, Evert K, Utpatel K, Annweiler K, Evert M, Dombrowski F, Calvisi DF. Early Subcellular Hepatocellular Alterations in Mice Post Hydrodynamic Transfection: An Explorative Study. Cancers (Basel) 2023; 15:cancers15020328. [PMID: 36672277 PMCID: PMC9857294 DOI: 10.3390/cancers15020328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 12/29/2022] [Accepted: 12/30/2022] [Indexed: 01/06/2023] Open
Abstract
Hydrodynamic transfection (HT) or hydrodynamic tail vein injection (HTVi) is among the leading technique that is used to deliver plasmid genes mainly into the liver of live mice or rats. The DNA constructs are composed of coupled plasmids, while one contains the gene of interest that stably integrate into the hepatocyte genome with help of the other consisting sleeping beauty transposase system. The rapid injection of a large volume of DNA-solution through the tail vein induces an acute cardiac congestion that refluxed into the liver, mainly in acinus zone 3, also found through our EM study. Although, HT mediated hydrodynamic force can permeabilizes the fenestrated sinusoidal endothelium of liver, but the mechanism of plasmid incorporation into the hepatocytes remains unclear. Therefore, in the present study, we have hydrodynamically injected 2 mL volume of empty plasmid (transposon vector) or saline solution (control) into the tail vein of anesthetized C57BL/6J/129Sv mice. Liver tissue was resected at different time points from two animal group conditions, i.e., one time point per animal (1, 5, 10-20, 60 min or 24 and 48 hrs after HT) or multiple time points per animal (0, 1, 2, 5, 10, 20 min) and quickly fixed with buffered 4% osmium tetroxide. The tissues fed with only saline solution was also resected and fixed in the similar way. EM evaluation from the liver ultrathin sections reveals that swiftly after 1 min, the hepatocytes near to the central venule in the acinus zone 3 shows cytoplasmic membrane-bound vesicles. Such vesicles increased in both numbers and size to vacuoles and precisely often found in the proximity to the nucleus. Further, EM affirm these vacuoles are also optically empty and do not contain any electron dense material. Although, some of the other hepatocytes reveals sign of cell damage including swollen mitochondria, dilated endoplasmic reticulum, Golgi apparatus and disrupted plasma membrane, but most of the hepatocytes appeared normal. The ultrastructural findings in the mice injected with empty vector or saline injected control mice were similar. Therefore, we have interpreted the vacuole formation as nonspecific endocytosis without specific interactions at the plasma membrane.
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Affiliation(s)
- Mohd Yasser
- Institut fuer Pathologie, Universitaetsmedizin Greifswald, Friedrich-Loeffler-Str. 23e, 17475 Greifswald, Germany
| | - Silvia Ribback
- Institut fuer Pathologie, Universitaetsmedizin Greifswald, Friedrich-Loeffler-Str. 23e, 17475 Greifswald, Germany
- Correspondence:
| | - Katja Evert
- Institut fuer Pathologie, Universitaetsklinikum Regensburg, 93053 Regensburg, Germany
| | - Kirsten Utpatel
- Institut fuer Pathologie, Universitaetsklinikum Regensburg, 93053 Regensburg, Germany
| | - Katharina Annweiler
- Institut fuer Pathologie, Universitaetsmedizin Greifswald, Friedrich-Loeffler-Str. 23e, 17475 Greifswald, Germany
| | - Matthias Evert
- Institut fuer Pathologie, Universitaetsklinikum Regensburg, 93053 Regensburg, Germany
| | - Frank Dombrowski
- Institut fuer Pathologie, Universitaetsmedizin Greifswald, Friedrich-Loeffler-Str. 23e, 17475 Greifswald, Germany
| | - Diego F. Calvisi
- Institut fuer Pathologie, Universitaetsklinikum Regensburg, 93053 Regensburg, Germany
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Bhat A, Ghatage T, Bhan S, Lahane GP, Dhar A, Kumar R, Pandita RK, Bhat KM, Ramos KS, Pandita TK. Role of Transposable Elements in Genome Stability: Implications for Health and Disease. Int J Mol Sci 2022; 23:ijms23147802. [PMID: 35887150 PMCID: PMC9319628 DOI: 10.3390/ijms23147802] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 07/07/2022] [Accepted: 07/12/2022] [Indexed: 12/11/2022] Open
Abstract
Most living organisms have in their genome a sizable proportion of DNA sequences capable of mobilization; these sequences are commonly referred to as transposons, transposable elements (TEs), or jumping genes. Although long thought to have no biological significance, advances in DNA sequencing and analytical technologies have enabled precise characterization of TEs and confirmed their ubiquitous presence across all forms of life. These findings have ignited intense debates over their biological significance. The available evidence now supports the notion that TEs exert major influence over many biological aspects of organismal life. Transposable elements contribute significantly to the evolution of the genome by giving rise to genetic variations in both active and passive modes. Due to their intrinsic nature of mobility within the genome, TEs primarily cause gene disruption and large-scale genomic alterations including inversions, deletions, and duplications. Besides genomic instability, growing evidence also points to many physiologically important functions of TEs, such as gene regulation through cis-acting control elements and modulation of the transcriptome through epigenetic control. In this review, we discuss the latest evidence demonstrating the impact of TEs on genome stability and the underling mechanisms, including those developed to mitigate the deleterious impact of TEs on genomic stability and human health. We have also highlighted the potential therapeutic application of TEs.
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Affiliation(s)
- Audesh Bhat
- Centre for Molecular Biology, Central University of Jammu, Jammu 181143, India;
- Correspondence: (A.B.); (T.K.P.)
| | - Trupti Ghatage
- Department of Pharmacy, BITS-Pilani Hyderabad Campus, Hyderabad 500078, India; (T.G.); (G.P.L.); (A.D.)
| | - Sonali Bhan
- Centre for Molecular Biology, Central University of Jammu, Jammu 181143, India;
| | - Ganesh P. Lahane
- Department of Pharmacy, BITS-Pilani Hyderabad Campus, Hyderabad 500078, India; (T.G.); (G.P.L.); (A.D.)
| | - Arti Dhar
- Department of Pharmacy, BITS-Pilani Hyderabad Campus, Hyderabad 500078, India; (T.G.); (G.P.L.); (A.D.)
| | - Rakesh Kumar
- Department of Biotechnology, Shri Mata Vaishnav Devi University, Katra 182320, India;
| | - Raj K. Pandita
- Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA;
| | - Krishna M. Bhat
- Department of Molecular Medicine, University of South Florida, Tampa, FL 33612, USA;
| | - Kenneth S. Ramos
- Center for Genomics and Precision Medicine, Texas A&M College of Medicine, Houston, TX 77030, USA;
| | - Tej K. Pandita
- Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA;
- Center for Genomics and Precision Medicine, Texas A&M College of Medicine, Houston, TX 77030, USA;
- Correspondence: (A.B.); (T.K.P.)
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Noda M, Tatsumi K, Matsui H, Matsunari Y, Sato T, Fukuoka Y, Hotta A, Okano T, Kichikawa K, Sugimoto M, Shima M, Nishio K. Development of alternative gene transfer techniques for ex vivo and in vivo gene therapy in a canine model. Regen Ther 2021; 18:347-354. [PMID: 34584911 PMCID: PMC8441024 DOI: 10.1016/j.reth.2021.08.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/27/2021] [Accepted: 08/27/2021] [Indexed: 11/26/2022] Open
Abstract
INTRODUCTION Gene therapy have recently attracted much attention as a curative therapeutic option for inherited single gene disorders such as hemophilia. Hemophilia is a hereditary bleeding disorder caused by the deficiency of clotting activity of factor VIII (FVIII) or factor IX (FIX), and gene therapy for hemophilia using viral vector have been vigorously investigated worldwide. Toward further advancement of gene therapy for hemophilia, we have previously developed and validated the efficacy of novel two types of gene transfer technologies using a mouse model of hemophilia A. Here we investigated the efficacy and safety of the technologies in canine model. Especially, validations of technical procedures of the gene transfers for dogs were focused. METHODS Green fluorescence protein (GFP) gene were transduced into normal beagle dogs by ex vivo and in vivo gene transfer techniques. For ex vivo gene transfer, blood outgrowth endothelial cells (BOECs) derived from peripheral blood of normal dogs were transduced with GFP gene using lentivirus vector, propagated, fabricated as cell sheets, then implanted onto the omentum of the same dogs. For in vivo gene transfer, normal dogs were subjected to GFP gene transduction with non-viral piggyBac vector by liver-targeted hydrodynamic injections. RESULTS No major adverse events were observed during the gene transfers in both gene transfer systems. As for ex vivo gene transfer, histological findings from the omental biopsy performed 4 weeks after implantation revealed the tube formation by implanted GFP-positive BOECs in the sub-adipose tissue layer without any inflammatory findings, and the detected GFP signals were maintained over 6 months. Regarding in vivo gene transfer, analyses of liver biopsy samples revealed more than 90% of liver cells were positive for GFP signals in the injected liver lobes 1 week after gene transfers, then the signals gradually declined overtime. CONCLUSIONS Two types of gene transfer techniques were successfully applied to a canine model, and the transduced gene expressions persisted for a long term. Toward clinical application for hemophilia patients, practical assessments of therapeutic efficacy of these techniques will need to be performed using a dog model of hemophilia and FVIII (or FIX) gene.
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Affiliation(s)
- Masashi Noda
- Department of General Medicine, Nara Medical University, Kashihara, Japan
| | - Kohei Tatsumi
- Advanced Medical Science of Thrombosis and Hemostasis, Nara Medical University, Kashihara, Japan
| | - Hideto Matsui
- Department of General Medicine, Nara Medical University, Kashihara, Japan
| | | | - Takeshi Sato
- Department of Diagnostic Radiology and IVR, Nara Medical University, Kashihara, Japan
| | - Yasushi Fukuoka
- Department of Diagnostic Radiology and IVR, Nara Medical University, Kashihara, Japan
| | - Akitsu Hotta
- Department of Reprogramming Science, Center for iPS Cell Research and Application, Kyoto University, Kyoto, Japan
| | - Teruo Okano
- Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan
| | - Kimihiko Kichikawa
- Department of Diagnostic Radiology and IVR, Nara Medical University, Kashihara, Japan
| | - Mitsuhiko Sugimoto
- Department of General Medicine, Nara Medical University, Kashihara, Japan
| | | | - Kenji Nishio
- Department of General Medicine, Nara Medical University, Kashihara, Japan
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Huang Y, Kruse RL, Ding H, Itani MI, Morrison J, Wang ZZ, Selaru FM, Kumbhari V. Parameters of biliary hydrodynamic injection during endoscopic retrograde cholangio-pancreatography in pigs for applications in gene delivery. PLoS One 2021; 16:e0249931. [PMID: 33909609 PMCID: PMC8081268 DOI: 10.1371/journal.pone.0249931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 03/27/2021] [Indexed: 11/23/2022] Open
Abstract
The biliary system is routinely accessed for clinical purposes via endoscopic retrograde cholangiopancreatography (ERCP). We previously pioneered ERCP-mediated hydrodynamic injection in large animal models as an innovative gene delivery approach for monogenic liver diseases. However, the procedure poses potential safety concerns related mainly to liver or biliary tree injury. Here, we sought to further define biliary hydrodynamic injection parameters that are well-tolerated in a human-sized animal model. ERCP was performed in pigs, and hydrodynamic injection carried out using a novel protocol to reduce duct wall stress. Each pig was subjected to multiple repeated injections to expedite testing and judge tolerability. Different injection parameters (volume, flow rate) and injection port diameters were tested. Vital signs were monitored throughout the procedure, and liver enzyme panels were collected pre- and post-procedure. Pigs tolerated repeated biliary hydrodynamic injections with only occasional, mild, isolated elevation in aspartate aminotransferase (AST), which returned to normal levels within one day post-injection. All other liver tests remained unchanged. No upper limit of volume tolerance was reached, which suggests the biliary tree can readily transmit fluid into the vascular space. Flow rates up to 10 mL/sec were also tolerated with minimal disturbance to vital signs and no anatomic rupture of bile ducts. Measured intrabiliary pressure was up to 150 mmHg, and fluid-filled vesicles were induced in liver histology at high flow rates, mimicking the changes in histology observed in mouse liver after hydrodynamic tail vein injection. Overall, our investigations in a human-sized pig liver using standard clinical equipment suggest that ERCP-guided hydrodynamic injection will be safely tolerated in patients. Future investigations will interrogate if higher flow rates and pressure mediate higher DNA delivery efficiencies.
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Affiliation(s)
- Yuting Huang
- Division of Gastroenterology & Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Department of Medicine, University of Maryland Medical Center Midtown Campus, Baltimore, Maryland, United States of America
| | - Robert L. Kruse
- Department of Pathology, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Hui Ding
- Division of Gastroenterology & Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Division of Gastroenterology and Hepatology, Renji Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Mohamad I. Itani
- Division of Gastroenterology & Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Jonathan Morrison
- R Adams Cowley Shock Trauma Center, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Zack Z. Wang
- Division of Hematology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Florin M. Selaru
- Division of Gastroenterology & Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- * E-mail: (VK); (FMS)
| | - Vivek Kumbhari
- Division of Gastroenterology & Hepatology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- Division of Gastroenterology & Hepatology, Department of Medicine, Mayo Clinic College of Medicine and Science, Jacksonville, Florida, United States of America
- * E-mail: (VK); (FMS)
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Moscoso CG, Steer CJ. Liver targeted gene therapy: Insights into emerging therapies. DRUG DISCOVERY TODAY. TECHNOLOGIES 2020; 34:9-19. [PMID: 33357766 DOI: 10.1016/j.ddtec.2020.11.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 10/23/2020] [Accepted: 11/03/2020] [Indexed: 12/24/2022]
Abstract
The large number of monogenic metabolic disorders originating in the liver poses a unique opportunity for development of gene therapy modalities to pursue curative approaches. Various disorders have been successfully treated via liver-directed gene therapy, though most of the advances have been in animal models, with only limited success in clinical trials. Pre-clinical data in animals using non-viral approaches, including the Sleeping Beauty transposon system, are discussed. The various advances with viral vectors for liver-directed gene therapy are also a focus of this review, including retroviral, adenoviral, recombinant adeno-associated viral, and SV40 vectors. Genome editing techniques, including zinc finger nucleases, transcription activator-like effector nucleases and clustered regularly interspaced short palindromic repeats (CRISPR), are also described. Further, the various controversies in the field with regards to somatic vs. germline editing using CRISPR in humans are explored, while also highlighting the myriad of preclinical advances. Lastly, newer technologies are reviewed, including base editing and prime editing, which use CRISPR with exciting adjunctive properties to avoid double-stranded breaks and thus the recruitment of endogenous repair mechanisms. While encouraging results have been achieved recently, there are still significant challenges to overcome prior to the broad use of vector-based and genome editing techniques in the clinical arena. As these technologies mature, the promise of a cure for many disabling inherited metabolic disorders is within reach, and urgently needed.
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Affiliation(s)
- Carlos G Moscoso
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA.
| | - Clifford J Steer
- Department of Medicine, Division of Gastroenterology, Hepatology and Nutrition, University of Minnesota Medical School, Minneapolis, Minnesota 55455, USA; Department of Genetics, Cell Biology and Development, University of Minnesota Medical School, Minneapolis, Minnesota 55455 USA.
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7
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Preclinical and clinical advances in transposon-based gene therapy. Biosci Rep 2017; 37:BSR20160614. [PMID: 29089466 PMCID: PMC5715130 DOI: 10.1042/bsr20160614] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 10/26/2017] [Accepted: 10/30/2017] [Indexed: 02/08/2023] Open
Abstract
Transposons derived from Sleeping Beauty (SB), piggyBac (PB), or Tol2 typically require cotransfection of transposon DNA with a transposase either as an expression plasmid or mRNA. Consequently, this results in genomic integration of the potentially therapeutic gene into chromosomes of the desired target cells, and thus conferring stable expression. Non-viral transfection methods are typically preferred to deliver the transposon components into the target cells. However, these methods do not match the efficacy typically attained with viral vectors and are sometimes associated with cellular toxicity evoked by the DNA itself. In recent years, the overall transposition efficacy has gradually increased by codon optimization of the transposase, generation of hyperactive transposases, and/or introduction of specific mutations in the transposon terminal repeats. Their versatility enabled the stable genetic engineering in many different primary cell types, including stem/progenitor cells and differentiated cell types. This prompted numerous preclinical proof-of-concept studies in disease models that demonstrated the potential of DNA transposons for ex vivo and in vivo gene therapy. One of the merits of transposon systems relates to their ability to deliver relatively large therapeutic transgenes that cannot readily be accommodated in viral vectors such as full-length dystrophin cDNA. These emerging insights paved the way toward the first transposon-based phase I/II clinical trials to treat hematologic cancer and other diseases. Though encouraging results were obtained, controlled pivotal clinical trials are needed to corroborate the efficacy and safety of transposon-based therapies.
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Tipanee J, VandenDriessche T, Chuah MK. Transposons: Moving Forward from Preclinical Studies to Clinical Trials. Hum Gene Ther 2017; 28:1087-1104. [DOI: 10.1089/hum.2017.128] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Jaitip Tipanee
- Department of Gene Therapy and Regenerative Medicine, Free University of Brussels (VUB), Brussels, Belgium
| | - Thierry VandenDriessche
- Department of Gene Therapy and Regenerative Medicine, Free University of Brussels (VUB), Brussels, Belgium
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
| | - Marinee K. Chuah
- Department of Gene Therapy and Regenerative Medicine, Free University of Brussels (VUB), Brussels, Belgium
- Center for Molecular and Vascular Biology, Department of Cardiovascular Sciences, University of Leuven, Leuven, Belgium
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Huang M, Sun R, Huang Q, Tian Z. Technical Improvement and Application of Hydrodynamic Gene Delivery in Study of Liver Diseases. Front Pharmacol 2017; 8:591. [PMID: 28912718 PMCID: PMC5582077 DOI: 10.3389/fphar.2017.00591] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/15/2017] [Indexed: 12/13/2022] Open
Abstract
Development of an safe and efficient in vivo gene delivery method is indispensable for molecular biology research and the progress in the following gene therapy. Over the past few years, hydrodynamic gene delivery (HGD) with naked DNA has drawn increasing interest in both research and potential clinic applications due to its high efficiency and low risk in triggering immune responses and carcinogenesis in comparison to viral vectors. This method, involving intravenous injection (i.v.) of massive DNA in a short duration, gives a transient but high in vivo gene expression especially in the liver of small animals. In addition to DNA, it has also been shown to deliver other substance such as RNA, proteins, synthetic small compounds and even viruses in vivo. Given its ability to robustly mimic in vivo hepatitis B virus (HBV) production in liver, HGD has become a fundamental and important technology on HBV studies in our group and many other groups. Recently, there have been interesting reports about the applications and further improvement of this technology in other liver research. Here, we review the principle, safety, current application and development of hydrodynamic delivery in liver disease studies, and discuss its future prospects, clinical potential and challenges.
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Affiliation(s)
- Mei Huang
- Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery, Department of General Surgery, Anhui Provincial Hospital Affiliated with Anhui Medical UniversityHefei, China
| | - Rui Sun
- Institute of Immunology, School of Life Sciences and Medical Center, University of Science and Technology of ChinaHefei, China
| | - Qiang Huang
- Anhui Province Key Laboratory of Hepatopancreatobiliary Surgery, Department of General Surgery, Anhui Provincial Hospital Affiliated with Anhui Medical UniversityHefei, China
| | - Zhigang Tian
- Institute of Immunology, School of Life Sciences and Medical Center, University of Science and Technology of ChinaHefei, China
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Aronovich EL, Hyland KA, Hall BC, Bell JB, Olson ER, Rusten MU, Hunter DW, Ellinwood NM, McIvor RS, Hackett PB. Prolonged Expression of Secreted Enzymes in Dogs After Liver-Directed Delivery of Sleeping Beauty Transposons: Implications for Non-Viral Gene Therapy of Systemic Disease. Hum Gene Ther 2017; 28:551-564. [PMID: 28530135 DOI: 10.1089/hum.2017.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The non-viral, integrating Sleeping Beauty (SB) transposon system is efficient in treating systemic monogenic disease in mice, including hemophilia A and B caused by deficiency of blood clotting factors and mucopolysaccharidosis types I and VII caused by α-L-iduronidase (IDUA) and β-glucuronidase (GUSB) deficiency, respectively. Modified approaches of the hydrodynamics-based procedure to deliver transposons to the liver in dogs were recently reported. Using the transgenic canine reporter secreted alkaline phosphatase (cSEAP), transgenic protein in the plasma was demonstrated for up to 6 weeks post infusion. This study reports that immunosuppression of dogs with gadolinium chloride (GdCl3) prolonged the presence of cSEAP in the circulation up to 5.5 months after a single vector infusion. Transgene expression declined gradually but appeared to stabilize after about 2 months at approximately fourfold baseline level. Durability of transgenic protein expression in the plasma was inversely associated with transient increase of liver enzymes alanine transaminase and aspartate transaminase in response to the plasmid delivery procedure, which suggests a deleterious effect of hepatocellular toxicity on transgene expression. GdCl3 treatment was ineffective for repeat vector infusions. In parallel studies, dogs were infused with potentially therapeutic transposons. Activities of transgenic IDUA and GUSB in plasma peaked at 50-350% of wildtype, but in the absence of immunosuppression lasted only a few days. Transposition was detectable by excision assay only when the most efficient transposase, SB100X, was used. Dogs infused with transposons encoding canine clotting factor IX (cFIX) were treated with GdCl3 and showed expression profiles similar to those in cSEAP-infused dogs, with expression peaking at 40% wt (2 μg/mL). It is concluded that GdCl3 can support extended transgene expression after hydrodynamic introduction of SB transposons in dogs, but that alternative regimens will be required to achieve therapeutic levels of transgene products.
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Affiliation(s)
- Elena L Aronovich
- 1 Department of Genetics, Cell Biology and Development and Center for Genome Engineering, University of Minnesota , Minneapolis, Minnesota
| | | | - Bryan C Hall
- 1 Department of Genetics, Cell Biology and Development and Center for Genome Engineering, University of Minnesota , Minneapolis, Minnesota
| | - Jason B Bell
- 1 Department of Genetics, Cell Biology and Development and Center for Genome Engineering, University of Minnesota , Minneapolis, Minnesota
| | - Erik R Olson
- 2 Discovery Genomics, Inc. , Minneapolis, Minnesota
| | - Myra Urness Rusten
- 3 Department of Radiology, University of Minnesota , Minneapolis, Minnesota
| | - David W Hunter
- 3 Department of Radiology, University of Minnesota , Minneapolis, Minnesota
| | | | - R Scott McIvor
- 1 Department of Genetics, Cell Biology and Development and Center for Genome Engineering, University of Minnesota , Minneapolis, Minnesota.,2 Discovery Genomics, Inc. , Minneapolis, Minnesota
| | - Perry B Hackett
- 1 Department of Genetics, Cell Biology and Development and Center for Genome Engineering, University of Minnesota , Minneapolis, Minnesota.,2 Discovery Genomics, Inc. , Minneapolis, Minnesota
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