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Stevens M, Star E, Lee M, Innes E, Li L, Bowler E, Harper S, Bates DO, Oltean S. The VEGF-A exon 8 splicing-sensitive fluorescent reporter mouse is a novel tool to assess the effects of splicing regulatory compounds in vivo. RNA Biol 2019; 16:1672-1681. [PMID: 31432737 PMCID: PMC6844573 DOI: 10.1080/15476286.2019.1652522] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Vascular endothelial growth factor (VEGF)-A is differentially spliced to give two functionally different isoform families; pro-angiogenic, pro-permeability VEGF-Axxx and anti-angiogenic, anti-permeability VEGF-Axxxb. VEGF-A splicing is dysregulated in several pathologies, including cancer, diabetes, and peripheral arterial disease. The bichromatic VEGF-A splicing-sensitive fluorescent reporter harboured in a transgenic mouse is a novel approach to investigate the splicing patterns of VEGF-A in vivo. We generated a transgenic mouse harbouring a splicing-sensitive fluorescent reporter designed to mimic VEGF-A terminal exon splicing (VEGF8ab) by insertion into the ROSA26 genomic locus. dsRED expression denotes proximal splice site selection (VEGF-Axxx) and eGFP expression denotes distal splice site selection (VEGF-Axxxb). We investigated the tissue-specific expression patterns in the eye, skeletal muscle, cardiac muscle, kidney, and pancreas, and determined whether the splicing pattern could be manipulated in the same manner as endogenous VEGF-A by treatment with the SRPK1 inhibitor SPHINX 31. We confirmed expression of both dsRED and eGFP in the eye, skeletal muscle, cardiac muscle, kidney, and pancreas, with the highest expression of both fluorescent proteins observed in the exocrine pancreas. The ratio of dsRED and eGFP matched that of endogenous VEGF-Axxx and VEGF-Axxxb. Treatment of the VEGF8ab mice with SPHINX 31 increased the mRNA and protein eGFP/dsRED ratio in the exocrine pancreas, mimicking endogenous VEGF-A splicing. The VEGF-A exon 8 splicing-sensitive fluorescent reporter mouse is a novel tool to assess splicing regulation in the individual cell-types and tissues, which provides a useful screening process for potentially therapeutic splicing regulatory compounds in vivo.
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Affiliation(s)
- M Stevens
- Institute of Biomedical and Clinical Science, Medical School, College of Medicine and Health, University of Exeter, Exeter, UK
| | - E Star
- Bristol Renal, School of Clinical Sciences, University of Bristol, Bristol, UK
| | - M Lee
- Bristol Renal, School of Clinical Sciences, University of Bristol, Bristol, UK
| | - E Innes
- Institute of Biomedical and Clinical Science, Medical School, College of Medicine and Health, University of Exeter, Exeter, UK
| | - L Li
- Institute of Biomedical and Clinical Science, Medical School, College of Medicine and Health, University of Exeter, Exeter, UK
| | - E Bowler
- Institute of Biomedical and Clinical Science, Medical School, College of Medicine and Health, University of Exeter, Exeter, UK
| | - S Harper
- Institute of Biomedical and Clinical Science, Medical School, College of Medicine and Health, University of Exeter, Exeter, UK.,School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, UK
| | - D O Bates
- Cancer Biology, Division of Cancer and Stem Cells, School of Medicine, University of Nottingham, Nottingham, UK
| | - S Oltean
- Institute of Biomedical and Clinical Science, Medical School, College of Medicine and Health, University of Exeter, Exeter, UK
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2
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Rizzi N, Rebecchi M, Levandis G, Ciana P, Maggi A. Identification of novel loci for the generation of reporter mice. Nucleic Acids Res 2017; 45:e37. [PMID: 27899606 PMCID: PMC5389565 DOI: 10.1093/nar/gkw1142] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 11/08/2016] [Indexed: 12/25/2022] Open
Abstract
Deciphering the etiology of complex pathologies at molecular level requires longitudinal studies encompassing multiple biochemical pathways (apoptosis, proliferation, inflammation, oxidative stress). In vivo imaging of current reporter animals enabled the spatio-temporal analysis of specific molecular events, however, the lack of a multiplicity of loci for the generalized and regulated expression of the integrated transgenes hampers the creation of systems for the simultaneous analysis of more than a biochemical pathways at the time. We here developed and tested an in vivo-based methodology for the identification of multiple insertional loci suitable for the generation of reliable reporter mice. The validity of the methodology was tested with the generation of novel mice useful to report on inflammation and oxidative stress.
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Affiliation(s)
- Nicoletta Rizzi
- Center of Excellence on Neurodegenerative Diseases and Department of Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti 9 20133 Milan, Italy
| | - Monica Rebecchi
- Center of Excellence on Neurodegenerative Diseases and Department of Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti 9 20133 Milan, Italy
| | - Giovanna Levandis
- Center of Excellence on Neurodegenerative Diseases and Department of Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti 9 20133 Milan, Italy
| | - Paolo Ciana
- Center of Excellence on Neurodegenerative Diseases and Department of Oncology and Hemato-Oncology (DIPO), University of Milan, Via Balzaretti 9 20133 Milan, Italy
| | - Adriana Maggi
- Center of Excellence on Neurodegenerative Diseases and Department of Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti 9 20133 Milan, Italy
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3
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Abstract
Generation and characterization of transgenic mice are important elements of biomedical research. In recent years, transgenic technology has become more versatile and sophisticated, mainly because of the incorporation of recombinase-mediated conditional expression and targeted insertion, site-specific endonuclease-mediated genome editing, siRNA-mediated gene knockdown, various inducible gene expression systems, and fluorescent protein marking and tracking techniques. Site-specific recombinases (such as PhiC31) and engineered endonucleases (such as ZFN and Talen) have significantly enhanced our ability to target transgenes into specific genomic loci, but currently a great majority of transgenic mouse lines are continuingly being created using the conventional random insertion method. A major challenge for using this conventional method is that the genomic environment at the integration site has a substantial influence on the expression of the transgene. Although our understanding of such chromosomal position effects and our means to combat them are still primitive, adhering to some general guidelines can significantly increase the odds of successful transgene expression. This chapter first discusses the major problems associated with transgene expression, and then describes some of the principles for using plasmid and bacterial artificial chromosomes (BACs) for generating transgenic constructs. Finally, the strategies for conducting each of the major types of transgenic research are discussed, including gene overexpression, promoter characterization, cell-lineage tracing, mutant complementation, expression of double or multiple transgenes, siRNA knockdown, and conditional and inducible systems.
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Affiliation(s)
- Lita A. Freeman
- grid.279885.90000000122934638Pulmonary & Vascular Medicine Branch, National Institutes of Health (NIH) National Heart, Lung & Blood Institute, Bethesda, Maryland USA
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4
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Silencing of fat-1 transgene expression in sheep may result from hypermethylation of its driven cytomegalovirus (CMV) promoter. Theriogenology 2012; 78:793-802. [DOI: 10.1016/j.theriogenology.2012.03.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Revised: 03/15/2012] [Accepted: 03/15/2012] [Indexed: 11/18/2022]
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5
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Zhang Y, Xi Q, Ding J, Cai W, Meng F, Zhou J, Li H, Jiang Q, Shu G, Wang S, Zhu X, Gao P, Wu Z. Production of transgenic pigs mediated by pseudotyped lentivirus and sperm. PLoS One 2012; 7:e35335. [PMID: 22536374 PMCID: PMC3335058 DOI: 10.1371/journal.pone.0035335] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Accepted: 03/14/2012] [Indexed: 11/18/2022] Open
Abstract
Sperm-mediated gene transfer can be a very efficient method to produce transgenic pigs, however, the results from different laboratories had not been widely repeated. Genomic integration of transgene by injection of pseudotyped lentivirus to the perivitelline space has been proved to be a reliable route to generate transgenic animals. To test whether transgene in the lentivirus can be delivered by sperm, we studied incubation of pseudotyped lentiviruses and sperm before insemination. After incubation with pig spermatozoa, 62±3 lentiviral particles were detected per 100 sperm cells using quantitative real-time RT-PCR. The association of lentivirus with sperm was further confirmed by electron microscopy. The sperm incubated with lentiviral particles were artificially inseminated into pigs. Of the 59 piglets born from inseminated 5 sows, 6 piglets (10.17%) carried the transgene based on the PCR identification. Foreign gene and EGFP was successfully detected in ear tissue biopsies from two PCR-positive pigs, revealed via in situ hybridization and immunohistochemistry. Offspring of one PCR-positive boar with normal sows showed PCR-positive. Two PCR-positive founders and offsprings of PCR-positive boar were further identified by Southern-blot analysis, out of which the two founders and two offsprings were positive in Southern blotting, strongly indicating integration of foreign gene into genome. The results indicate that incubation of sperm with pseudotyped lentiviruses can incorporated with sperm-mediated gene transfer to produce transgenic pigs with improved efficiency.
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Affiliation(s)
- Yongliang Zhang
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Qianyun Xi
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
- * E-mail: (QYX); (ZFW)
| | - Jinghua Ding
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Weiguang Cai
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Fanmin Meng
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Junyun Zhou
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Hongyi Li
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Qingyan Jiang
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Gang Shu
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Songbo Wang
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Xiaotong Zhu
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Ping Gao
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
| | - Zhenfang Wu
- Guangdong Provincial Key Laboratory of Agro-Animal Genomics and Molecular Breeding, College of Animal Science, South China Agricultural University, Guangzhou, China
- * E-mail: (QYX); (ZFW)
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Ward JE, Ren R, Toraldo G, Soohoo P, Guan J, O'Hara C, Jasuja R, Trinkaus-Randall V, Liao R, Connors LH, Seldin DC. Doxycycline reduces fibril formation in a transgenic mouse model of AL amyloidosis. Blood 2011; 118:6610-7. [PMID: 21998211 PMCID: PMC3242721 DOI: 10.1182/blood-2011-04-351643] [Citation(s) in RCA: 111] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Accepted: 09/22/2011] [Indexed: 12/17/2022] Open
Abstract
Systemic AL amyloidosis results from the aggregation of an amyloidogenic immunoglobulin (Ig) light chain (LC) usually produced by a plasma cell clone in the bone marrow. AL is the most rapidly fatal of the systemic amyloidoses, as amyloid fibrils can rapidly accumulate in tissues including the heart, kidneys, autonomic or peripheral nervous systems, gastrointestinal tract, and liver. Chemotherapy is used to eradicate the cellular source of the amyloidogenic precursor. Currently, there are no therapies that target the process of LC aggregation, fibril formation, or organ damage. We developed transgenic mice expressing an amyloidogenic λ6 LC using the cytomegalovirus (CMV) promoter to circumvent the disruption of B cell development by premature expression of recombined LC. The CMV-λ6 transgenic mice develop neurologic dysfunction and Congophilic amyloid deposits in the stomach. Amyloid deposition was inhibited in vivo by the antibiotic doxycycline. In vitro studies demonstrated that doxycycline directly disrupted the formation of recombinant LC fibrils. Furthermore, treatment of ex vivo LC amyloid fibrils with doxycycline reduced the number of intact fibrils and led to the formation of large disordered aggregates. The CMV-λ6 transgenic model replicates the process of AL amyloidosis and is useful for testing the antifibril potential of orally available agents.
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Affiliation(s)
- Jennifer Ellis Ward
- Amyloid Treatment and Research Program, and Department of Medicine, Medicine, Boston University School of Medicine and Boston Medical Center, Boston, MA 02118, USA
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7
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CMV promoter is inadequate for expression of mutant human RyR2 in transgenic rabbits. J Pharmacol Toxicol Methods 2011; 63:180-5. [DOI: 10.1016/j.vascn.2010.09.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Revised: 09/19/2010] [Accepted: 09/21/2010] [Indexed: 11/22/2022]
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Abstract
The present study uses a novel approach to gene therapy in which plasmid DNA is targeted to the pancreas in vivo using ultrasound targeted microbubble destruction (UTMD) to achieve islet regeneration. Intravenous microbubbles carrying plasmids are destroyed within the pancreatic microcirculation by ultrasound, achieving local gene expression that is further targeted to beta-cells by a modified rat insulin promoter (RIP3.1). A series of genes implicated in endocrine development were delivered to rats 2 days after streptozotocin-induced diabetes. The genes PAX4, Nkx2.2, Nkx6.1, Ngn3, and Mafa produced alpha cell hyperplasia, but no significant improvement in beta cell mass or blood glucose 30 days after UTMD. In contrast, RIP3.1-NeuroD1 promoted islet regeneration from surviving beta-cells, with normalization of glucose, insulin, and C-peptide at 30 days. In a longer-term experiment, 4 of 6 rats had return of diabetes at 90 days, accompanied by beta cell apoptosis on Tunel staining. Pre-treatment with the JNK inhibitor SP600125 successfully blocked beta-cell apoptosis and resulted in restoration of beta cell mass and normalization of blood glucose for up to 90 days. This technique allows in vivo islet regeneration, restoration of beta cell mass, and normalization of blood sugar, insulin, and C-peptide in rats without viruses.
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9
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Modelling Myc inhibition as a cancer therapy. Nature 2008; 455:679-83. [PMID: 18716624 DOI: 10.1038/nature07260] [Citation(s) in RCA: 649] [Impact Index Per Article: 40.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2008] [Accepted: 07/11/2008] [Indexed: 12/21/2022]
Abstract
Myc is a pleiotropic basic helix-loop-helix leucine zipper transcription factor that coordinates expression of the diverse intracellular and extracellular programs that together are necessary for growth and expansion of somatic cells. In principle, this makes inhibition of Myc an attractive pharmacological approach for treating diverse types of cancer. However, enthusiasm has been muted by lack of direct evidence that Myc inhibition would be therapeutically efficacious, concerns that it would induce serious side effects by inhibiting proliferation of normal tissues, and practical difficulties in designing Myc inhibitory drugs. We have modelled genetically both the therapeutic impact and the side effects of systemic Myc inhibition in a preclinical mouse model of Ras-induced lung adenocarcinoma by reversible, systemic expression of a dominant-interfering Myc mutant. We show that Myc inhibition triggers rapid regression of incipient and established lung tumours, defining an unexpected role for endogenous Myc function in the maintenance of Ras-dependent tumours in vivo. Systemic Myc inhibition also exerts profound effects on normal regenerating tissues. However, these effects are well tolerated over extended periods and rapidly and completely reversible. Our data demonstrate the feasibility of targeting Myc, a common downstream conduit for many oncogenic signals, as an effective, efficient and tumour-specific cancer therapy.
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10
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Soucek L, Whitfield J, Martins CP, Finch AJ, Murphy DJ, Sodir NM, Karnezis AN, Swigart LB, Nasi S, Evan GI. Modelling Myc inhibition as a cancer therapy. Nature 2008. [PMID: 18716624 DOI: 10.1038/nature07260.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Myc is a pleiotropic basic helix-loop-helix leucine zipper transcription factor that coordinates expression of the diverse intracellular and extracellular programs that together are necessary for growth and expansion of somatic cells. In principle, this makes inhibition of Myc an attractive pharmacological approach for treating diverse types of cancer. However, enthusiasm has been muted by lack of direct evidence that Myc inhibition would be therapeutically efficacious, concerns that it would induce serious side effects by inhibiting proliferation of normal tissues, and practical difficulties in designing Myc inhibitory drugs. We have modelled genetically both the therapeutic impact and the side effects of systemic Myc inhibition in a preclinical mouse model of Ras-induced lung adenocarcinoma by reversible, systemic expression of a dominant-interfering Myc mutant. We show that Myc inhibition triggers rapid regression of incipient and established lung tumours, defining an unexpected role for endogenous Myc function in the maintenance of Ras-dependent tumours in vivo. Systemic Myc inhibition also exerts profound effects on normal regenerating tissues. However, these effects are well tolerated over extended periods and rapidly and completely reversible. Our data demonstrate the feasibility of targeting Myc, a common downstream conduit for many oncogenic signals, as an effective, efficient and tumour-specific cancer therapy.
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Affiliation(s)
- Laura Soucek
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, California 94143-0875, USA
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11
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Chen S, Ding J, Yu C, Yang B, Wood DR, Grayburn PA. Reversal of streptozotocin-induced diabetes in rats by gene therapy with betacellulin and pancreatic duodenal homeobox-1. Gene Ther 2007; 14:1102-10. [PMID: 17460716 DOI: 10.1038/sj.gt.3302963] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Ultrasound-targeted microbubble destruction (UTMD) was used to direct betacellulin (BTC) and pancreatic duodenal homeobox-1 (PDX1) to rat pancreas 48 h after islet destruction by streptozotocin (STZ). Sprague-Dawley rats were rendered diabetic by STZ injection. Controls included normal rats, STZ only without UTMD, and UTMD with DsRed reporter gene. Blood glucose increased dramatically in all rats 48 h after STZ, and continued to rise after UTMD with BTC alone. Blood glucose declined from day 3 to day 10 after UTMD with PDX1, but remained elevated (261+/-8 mg/dl). However, in rats treated with both BTC and PDX1, blood glucose remained below 200 mg/dl throughout day 10. This was accompanied by normalization of blood insulin and C-peptide. Histology demonstrated islet-like clusters of glucagon-staining cells in the rats treated with BTC and PDX1, but these clusters disappeared by 30 days after UTMD treatment. Although regeneration of insulin-producing islets was not seen, diabetes was reversed for up to 15 days after a single UTMD treatment by ectopic insulin production by pancreatic acinar cells. These cells co-expressed amylase and insulin and demonstrated several beta-cell markers by reverse transcription-PCR. Gene therapy by UTMD can reverse diabetes in vivo in adult rats by restoring pancreatic insulin production.
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Affiliation(s)
- S Chen
- Division of Cardiology, Department of Internal Medicine, Baylor University Medical Center, Baylor Heart and Vascular Institute, Dallas, TX 75226, USA
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12
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Chen S, Ding JH, Bekeredjian R, Yang BZ, Shohet RV, Johnston SA, Hohmeier HE, Newgard CB, Grayburn PA. Efficient gene delivery to pancreatic islets with ultrasonic microbubble destruction technology. Proc Natl Acad Sci U S A 2006; 103:8469-74. [PMID: 16709667 PMCID: PMC1482516 DOI: 10.1073/pnas.0602921103] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2005] [Indexed: 12/31/2022] Open
Abstract
This study describes a method of gene delivery to pancreatic islets of adult, living animals by ultrasound targeted microbubble destruction (UTMD). The technique involves incorporation of plasmids into the phospholipid shell of gas-filled microbubbles, which are then infused into rats and destroyed within the pancreatic microcirculation with ultrasound. Specific delivery of genes to islet beta cells by UTMD was achieved by using a plasmid containing a rat insulin 1 promoter (RIP), and reporter gene expression was regulated appropriately by glucose in animals that received a RIP-luciferase plasmid. To demonstrate biological efficacy, we used UTMD to deliver RIP-human insulin and RIP-hexokinase I plasmids to islets of adult rats. Delivery of the former plasmid resulted in clear increases in circulating human C-peptide and decreased blood glucose levels, whereas delivery of the latter plasmid resulted in a clear increase in hexokinase I protein expression in islets, increased insulin levels in blood, and decreased circulating glucose levels. We conclude that UTMD allows relatively noninvasive delivery of genes to pancreatic islets with an efficiency sufficient to modulate beta cell function in adult animals.
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Affiliation(s)
- Shuyuan Chen
- *Department of Internal Medicine, Cardiology Section, Baylor University Medical Center, Baylor Heart and Vascular Institute, 621 North Hall Street, Suite H030, Dallas, TX 75226
- Institute of Metabolic Disease, Baylor University Medical Center, Dallas, TX 75246
| | - Jia-huan Ding
- Institute of Metabolic Disease, Baylor University Medical Center, Dallas, TX 75246
| | | | - Bing-zhi Yang
- Institute of Metabolic Disease, Baylor University Medical Center, Dallas, TX 75246
| | - Ralph V. Shohet
- Department of Internal Medicine, Division of Cardiology, and
| | - Stephen A. Johnston
- Center for Biomedical Invention, University of Texas Southwestern Medical Center, Dallas, TX 75390; and
| | - Hans E. Hohmeier
- Sarah W. Stedman Nutrition and Metabolism Center, Departments of Pharmacology and Cancer Biology and Medicine, Duke University Medical Center, Durham, NC 27710
| | - Christopher B. Newgard
- Sarah W. Stedman Nutrition and Metabolism Center, Departments of Pharmacology and Cancer Biology and Medicine, Duke University Medical Center, Durham, NC 27710
| | - Paul A. Grayburn
- *Department of Internal Medicine, Cardiology Section, Baylor University Medical Center, Baylor Heart and Vascular Institute, 621 North Hall Street, Suite H030, Dallas, TX 75226
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Hrabovska A, Duysen EG, Sanders JD, Murrin LC, Lockridge O. Delivery of human acetylcholinesterase by adeno-associated virus to the acetylcholinesterase knockout mouse. Chem Biol Interact 2005; 157-158:71-8. [PMID: 16243306 DOI: 10.1016/j.cbi.2005.10.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The purpose of this work was to develop a gene delivery system that expressed acetylcholinesterase (AChE) for prolonged periods. An adeno-associated virus (AAV) expressing human AChE was constructed by co-transfecting three plasmids into HEK 293T cells. The purified vector expressed 0.17 microg AChE per 1 million viral particles in culture medium in 23 h, or 0.8 U/ml. The AAV/hAChE was injected into muscle of adult AChE knockout mice and into the brains of 3-6 week old AChE knockout mice. Intramuscular injection yielded plasma AChE levels approaching 50% of the AChE activity of wild-type mouse plasma. The highest AChE activity was found on day 3 post-injection. AChE activity declined thereafter to a constant 7% of normal. The decreased level was accompanied by the appearance of anti-human AChE antibodies, suggesting partial clearance of AChE from plasma by antibodies. Intrastriatal injection resulted in AChE expression in the striatum. No antibodies were detected in animals treated intrastriatally. Motor coordination was improved and the lifespan of intrastriatally-treated AChE knockout mice was prolonged. Human AChE was expressed in mouse brain for up to 7 months after intrastriatal injection of an AAV/hAChE construct. Gene-therapy to supply AChE to the striatum improved motor coordination and prolonged the life of mice genetically deficient in AChE, probably by reducing their susceptibility to spontaneous seizures. This supports the hypothesis that their seizures are induced by excess acetylcholine.
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Affiliation(s)
- Anna Hrabovska
- Eppley Institute, University of Nebraska Medical Center, 986805 Nebraska Medical Center, Omaha, NE 68198-6805, USA.
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14
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Collaco AM, Rahman S, Dougherty EJ, Williams BB, Geusz ME. Circadian Regulation of a Viral Gene Promoter in Live Transgenic Mice Expressing Firefly Luciferase. Mol Imaging Biol 2005; 7:342-50. [PMID: 16240059 DOI: 10.1007/s11307-005-0019-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE This study was conducted to test for possible circadian control of viral infection in live animals using bioluminescence imaging of a firefly luciferase transgene. METHODS Transgenic mice expressing the firefly luciferase gene under the control of the promoter and enhancer of the human cytomegalovirus major immediate-early gene (CMV::luc) were examined through whole-animal imaging. Mice were crossed with HRS/J hairless albino mice to improve imaging of deep structures. RESULTS Transgene expression in the extremities and head was elevated around dusk in mice maintained in cycles of light and dark. Signal was also elevated during the animal's night in mice maintained in extended darkness. The viral promoter was induced during the active phase of the circadian locomotor rhythm in several tissues. Both the acinar cells and islets expressed the transgene in dissociated pancreas cultures. CONCLUSIONS These results suggest that viruses may exploit the circadian system for optimal timing of infection at particular phases in several tissue types.
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Affiliation(s)
- Anne M Collaco
- Department of Biological Sciences and the J.P. Scott Center for Neuroscience, Mind, and Behavior, Bowling Green State University, Bowling Green, OH, USA
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15
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Thien CBF, Blystad FD, Zhan Y, Lew AM, Voigt V, Andoniou CE, Langdon WY. Loss of c-Cbl RING finger function results in high-intensity TCR signaling and thymic deletion. EMBO J 2005; 24:3807-19. [PMID: 16211006 PMCID: PMC1276723 DOI: 10.1038/sj.emboj.7600841] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2005] [Accepted: 09/19/2005] [Indexed: 01/15/2023] Open
Abstract
Signaling from the T-cell receptor (TCR) in thymocytes is negatively regulated by the RING finger-type ubiquitin ligase c-Cbl. To further investigate this regulation, we generated mice with a loss-of-function mutation in the c-Cbl RING finger domain. These mice exhibit complete thymic deletion by young adulthood, which is not caused by a developmental block, lack of progenitors or peripheral T-cell activation. Rather, this phenotype correlates with greatly increased expression of the CD5 and CD69 activation markers and increased sensitivity to anti-CD3-induced cell death. Thymic loss contrasts the normal fate of the c-Cbl-/- thymus, even though thymocytes from both mutant mice show equivalent enhancement in proximal TCR signaling, Erk activation and calcium mobilization. Remarkably, only the RING finger mutant thymocytes show prominent TCR-directed activation of Akt. We show that the mutant c-Cbl protein itself is essential for activating this pathway by recruiting the p85 regulatory subunit of PI 3-kinase. This study provides a unique model for analyzing high-intensity TCR signals that cause thymocyte deletion and highlights multiple roles of c-Cbl in regulating this process.
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MESH Headings
- Amino Acid Substitution
- Animals
- Antigens, CD/analysis
- Antigens, Differentiation, T-Lymphocyte/analysis
- Apoptosis
- CD3 Complex/analysis
- CD5 Antigens/analysis
- Extracellular Signal-Regulated MAP Kinases/analysis
- Lectins, C-Type
- Lymphocyte Specific Protein Tyrosine Kinase p56(lck)/analysis
- Mice
- Mice, Transgenic
- Mutation
- Phosphatidylinositol 3-Kinases/metabolism
- Protein Structure, Tertiary
- Proto-Oncogene Proteins c-cbl/chemistry
- Proto-Oncogene Proteins c-cbl/genetics
- Proto-Oncogene Proteins c-cbl/physiology
- Receptors, Antigen, T-Cell/immunology
- Receptors, Antigen, T-Cell/physiology
- Signal Transduction
- Thymus Gland/immunology
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Affiliation(s)
- Christine B F Thien
- School of Surgery and Pathology, University of Western Australia, Crawley, Australia
| | - Frøydis D Blystad
- School of Surgery and Pathology, University of Western Australia, Crawley, Australia
| | - Yifan Zhan
- The Walter and Eliza Hall Institute of Medical Research, Royal Parade, Melbourne, Australia
| | - Andrew M Lew
- The Walter and Eliza Hall Institute of Medical Research, Royal Parade, Melbourne, Australia
| | - Valentina Voigt
- Centre for Experimental Immunology, The Lions Eye Institute, Nedlands, Australia
| | | | - Wallace Y Langdon
- School of Surgery and Pathology, University of Western Australia, Crawley, Australia
- School of Surgery and Pathology, University of Western Australia, Crawley, WA 6009, Australia. Tel.: +61 8 9346 2939; Fax: +61 8 9346 2891; E-mail:
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16
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Zhan Y, Brown LE, Deliyannis G, Seah S, Wijburg OL, Price J, Strugnell RA, O'Connell PJ, Lew AM. Responses against complex antigens in various models of CD4 T-cell deficiency: surprises from an anti-CD4 antibody transgenic mouse. Immunol Res 2005; 30:1-14. [PMID: 15258307 DOI: 10.1385/ir:30:1:001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The most common models of CD4 T-cell deficiency are mice exogenously injected with anti-CD4 antibody (Ab), CD4 knockout (CD4-/-) and major histocompatibility complex (MHC) class II knockout (class II-/-) mice. We recently described the anti-CD4 Ab transgenic mouse (GK) as an improved CD4 cell-deficient model. This review compares this new GK mouse model with the widely available class II-/- and CD4-/- mice, when exposed to complex antigens (foreign grafts and during bacterial or viral infection). We highlight here the cytometric and functional differences (including Ab isotype, viral or bacterial clearance, and graft survival) among these CD4 cell-deficient models. For example, whereas grafts are generally rejected in class II-/- and CD4-/- mice as quickly as in wild-type mice, they survive longer in GK mice. Also, CD4-/- mice produce IgG against both simple model and complex antigens, but class II-/- and GK mice produce small amounts of IgG2a against complex antigens but not simple model antigens. These differences harbinger the caveats in the use of these various mice.
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Affiliation(s)
- Yifan Zhan
- Walter & Eliza Hall Institute of Medical Research, 1G Royal Parade, Melbourne 3050, Australia
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17
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McGrew MJ, Sherman A, Ellard FM, Lillico SG, Gilhooley HJ, Kingsman AJ, Mitrophanous KA, Sang H. Efficient production of germline transgenic chickens using lentiviral vectors. EMBO Rep 2004; 5:728-33. [PMID: 15192698 PMCID: PMC1299092 DOI: 10.1038/sj.embor.7400171] [Citation(s) in RCA: 256] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2004] [Revised: 02/27/2004] [Accepted: 04/26/2004] [Indexed: 01/29/2023] Open
Abstract
An effective method for genetic modification of chickens has yet to be developed. An efficient technology, enabling production of transgenic birds at high frequency and with reliable expression of transgenes, will have many applications, both in basic research and in biotechnology. We investigated the efficiency with which lentiviral vectors could transduce the chicken germ line and examined the expression of introduced reporter transgenes. Ten founder cockerels transmitted the vector to between 4% and 45% of their offspring and stable transmission to the G2 generation was demonstrated. Analysis of expression of reporter gene constructs in several transgenic lines showed a conserved expression profile between individuals that was maintained after transmission through the germ line. These data demonstrate that lentiviral vectors can be used to generate transgenic lines with an efficiency in the order of 100-fold higher than any previously published method, with no detectable silencing of transgene expression between generations.
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Affiliation(s)
| | | | - Fiona M Ellard
- Oxford Biomedica (UK) Ltd, Medawar Centre, The Oxford Science Park, Oxford OX4 4GA, UK
| | | | | | - Alan J Kingsman
- Oxford Biomedica (UK) Ltd, Medawar Centre, The Oxford Science Park, Oxford OX4 4GA, UK
| | | | - Helen Sang
- Roslin Institute, Roslin, Midlothian EH25 9PS, UK
- Tel: +44 131 527 4234; Fax: +44 131 440 0434; E-mail:
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18
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Mador N, Braun E, Haim H, Ariel I, Panet A, Steiner I. Transgenic mouse with the herpes simplex virus type 1 latency-associated gene: expression and function of the transgene. J Virol 2004; 77:12421-9. [PMID: 14610166 PMCID: PMC262558 DOI: 10.1128/jvi.77.23.12421-12429.2003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
During herpes simplex virus type 1 (HSV-1) latent infection in human peripheral sensory ganglia, the major viral gene transcribed is the latency-associated transcript (LAT) gene. In order to facilitate the study of this gene, we generated a transgenic mouse that contains the DNA fragment that transcribes the LAT RNAs (2.0 kb and its 1.5-kb spliced transcript) under control of the cytomegalovirus promoter. The tissue distribution of these transcripts and their effects upon HSV-1 replication, latency, and reactivation in the transgenic-mouse model were examined. Different steady-state amounts of both transcripts were found in various tissues. While the highest levels of the 2.0-kb RNA were detected in heart and skeletal muscle, the 1.5-kb transcript was found at elevated levels in the brain and at much higher levels in the trigeminal ganglia (TG). Replication of both the wild-type and a LAT-negative mutant virus was suppressed in primary embryonic fibroblasts obtained from LAT-expressing transgenic mice compared to that in cells obtained from normal mice. HSV-1 DNA amounts in latently infected TG of transgenic mice were similar to those in normal mice. Reactivation of latent HSV-1 LAT-negative mutants by explant cocultivation of TG from transgenic mice was more efficient than reactivation from normal-mouse TG. Considering our present and previous results, we propose that the significantly higher steady-state level of the 1.5-kb RNA in the TG may link this transcript to latency functions and that by inhibition of virus replication, the LAT gene may protect ganglion cells and thereby increase the probability of reactivation.
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Affiliation(s)
- Nurith Mador
- Clinical Virology Unit, Laboratory of Neurovirology, Hadassah University Hospital, Jerusalem, Israel
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19
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Collaco AM, Geusz ME. Monitoring immediate-early gene expression through firefly luciferase imaging of HRS/J hairless mice. BMC PHYSIOLOGY 2003; 3:8. [PMID: 12927048 PMCID: PMC194750 DOI: 10.1186/1472-6793-3-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/19/2003] [Accepted: 08/19/2003] [Indexed: 12/17/2022]
Abstract
BACKGROUND Gene promoters fused to the firefly luciferase gene (luc) are useful for examining gene regulation in live transgenic mice and they provide unique views of functioning organs. The dynamics of gene expression in cells and tissues expressing luciferase can be observed by imaging this enzyme's bioluminescent oxidation of luciferin. Neural pathways involved in specific behaviors have been identified by localizing expression of immediate-early genes such as c-fos. A transgenic mouse line with luc controlled by the human c-fos promoter (fos::luc) has enabled gene expression imaging in brain slice cultures. To optimize imaging of immediate-early gene expression throughout intact mice, the present study examined fos::luc mice and a second transgenic mouse containing luc controlled by the human cytomegalovirus immediate-early gene 1 promoter and enhancer (CMV::luc). Because skin pigments and hair can significantly scatter light from underlying structures, the two transgenic lines were crossed with a hairless albino mouse (HRS/J) to explore which deep structures could be imaged. Furthermore, live anesthetized mice were compared with overdosed mice. RESULTS Bioluminescence imaging of anesthetized mice over several weeks corresponded with expression patterns in mice imaged rapidly after a lethal overdose. Both fos::luc and CMV::luc mice showed quantifiable bright bioluminescence in ear, nose, paws, and tail whether they were anesthetized or overdosed. CMV::luc and fos::luc neonates had bioluminescence patterns similar to those of adults, although intensity was significantly higher in neonates. CMV::luc mice crossed with HRS/J mice had high expression in bone, claws, head, pancreas, and skeletal muscle, but less in extremities than haired CMV::luc mice. Imaging of brain bioluminescence through the neonatal skull was also practical. By imaging luciferin autofluorescence it was clear that substrate distribution did not restrict bioluminescence imaging to capillaries after injection. Luciferin treatment and anesthesia during imaging did not adversely affect circadian rhythms in locomotor activity. CONCLUSIONS Imaging of gene expression patterns with luciferase can be extended from studies of live animals to rapid imaging of mice following a pentobarbital overdose before significant effects from postmortem changes occurs. Bioluminescent transgenic mice crossed with HRS/J mice are valuable for examining gene expression in deep tissues.
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Affiliation(s)
- Anne M Collaco
- Department of Biological Sciences and J. P. Scott Center for Neuroscience, Behavior and Mind, 217 Life Science Building, Bowling Green State University, Bowling Green, OH 43403-0212, USA
| | - Michael E Geusz
- Department of Biological Sciences and J. P. Scott Center for Neuroscience, Behavior and Mind, 217 Life Science Building, Bowling Green State University, Bowling Green, OH 43403-0212, USA
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Zhan Y, Purton JF, Godfrey DI, Cole TJ, Heath WR, Lew AM. Without peripheral interference, thymic deletion is mediated in a cohort of double-positive cells without classical activation. Proc Natl Acad Sci U S A 2003; 100:1197-202. [PMID: 12538873 PMCID: PMC298750 DOI: 10.1073/pnas.0237316100] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Peripheral activation can cause bystander thymocyte death by eliciting a "cytokine storm." This event complicates in vivo studies using exogenous ligand-induced models of negative selection. A stable transgenic model that selectively eliminates peripheral CD4 cells has allowed us to analyze negative selection as direct cognate events in two T cell receptor transgenic mice, OT-II and DO11. Whereas cognate peptide induced a massive deletion in double-positive (DP) cells in mice with peripheral CD4 cells, this DP deletion was modest in mice lacking peripheral CD4 cells. Using BrdUrd and annexin V staining, we found that negative selection primarily occurs in a cohort of DP cells and the absence of single-positive (SP) cells is largely caused by reduction in the cohort of DP precursors. Moreover, the fates of DP cells and SP cells after antigen exposure were vastly different. Whereas SP cells up-regulated uniformly their CD69 and CD44 levels, increased their cell size, and survived after antigen exposure, DP cells had less CD69 and CD44 up-regulation, no size change, and promptly died. Thus, negative selection represents an "abortive" activation different from activation-induced cell death of mature T cells.
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Affiliation(s)
- Yifan Zhan
- The Walter and Eliza Hall Institute of Medical Research, 1G Royal Parade, Melbourne 3050, Australia
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21
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Bi JX, Wirth M, Beer C, Kim EJ, Gu MB, Zeng AP. Dynamic characterization of recombinant Chinese hamster ovary cells containing an inducible c-fos promoter GFP expression system as a biomarker. J Biotechnol 2002; 93:231-42. [PMID: 11755987 DOI: 10.1016/s0168-1656(01)00400-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
An inducible reporter gene system for Chinese Hamster Ovary (CHO-DHFR(-)) cells has been developed and characterized with respect to its dynamic properties. The reporter gene system consists of the human c-fos promoter and variants of the green fluorescence protein (GFP), either EGFP with enhanced fluorescence or its destabilized form d2EGFP. The expression of wild-type EGFP or its destabilized form was studied in CHO-DHFR(-) cells in response to serum addition or deprivation. It was shown that serum-induced c-fos promoter mediated EGFP expression was considerably higher than expression from the human CMV promoter, a strong, constitutive promoter preferentially used for high-level expression in CHO cells. However, EGFP was less suitable for studying expression dynamics than d2EGFP due to the protein's long half-life in mammalian cells. The use of d2EGFP resulted in a significant improvement in the dynamic characteristics of the biomarker, particularly when the recombinant cells were selected for high-level GFP expression by subcloning or fluorescence activated cell/sorting (FACS). GFP expression in different subclones and cell populations sorted by FACS was characterized with respect to its dynamic responses in the presence or absence of serum in the culture medium. Significant differences in the GFP expression dynamics were observed for the isolated cell populations. The experimental results indicate that cells with high-level GFP expression also have a faster dynamic response and are thus, desirable for practical application of the reporter gene system e.g. in toxicity monitoring.
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Affiliation(s)
- J X Bi
- Biochemical Engineering Division, GBF-Gesellschaft für Biotechnologische Forschung mbH, Mascheroder Weg 1, D-38124 Braunschweig, Germany
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Abstract
Ubiquitous gene expression has a variety of applications in transgenesis that include, for example cell lineage analyses in chimeras and gain-of-function related to xenotransplantations. Although several promoters have already been used to these aims, they often do not reliably or reproducibly target gene expression in mice. We have recently reported the site-independent expression of a bacterial artificial chromosome (BAC)-derived goat alpha-lactalbumin transgene in the mammary gland of mice and the subsequent localisation within the insert of this BAC of the cyclin T1 locus. This ubiquitously expressed gene encodes for a protein that acts as a co-factor for the HIV nuclear transcriptional activator. In the present paper, we report that the goat BAC transgene, which encompasses around 30 kb of the cyclin T1 promoter, also confers ubiquitous expression of this gene in the six transgenic mouse lines analysed. These results suggest that the cyclin T1 promoter could be a useful alternative to target ubiquitous gene expression in transgenics.
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Affiliation(s)
- Xavier Mata
- Département de Génétique Animale, Institut National de la Recherche Agronomique, Jouy-en-Josas, France
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Wiekowski MT, Chen SC, Zalamea P, Wilburn BP, Kinsley DJ, Sharif WW, Jensen KK, Hedrick JA, Manfra D, Lira SA. Disruption of neutrophil migration in a conditional transgenic model: evidence for CXCR2 desensitization in vivo. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:7102-10. [PMID: 11739532 DOI: 10.4049/jimmunol.167.12.7102] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We developed transgenic mice conditionally expressing the neutrophil chemoattracting chemokine KC and the beta-galactosidase gene in multiple tissues. In these transgenic mice, doxycycline treatment induced a strong up-regulation in the expression of KC in several tissues, including heart, liver, kidney, skin, and skeletal muscle. Expression of KC within these tissues led to a rapid and substantial increase in the serum levels of KC (serum KC levels were higher than 200 ng/ml 24 h after treatment). Accordingly, beta-galactosidase expression was also detected after injection of doxycycline and was highest in skeletal muscle, pancreas, and liver. Surprisingly, despite expression of KC in multiple tissues, no neutrophil infiltration was observed in any of the tissues examined, including skin. Doxycycline treatment of nontransgenic mice grafted with transgenic skin caused dense neutrophilic infiltration of the grafts, but not the surrounding host skin, indicating that the KC produced in transgenic tissues was biologically active. In separate experiments, neutrophil migration toward a localized source of recombinant KC was impaired in animals overexpressing KC but was normal in response to other neutrophil chemoattractants. Analysis of transgenic neutrophils revealed that high concentrations of KC in transgenic blood had no influence on L-selectin cell surface expression but caused desensitization of the receptor for KC, CXCR2. These results confirm the neutrophil chemoattractant properties of KC and provide a mechanistic explanation for the paradoxical lack of leukocyte infiltration observed in the presence of elevated concentrations of this chemokine.
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Affiliation(s)
- M T Wiekowski
- Department of Immunology and Human Genome Research, Schering-Plough Research Institute, Kenilworth, NJ 07033, USA.
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