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Hussein M, Andrade dos Ramos Z, Vink MA, Kroon P, Yu Z, Enjuanes L, Zuñiga S, Berkhout B, Herrera-Carrillo E. Efficient CRISPR-Cas13d-Based Antiviral Strategy to Combat SARS-CoV-2. Viruses 2023; 15:v15030686. [PMID: 36992394 PMCID: PMC10051389 DOI: 10.3390/v15030686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 03/08/2023] Open
Abstract
The current SARS-CoV-2 pandemic forms a major global health burden. Although protective vaccines are available, concerns remain as new virus variants continue to appear. CRISPR-based gene-editing approaches offer an attractive therapeutic strategy as the CRISPR-RNA (crRNA) can be adjusted rapidly to accommodate a new viral genome sequence. This study aimed at using the RNA-targeting CRISPR-Cas13d system to attack highly conserved sequences in the viral RNA genome, thereby preparing for future zoonotic outbreaks of other coronaviruses. We designed 29 crRNAs targeting highly conserved sequences along the complete SARS-CoV-2 genome. Several crRNAs demonstrated efficient silencing of a reporter with the matching viral target sequence and efficient inhibition of a SARS-CoV-2 replicon. The crRNAs that suppress SARS-CoV-2 were also able to suppress SARS-CoV, thus demonstrating the breadth of this antiviral strategy. Strikingly, we observed that only crRNAs directed against the plus-genomic RNA demonstrated antiviral activity in the replicon assay, in contrast to those that bind the minus-genomic RNA, the replication intermediate. These results point to a major difference in the vulnerability and biology of the +RNA versus −RNA strands of the SARS-CoV-2 genome and provide important insights for the design of RNA-targeting antivirals.
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Affiliation(s)
- Mouraya Hussein
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Zaria Andrade dos Ramos
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Monique A. Vink
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Pascal Kroon
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Zhenghao Yu
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Luis Enjuanes
- Department of Molecular and Cell Biology, National Center of Biotechnology (CNB-CSIC), Campus Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Sonia Zuñiga
- Department of Molecular and Cell Biology, National Center of Biotechnology (CNB-CSIC), Campus Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Ben Berkhout
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
| | - Elena Herrera-Carrillo
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands
- Correspondence:
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Arslan F, Damman P, Zwart B, Appelman Y, Voskuil M, de Vos A, van Royen N, Jukema JW, Waalewijn R, Hermanides RS, Woudstra P, Ten Cate T, Lemkes JS, Vink MA, Balder W, van der Wielen MLJ, Vlaar PJ, van der Heijden DJ, Assa S, van 't Hof AW, Ten Berg JM. 2020 ESC Guidelines on acute coronary syndrome without ST-segment elevation : Recommendations and critical appraisal from the Dutch ACS and Interventional Cardiology working groups. Neth Heart J 2021; 29:557-565. [PMID: 34232481 PMCID: PMC8556454 DOI: 10.1007/s12471-021-01593-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2021] [Indexed: 11/27/2022] Open
Abstract
Recently, the European Society of Cardiology (ESC) has updated its guidelines for the management of patients with acute coronary syndrome (ACS) without ST-segment elevation. The current consensus document of the Dutch ACS working group and the Working Group of Interventional Cardiology of the Netherlands Society of Cardiology aims to put the 2020 ESC Guidelines into the Dutch perspective and to provide practical recommendations for Dutch cardiologists, focusing on antiplatelet therapy, risk assessment and criteria for invasive strategy.
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Affiliation(s)
- F Arslan
- Vivantes Klinikum am Urban, Berlin, Germany.,St. Antonius Hospital, Nieuwegein, The Netherlands
| | - P Damman
- Radboud University Medical Center, Nijmegen, The Netherlands.
| | - B Zwart
- Elisabeth-TweeSteden Hospital, Tilburg, The Netherlands
| | - Y Appelman
- Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - M Voskuil
- University Medical Center Utrecht, Utrecht, The Netherlands
| | - A de Vos
- Catharina Hospital, Eindhoven, The Netherlands
| | - N van Royen
- Radboud University Medical Center, Nijmegen, The Netherlands
| | - J W Jukema
- Leiden University Medical Center, Leiden, The Netherlands
| | | | | | - P Woudstra
- Medisch Centrum Leeuwarden, Leeuwarden, The Netherlands
| | - T Ten Cate
- Radboud University Medical Center, Nijmegen, The Netherlands
| | - J S Lemkes
- Amsterdam University Medical Centers, Amsterdam, The Netherlands
| | - M A Vink
- Onze Lieve Vrouwe Gasthuis, Amsterdam, The Netherlands
| | - W Balder
- University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - P J Vlaar
- Catharina Hospital, Eindhoven, The Netherlands
| | | | - S Assa
- University Medical Center Groningen, Groningen, The Netherlands
| | - A W van 't Hof
- Maastricht University Medical Center, Maastricht, The Netherlands
| | - J M Ten Berg
- St. Antonius Hospital, Nieuwegein, The Netherlands
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van der Velden YU, Villaudy J, Siteur-van Rijnstra E, van der Linden CA, Vink MA, Schermer EE, Weijer K, Berkhout B, Sanders RW, van Gils MJ. Diverse HIV-1 escape pathways from broadly neutralizing antibody PGDM1400 in humanized mice. MAbs 2020; 12:1845908. [PMID: 33218286 PMCID: PMC7755169 DOI: 10.1080/19420862.2020.1845908] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Recent studies have shown the potential of broadly neutralizing antibodies (bnAbs) for HIV-1 treatment. One of the candidate antibodies moving into clinical trials is the bnAb PGDM1400. Here, we studied the therapeutic potency and escape pathways of bnAb PGDM1400 during monovalent therapy in human immune system (HIS) mice using the BG505, REJO, MJ4 and AMC008 virus isolates. PGDM1400 administered during chronic infection caused a modest decrease in viral load in the first week of administration in 7 out of 10 animals, which correlated with the in vitro neutralization sensitivity of the viruses to PGDM1400. As expected for monotherapy, viral loads rebounded after about a week and different viral escape pathways were observed, involving the deletion of glycans in the envelope glycoprotein at positions 130 or 160. (Pre)clinical trials should reveal whether PGDM1400 is a useful component of an antibody combination treatment or as part of a tri-specific antibody.
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Affiliation(s)
- Yme U van der Velden
- Department of Medical Microbiology, Amsterdam UMC, AMC, University of Amsterdam , Amsterdam, the Netherlands
| | - Julien Villaudy
- Department of Medical Microbiology, Amsterdam UMC, AMC, University of Amsterdam , Amsterdam, the Netherlands.,AIMM Therapeutics , Amsterdam, the Netherlands
| | | | - Cynthia A van der Linden
- Department of Medical Microbiology, Amsterdam UMC, AMC, University of Amsterdam , Amsterdam, the Netherlands.,HIS mouse facility, Amsterdam UMC, AMC, University of Amsterdam , Amsterdam, the Netherlands
| | - Monique A Vink
- Department of Medical Microbiology, Amsterdam UMC, AMC, University of Amsterdam , Amsterdam, the Netherlands
| | - Edith E Schermer
- Department of Medical Microbiology, Amsterdam UMC, AMC, University of Amsterdam , Amsterdam, the Netherlands
| | - Kees Weijer
- HIS mouse facility, Amsterdam UMC, AMC, University of Amsterdam , Amsterdam, the Netherlands
| | - Ben Berkhout
- Department of Medical Microbiology, Amsterdam UMC, AMC, University of Amsterdam , Amsterdam, the Netherlands
| | - Rogier W Sanders
- Department of Medical Microbiology, Amsterdam UMC, AMC, University of Amsterdam , Amsterdam, the Netherlands.,Department of Microbiology and Immunology, Weill Medical College of Cornell University , New York, NY, USA
| | - Marit J van Gils
- Department of Medical Microbiology, Amsterdam UMC, AMC, University of Amsterdam , Amsterdam, the Netherlands
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4
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Tijssen RYG, Van Der Schaaf RJ, Vink MA, Kraak RP, Hofma SH, Arkenbout EK, Weevers APJD, Kerkmeijer LS, Onuma Y, Serruys PWJC, Piek JJ, Tijssen JGP, Henriques JP, De Winter RJ, Wykrzykowska JJ. 126Clinical outcomes at two years of the Absorb BRS vs. the Xience metallic DES in patients presenting with ACS vs. stable coronary disease - AIDA trial substudy. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz747.0042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
AIMS Patients with acute coronary syndrome (ACS) might represent a specific subgroup, in which bioresorbable scaffold implantation in percutaneous coronary intervention, might lead to better outcomes when compared to conventional treatment. ACS patients (STE-ACS patients in particular) are generally younger, and most often have lesions with softer plaques, a lower plaque burden and less extensive coronary artery disease. In this pre-specified subgroup analysis of the AIDA trial, we evaluated the clinical outcomes of Absorb BVS versus Xience EES treated patients presenting with or without ACS.
Methods and results
This analysis includes the 2-year outcomes of all 1845 patients randomized in the AIDA trial subdivided by clinical presentation, a pre-specified subgroup analysis. We compared patients presenting with ACS with those presenting without ACS (ACS versus no-ACS patients). Patients presenting with ACS were further sub-categorized according to the presence or absence of ST-segment elevation at presentation (STE-ACS versus NSTE-ACS patients). Baseline status by clinical presentation was known in all patients, and 842 (45.6%) patients presented with ACS, 456 (25.2%) with STE-ACS and 377 (20.4%) with NSTE-ACS.The rate of the 2-year primary endpoint of target vessel failure (TVF) was similar after treatment with Absorb BVS or Xience EES in ACS patients (10.2% versus 9.0% respectively; p=0.49) and in no-ACS patients (11.7% versus 10.7% respectively; p=0.67) Definite or probable device thrombosis occurred more frequently with Absorb BVS compared to Xience EES in ACS patients (4.3% versus 1.7% respectively, p=0.03) as well as in no-ACS patients (2.4% versus 0.2% respectively; p=0.002). There were no statistically significant interactions between clinical presentation and randomized device modality for TVF (p=0.80) and for the endpoint of definite or probable device thrombosis (p=0.17).
Conclusions
In ACS patients within AIDA, we found no difference in rates of target vessel failure between the Absorb BVS and Xience EES groups. Rates of definite or definite/probable device thrombosis were higher in the Absorb BVS group throughout all clinical presentations. No significant interaction between ACS and no-ACS patients and the occurrence of TVF
Acknowledgement/Funding
The AIDA trial was financially supported by an unrestricted research grant from Abbott Vascular.
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Affiliation(s)
- R Y G Tijssen
- Academic Medical Center of Amsterdam, Amsterdam, Netherlands (The)
| | - R J Van Der Schaaf
- Hospital Onze Lieve Vrouwe Gasthuis, Cardiology, Amsterdam, Netherlands (The)
| | - M A Vink
- Hospital Onze Lieve Vrouwe Gasthuis, Cardiology, Amsterdam, Netherlands (The)
| | - R P Kraak
- Hospital Onze Lieve Vrouwe Gasthuis, Cardiology, Amsterdam, Netherlands (The)
| | - S H Hofma
- Medical Center Leeuwarden, Cardiology, Leeuwarden, Netherlands (The)
| | - E K Arkenbout
- Tergooi Hospital, Cardiology, Blaricum, Netherlands (The)
| | | | - L S Kerkmeijer
- Academic Medical Center of Amsterdam, Amsterdam, Netherlands (The)
| | - Y Onuma
- Erasmus Medical Centre, Rotterdam, Netherlands (The)
| | | | - J J Piek
- Academic Medical Center of Amsterdam, Amsterdam, Netherlands (The)
| | - J G P Tijssen
- Academic Medical Center of Amsterdam, Amsterdam, Netherlands (The)
| | - J P Henriques
- Academic Medical Center of Amsterdam, Amsterdam, Netherlands (The)
| | - R J De Winter
- Academic Medical Center of Amsterdam, Amsterdam, Netherlands (The)
| | - J J Wykrzykowska
- Academic Medical Center of Amsterdam, Amsterdam, Netherlands (The)
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5
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van der Velden YU, Villaudy J, Siteur-van Rijnstra E, van der Linden CA, Frankin E, Weijer K, Schermer E, Vink MA, Berkhout B, Sanders RW, van Gils MJ. Short Communication: Protective Efficacy of Broadly Neutralizing Antibody PGDM1400 Against HIV-1 Challenge in Humanized Mice. AIDS Res Hum Retroviruses 2018; 34:790-793. [PMID: 30003812 DOI: 10.1089/aid.2018.0114] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Broadly neutralizing antibodies (bNAbs) such as PGDM1400 show promise as prophylactic and therapeutic agents against HIV-1. Human immune system mice were passively immunized with different doses of PGDM1400 and challenged 24 h later with a high dose of HIV-1JRCSF. We found that PGDM1400 provided protection against HIV-1 challenge in a concentration dependent manner and that the protective concentration in blood was ∼75-fold higher than the in vitro 50% inhibitory concentration. The results demonstrate that PGDM1400 might be a promising component of strategies to prevent HIV-1 infection and provide support for the pursuit of vaccines that induce PGDM1400-like bNAbs.
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Affiliation(s)
- Yme U. van der Velden
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Julien Villaudy
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
- AIMM Therapeutics, Amsterdam, the Netherlands
| | | | - Cynthia A. van der Linden
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
- HIS Mouse Facility, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Esmay Frankin
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Kees Weijer
- HIS Mouse Facility, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Edith Schermer
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Monique A. Vink
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Ben Berkhout
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
| | - Rogier W. Sanders
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York
| | - Marit J. van Gils
- Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam UMC, University of Amsterdam, Amsterdam, the Netherlands
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6
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Oosterwerff EFJ, Fagel ND, Slagboom T, Tijssen JGP, Herrman JP, Smits PC, Suttorp MJ, Ronner E, Laarman GJ, Patterson MS, Amoroso G, Vink MA, van der Schaaf RJ, Verheugt FWA, Riezebos RK. Impact of percutaneous coronary intervention timing on 5-year outcome in patients with non-ST-segment elevation acute coronary syndromes. The 'wait a day' approach might be safer. Neth Heart J 2016; 24:173-80. [PMID: 26860709 PMCID: PMC4771630 DOI: 10.1007/s12471-016-0803-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Background The OPTIMA trial was a randomised multicentre trial exploring the influence of the timing of percutaneous coronary intervention (PCI) on patient outcomes in an intermediate to high risk non-ST-elevation acute coronary syndrome (NSTE-ACS) population. In order to decide the best treatment strategy for patients presenting with NSTE-ACS, long-term outcomes are essential. Methods Five-year follow-up data from 133 of the 142 patients could be retrieved (94 %). The primary endpoint was a composite of death and spontaneous myocardial infarction (MI). Spontaneous MI was defined as MI occurring more than 30 days after randomisation. Secondary endpoints were the individual outcomes of death, spontaneous MI or re-PCI. Results No significant difference with respect to the primary endpoint was observed (17.8 vs. 10.1 %; HR 1.55, 95 % CI: 0.73–4.22, p = 0.21). There was no significant difference in mortality rate. However, spontaneous MI was significantly more common in the group receiving immediate PCI (11.0 vs. 1.4 %; HR 4.46, 95 % CI: 1.21–16.50, p = 0.02). We did not find a significant difference between the groups with respect to re-PCI rate. Conclusion There was no difference in the composite of death and spontaneous MI. The trial suggests an increased long-term risk of spontaneous MI for patients treated with immediate PCI.
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Affiliation(s)
- Erik F J Oosterwerff
- Heart Centre, Department of Cardiology, Onze Lieve Vrouwe Gasthuis, 1090 HM, PO Box 95500, Amsterdam, The Netherlands.
| | - N D Fagel
- Heart Centre, Department of Cardiology, Onze Lieve Vrouwe Gasthuis, 1090 HM, PO Box 95500, Amsterdam, The Netherlands
| | - T Slagboom
- Heart Centre, Department of Cardiology, Onze Lieve Vrouwe Gasthuis, 1090 HM, PO Box 95500, Amsterdam, The Netherlands
| | - J G P Tijssen
- Heart Centre, Department of Cardiology, Academic Medical Centre, Amsterdam, The Netherlands
| | - J P Herrman
- Heart Centre, Department of Cardiology, Onze Lieve Vrouwe Gasthuis, 1090 HM, PO Box 95500, Amsterdam, The Netherlands
| | - P C Smits
- Heart Centre, Department of Cardiology, Maasstad Hospital, Rotterdam, The Netherlands
| | - M J Suttorp
- Heart Centre, Department of Cardiology, St Antonius Hospital, Nieuwegein, The Netherlands
| | - E Ronner
- Heart Centre, Department of Cardiology, Reinier de Graaf Hospital, Delft, The Netherlands
| | - G J Laarman
- Heart Centre, Department of Cardiology, TweeSteden Hospital, Tilburg, The Netherlands
| | - M S Patterson
- Heart Centre, Department of Cardiology, Onze Lieve Vrouwe Gasthuis, 1090 HM, PO Box 95500, Amsterdam, The Netherlands
| | - G Amoroso
- Heart Centre, Department of Cardiology, Onze Lieve Vrouwe Gasthuis, 1090 HM, PO Box 95500, Amsterdam, The Netherlands
| | - M A Vink
- Heart Centre, Department of Cardiology, Onze Lieve Vrouwe Gasthuis, 1090 HM, PO Box 95500, Amsterdam, The Netherlands
| | - R J van der Schaaf
- Heart Centre, Department of Cardiology, Onze Lieve Vrouwe Gasthuis, 1090 HM, PO Box 95500, Amsterdam, The Netherlands
| | - F W A Verheugt
- Heart Centre, Department of Cardiology, Onze Lieve Vrouwe Gasthuis, 1090 HM, PO Box 95500, Amsterdam, The Netherlands
| | - R K Riezebos
- Heart Centre, Department of Cardiology, Onze Lieve Vrouwe Gasthuis, 1090 HM, PO Box 95500, Amsterdam, The Netherlands
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7
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Das AT, Zhou X, Metz SW, Vink MA, Berkhout B. Selecting the optimal Tet-On system for doxycycline-inducible gene expression in transiently transfected and stably transduced mammalian cells. Biotechnol J 2015; 11:71-9. [PMID: 26333522 DOI: 10.1002/biot.201500236] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 06/14/2015] [Accepted: 09/02/2015] [Indexed: 11/05/2022]
Abstract
The doxycycline (dox)-inducible Tet-On system is widely used to control gene expression in mammalian cells. This system is based on the bacterial Tet operon, which has been modified and improved for its function in eukaryotic cells. To identify the optimal system for different applications, we compared Tet-On variants in frequently used cell types that were either transiently transfected with the relevant plasmids or stably transduced with an "all-in-one" lentiviral vector. The V10 variant performed optimally in the transiently transfected cells and demonstrated no background activity without dox, high dox-induced activity and the highest fold-induction. Because of its very high dox-sensitivity, the V16 system may be preferred if only low intracellular dox concentrations can be reached. V16 performed optimally in the transduced cells and demonstrated the highest activity and dox-sensitivity without background activity. Moreover, V16 demonstrated more robust induction of gene expression after a latency period without dox. This study provides important findings for choosing the optimal Tet-On system for diverse cell culture settings. V10 is the best system for most applications in which the DNA is episomally present in cells, whereas V16 may be optimal when the Tet-On components are stably integrated in the cellular genome.
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Affiliation(s)
- Atze T Das
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
| | - Xue Zhou
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Stefan W Metz
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Monique A Vink
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Ben Berkhout
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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van der Velden GJ, Vink MA, Klaver B, Das AT, Berkhout B. An AUG codon upstream of rev and env open reading frames ensures optimal translation of the simian immunodeficiency virus Env protein. Virology 2012; 436:191-200. [PMID: 23260111 DOI: 10.1016/j.virol.2012.11.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 11/10/2012] [Accepted: 11/18/2012] [Indexed: 11/16/2022]
Abstract
The mRNAs encoding the Rev and Env proteins of simian immunodeficiency virus (SIV) are unique because upstream translation start codons are present that may modulate the expression of these viral proteins. We previously reported the regulatory effect of a small upstream open reading frame (ORF) on Rev and Env translation. Here we study this mechanism in further detail by modulating the strength of the translation signals upstream of the open reading frames in subgenomic reporters. Furthermore, the effects of these mutations on SIV gene expression and viral replication are analyzed. An intricate regulatory mechanism is disclosed that allows the virus to express a balanced amount of these two proteins.
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Affiliation(s)
- Gisela J van der Velden
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
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9
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Abstract
Tat has a pivotal role in human and simian immunodeficiency virus (HIV and SIV) replication because it stimulates transcription by binding to the trans-activator response (TAR) element. In addition, several other Tat functions have been proposed. Most studies have focused on HIV-1 Tat and much less is known about SIV Tat. An SIVmac239 variant was constructed previously in which the Tat-TAR transcription mechanism is functionally replaced by the doxycycline-inducible Tet-On gene expression mechanism (SIV-rtTA). In this study, SIV-rtTA variants were used to analyse the functions of SIV Tat. It was shown that Tat-minus SIV-rtTA variants replicated efficiently in PM1 T-cells, ruling out an additional essential Tat function. Nevertheless, replication was suboptimal in other cells, and evolutionary pressure to repair Tat expression was documented. It was demonstrated that SIV-rtTA required Tat for optimal gene expression, despite the absence of the Tat-TAR axis. This Tat effect was lost upon replacement of the long terminal repeat promoter region by a non-related promoter. These results indicate that Tat can activate SIV transcription via TAR RNA and U3 DNA elements but has no other essential function in replication in cultured cells. The experiments were limited to cell lines and PBMCs, and did not exclude an accessory Tat function under specific conditions or in vivo.
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Affiliation(s)
- Gisela J van der Velden
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, The Netherlands
| | - Monique A Vink
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, The Netherlands
| | - Ben Berkhout
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, The Netherlands
| | - Atze T Das
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, The Netherlands
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10
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Liu YP, Vink MA, Westerink JT, Ramirez de Arellano E, Konstantinova P, Ter Brake O, Berkhout B. Titers of lentiviral vectors encoding shRNAs and miRNAs are reduced by different mechanisms that require distinct repair strategies. RNA 2010; 16:1328-1339. [PMID: 20498457 PMCID: PMC2885682 DOI: 10.1261/rna.1887910] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Accepted: 04/06/2010] [Indexed: 05/29/2023]
Abstract
RNAi-based gene therapy is a powerful approach to treat viral infections because of its high efficiency and sequence specificity. The HIV-1-based lentiviral vector system is suitable for the delivery of RNAi inducers to HIV-1 susceptible cells due to its ability to transduce nondividing cells, including hematopoietic stem cells, and its ability for stable transgene delivery into the host cell genome. However, the presence of anti-HIV short hairpin RNA (shRNA) and microRNA (miRNA) cassettes can negatively affect the lentiviral vector titers. We show that shRNAs, which target the vector genomic RNA, strongly reduced lentiviral vector titers but inhibition of the RNAi pathway via saturation could rescue vector production. The presence of miRNAs in the vector RNA genome (sense orientation) results in a minor titer reduction due to Drosha processing. A major cause for titer reduction of miRNA vectors is due to incompatibility of the cytomegalovirus promoter with the lentiviral vector system. Replacement of this promoter with an inducible promoter resulted in an almost complete restoration of the vector titer. We also showed that antisense poly(A) signal sequences can have a dramatic effect on the vector titer. These results show that not all sequences are compatible with the lentiviral vector system and that care should be taken in the design of lentiviral vectors encoding RNAi inducers.
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Affiliation(s)
- Ying Poi Liu
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam, University of Amsterdam, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands
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11
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Vink MA. [Running, temperature and hydration]. Ned Tijdschr Geneeskd 1988; 132:1307-8. [PMID: 3405333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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