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Lundstrom K. Viral vectors engineered for gene therapy. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2023; 379:1-41. [PMID: 37541721 DOI: 10.1016/bs.ircmb.2023.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/06/2023]
Abstract
Gene therapy has seen major progress in recent years. Viral vectors have made a significant contribution through efficient engineering for improved delivery and safety. A large variety of indications such as cancer, cardiovascular, metabolic, hematological, neurological, muscular, ophthalmological, infectious diseases, and immunodeficiency have been targeted. Viral vectors based on adenoviruses, adeno-associated viruses, herpes simplex viruses, retroviruses including lentiviruses, alphaviruses, flaviviruses, measles viruses, rhabdoviruses, Newcastle disease virus, poxviruses, picornaviruses, reoviruses, and polyomaviruses have been used. Proof-of-concept has been demonstrated for different indications in animal models. Therapeutic efficacy has also been achieved in clinical trials. Several viral vector-based drugs have been approved for the treatment of cancer, and hematological, metabolic, and neurological diseases. Moreover, viral vector-based vaccines have been approved against COVID-19 and Ebola virus disease.
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Treffers EE, Tas A, Scholte FEM, de Ru AH, Snijder EJ, van Veelen PA, van Hemert MJ. The alphavirus nonstructural protein 2 NTPase induces a host translational shut-off through phosphorylation of eEF2 via cAMP-PKA-eEF2K signaling. PLoS Pathog 2023; 19:e1011179. [PMID: 36848386 PMCID: PMC9997916 DOI: 10.1371/journal.ppat.1011179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 03/09/2023] [Accepted: 02/03/2023] [Indexed: 03/01/2023] Open
Abstract
Chikungunya virus (CHIKV) is a reemerging alphavirus. Since 2005, it has infected millions of people during outbreaks in Africa, Asia, and South/Central America. CHIKV replication depends on host cell factors at many levels and is expected to have a profound effect on cellular physiology. To obtain more insight into host responses to infection, stable isotope labeling with amino acids in cell culture and liquid chromatography-tandem mass spectrometry were used to assess temporal changes in the cellular phosphoproteome during CHIKV infection. Among the ~3,000 unique phosphorylation sites analyzed, the largest change in phosphorylation status was measured on residue T56 of eukaryotic elongation factor 2 (eEF2), which showed a >50-fold increase at 8 and 12 h p.i. Infection with other alphaviruses (Semliki Forest, Sindbis and Venezuelan equine encephalitis virus (VEEV)) triggered a similarly strong eEF2 phosphorylation. Expression of a truncated form of CHIKV or VEEV nsP2, containing only the N-terminal and NTPase/helicase domains (nsP2-NTD-Hel), sufficed to induce eEF2 phosphorylation, which could be prevented by mutating key residues in the Walker A and B motifs of the NTPase domain. Alphavirus infection or expression of nsP2-NTD-Hel resulted in decreased cellular ATP levels and increased cAMP levels. This did not occur when catalytically inactive NTPase mutants were expressed. The wild-type nsP2-NTD-Hel inhibited cellular translation independent of the C-terminal nsP2 domain, which was previously implicated in directing the virus-induced host shut-off for Old World alphaviruses. We hypothesize that the alphavirus NTPase activates a cellular adenylyl cyclase resulting in increased cAMP levels, thus activating PKA and subsequently eukaryotic elongation factor 2 kinase. This in turn triggers eEF2 phosphorylation and translational inhibition. We conclude that the nsP2-driven increase of cAMP levels contributes to the alphavirus-induced shut-off of cellular protein synthesis that is shared between Old and New World alphaviruses. MS Data are available via ProteomeXchange with identifier PXD009381.
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Affiliation(s)
- Emmely E. Treffers
- Molecular Virology Laboratory, Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
- Center for Proteomics & Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | - Ali Tas
- Molecular Virology Laboratory, Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Florine E. M. Scholte
- Molecular Virology Laboratory, Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Arnoud H. de Ru
- Center for Proteomics & Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | - Eric J. Snijder
- Molecular Virology Laboratory, Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
| | - Peter A. van Veelen
- Center for Proteomics & Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | - Martijn J. van Hemert
- Molecular Virology Laboratory, Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands
- * E-mail:
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Liu Q, Wu Y, Wang H, Jia F, Xu F. Viral Tools for Neural Circuit Tracing. Neurosci Bull 2022; 38:1508-1518. [PMID: 36136267 PMCID: PMC9723069 DOI: 10.1007/s12264-022-00949-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 06/09/2022] [Indexed: 10/14/2022] Open
Abstract
Neural circuits provide an anatomical basis for functional networks. Therefore, dissecting the structure of neural circuits is essential to understanding how the brain works. Recombinant neurotropic viruses are important tools for neural circuit tracing with many advantages over non-viral tracers: they allow for anterograde, retrograde, and trans-synaptic delivery of tracers in a cell type-specific, circuit-selective manner. In this review, we summarize the recent developments in the viral tools for neural circuit tracing, discuss the key principles of using viral tools in neuroscience research, and highlight innovations for developing and optimizing viral tools for neural circuit tracing across diverse animal species, including nonhuman primates.
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Affiliation(s)
- Qing Liu
- The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Key Laboratory of Viral Vectors for Biomedicine, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, Shenzhen Key Laboratory of Quality Control Technology for Virus-Based Therapeutics, Guangdong Provincial Medical Products Administration, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yang Wu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Huadong Wang
- The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Key Laboratory of Viral Vectors for Biomedicine, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, Shenzhen Key Laboratory of Quality Control Technology for Virus-Based Therapeutics, Guangdong Provincial Medical Products Administration, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Fan Jia
- The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Key Laboratory of Viral Vectors for Biomedicine, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, Shenzhen Key Laboratory of Quality Control Technology for Virus-Based Therapeutics, Guangdong Provincial Medical Products Administration, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Fuqiang Xu
- The Brain Cognition and Brain Disease Institute (BCBDI), Shenzhen Key Laboratory of Viral Vectors for Biomedicine, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen-Hong Kong Institute of Brain Science-Shenzhen Fundamental Research Institutions, NMPA Key Laboratory for Research and Evaluation of Viral Vector Technology in Cell and Gene Therapy Medicinal Products, Shenzhen Key Laboratory of Quality Control Technology for Virus-Based Therapeutics, Guangdong Provincial Medical Products Administration, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Center for Magnetic Resonance, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan, 430071, China.
- Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China.
- University of Chinese Academy of Sciences, Beijing, 100049, China.
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Savar NS, Vallet T, Arashkia A, Lundstrom K, Vignuzzi M, Mahmoudzadeh Niknam H. Packaging, Purification, and Titration of Replication-Deficient Semliki Forest Virus-Derived Particles as a Self-Amplifying mRNA Vaccine Vector. IRANIAN BIOMEDICAL JOURNAL 2022; 26:269-78. [PMID: 35468712 PMCID: PMC9432467 DOI: 10.52547/ibj.3535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 08/23/2022] [Indexed: 12/02/2022]
Abstract
Background Self-amplifying mRNA is the next-generation vaccine platform with the potential advantages in efficacy and speed of development against infectious diseases and cancer. The main aim was to present optimized and rapid methods for Semliki Forest virus (SFV)-PD self-amplifying mRNA (SAM) preparation, its packaging, and titer determination. These protocols are provided for producing and harvesting the high yields of virus replicon particle (VRP)-packaged SAM for vaccine studies. Methods pSFV-PD-EGFP plasmid was linearized and subjected to in vitro transcription. Different concentrations of SFV-PD SAM were first transfected into human embryonic kidney 293 cells (HEK-293) and baby hamster kidney cell line 21 (BHK-21) cell lines, and EGFP expression at different time points was evaluated by fluorescent microscopy. Replicon particle packaging was achieved by co-transfection of SFV-PD SAM and pSFV-Helper2 RNA into BHK-21 cells. The VRPs were concentrated using ultrafiltration with 100 kDa cut-off. The titers of replicon particles were determined by reverse transcription quantitative real-time PCR (RT-qPCR). Results In vitro transcribed SAM encoding EGFP was successfully transfected and expressed in HEK-293 and BHK-21 cell lines. Higher levels of EGFP expression was observed in BHK-21 compared to HEK-293 cells showing more stable protein overexpression and VRP packaging. Using ultrafiltration, the high yields of purified SFV-PD-EGFP particles were rapidly obtained with only minor loss of replicon particles. Accurate and rapid titer determination of replication-deficient particles was achieved by RT-qPCR. Conclusion Using optimized methods for SAM transfection, VRP packaging, and concentration, high yields of SFV-PD VRPs could be produced and purified. The RT-qPCR demonstrated to be an accurate and rapid method for titer determination of replication deficient VRPs.
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Affiliation(s)
| | - Thomas Vallet
- Institut Pasteur, Viral Populations and Pathogenesis Unit, Centre National de la Recherche Scientifique UMR 3569, Paris, France
| | - Arash Arashkia
- Virology Department, Pasteur Institute of Iran, Tehran, Iran
| | | | - Marco Vignuzzi
- Institut Pasteur, Viral Populations and Pathogenesis Unit, Centre National de la Recherche Scientifique UMR 3569, Paris, France
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Savar NS, Shengjuler D, Doroudian F, Vallet T, Mac Kain A, Arashkia A, Khamesipour A, Lundstrom K, Vignuzzi M, Niknam HM. An alphavirus-derived self-amplifying mRNA encoding PpSP15-LmSTI1 fusion protein for the design of a vaccine against leishmaniasis. Parasitol Int 2022; 89:102577. [PMID: 35301120 DOI: 10.1016/j.parint.2022.102577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 02/27/2022] [Accepted: 03/09/2022] [Indexed: 10/18/2022]
Abstract
The main aims of the present study were to design a fusion protein of Leishmania major stress-inducible protein 1 (LmSTI1) and Phlebotomus papatasi SP15 (PpSP15), and to express it in the form of alphavirus packaged Self-amplifying mRNA (SAM). Two combinations, PpSP15-LmSTI1 and LmSTI1-PpSP15 fusion forms, were analyzed for folding and minimum free energies of the mRNA. Conformational studies on 3D modeled fusion and native forms were performed, and the Root-Mean-Square-distance (RMSD) of the Cα atomic coordinates were calculated. Antigenicity and stability were predicted using bioinformatics tools. The coding sequences of PpSP15-LmSTI1 fusion, PpSP15, and LmSTI1 were cloned into an alphavirus-based vector and used to produce the SAM constructs. All the subcloned constructs were then subjected to packaging in the form of viral replicon particles (VRPs),and were evaluated for their ability to infect BHK-21 cells and express the recombinant fusion proteins. The in-silico analysis indicated that the PpSP15-LmSTI1 combination could be a promising candidate based on lower folding ΔG of mRNA, higher protein antigenicity and lower instability indexes, and less conformational changes compared to the native proteins and the LmSTI1-PpSP15 fusion form. Packaged SAM encoding fusion and native antigens are used for infection of mammalian cells and for recombinant protein expression. This is the first study on in silico designing and successful packaging of an alphavirus-derived SAM in the form of the VRPs to target leishmaniasis.
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Affiliation(s)
| | - Djoshkun Shengjuler
- Institut Pasteur, Viral Populations and Pathogenesis Unit, Centre National de la Recherche Scientifique UMR 3569, Paris 75015, France
| | - Fatemeh Doroudian
- Immunology Department, Pasteur Institute of Iran, Tehran 1316943551, Iran
| | - Thomas Vallet
- Institut Pasteur, Viral Populations and Pathogenesis Unit, Centre National de la Recherche Scientifique UMR 3569, Paris 75015, France
| | - Alice Mac Kain
- Institut Pasteur, Viral Populations and Pathogenesis Unit, Centre National de la Recherche Scientifique UMR 3569, Paris 75015, France
| | - Arash Arashkia
- Virology Department, Pasteur Institute of Iran, Tehran 1316943551, Iran
| | - Ali Khamesipour
- Center for Research and Training in Skin Diseases and Leprosy, Tehran University of Medical Sciences, Tehran 1416613675, Iran
| | | | - Marco Vignuzzi
- Institut Pasteur, Viral Populations and Pathogenesis Unit, Centre National de la Recherche Scientifique UMR 3569, Paris 75015, France.
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Maruggi G, Ulmer JB, Rappuoli R, Yu D. Self-amplifying mRNA-Based Vaccine Technology and Its Mode of Action. Curr Top Microbiol Immunol 2022; 440:31-70. [PMID: 33861374 DOI: 10.1007/82_2021_233] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Self-amplifying mRNAs derived from the genomes of positive-strand RNA viruses have recently come into focus as a promising technology platform for vaccine development. Non-virally delivered self-amplifying mRNA vaccines have the potential to be highly versatile, potent, streamlined, scalable, and inexpensive. By amplifying their genome and the antigen encoding mRNA in the host cell, the self-amplifying mRNA mimics a viral infection, resulting in sustained levels of the target protein combined with self-adjuvanting innate immune responses, ultimately leading to potent and long-lasting antigen-specific humoral and cellular immune responses. Moreover, in principle, any eukaryotic sequence could be encoded by self-amplifying mRNA without the need to change the manufacturing process, thereby enabling a much faster and flexible research and development timeline than the current vaccines and hence a quicker response to emerging infectious diseases. This chapter highlights the rapid progress made in using non-virally delivered self-amplifying mRNA-based vaccines against infectious diseases in animal models. We provide an overview of the unique attributes of this vaccine approach, summarize the growing body of work defining its mechanism of action, discuss the current challenges and latest advances, and highlight perspectives about the future of this promising technology.
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Affiliation(s)
| | | | | | - Dong Yu
- GSK, 14200 Shady Grove Road, Rockville, MD, 20850, USA. .,Dynavax Technologies, 2100 Powell Street Suite, Emeryville, CA, 94608, USA.
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Idiotype vaccines produced with a non-cytopathic alphavirus self-amplifying RNA vector induce antitumor responses in a murine model of B-cell lymphoma. Sci Rep 2021; 11:21427. [PMID: 34728659 PMCID: PMC8563967 DOI: 10.1038/s41598-021-00787-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 10/13/2021] [Indexed: 11/08/2022] Open
Abstract
A promising therapy for patients with B-cell lymphoma is based on vaccination with idiotype monoclonal antibodies (mAbs). Since idiotypes are different in each tumor, a personalized vaccine has to be produced for each patient. Expression of immunoglobulins with appropriate post-translational modifications for human use often requires the use of stable mammalian cells that can be scaled-up to reach the desired level of production. We have used a noncytopathic self-amplifying RNA vector derived from Semliki Forest virus (ncSFV) to generate BHK cell lines expressing murine follicular lymphoma-derived idiotype A20 mAb. ncSFV/BHK cell lines expressed approximately 2 mg/L/24 h of A20 mAb with proper quaternary structure and a glycosylation pattern similar to that of A20 mAb produced by hybridoma cells. A20 mAb purified from the supernatant of a ncSFV cell line, or from the hybridoma, was conjugated to keyhole limpet hemocyanin and used to immunize Balb/c mice by administration of four weekly doses of 25 µg of mAb. Both idiotype mAbs were able to induce a similar antitumor protection and longer survival compared to non-immunized mice. These results indicate that the ncSFV RNA vector could represent a quick and efficient system to produce patient-specific idiotypes with potential application as lymphoma vaccines.
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Savar NS, Vallet T, Azizi M, Arashkia A, Lundstrom K, Vignuzzi M, Niknam HM. Quantitative evaluation of PpSP15-LmSTI1 fusion gene expression following transfection with an alphavirus-derived self-amplifying mRNA and conventional DNA vaccine platforms. Mol Cell Probes 2021; 59:101749. [PMID: 34214632 DOI: 10.1016/j.mcp.2021.101749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 06/24/2021] [Accepted: 06/27/2021] [Indexed: 12/28/2022]
Abstract
New vaccine platforms are crucial to address complex parasitic infections such as cutaneous leishmaniasis. Self-amplifying mRNA (SAM) based vaccines represent the next generation nucleic acid-based platform. In the present study, we compared the expression levels of PpSP15-LmSTI1 fusion gene in BHK-21 cells following transfection with Semliki Forest virus (SFV)-derived SAM, SFV-derived plasmid DNA (pSFV-PD) and conventional plasmid DNA (pcDNA3.1+). PpSP15-LmSTI1 fusion gene expression levels were evaluated at different time points, using quantitative Real-time PCR. All data were validated and normalized by two internal control genes. According to the results, mean values of relative expression were significantly higher for SFV-PD SAM/fusion than pcDNA/fusion and pSFV-PD/fusion at all concentrations and time points. Our results showed that higher levels of PpSp15-LmSTI1 antigen expression could be achieved using a SAM vector than pcDNA and pSFV-PD, making it a valuable and efficient alternative to conventional plasmid DNA-based vaccines against leishmaniasis.
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Affiliation(s)
| | - Thomas Vallet
- Institut Pasteur, Viral Populations and Pathogenesis Unit, Centre National de La Recherche Scientifique UMR, 3569, Paris, France
| | - Masoumeh Azizi
- Molecular Medicine Department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran
| | - Arash Arashkia
- Virology Department, Pasteur Institute of Iran, Tehran, Iran
| | | | - Marco Vignuzzi
- Institut Pasteur, Viral Populations and Pathogenesis Unit, Centre National de La Recherche Scientifique UMR, 3569, Paris, France.
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Torres-Ortega PV, Smerdou C, Ansorena E, Ballesteros-Briones MC, Martisova E, Garbayo E, Blanco-Prieto MJ. Optimization of a GDNF production method based on Semliki Forest virus vector. Eur J Pharm Sci 2021; 159:105726. [PMID: 33482318 DOI: 10.1016/j.ejps.2021.105726] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 01/15/2021] [Accepted: 01/15/2021] [Indexed: 11/30/2022]
Abstract
Human glial cell line-derived neurotrophic factor (hGDNF) is the most potent dopaminergic factor described so far, and it is therefore considered a promising drug for Parkinson's disease (PD) treatment. However, the production of therapeutic proteins with a high degree of purity and a specific glycosylation pattern is a major challenge that hinders its commercialization. Although a variety of systems can be used for protein production, only a small number of them are suitable to produce clinical-grade proteins. Specifically, the baby hamster kidney cell line (BHK-21) has shown to be an effective system for the expression of high levels of hGDNF, with appropriate post-translational modifications and protein folding. This system, which is based on the electroporation of BHK-21 cells using a Semliki Forest virus (SFV) as expression vector, induces a strong shut-off of host cell protein synthesis that simplify the purification process. However, SFV vector exhibits a temperature-dependent cytopathic effect on host cells, which could limit hGDNF expression. The aim of this study was to improve the expression and purification of hGDNF using a biphasic temperature cultivation protocol that would decrease the cytopathic effect induced by SFV. Here we show that an increase in the temperature from 33°C to 37°C during the "shut-off period", produced a significant improvement in cell survival and hGDNF expression. In consonance, this protocol led to the production of almost 3-fold more hGDNF when compared to the previously described methods. Therefore, a "recovery period" at 37°C before cells are exposed at 33°C is crucial to maintain cell viability and increase hGDNF expression. The protocol described constitutes an efficient and highly scalable method to produce highly pure hGDNF.
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Affiliation(s)
- Pablo Vicente Torres-Ortega
- Department of Pharmaceutical Technology and Chemistry, Faculty of Pharmacy and Nutrition, Universidad de Navarra, C/ Irunlarrea 1, 31008 Pamplona, Spain; Navarra Institute for Health Research, IdiSNA, C/ Irunlarrea 3, 31008 Pamplona, Spain
| | - Cristian Smerdou
- Navarra Institute for Health Research, IdiSNA, C/ Irunlarrea 3, 31008 Pamplona, Spain; Division of Gene Therapy and Regulation of Gene Expression, Cima Universidad de Navarra, Av. Pío XII 55, 31008, Pamplona, Spain
| | - Eduardo Ansorena
- Navarra Institute for Health Research, IdiSNA, C/ Irunlarrea 3, 31008 Pamplona, Spain; Department of Biochemistry and Genetics, School of Sciences, University of Navarra, Pamplona, Spain
| | - María Cristina Ballesteros-Briones
- Navarra Institute for Health Research, IdiSNA, C/ Irunlarrea 3, 31008 Pamplona, Spain; Division of Gene Therapy and Regulation of Gene Expression, Cima Universidad de Navarra, Av. Pío XII 55, 31008, Pamplona, Spain
| | - Eva Martisova
- Navarra Institute for Health Research, IdiSNA, C/ Irunlarrea 3, 31008 Pamplona, Spain; Division of Gene Therapy and Regulation of Gene Expression, Cima Universidad de Navarra, Av. Pío XII 55, 31008, Pamplona, Spain
| | - Elisa Garbayo
- Department of Pharmaceutical Technology and Chemistry, Faculty of Pharmacy and Nutrition, Universidad de Navarra, C/ Irunlarrea 1, 31008 Pamplona, Spain; Navarra Institute for Health Research, IdiSNA, C/ Irunlarrea 3, 31008 Pamplona, Spain.
| | - María J Blanco-Prieto
- Department of Pharmaceutical Technology and Chemistry, Faculty of Pharmacy and Nutrition, Universidad de Navarra, C/ Irunlarrea 1, 31008 Pamplona, Spain; Navarra Institute for Health Research, IdiSNA, C/ Irunlarrea 3, 31008 Pamplona, Spain.
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Lundstrom K. Impact of a Plasmid DNA-Based Alphavirus Vaccine on Immunization Efficiency. Methods Mol Biol 2021; 2197:33-47. [PMID: 32827131 DOI: 10.1007/978-1-0716-0872-2_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Alphavirus vectors have been engineered for high-level gene expression relying originally on replication-deficient recombinant particles, more recently designed for plasmid DNA-based administration. As alphavirus-based DNA vectors encode the alphavirus RNA replicon genes, enhanced transgene expression in comparison to conventional DNA plasmids is achieved. Immunization studies with alphavirus-based DNA plasmids have elicited specific antibody production, have generated tumor regression and protection against challenges with infectious agents and tumor cells in various animal models. A limited number of clinical trials have been conducted with alphavirus DNA vectors. Compared to conventional plasmid DNA-based immunization, alphavirus DNA vectors required 1000-fold less DNA to elicit similar immune responses in rodents.
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Abstract
Alphavirus-based vectors present an efficient approach for antigen preparation applied for vaccine development. Semliki Forest virus, Sindbis virus, and Venezuelan equine encephalitis virus have been engineered for high-level expression of antigens targeting infectious diseases and tumors. Alphaviruses possess a large application range as vectors can be delivered as naked RNA replicons, recombinant viral particles, and layered DNA plasmids. Immunization studies in animal models have provided protection against challenges with lethal doses of pathogenic infectious agents and tumor cells. So far, a limited number of clinical trials have been conducted for alphavirus vectors in humans.
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Are Viral Vectors Any Good for RNAi Antiviral Therapy? Viruses 2020; 12:v12101189. [PMID: 33092124 PMCID: PMC7589807 DOI: 10.3390/v12101189] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 10/19/2020] [Indexed: 01/20/2023] Open
Abstract
RNA interference (RNAi) represents a novel approach for alternative antiviral therapy. However, issues related to RNA delivery and stability have presented serious obstacles for obtaining good therapeutic efficacy. Viral vectors are capable of efficient delivery of RNAi as short interfering RNA (siRNA), short hairpin RNA (shRNA) and micro-RNA (miRNA). Efficacy in gene silencing for therapeutic applications against viral diseases has been demonstrated in various animal models. Rotavirus (RV) miR-7 can inhibit rotavirus replication by targeting the RV nonstructural protein 5. Viral gene silencing by targeting the RNAi pathway showed efficient suppression of hepatitis B virus replication by adeno-associated virus (AAV)-based delivery of RNAi hepatitis B virus (HBV) cassettes. Hepatitis C virus replication has been targeted by short hairpin RNA molecules expressed from lentivirus vectors. Potentially, RNAi-based approaches could be suitable for antiviral drugs against COVID-19.
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A Trans-amplifying RNA Vaccine Strategy for Induction of Potent Protective Immunity. Mol Ther 2019; 28:119-128. [PMID: 31624015 DOI: 10.1016/j.ymthe.2019.09.009] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 09/03/2019] [Accepted: 09/06/2019] [Indexed: 12/25/2022] Open
Abstract
Here, we present a potent RNA vaccine approach based on a novel bipartite vector system using trans-amplifying RNA (taRNA). The vector cassette encoding the vaccine antigen originates from an alphaviral self-amplifying RNA (saRNA), from which the replicase was deleted to form a transreplicon. Replicase activity is provided in trans by a second molecule, either by a standard saRNA or an optimized non-replicating mRNA (nrRNA). The latter delivered 10- to 100-fold higher transreplicon expression than the former. Moreover, expression driven by the nrRNA-encoded replicase in the taRNA system was as efficient as in a conventional monopartite saRNA system. We show that the superiority of nrRNA- over saRNA-encoded replicase to drive expression of the transreplicon is most likely attributable to its higher translational efficiency and lack of interference with cellular translation. Testing the novel taRNA system in mice, we observed that doses of influenza hemagglutinin antigen-encoding RNA as low as 50 ng were sufficient to induce neutralizing antibodies and mount a protective immune response against live virus challenge. These findings, together with a favorable safety profile, a simpler production process, and the universal applicability associated with this bipartite vector system, warrant further exploration of taRNA.
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Jia F, Zhu X, Lv P, Hu L, Liu Q, Jin S, Xu F. Rapid and Sparse Labeling of Neurons Based on the Mutant Virus-Like Particle of Semliki Forest Virus. Neurosci Bull 2019; 35:378-388. [PMID: 30888608 DOI: 10.1007/s12264-019-00362-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 10/23/2018] [Indexed: 01/08/2023] Open
Abstract
Sparse labeling of neurons contributes to uncovering their morphology, and rapid expression of a fluorescent protein reduces the experiment range. To achieve the goal of rapid and sparse labeling of neurons in vivo, we established a rapid method for depicting the fine structure of neurons at 24 h post-infection based on a mutant virus-like particle of Semliki Forest virus. Approximately 0.014 fluorescent focus-forming units of the mutant virus-like particle transferred enhanced green fluorescent protein into neurons in vivo, and its affinity for neurons in vivo was stronger than for neurons in vitro and BHK21 (baby hamster kidney) cells. Collectively, the mutant virus-like particle provides a robust and convenient way to reveal the fine structure of neurons and is expected to be a helper virus for combining with other tools to determine their connectivity. Our work adds a new tool to the approaches for rapid and sparse labeling of neurons in vivo.
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Affiliation(s)
- Fan Jia
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China.
- Brain Research Center, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China.
- University of the Chinese Academy of Sciences, Beijing, 100049, China.
| | - Xutao Zhu
- Brain Research Center, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China
- University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Pei Lv
- Brain Research Center, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Liang Hu
- Brain Research Center, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Qing Liu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China
- Brain Research Center, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China
| | - Sen Jin
- University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Fuqiang Xu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Key Laboratory of Magnetic Resonance in Biological Systems, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China.
- Brain Research Center, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071, China.
- University of the Chinese Academy of Sciences, Beijing, 100049, China.
- Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai, 200031, China.
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Baltusnikas J, Satkauskas S, Lundstrom K. Constructing RNA Viruses for Long-Term Transcriptional Gene Silencing. Trends Biotechnol 2019; 37:20-28. [DOI: 10.1016/j.tibtech.2018.07.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Revised: 07/19/2018] [Accepted: 07/20/2018] [Indexed: 10/28/2022]
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16
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Wang H, Dewell RB, Ehrengruber MU, Segev E, Reimer J, Roukes ML, Gabbiani F. Optogenetic manipulation of medullary neurons in the locust optic lobe. J Neurophysiol 2018; 120:2049-2058. [PMID: 30110231 PMCID: PMC6230808 DOI: 10.1152/jn.00356.2018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 08/09/2018] [Accepted: 08/09/2018] [Indexed: 11/22/2022] Open
Abstract
The locust is a widely used animal model for studying sensory processing and its relation to behavior. Due to the lack of genomic information, genetic tools to manipulate neural circuits in locusts are not yet available. We examined whether Semliki Forest virus is suitable to mediate exogenous gene expression in neurons of the locust optic lobe. We subcloned a channelrhodopsin variant and the yellow fluorescent protein Venus into a Semliki Forest virus vector and injected the virus into the optic lobe of locusts ( Schistocerca americana). Fluorescence was observed in all injected optic lobes. Most neurons that expressed the recombinant proteins were located in the first two neuropils of the optic lobe, the lamina and medulla. Extracellular recordings demonstrated that laser illumination increased the firing rate of medullary neurons expressing channelrhodopsin. The optogenetic activation of the medullary neurons also triggered excitatory postsynaptic potentials and firing of a postsynaptic, looming-sensitive neuron, the lobula giant movement detector. These results indicate that Semliki Forest virus is efficient at mediating transient exogenous gene expression and provides a tool to manipulate neural circuits in the locust nervous system and likely other insects. NEW & NOTEWORTHY Using Semliki Forest virus, we efficiently delivered channelrhodopsin into neurons of the locust optic lobe. We demonstrate that laser illumination increases the firing of the medullary neurons expressing channelrhodopsin and elicits excitatory postsynaptic potentials and spiking in an identified postsynaptic target neuron, the lobula giant movement detector neuron. This technique allows the manipulation of neuronal activity in locust neural circuits using optogenetics.
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Affiliation(s)
- Hongxia Wang
- Department of Neuroscience, Baylor College of Medicine , Houston, Texas
| | - Richard B Dewell
- Department of Neuroscience, Baylor College of Medicine , Houston, Texas
| | | | - Eran Segev
- Department of Applied Physics and Material Science, California Institute of Technology , Pasadena, California
| | - Jacob Reimer
- Department of Neuroscience, Baylor College of Medicine , Houston, Texas
| | - Michael L Roukes
- Department of Applied Physics and Material Science, California Institute of Technology , Pasadena, California
| | - Fabrizio Gabbiani
- Department of Neuroscience, Baylor College of Medicine , Houston, Texas
- Electrical and Computer Engineering Department, Rice University , Houston, Texas
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17
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Oncolytic Alphaviruses in Cancer Immunotherapy. Vaccines (Basel) 2017; 5:vaccines5020009. [PMID: 28417936 PMCID: PMC5492006 DOI: 10.3390/vaccines5020009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Revised: 04/06/2017] [Accepted: 04/07/2017] [Indexed: 12/12/2022] Open
Abstract
Oncolytic viruses show specific targeting and killing of tumor cells and therefore provide attractive assets for cancer immunotherapy. In parallel to oncolytic viral vectors based on adenoviruses and herpes simplex viruses, oncolytic RNA viruses and particularly alphaviruses have been evaluated as delivery vehicles. Immunization studies in experimental rodent models for various cancers including glioblastoma, hematologic, hepatocellular, colon, cervix, and lung cancer as well as melanoma have been conducted with naturally occurring oncolytic alphavirus strains such as M1 and Sindbis AR339. Moreover, animals were vaccinated with engineered oncolytic replication-deficient and -competent Semliki Forest virus, Sindbis virus and Venezuelan equine encephalitis virus vectors expressing various antigens. Vaccinations elicited strong antibody responses and resulted in tumor growth inhibition, tumor regression and even complete tumor eradication. Vaccination also led to prolonged survival in several animal models. Furthermore, preclinical evaluation demonstrated both prophylactic and therapeutic efficacy of oncolytic alphavirus administration. Clinical trials in humans have mainly been limited to safety studies so far.
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18
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Abstract
Alphavirus-based vectors have been engineered from Semliki Forest virus, Sindbis virus, and Venezuelan equine encephalitis virus and applied for vaccine development. Immunization in preclinical animal models has been conducted with naked RNA replicons, recombinant viral particles and layered DNA-RNA vectors. Most commonly, the targets for the immunization have been viral surface proteins and tumor antigens, which have elicited strong immune responses and even provided protection against challenges with lethal doses of virus and tumor cells, respectively. As alphaviruses also cause epidemics, vaccines have been developed against Chikungunya virus. Despite the success in several animal smodels only a few clinical trials have been conducted in humans, so far.
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19
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Pseudo-typed Semliki Forest virus delivers EGFP into neurons. J Neurovirol 2016; 23:205-215. [PMID: 27739033 DOI: 10.1007/s13365-016-0486-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Revised: 09/22/2016] [Accepted: 09/26/2016] [Indexed: 12/14/2022]
Abstract
Semliki Forest virus (SFV), a neurotropic virus, has been used to deliver heterologous genes into cells in vitro and in vivo. In this study, we constructed a reporter SFV4-FL-EGFP and found that it can deliver EGFP into neurons located at the injection site without disseminating throughout the brain. Lacking of the capsid gene of SFV4-FL-EGFP does not block its life cycle, while forming replication-competent virus-like particles (VLPs). These VLPs hold subviral genome by using the packaging sequence (PS) located within the nsP2 gene, and can transfer their genome into cells. In addition, we found that the G protein of vesicular stomatitis virus (VSVG) can package SFV subviral genome, which is consistent with the previous reports. The G protein of rabies virus (RVG) could also package SFV subviral genome. These pseudo-typed SFV can deliver EGFP gene into neurons. Taken together, these findings may be used to construct various SFV-based delivery systems for virological studies, gene therapy, and neural circuit labeling.
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20
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Schott JW, Morgan M, Galla M, Schambach A. Viral and Synthetic RNA Vector Technologies and Applications. Mol Ther 2016; 24:1513-27. [PMID: 27377044 DOI: 10.1038/mt.2016.143] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 06/30/2016] [Indexed: 12/21/2022] Open
Abstract
Use of RNA is an increasingly popular method to transiently deliver genetic information for cell manipulation in basic research and clinical therapy. In these settings, viral and nonviral RNA platforms are employed for delivery of small interfering RNA and protein-coding mRNA. Technological advances allowing RNA modification for increased stability, improved translation and reduced immunogenicity have led to increased use of nonviral synthetic RNA, which is delivered in naked form or upon formulation. Alternatively, highly efficient viral entry pathways are exploited to transfer genes of interest as RNA incorporated into viral particles. Current viral RNA transfer technologies are derived from Retroviruses, nonsegmented negative-strand RNA viruses or positive-stranded Alpha- and Flaviviruses. In retroviral particles, the genes of interest can either be incorporated directly into the viral RNA genome or as nonviral RNA. Nonsegmented negative-strand virus-, Alpha- and Flavivirus-derived vectors support prolonged expression windows through replication of viral RNA encoding genes of interest. Mixed technologies combining viral and nonviral components are also available. RNA transfer is ideal for all settings that do not require permanent transgene expression and excludes potentially detrimental DNA integration into the target cell genome. Thus, RNA-based technologies are successfully applied for reprogramming, transdifferentiation, gene editing, vaccination, tumor therapy, and gene therapy.
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Affiliation(s)
- Juliane W Schott
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,Cluster of Excellence REBIRTH, Hannover Medical School, Hannover, Germany
| | - Michael Morgan
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,Cluster of Excellence REBIRTH, Hannover Medical School, Hannover, Germany
| | - Melanie Galla
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,Cluster of Excellence REBIRTH, Hannover Medical School, Hannover, Germany
| | - Axel Schambach
- Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany.,Cluster of Excellence REBIRTH, Hannover Medical School, Hannover, Germany.,Division of Hematology/Oncology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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21
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Ehrengruber MU, Lundstrom K. Recombinant Alphavirus-Mediated Expression of Ion Channels and Receptors in the Brain. NEUROMETHODS 2016. [DOI: 10.1007/978-1-4939-3064-7_7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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22
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Abstract
Alphavirus vectors based on Semliki Forest virus, Sindbis virus, and Venezuelan equine encephalitis virus have been widely applied for vaccine development. Naked RNA replicons, recombinant viral particles, and layered DNA vectors have been subjected to immunization in preclinical animal models with antigens for viral targets and tumor antigens. Moreover, a limited number of clinical trials have been conducted in humans. Vaccination with alphavirus vectors has demonstrated efficient immune responses and has showed protection against challenges with lethal doses of virus and tumor cells, respectively. Moreover, vaccines have been developed against alphaviruses causing epidemics such as Chikungunya virus.
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23
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Lundstrom K. Alphavirus vectors as tools in neuroscience and gene therapy. Virus Res 2015; 216:16-25. [PMID: 26307195 DOI: 10.1016/j.virusres.2015.08.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Revised: 08/17/2015] [Accepted: 08/19/2015] [Indexed: 11/30/2022]
Abstract
Alphavirus-based vectors have been engineered for in vitro and in vivo expression of heterelogous genes. The rapid and easy generation of replication-deficient recombinant particles and the broad range of host cell infection have made alphaviruses attractive vehicles for applications in neuroscience and gene therapy. Efficient delivery to primary neurons and hippocampal slices has allowed localization studies of gene expression and electrophysiological recordings of ion channels. Alphavirus vectors have also been applied for in vivo delivery to rodent brain. Due to the strong local transient expression provided by alphavirus vectors a number of immunization and gene therapy approaches have demonstrated both therapeutic and prophylactic efficacy in various animal models.
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24
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Alphaviruses in gene therapy. Viruses 2015; 7:2321-33. [PMID: 25961488 PMCID: PMC4452908 DOI: 10.3390/v7052321] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 04/15/2015] [Accepted: 04/23/2015] [Indexed: 11/18/2022] Open
Abstract
Alphavirus vectors present an attractive approach for gene therapy applications due to the rapid and simple recombinant virus particle production and their broad range of mammalian host cell transduction. Mainly three types of alphavirus vectors, namely naked RNA, recombinant particles and DNA/RNA layered vectors, have been subjected to preclinical studies with the goal of achieving prophylactic or therapeutic efficacy, particularly in oncology. In this context, immunization with alphavirus vectors has provided protection against challenges with tumor cells. Moreover, alphavirus intratumoral and systemic delivery has demonstrated substantial tumor regression and significant prolonged survival rates in various animal tumor models. Recent discoveries of the strong association of RNA interference and disease have accelerated gene therapy based approaches, where alphavirus-based gene delivery can play an important role.
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25
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Mutations conferring a noncytotoxic phenotype on chikungunya virus replicons compromise enzymatic properties of nonstructural protein 2. J Virol 2014; 89:3145-62. [PMID: 25552719 DOI: 10.1128/jvi.03213-14] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Chikungunya virus (CHIKV) (genus Alphavirus) has a positive-sense RNA genome. CHIKV nonstructural protein 2 (nsP2) proteolytically processes the viral nonstructural polyprotein, possesses nucleoside triphosphatase (NTPase), RNA triphosphatase, and RNA helicase activities, and induces cytopathic effects in vertebrate cells. Although alphaviral nsP2 mutations can result in a noncytotoxic phenotype, the effects of such mutations on nsP2 enzymatic activities are not well understood. In this study, we introduced a P718G (PG) mutation and selected for additional mutations in CHIKV nsP2 that resulted in a CHIKV replicon with a noncytotoxic phenotype in BHK-21 cells. Combinations of PG and either an E117K (EK) substitution or a GEEGS sequence insertion after residue T647 (5A) markedly reduced RNA synthesis; however, neither PG nor 5A prevented nsP2 nuclear translocation. Introducing PG into recombinant nsP2 inhibited proteolytic cleavage of nsP1/nsP2 and nsP3/nsP4 sites, reduced GTPase and RNA helicase activities, and abolished RNA stimulation of GTPase activity. 5A and EK modulated the effects of PG. However, only the RNA helicase activity of nsP2 was reduced by both of these mutations, suggesting that defects in this activity may be linked to a noncytotoxic phenotype. These results increase our understanding of the molecular basis for the cytotoxicity that accompanies alphaviral replication. Furthermore, adaptation of the CHIKV replicon containing both 5A and PG allowed the selection of a CHIKV replicon with adaptive mutations in nsP1 and nsP3 that enable persistence in human cell line. Such cell lines represent valuable experimental systems for discovering host factors and for screening inhibitors of CHIKV replication at lower biosafety levels. IMPORTANCE CHIKV is a medically important pathogen that causes febrile illness and can cause chronic arthritis. No approved vaccines or antivirals are available for CHIKV. The attenuation of CHIKV is critical to the establishment of experimental systems that can be used to conduct virus replication studies at a lower biosafety level. We applied a functional selection approach to develop, for the first time, a noncytotoxic CHIKV replicon capable of persisting in human cell lines. We anticipate that this safe and efficient research tool will be valuable for screening CHIKV replication inhibitors and for identifying and analyzing host factors involved in viral replication. We also analyzed, from virological and protein biochemistry perspectives, the functional defects caused by mutations conferring noncytotoxic phenotypes; we found that all known enzymatic activities of CHIKV nsP2, as well as its RNA-binding capability, were compromised by these mutations, which led to a reduced capacity for replication.
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26
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Aranda A, Bezunartea J, Casales E, Rodriguez-Madoz JR, Larrea E, Prieto J, Smerdou C. A quick and efficient method to generate mammalian stable cell lines based on a novel inducible alphavirus DNA/RNA layered system. Cell Mol Life Sci 2014; 71:4637-51. [PMID: 24794511 PMCID: PMC11113970 DOI: 10.1007/s00018-014-1631-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 04/15/2014] [Accepted: 04/17/2014] [Indexed: 01/05/2023]
Abstract
We report a new method to generate high-expressing mammalian cell lines in a quick and efficient way. For that purpose, we developed a master cell line (MCL) containing an inducible alphavirus vector expressing GFP integrated into the genome. In the MCL, recombinant RNA levels increased >4,600-fold after induction, due to a doxycycline-dependent RNA amplification loop. The MCL maintained inducibility and expression during 50 passages, being more efficient for protein expression than a conventional cell line. To generate new cell lines, mutant LoxP sites were inserted into the MCL, allowing transgene and selection gene exchange by Cre-directed recombination, leading to quick generation of inducible cell lines expressing proteins of therapeutic interest, like human cardiotrophin-1 and oncostatin-M at several mg/l/24 h. These proteins contained posttranslational modifications, showed bioactivity, and were efficiently purified. Remarkably, this system allowed production of toxic proteins, like oncostatin-M, since cells able to express it could be grown to the desired amount before induction. These cell lines were easily adapted to growth in suspension, making this methodology very attractive for therapeutic protein production.
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Affiliation(s)
- Alejandro Aranda
- 3P Biopharmaceuticals S.L., Polígono Mocholí, C/Mocholí 2, 31110 Noain, Spain
- Division of Hepatology and Gene Therapy, Center for Applied Medical Research, University of Navarra, Pamplona, Navarra Spain
- Present Address: UFR des Sciences de la Santé Simone Veil, 2 Avenue de la Source de la Bievre, 78180 Montigny-Le-Bretonneux, France
| | - Jaione Bezunartea
- 3P Biopharmaceuticals S.L., Polígono Mocholí, C/Mocholí 2, 31110 Noain, Spain
| | - Erkuden Casales
- Division of Hepatology and Gene Therapy, Center for Applied Medical Research, University of Navarra, Pamplona, Navarra Spain
| | - Juan R. Rodriguez-Madoz
- Division of Hepatology and Gene Therapy, Center for Applied Medical Research, University of Navarra, Pamplona, Navarra Spain
| | - Esther Larrea
- Division of Hepatology and Gene Therapy, Center for Applied Medical Research, University of Navarra, Pamplona, Navarra Spain
| | - Jesus Prieto
- Division of Hepatology and Gene Therapy, Center for Applied Medical Research, University of Navarra, Pamplona, Navarra Spain
- Liver Unit, Clinica Universitaria de Navarra, CIBER-EHD, Pamplona, Spain
| | - Cristian Smerdou
- Division of Hepatology and Gene Therapy, Center for Applied Medical Research, University of Navarra, Pamplona, Navarra Spain
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27
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Gill R, Chang PKY, Prenosil GA, Deane EC, McKinney RA. Blocking brain-derived neurotrophic factor inhibits injury-induced hyperexcitability of hippocampal CA3 neurons. Eur J Neurosci 2013; 38:3554-66. [DOI: 10.1111/ejn.12367] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Revised: 08/16/2013] [Accepted: 08/28/2013] [Indexed: 01/07/2023]
Affiliation(s)
- Raminder Gill
- Department of Pharmacology & Therapeutics; McGill University; Bellini Life Sciences Complex 3649 Promenade Sir William Osler Montreal QC Canada H3G 0B1
| | - Philip K.-Y. Chang
- Department of Pharmacology & Therapeutics; McGill University; Bellini Life Sciences Complex 3649 Promenade Sir William Osler Montreal QC Canada H3G 0B1
| | - George A. Prenosil
- Department of Pharmacology & Therapeutics; McGill University; Bellini Life Sciences Complex 3649 Promenade Sir William Osler Montreal QC Canada H3G 0B1
| | - Emily C. Deane
- Department of Neurology and Neurosurgery; McGill University; Montreal QC Canada
| | - Rebecca A. McKinney
- Department of Pharmacology & Therapeutics; McGill University; Bellini Life Sciences Complex 3649 Promenade Sir William Osler Montreal QC Canada H3G 0B1
- Department of Neurology and Neurosurgery; McGill University; Montreal QC Canada
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28
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Chierzi S, Stachniak TJ, Trudel E, Bourque CW, Murai KK. Activity maintains structural plasticity of mossy fiber terminals in the hippocampus. Mol Cell Neurosci 2012; 50:260-71. [PMID: 22579606 DOI: 10.1016/j.mcn.2012.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 03/14/2012] [Accepted: 05/02/2012] [Indexed: 12/20/2022] Open
Abstract
Neural activity plays an important role in organizing and optimizing neural circuits during development and in the mature nervous system. However, the cellular events that underlie this process still remain to be fully understood. In this study, we investigated the role of neural activity in regulating the structural plasticity of presynaptic terminals in the hippocampal formation. We designed a virus to drive the Drosophila Allatostatin receptor in individual dentate granule neurons to suppress activity of complex mossy fiber terminals 'on-demand' in organotypic slices and used time-lapse confocal imaging to determine the impact on presynaptic remodeling. We found that activity played an important role in maintaining the structural plasticity of the core region of the mossy fiber terminal (MFT) that synapses onto CA3 pyramidal cell thorny excrescences but was not essential for the motility of terminal filopodial extensions that contact local inhibitory neurons. Short-term suppression of activity did not have an impact on the size of the MFT, however, longer-term suppression reduced the overall size of the MFT. Remarkably, global blockade of activity with tetrodotoxin (TTX) interfered with the ability of single cell activity deprivation to slow down terminal dynamics suggesting that differences in activity levels among neighboring synapses promote synaptic remodeling events. The results from our studies indicate that neural activity plays an important role in maintaining structural plasticity of presynaptic compartments in the central nervous system and provide new insight into the time-frame during which activity can affect the morphology of synaptic connections.
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Affiliation(s)
- Sabrina Chierzi
- Centre for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Centre, Montreal General Hospital, Montreal, QC, Canada H3G 1A4
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Wu-yang Z, Guo-dong L. Research on basis of reverse genetics system of a Sindbis-like virus XJ-160. Virol J 2011; 8:519. [PMID: 22082202 PMCID: PMC3245537 DOI: 10.1186/1743-422x-8-519] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Accepted: 11/14/2011] [Indexed: 02/07/2023] Open
Abstract
As a Sindbis-like virus (SINLV), XJ-160 virus was isolated from a pooled sample of Anopheles mosquitoes collected in Xinjiang, China, in 1990. Recombinant plasmid pBR-XJ160 is an infectious full-length cDNA clone of XJ-160 virus, from which rescued virus BR-XJ160 can be obtained by transcription in vitro and transfection. The BR-XJ160 virus raised in BHK-21 cells was indistinguishable from the XJ-160 virus in its biological properties, including its plaque morphology, growth kinetics and suckling mouse neurovirulence. On basis of pBR-XJ160, the effects of substitutions within nonstructural protein 1 (nsP1) or nsP2 on the infectivity and pathogenesis of Sindbis virus (SINV) have been investigated. We have also confirmed the essential role of E2 glycoprotein, especially the domain of 145-150 (amino acid) aa, in SINV infection through the interaction with cellular heparan sulfate (HS). In addition, we have developed XJ-160 virus-based vector system, including replicon vector, defective helper (DH) plasmids and the packaging cell lines (PCLs). Here we provide an update of main development in the field concerned with XJ-160 virus.
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Affiliation(s)
- Zhu Wu-yang
- State Key Laboratory for Infectious Disease Prevention and Control, National Institute for Viral Disease Control and Prevention, Chinese Center for Viral Disease Control and Prevention, Beijing 100052, China.
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30
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Ehrengruber MU, Schlesinger S, Lundstrom K. Alphaviruses: Semliki Forest Virus and Sindbis Virus Vectors for Gene Transfer into Neurons. ACTA ACUST UNITED AC 2011; Chapter 4:Unit 4.22. [DOI: 10.1002/0471142301.ns0422s57] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Sondra Schlesinger
- Department of Molecular Microbiology, Washington University School of Medicine St. Louis Missouri
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31
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Astrocytes display complex and localized calcium responses to single-neuron stimulation in the hippocampus. J Neurosci 2011; 31:8905-19. [PMID: 21677174 DOI: 10.1523/jneurosci.6341-10.2011] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Astrocytes show a complex structural and physiological interplay with neurons and respond to neuronal activation in vitro and in vivo with intracellular calcium elevations. These calcium changes enable astrocytes to modulate synaptic transmission and plasticity through various mechanisms. However, the response pattern of astrocytes to single neuronal depolarization events still remains unresolved. This information is critical for fully understanding the coordinated network of neuron-glial signaling in the brain. To address this, we developed a system to map astrocyte calcium responses along apical dendrites of CA1 pyramidal neurons in hippocampal slices using single-neuron stimulation with channelrhodopsin-2. This technique allowed selective neuronal depolarization without invasive manipulations known to alter calcium levels in astrocytes. Light-evoked neuronal depolarization was elicited and calcium events in surrounding astrocytes were monitored using the calcium-sensitive dye Calcium Orange. Stimulation of single neurons caused calcium responses in populations of astrocytes along the apical axis of CA1 cell dendrites. Calcium responses included single events that were synchronized with neuronal stimulation and poststimulus changes in calcium event frequency, both of which were modulated by glutamatergic and purinergic signaling. Individual astrocytes near CA1 cells showed low ability to respond to repeated neuronal depolarization events. However, the response of the surrounding astrocyte population was remarkably accurate. Interestingly, the reliability of responses was graded with respect to astrocyte location along the CA1 cell dendrite, with astrocytes residing in the primary dendrite subregion being most responsive. This study provides a new perspective on the dynamic response property of astrocyte ensembles to neuronal activity.
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32
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Alphavirus vectors for cancer therapy. Virus Res 2010; 153:179-96. [PMID: 20692305 DOI: 10.1016/j.virusres.2010.07.027] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 07/27/2010] [Accepted: 07/28/2010] [Indexed: 11/23/2022]
Abstract
Alphaviruses contain a single strand RNA genome that can be easily modified to express heterologous genes at very high levels in a broad variety of cells, including tumor cells. Alphavirus vectors can be used as viral particles containing a packaged vector RNA, or directly as nucleic acids in the form of RNA or DNA. In the latter case alphavirus RNA is cloned within a DNA vector downstream of a eukaryotic promoter. Expression mediated by these vectors is generally transient due to the induction of apoptosis. The high expression levels, induction of apoptosis, and activation of type I IFN response are the key features that have made alphavirus vectors very attractive for cancer treatment and vaccination. Alphavirus vectors have been successfully used as vaccines to induce protective and therapeutic immune responses against many tumor-associated antigens in animal models of mastocytoma, melanoma, mammary, prostate, and virally induced tumors. Alphavirus vectors have also shown a high antitumoral efficacy by expressing antitumoral molecules in tumor cells, which include cytokines, antiangiogenic factors or toxic proteins. In these studies induction of apoptosis in tumor cells contributed to the antitumoral efficacy by the release of tumor antigens that can be uptaken by antigen presenting cells, enhancing immune responses against tumors. The potential use of alphaviruses as oncolytic agents has also been evaluated for avirulent strains of Semliki Forest virus and Sindbis virus. The fact that this latter virus has a natural tropism for tumor cells has led to many studies in which this vector was able to reach metastatic tumors when administered systemically. Other "artificial" strategies to increase the tropism of alphavirus for tumors have also been evaluated and will be discussed.
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Corpus callosum: a favorable target for rSFV-mediated gene transfer to rat brain with broad and efficient expression. J Mol Neurosci 2010; 42:255-60. [PMID: 20461495 DOI: 10.1007/s12031-010-9386-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2010] [Accepted: 04/27/2010] [Indexed: 10/19/2022]
Abstract
Recombinant Semliki Forest virus (rSFV), as a new kind of neurotropic vector system, has great potential of gene therapy for stroke. However, very little is known about its transduction characteristics in cerebral cortex or corpus callosum (CC) in vivo, which are common targets for gene transfer in experimental stroke therapy. Here, we investigate and compare rSFV-mediated gene expression at above two brain regions in rat; 2.0 x 10(7) IU of rSFV encoding green fluorescent protein (rSFV-GFP) was locally injected into CC or cerebral cortex in two groups. At 36 h following injection, the number of GFP-positive cells, GFP distribution volume, and GFP expression level were examined in the rat brain of each group using continuous frozen sections and enzyme-linked immunosorbent assay. rSFV vector displayed noticeably different transduction patterns in CC and cerebral cortex in vivo. CC injection of vector increased GFP-positive cell number by 802%, GFP transduction volume by 958%, and GFP expression level by 508% compared with cortical injection (all P < 0.01). We concluded that rSFV CC delivery significantly enhances transduction efficiency in rat brain with its ability to achieve transgene extensive transduction and abundant expression, and CC may be a favorable target for improving rSFV-based gene delivery efficiency to brain.
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Casales E, Aranda A, Quetglas JI, Ruiz-Guillen M, Rodriguez-Madoz JR, Prieto J, Smerdou C. A novel system for the production of high levels of functional human therapeutic proteins in stable cells with a Semliki Forest virus noncytopathic vector. N Biotechnol 2010; 27:138-48. [PMID: 20188220 DOI: 10.1016/j.nbt.2010.02.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2010] [Revised: 02/15/2010] [Accepted: 02/17/2010] [Indexed: 01/18/2023]
Abstract
Semliki Forest virus (SFV) vectors lead to high protein expression in mammalian cells, but expression is transient due to vector cytopathic effects, inhibition of host cell proteins and RNA-based expression. We have used a noncytopathic SFV mutant (ncSFV) RNA vector to generate stable cell lines expressing two human therapeutic proteins: insulin-like growth factor I (IGF-I) and cardiotrophin-1 (CT-1). Therapeutic genes were fused at the carboxy-terminal end of Puromycin N-acetyl-transferase gene by using as a linker the sequence coding for foot-and-mouth disease virus (FMDV) 2A autoprotease. These cassettes were cloned into the ncSFV vector. Recombinant ncSFV vectors allowed rapid and efficient selection of stable BHK cell lines with puromycin. These cells expressed IGF-I and CT-1 in supernatants at levels reaching 1.4 and 8.6 microg/10(6)cells/24 hours, respectively. Two cell lines generated with each vector were passaged ten times during 30 days, showing constant levels of protein expression. Recombinant proteins expressed at different passages were functional by in vitro signaling assays. Stability at RNA level was unexpectedly high, showing a very low mutation rate in the CT-1 sequence, which did not increase at high passages. CT-1 was efficiently purified from supernatants of ncSFV cell lines, obtaining a yield of approximately 2mg/L/24 hours. These results indicate that the ncSFV vector has a great potential for the production of recombinant proteins in mammalian cells.
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Affiliation(s)
- Erkuden Casales
- Center for Applied Medical Research, University of Navarra, Pamplona, Spain
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Barry G, Breakwell L, Fragkoudis R, Attarzadeh-Yazdi G, Rodriguez-Andres J, Kohl A, Fazakerley JK. PKR acts early in infection to suppress Semliki Forest virus production and strongly enhances the type I interferon response. J Gen Virol 2009; 90:1382-1391. [PMID: 19264662 PMCID: PMC2885058 DOI: 10.1099/vir.0.007336-0] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2008] [Accepted: 02/03/2009] [Indexed: 12/20/2022] Open
Abstract
The double-stranded RNA-activated protein kinase (PKR) is a key regulator of protein translation, interferon (IFN) expression and cell survival. Upon infection of vertebrate cells in continuous culture, the alphavirus Semliki Forest virus (SFV) initiates apoptosis and IFN synthesis. To determine the effect of PKR on SFV infection, we studied the course of infection in wild-type (wt) mice, mice with a genetic deletion of PKR (PKR-/-) and mouse embryo fibroblasts (MEFs) derived from these mice. In MEFs, PKR delayed virus protein synthesis, production of infectious virus and caspase-3-activated cell death and reduced the yield of infectious virus by 90%. Small interfering RNA suppression of PKR levels in NIH-3T3 cells also reduced virus production and apoptosis. In MEFs, PKR was not required for initiation of IFN-beta gene transcription, but contributed strongly to the magnitude of this response. Levels of IFN-beta transcripts in PKR-/- MEFs at 8 h were 80% lower than those in wt MEFs and levels of functional IFN at 24 h were 95% lower. Following infection of wt and PKR-/- mice, SFV4 and SFV A7(74) were avirulent. PKR increased levels of serum IFN and the rate of clearance of infectious virus from the brain. In summary, in response to SFV, PKR exerts an early antiviral effect that delays virus protein production and release of infectious virus and, whilst PKR is not required for induction of apoptosis or activation of the type I IFN response, it strongly augments the type I IFN response and contributes to clearance of infectious virus from the mouse brain.
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Affiliation(s)
- Gerald Barry
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - Lucy Breakwell
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - Rennos Fragkoudis
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - Ghassem Attarzadeh-Yazdi
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - Julio Rodriguez-Andres
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - Alain Kohl
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
| | - John K Fazakerley
- The Roslin Institute and Royal School of Veterinary Studies, College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh EH9 1QH, UK
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Lundstrom K. Alphaviruses in gene therapy. Viruses 2009; 1:13-25. [PMID: 21994535 PMCID: PMC3185459 DOI: 10.3390/v1010013] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2009] [Revised: 04/15/2009] [Accepted: 04/20/2009] [Indexed: 11/16/2022] Open
Abstract
Alphaviruses are enveloped single stranded RNA viruses, which as gene therapy vectors provide high-level transient gene expression. Semliki Forest virus (SFV), Sindbis virus (SIN) and Venezuelan Equine Encephalitis (VEE) virus have been engineered as efficient replication-deficient and -competent expression vectors. Alphavirus vectors have frequently been used as vehicles for tumor vaccine generation. Moreover, SFV and SIN vectors have been applied for intratumoral injections in animals implanted with tumor xenografts. SIN vectors have demonstrated natural tumor targeting, which might permit systemic vector administration. Another approach for systemic delivery of SFV has been to encapsulate replication-deficient viral particles in liposomes, which can provide passive targeting to tumors and allow repeated administration without host immune responses. This approach has demonstrated safe delivery of encapsulated SFV particles to melanoma and kidney carcinoma patients in a phase I trial. Finally, the prominent neurotropism of alphaviruses make them attractive for the treatment of CNS-related diseases.
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Zhu WY, Fu SH, Wang JL, He Y, Tang Q, Liang GD. Effects of the nsP2-726 Pro mutation on infectivity and pathogenesis of Sindbis virus derived from a full-length infectious cDNA clone. Virus Res 2009; 142:204-7. [PMID: 19428754 DOI: 10.1016/j.virusres.2009.01.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2008] [Revised: 01/20/2009] [Accepted: 01/26/2009] [Indexed: 11/26/2022]
Abstract
The point mutations at residue 726 Pro in the nonstructural gene 2 (nsP2-726P) could make Sindbis virus (SINV) replicons lacking the structural protein-coding region less cytopathic and capable of persisting in some vertebrate cell lines. However, the effects of nsP2-726P mutations on characteristics of SINV in the context of genomic-RNA are poorly understood. To investigate the effects of point mutations at nsP2-726P on the infectivity and the pathogenesis of SINV, based on the infectious clone (pBR-XJ160) of a Sindbis-like XJ-160 virus, we constructed mutants BR-726L, BR-726S, BR-726V and BR-726A containing point mutations Pro-to-Leu, Pro-to-Ser, Pro-to-Val and Pro-to-Ala. The BR-726V virus and BR-726A virus exhibited similar growth characteristics to the wild-type BR-XJ160 in cultured cells, including cytopathic effects (CPE), plaque morphology and growth kinetics. For the Leu substitution, no CPE or plaques were seen after six passages through BHK-21 cells, although expression of XJ-160 virus-specific protein was detectable by indirect immunofluorescence assay (IFA). The Ser substitutions gave an intermediate phenotype. The mutant viruses exhibited different levels of neurovirulence in 3-day-old suckling mice, which did not match their propagation in cultured cells or in the mouse brain. Compared with BR-XJ160, BR-726A with the Ala substitution showed highly increased neurovirulence, while BR-726V with the Val substitution exhibited an attenuated phenotype. In contrast, BR-726S, with reduced growth capacity in cultured cells and mouse brain, showed intermediate neurovirulence. BR-726L virus produced no lethality or morbidity in suckling mice. Thus, the nsP2-726 Pro residue regulates virus-host cell interactions directly and is also important in viral pathogenesis in suckling mice.
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Affiliation(s)
- Wu-yang Zhu
- State Key Laboratory for Infectious Disease Prevention and Control (SKLID), Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention (IVDC, China CDC), Xuan Wu District, Beijing 100052, China
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Fragkoudis R, Tamberg N, Siu R, Kiiver K, Kohl A, Merits A, Fazakerley JK. Neurons and oligodendrocytes in the mouse brain differ in their ability to replicate Semliki Forest virus. J Neurovirol 2008; 15:57-70. [PMID: 19115134 DOI: 10.1080/13550280802482583] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Semliki Forest virus (SFV) provides an experimental model of acute virus encephalitis and virus-induced demyelinating disease. Two marker viruses expressing fluorescent proteins as part of the replicase or the structural open reading frame were used to evaluate virus replication in cells of the adult mouse brain. Both marker viruses established a high-titer infection in the adult mouse brain. As determined by location, morphology, and immunostaining with neural cell type-specific phenotypic markers, both viruses infected neurons and oligodendrocytes but not astrocytes. Determination of eGFP expression from either the replicase or the structural open-reading frame coupled with immunostaining for either the virus structural protein or the virus nonstructural protein-3 readily distinguished cells at early and late stages of infection. Neurons but not oligodendrocytes rapidly down-regulated virus replication. Rapid down-regulation of virus replication was also observed in mature but not immature primary cultures of rat hippocampal neurons. This study demonstrates for the first time that in vivo central nervous system (CNS) cells differ in their ability to suppress alphavirus replication.
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Affiliation(s)
- Rennos Fragkoudis
- The Roslin Institute and Royal School of Veterinary Studies College of Medicine and Veterinary Medicine, University of Edinburgh, Summerhall, Edinburgh, UK
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Abstract
Alphavirus vectors are high-level, transient expression vectors for therapeutic and prophylactic use. These positive-stranded RNA vectors, derived from Semliki Forest virus, Sindbis virus and Venezuelan equine encephalitis virus, multiply and are expressed in the cytoplasm of most vertebrate cells, including human cells. Part of the genome encoding the structural protein genes, which is amplified during a normal infection, is replaced by a transgene. Three types of vector have been developed: virus-like particles, layered DNA-RNA vectors and replication-competent vectors. Virus-like particles contain replicon RNA that is defective since it contains a cloned gene in place of the structural protein genes, and thus are able to undergo only one cycle of expression. They are produced by transfection of vector RNA, and helper RNAs encoding the structural proteins. Layered DNA-RNA vectors express the Semliki Forest virus replicon from a cDNA copy via a cytomegalovirus promoter. Replication-competent vectors contain a transgene in addition to the structural protein genes. Alphavirus vectors are used for three main applications: vaccine construction, therapy of central nervous system disease, and cancer therapy.
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Salomon SN, Haber M, Murai KK, Dunn RJ. Localization of the Diaphanous-related formin Daam1 to neuronal dendrites. Neurosci Lett 2008; 447:62-7. [PMID: 18832009 DOI: 10.1016/j.neulet.2008.09.051] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Revised: 09/18/2008] [Accepted: 09/19/2008] [Indexed: 11/25/2022]
Abstract
The Rho family of small GTPase proteins are involved in the formation and maintenance of neuronal dendrites. In this study, we show that Daam1, a member of the Diaphanous-related formin protein family and a downstream effector for RhoA, is localized to the dendrites of hippocampal neurons. Immunoblot analysis showed that Daam1 is enriched in the mouse hippocampus and co-fractionates in brain lysates with dendritic and synaptic proteins. Immunohistochemical analysis revealed that Daam1 protein distributes in a punctate pattern throughout the cell body and dendritic shafts of dissociated hippocampal neurons and organotypic hippocampal cultures. Although Daam1 is mostly expressed in the shaft of dendrites, co-stainings with SV2 or PSD95 revealed that Daam1 is also present at some synapses. In addition, viral directed expression of a fluorescently tagged Daam1 fusion protein in hippocampal slices resulted in targeted delivery to the dendrites of pyramidal neurons, leading to a reduction in the density of spines.
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Affiliation(s)
- Steven N Salomon
- Center for Research in Neuroscience, McGill University Health Centre Research Institute, McGill University, Montreal, Quebec, Canada
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41
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Zhang XH, Liu F, Chen Q, Zhang CL, Zhuo M, Xiong ZQ, Li BM. Conditioning-strength dependent involvement of NMDA NR2B subtype receptor in the basolateral nucleus of amygdala in acquisition of auditory fear memory. Neuropharmacology 2008; 55:238-46. [DOI: 10.1016/j.neuropharm.2008.05.030] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2008] [Revised: 05/20/2008] [Accepted: 05/20/2008] [Indexed: 11/29/2022]
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42
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Ehrengruber MU, Lundstrom K. Alphaviruses: Semliki Forest virus and Sindbis virus vectors for gene transfer into neurons. ACTA ACUST UNITED AC 2008; Chapter 4:Unit 4.22. [PMID: 18428656 DOI: 10.1002/0471142301.ns0422s41] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Alphaviral vectors based on Semliki Forest virus and Sindbis virus infect many host cell types, causing rapid and high-level transgene expression. Compared to other viruses used to infect CNS cell and tissue preparations, Semliki Forest virus and Sindbis virus exhibit an outstanding preference for neurons rather than glial cells. High-titer vector generation typically requires biosafety level 1 or 2 containment and occurs in less than 2 days. Wild-type vectors are cytotoxic, permitting short-term transgene expression. However, mutant vectors with decreased cytotoxicity, to prolong host cell survival, have been developed. They also increase transgene expression and cellular coinfection, permitting heteromeric protein expression in individual cells. Other mutants with temperature-dependent control of transgene expression and altered host cell preference to target interneurons and astrocytes rather than principal neurons are available. Because of these advantages, alphaviral vectors are increasingly used in neurobiological and other studies, including structural biology, vaccine development, and cancer treatment.
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Casales E, Rodriguez-Madoz JR, Ruiz-Guillen M, Razquin N, Cuevas Y, Prieto J, Smerdou C. Development of a new noncytopathic Semliki Forest virus vector providing high expression levels and stability. Virology 2008; 376:242-51. [PMID: 18442838 DOI: 10.1016/j.virol.2008.03.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2008] [Revised: 03/18/2008] [Accepted: 03/18/2008] [Indexed: 10/22/2022]
Abstract
Alphavirus vectors express high levels of recombinant proteins in mammalian cells, but their cytopathic nature makes this expression transient. In order to generate a Semliki Forest virus (SFV) noncytopathic vector we introduced mutations previously described to turn Sindbis virus noncytopathic into a conserved position in an SFV vector expressing LacZ. Interestingly, mutant P718T in replicase nsp2 subunit was able to replicate in only a small percentage of BHK cells, producing beta-gal-expressing colonies without selection. Puromycin N-acetyl-transferase (pac) gene was used to replace LacZ in this mutant allowing selection of an SFV noncytopathic replicon containing a second mutation in nsp2 nuclear localization signal (R649H). This latter mutation did not confer a noncytopathic phenotype by itself and did not alter nsp2 nuclear translocation. Replicase synthesis was diminished in the SFV double mutant, leading to genomic and subgenomic RNA levels that were 125-fold and 66-fold lower than in wild-type vector, respectively. Interestingly, this mutant expressed beta-gal levels similar to parental vector. By coexpressing pac and LacZ from independent subgenomic promoters this vector was able to generate stable cell lines maintaining high expression levels during at least 10 passages, indicating that it could be used as a powerful system for protein production in mammalian cells.
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Affiliation(s)
- Erkuden Casales
- Division of Gene Therapy, School of Medicine, Center for Applied Medical Research (CIMA),University of Navarra, Av. Pio XII 55, 31008 Pamplona, Spain
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Tamm K, Merits A, Sarand I. Mutations in the nuclear localization signal of nsP2 influencing RNA synthesis, protein expression and cytotoxicity of Semliki Forest virus. J Gen Virol 2008; 89:676-686. [PMID: 18272758 PMCID: PMC2275301 DOI: 10.1099/vir.0.83320-0] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The cytotoxicity of Semliki Forest virus (SFV) infection is caused partly by the non-structural protein nsP2, an essential component of the SFV replicase complex. Due to the presence of a nuclear localization signal (NLS), nsP2 also localizes in the nucleus of infected cells. The present study analysed recombinant SFV replicons and genomes with various deletions or substitutions in the NLS, or with a proline-to-glycine mutation at position 718 of nsP2 (P718G). Deletion of one or two arginine residues from the NLS or substitution of two of the arginines with aspartic acid resulted in a virus with a temperature-sensitive phenotype, and substitution of all three arginines was lethal. Thus, most of the introduced mutations severely affected nsP2 functioning in viral replication; in addition, they inhibited the ability of SFV to induce translational shut-off and kill infected cells. SFV replicons with a P718G mutation or replacement of the NLS residues 648RRR650 with RDD were found to be the least cytotoxic. Corresponding replicons expressed non-structural proteins at normal levels, but had severely reduced genomic RNA synthesis and were virtually unable to replicate and transcribe co-electroporated helper RNA. The non-cytotoxic phenotype was maintained in SFV full-length genomes harbouring the corresponding mutations; however, during a single cycle of cell culture, these were converted to a cytotoxic phenotype, probably due to the accumulation of compensatory mutations.
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Affiliation(s)
- Kristi Tamm
- Estonian Biocentre, Riia 23, 51010, Tartu, Estonia
| | - Andres Merits
- Institute of Technology, University of Tartu, Nooruse 1, 50411, Tartu, Estonia.,Estonian Biocentre, Riia 23, 51010, Tartu, Estonia
| | - Inga Sarand
- Estonian Biocentre, Riia 23, 51010, Tartu, Estonia
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Kiiver K, Merits A, Sarand I. Novel vectors expressing anti-apoptotic protein Bcl-2 to study cell death in Semliki Forest virus-infected cells. Virus Res 2007; 131:54-64. [PMID: 17904678 PMCID: PMC2194287 DOI: 10.1016/j.virusres.2007.08.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2007] [Revised: 08/04/2007] [Accepted: 08/20/2007] [Indexed: 11/24/2022]
Abstract
Semliki Forest virus (SFV, Alphavirus) induce rapid shut down of host cell protein synthesis and apoptotic death of infected vertebrate cells. Data on alphavirus-induced apoptosis are controversial. In this study, the anti-apoptotic bcl-2 gene was placed under the control of duplicated subgenomic promoter or different internal ribosome entry sites (IRES) and expressed using a novel bicistronic SFV vector. The use of IRES containing vectors resulted in high-level Bcl-2 synthesis during the early stages of infection. Nevertheless, in infected BHK-21 cells translational shutdown was almost complete by 6h post-infection, which was similar to infection with appropriate control vectors. These results indicate that very early and high-level bcl-2 expression did not have a protective effect against SFV induced shutdown of host cell translation. No apoptotic cells were detected at those time points for any SFV vectors. Furthermore, Bcl-2 expression did not protect BHK-21 or AT3-neo cells at later time points, and infection of BHK-21 or AT3-neo cells with SFV replicon vectors or with wild-type SFV4 did not lead to release of cytochrome c from mitochondria. Taken together, our data suggest that SFV induced death in BHK-21 or AT3-neo cells is not triggered by the intrinsic pathway of apoptosis.
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Affiliation(s)
- Kaja Kiiver
- Estonian Biocentre, Riia Street 23, 51010 Tartu, Estonia
- Institute of Molecular and Cell Biology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
| | - Andres Merits
- Estonian Biocentre, Riia Street 23, 51010 Tartu, Estonia
- Institute of Molecular and Cell Biology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
- Corresponding author at: Institute of Molecular and Cell Biology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia. Tel.: +372 7374881; fax: +372 7374900.
| | - Inga Sarand
- Estonian Biocentre, Riia Street 23, 51010 Tartu, Estonia
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Ehrengruber MU, Goldin AL. Semliki Forest virus vectors with mutations in the nonstructural protein 2 gene permit extended superinfection of neuronal and non-neuronal cells. J Neurovirol 2007; 13:353-63. [PMID: 17849319 DOI: 10.1080/13550280701393204] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Semliki Forest virus (SFV) vectors are widely used in neurobiological studies because they efficiently infect neurons. As with any viral vector, they possess a limited cloning capacity, so infection with different SFV vectors may be required to introduce multiple transgenes into individual cells. However, this approach is limited by superinfection exclusion. The authors examined marker expression in baby hamster kidney cells, mouse cortical neurons, and rat hippocampal neurons using different fluorophore-encoding vectors that are based on the wild-type SFV4 strain and on the less cytopathic SFV4(PD) mutant, which carries two point mutations in nonstructural protein 2. For every fluorophore tested, SFV4(PD) gave higher (up to 22-fold) expression compared to SFV4. In infections using two and three different vectors, SFV4 caused relatively few multifluorescent baby hamster kidney cells when applied at 0-s, 15-min, or 2-h intervals. In contrast, SFV4(PD) permitted significantly enhanced marker coexpression, resulting in 46% doubly and 21% triply fluorescent baby hamster kidney cells, and 67% to 8% doubly fluorescent cortical and hippocampal neurons. At 15-min or 2-h addition intervals, SFV4(PD) still permitted 23% to 36% doubly fluorescent baby hamster kidney cells. The increased efficiency of SFV4(PD) in coexpressing separate markers from different viral particles suggests that mutations in nonstructural protein 2 affect alphaviral superinfection exclusion. The results demonstrate that SFV4(PD) is well-suited to coexpress multiple proteins in neuronal and non-neuronal cells. This capability is particularly valuable to express the various components of heteromeric protein complexes, especially when the individual cDNAs cannot be combined into single SFV particles.
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Affiliation(s)
- Markus U Ehrengruber
- Department of Microbiology and Molecular Genetics, University of California, Irvine, California, USA.
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Taoufik E, Valable S, Müller GJ, Roberts ML, Divoux D, Tinel A, Voulgari-Kokota A, Tseveleki V, Altruda F, Lassmann H, Petit E, Probert L. FLIP(L) protects neurons against in vivo ischemia and in vitro glucose deprivation-induced cell death. J Neurosci 2007; 27:6633-46. [PMID: 17581950 PMCID: PMC6672692 DOI: 10.1523/jneurosci.1091-07.2007] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Knowledge of the molecular mechanisms that underlie neuron death after stroke is important to allow the development of effective neuroprotective strategies. In this study, we investigated the contribution of death receptor signaling pathways to neuronal death after ischemia using in vitro and in vivo models of ischemic injury and transgenic mice that are deficient in tumor necrosis factor receptor I (TNFRI KO) or show neuron-specific overexpression of the long isoform of cellular Fas-associated death domain-like interleukin-1-beta-converting enzyme-inhibitory protein (FLIP(L)). Caspase 8 was activated in brain lesions after permanent middle cerebral artery occlusion (pMCAO) and in cortical neurons subjected to glucose deprivation (GD) and was necessary for GD-induced neuron death. Thus, neurons treated with zIETD-FMK peptide or overexpressing a dominant-negative caspase 8 mutant were fully protected against GD-induced death. The presence of the neuroprotective TNFRI was necessary for selectively sustaining p50/p65NF-kappaB activity and the expression of the p43 cleavage form of FLIP(L), FLIP(p43), an endogenous inhibitor of caspase 8, in pMCAO lesions and GD-treated neurons. Moreover, TNF pretreatment further upregulated p50/p65NF-kappaB activity and FLIP(p43) expression in neurons after GD. The knock-down of FLIP in wild-type (WT) neurons using a short hairpin RNA revealed that FLIP(L) is essential for TNF/TNFRI-mediated neuroprotection after GD. Furthermore, the overexpression of FLIP(L) was sufficient to rescue TNFRI KO neurons from GD-induced death and to enhance TNF neuroprotection in WT neurons, and neuron-specific expression of FLIP(L) in transgenic mice significantly reduced lesion volume after pMCAO. Our results identify a novel role for the TNFRI-NF-kappaB-FLIP(L) pathway in neuroprotection after ischemia and identify potential new targets for stroke therapy.
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Affiliation(s)
- Era Taoufik
- Laboratory of Molecular Genetics, Hellenic Pasteur Institute, 11521 Athens, Greece
| | - Samuel Valable
- Universite de Caen, Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6185, 14074 Caen, France
| | - Georg J. Müller
- Division of Neuroimmunology, Brain Research Institute, A-1090 Vienna, Austria
| | | | - Didier Divoux
- Universite de Caen, Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6185, 14074 Caen, France
| | - Antoine Tinel
- Institute of Biochemistry, University of Lausanne, CH-1066 Epalinges, Switzerland, and
| | - Anda Voulgari-Kokota
- Laboratory of Molecular Genetics, Hellenic Pasteur Institute, 11521 Athens, Greece
| | - Vivian Tseveleki
- Laboratory of Molecular Genetics, Hellenic Pasteur Institute, 11521 Athens, Greece
| | - Fiorella Altruda
- Dipartimento di Genetica, Biologia e Biochimica, Universita di Torino, 10126 Torino, Italy
| | - Hans Lassmann
- Division of Neuroimmunology, Brain Research Institute, A-1090 Vienna, Austria
| | - Edwige Petit
- Universite de Caen, Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6185, 14074 Caen, France
| | - Lesley Probert
- Laboratory of Molecular Genetics, Hellenic Pasteur Institute, 11521 Athens, Greece
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48
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Abstract
This protocol describes a method for making and culturing rat hippocampal organotypic slices on membrane inserts. Supplementary videos are included to demonstrate visually the different steps of the procedure. Cultured hippocampal slices has been increasingly used as a model for synaptic studies of the brain as they allow examination of mid to long term manipulations in a preparation where the gross cytoarchitecture of the hippocampus is preserved. Combining techniques such as molecular biology, electrophysiology and immunohistochemistry to study physiological or pathological processes can easily be applied to organotypic slices. The technique described here can be used to make organotypic slices from other parts of the brain, other rodent species and from a range of ages. This protocol can be completed in 3 h.
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Affiliation(s)
- Anna De Simoni
- Department of Physiology, University College London, Gower Street, London WCIE 6BT, UK.
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49
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Zhou L, Martinez SJ, Haber M, Jones EV, Bouvier D, Doucet G, Corera AT, Fon EA, Zisch AH, Murai KK. EphA4 signaling regulates phospholipase Cgamma1 activation, cofilin membrane association, and dendritic spine morphology. J Neurosci 2007; 27:5127-38. [PMID: 17494698 PMCID: PMC6672384 DOI: 10.1523/jneurosci.1170-07.2007] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Specialized postsynaptic structures known as dendritic spines are the primary sites of glutamatergic innervation at synapses of the CNS. Previous studies have shown that spines rapidly remodel their actin cytoskeleton to modify their shape and this has been associated with changes in synaptic physiology. However, the receptors and signaling intermediates that restructure the actin network in spines are only beginning to be identified. We reported previously that the EphA4 receptor tyrosine kinase regulates spine morphology. However, the signaling pathways downstream of EphA4 that induce spine retraction on ephrin ligand binding remain poorly understood. Here, we demonstrate that ephrin stimulation of EphA4 leads to the recruitment and activation of phospholipase Cgamma1 (PLCgamma1) in heterologous cells and in hippocampal slices. This interaction occurs through an Src homology 2 domain of PLCgamma1 and requires the EphA4 juxtamembrane tyrosines. In the brain, PLCgamma1 is found in multiple compartments of synaptosomes and is readily found in postsynaptic density fractions. Consistent with this, PLC activity is required for the maintenance of spine morphology and ephrin-induced spine retraction. Remarkably, EphA4 and PLC activity modulate the association of the actin depolymerizing/severing factor cofilin with the plasma membrane. Because cofilin has been implicated previously in the structural plasticity of spines, this signaling may enable cofilin to depolymerize actin filaments and restructure spines at sites of ephrin-EphA4 contact.
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Affiliation(s)
- Lei Zhou
- Center for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Center, Montreal General Hospital, Montreal, Quebec, Canada H3G 1A4
| | - Sarah J. Martinez
- Center for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Center, Montreal General Hospital, Montreal, Quebec, Canada H3G 1A4
| | - Michael Haber
- Center for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Center, Montreal General Hospital, Montreal, Quebec, Canada H3G 1A4
| | - Emma V. Jones
- Center for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Center, Montreal General Hospital, Montreal, Quebec, Canada H3G 1A4
| | - David Bouvier
- Département de Pathologie et Biologie Cellulaire and Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada H3C 3J7
| | - Guy Doucet
- Département de Pathologie et Biologie Cellulaire and Groupe de Recherche sur le Système Nerveux Central, Université de Montréal, Montréal, Québec, Canada H3C 3J7
| | - Amadou T. Corera
- Center for Neuronal Survival and Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada H3A 3B4
| | - Edward A. Fon
- Center for Neuronal Survival and Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada H3A 3B4
| | - Andreas H. Zisch
- Department of Obstetrics, University Hospital Zurich, 8091 Zurich, Switzerland, and
- Center for Integrative Human Physiology, University of Zurich, 8091 Zurich, Switzerland
| | - Keith K. Murai
- Center for Research in Neuroscience, Department of Neurology and Neurosurgery, The Research Institute of the McGill University Health Center, Montreal General Hospital, Montreal, Quebec, Canada H3G 1A4
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50
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Chen Q, He S, Hu XL, Yu J, Zhou Y, Zheng J, Zhang S, Zhang C, Duan WH, Xiong ZQ. Differential roles of NR2A- and NR2B-containing NMDA receptors in activity-dependent brain-derived neurotrophic factor gene regulation and limbic epileptogenesis. J Neurosci 2007; 27:542-52. [PMID: 17234586 PMCID: PMC6672795 DOI: 10.1523/jneurosci.3607-06.2007] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Fleeting activation of NMDA receptors (NMDARs) induces long-term modification of synaptic connections and refinement of neuronal circuits, which may underlie learning and memory and contribute to pathogenesis of a diversity of neurological diseases, including epilepsy. Here, we found that NR2A and NR2B subunit-containing NMDARs were coupled to distinct intracellular signaling, resulting in differential BDNF expression and extracellular signal-regulated kinase 1/2 (ERK1/2) activation. Selective activation of NR2A-containing NMDARs increased BDNF gene expression. Activation of NR2B-containing NMDARs led to ERK1/2 phosphorylation. Furthermore, selectively blocking NR2A-containing NMDARs impaired epileptogenesis and the development of mossy fiber sprouting in the kindling and pilocarpine rat models of limbic epilepsy, whereas inhibiting NR2B-containing NMDARs had no effects in epileptogenesis and mossy fiber sprouting. Interestingly, blocking either NR2A- or NR2B-containing NMDARs decreased status epilepticus-induced neuronal cell death. The specific requirement of NR2A and its downstream signaling for epileptogenesis implicates attractive new targets for the development of drugs that prevent epilepsy in patients with brain injury.
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Affiliation(s)
- Qian Chen
- Institute of Neuroscience and Key Laboratory of Neurobiology and
- Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China
| | - Songtao He
- Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China, and
- Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China
| | - Xiao-Ling Hu
- Institute of Neuroscience and Key Laboratory of Neurobiology and
- Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China
| | - Jing Yu
- Institute of Neuroscience and Key Laboratory of Neurobiology and
| | - Yang Zhou
- Institute of Neuroscience and Key Laboratory of Neurobiology and
- Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China
| | - Jing Zheng
- Institute of Neuroscience and Key Laboratory of Neurobiology and
- Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China
| | - Shilei Zhang
- Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China, and
- Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China
| | - Chi Zhang
- Institute of Neuroscience and Key Laboratory of Neurobiology and
| | - Wen-Hu Duan
- Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China, and
- Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China
| | - Zhi-Qi Xiong
- Institute of Neuroscience and Key Laboratory of Neurobiology and
- Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China
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