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Ahmadivand S, Krpetic Z, Martínez MM, Garcia-Ordoñez M, Roher N, Palić D. Self-assembling ferritin nanoplatform for the development of infectious hematopoietic necrosis virus vaccine. Front Immunol 2024; 15:1346512. [PMID: 38352881 PMCID: PMC10863052 DOI: 10.3389/fimmu.2024.1346512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 01/09/2024] [Indexed: 02/16/2024] Open
Abstract
Self-assembling protein nanoparticles are used as a novel vaccine design platform to improve the stability and immunogenicity of safe subunit vaccines, while providing broader protection against viral infections. Infectious Hematopoietic Necrosis virus (IHNV) is the causative agent of the WOAH-listed IHN diseases for which there are currently no therapeutic treatments and no globally available commercial vaccine. In this study, by genetically fusing the virus glycoprotein to the H. pylori ferritin as a scaffold, we constructed a self-assembling IHNV nanovaccine (FerritVac). Despite the introduction of an exogenous fragment, the FerritVac NPs show excellent stability same as Ferritin NPs under different storage, pH, and temperature conditions, mimicking the harsh gastrointestinal condition of the virus main host (trout). MTT viability assays showed no cytotoxicity of FerritVac or Ferritin NPs in zebrafish cell culture (ZFL cells) incubated with different doses of up to 100 µg/mL for 14 hours. FerritVac NPs also upregulated expression of innate antiviral immunity, IHNV, and other fish rhabdovirus infection gene markers (mx, vig1, ifit5, and isg-15) in the macrophage cells of the host. In this study, we demonstrate the development of a soluble recombinant glycoprotein of IHNV in the E. coli system using the ferritin self-assembling nanoplatform, as a biocompatible, stable, and effective foundation to rescue and produce soluble protein and enable oral administration and antiviral induction for development of a complete IHNV vaccine. This self-assembling protein nanocages as novel vaccine approach offers significant commercial potential for non-mammalian and enveloped viruses.
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Affiliation(s)
- Sohrab Ahmadivand
- Faculty of Veterinary Medicine, Ludwig-Maximilians University Munich, Munich, Germany
| | - Zeljka Krpetic
- Biomedical Research Centre, School of Science Engineering and Environment, University of Salford, Salford, United Kingdom
| | - Merce Márquez Martínez
- Institute of Biotechnology and Biomedicine (IBB), Universitat Autònoma de Barcelona, Barcelona, Spain
- CIBER de Bioingeniería Biomateriales y Nanomedicina (CIBER-BBN), Barcelona, Spain
| | - Marlid Garcia-Ordoñez
- Institute of Biotechnology and Biomedicine (IBB), Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Nerea Roher
- Institute of Biotechnology and Biomedicine (IBB), Universitat Autònoma de Barcelona, Barcelona, Spain
- CIBER de Bioingeniería Biomateriales y Nanomedicina (CIBER-BBN), Barcelona, Spain
| | - Dušan Palić
- Faculty of Veterinary Medicine, Ludwig-Maximilians University Munich, Munich, Germany
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Tang X, Ma X, Cao J, Sheng X, Xing J, Chi H, Zhan W. The Influence of Temperature on the Antiviral Response of mIgM+ B Lymphocytes Against Hirame Novirhabdovirus in Flounder (Paralichthys olivaceus). Front Immunol 2022; 13:802638. [PMID: 35197977 PMCID: PMC8858815 DOI: 10.3389/fimmu.2022.802638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 01/17/2022] [Indexed: 11/20/2022] Open
Abstract
Hirame novirhabdovirus (HIRRV) is an ongoing threat to the aquaculture industry. The water temperature for the onset of HIRRV is below 15°C, the peak is about 10°C, but no mortality is observed over 20°C. Previous studies found the positive signal of matrix protein of HIRRV (HIRRV-M) was detected in the peripheral blood leukocytes of viral-infected flounder. Flow cytometry and indirect immunofluorescence assay showed that HIRRV-M was detected in mIgM+ B lymphocytes in viral-infected flounder maintained at 10°C and 20°C, and 22% mIgM+ B lymphocytes are infected at 10°C while 13% are infected at 20°C, indicating that HIRRV could invade into mIgM+ B lymphocytes. Absolute quantitative RT-PCR showed that the viral copies in mIgM+ B lymphocytes were significantly increased at 24 h post infection (hpi) both at 10°C and 20°C, but the viral copies in 10°C infection group were significantly higher than that in 20°C infection group at 72 hpi and 96 hpi. Furthermore, the B lymphocytes were sorted from HIRRV-infected flounder maintained at 10°C and 20°C for RNA-seq. The results showed that the differentially expression genes in mIgM+ B lymphocyte of healthy flounder at 10°C and 20°C were mainly enriched in metabolic pathways. Lipid metabolism and Amino acid metabolism were enhanced at 10°C, while Glucose metabolism was enhanced at 20°C. In contrast, HIRRV infection at 10°C induced the up-regulation of the Complement and coagulation cascades, FcγR-mediated phagocytosis, Platelets activation, Leukocyte transendothelial migration and Natural killer cell mediated cytotoxicity pathways at 72 hpi. HIRRV infection at 20°C induced the up-regulation of the Antigen processing and presentation pathway at 72 hpi. Subsequently, the temporal expression patterns of 16 genes involved in Antigen processing and presentation pathway were investigated by qRT-PCR, and results showed that the pathway was significantly activated by HIRRV infection at 20°C but inhibited at 10°C. In conclusion, HIRRV could invade into mIgM+ B lymphocytes and elicit differential immune response under 10°C and 20°C, which provide a deep insight into the antiviral response in mIgM+ B lymphocytes.
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Affiliation(s)
- Xiaoqian Tang
- Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Xinbiao Ma
- Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Jing Cao
- Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Xiuzhen Sheng
- Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Jing Xing
- Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
| | - Heng Chi
- Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao, China
| | - Wenbin Zhan
- Laboratory of Pathology and Immunology of Aquatic Animals, Key Laboratory of Mariculture, Ministry of Education (KLMME), Ocean University of China, Qingdao, China
- Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- *Correspondence: Wenbin Zhan,
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Ma J, Wang H, Zheng X, Wu H, Yang S, Xia X. Western equine encephalitis virus virus-like particles from an insect cell-baculovirus system elicit the strong immune responses in mice. Biotechnol J 2021; 16:e2100008. [PMID: 34176228 DOI: 10.1002/biot.202100008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 06/18/2021] [Accepted: 06/21/2021] [Indexed: 11/07/2022]
Abstract
Western equine encephalitis virus (WEEV) causes lethal encephalitis in humans and equines, and it poses a serious public health threat in many countries. Therefore, the development of an efficient vaccine remains an important challenge for the prevention of WEEV infection. This study presents the first description of WEEV virus-like particles (VLPs) generated from insect cells using recombinant baculoviruses. WEEV VLPs with 206 adjuvant could trigger a strong cellular immune response; increase the levels of IL-2, IL-4 and IFN-γ; and induce a high level of neutralizing antibodies against WEEV in mice. These data showed that the insect cell-baculovirus system is suitable for the production of WEEV VLPs and that these VLPs could elicit the strong immunogenicity in mice. These results suggest a new, nonreplicating, and effective vaccine candidate against WEEV infection.
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Affiliation(s)
- JinZhu Ma
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, Jilin, China.,College of Life Science and Biotechnology, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang, China
| | - HuaLei Wang
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, Jilin, China
| | - XueXing Zheng
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, Jilin, China
| | - HongXia Wu
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, Jilin, China
| | - SongTao Yang
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, Jilin, China
| | - XianZhu Xia
- Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Changchun Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Changchun, Jilin, China
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Wang H, Tang X, Sheng X, Xing J, Chi H, Zhan W. Transcriptome analysis reveals temperature-dependent early immune response in flounder (Paralichthys olivaceus) after Hirame novirhabdovirus (HIRRV) infection. FISH & SHELLFISH IMMUNOLOGY 2020; 107:367-378. [PMID: 33091595 DOI: 10.1016/j.fsi.2020.10.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 10/13/2020] [Accepted: 10/18/2020] [Indexed: 06/11/2023]
Abstract
Hirame novirhabdovirus (HIRRV), as a highly pathogenic fish virus, is frequently prevalent in a variety of aquaculture fish in recent years, which seriously threatens the healthy development of aquaculture industry. Epidemiological studies show that the outbreak of HIRRV is obviously temperature dependent. Virus proliferation experiments in vitro and in vivo at different temperatures indicate the antiviral response of flounder is a main reason affect the replication of HIRRV. The RNA-Seq was used to analyze the different antiviral response in flounder which infected with HIRRV at different temperatures, the experiment set two temperatures of 10 °C and 20 °C. The flounder infected with HIRRV by artificial injection, and the spleens were collected at 24 h after infection. Meanwhile, the fish injected with EPC supernatant at different temperatures were set as control groups. It can obtain four pairwise comparison groups if determine a single variable, and the differentially expressed genes were further selected. The results showed that after infection with HIRRV at 10 °C and 20 °C, the differentially expressed genes in spleen were significantly enriched in inflammatory and immune-related pathways like Arachidonic acid metabolism, Cytokine-cytokine receptor interaction, Toll-like receptor (TLR) signaling pathway, RIG-I-like receptor (RLRs) signaling pathway, NOD-like receptor (NLR) signaling pathway and Cytosolic DNA-sensing pathway etc. In addition, the expression of phagocytes, lysosomes, endocytosis related genes were significantly upregulated at high temperature whether HIRRV positive or not. But compared to the infected flounder at 10 °C, some genes of RLRs signaling pathway were significantly upregulated at 20 °C, it can be speculated that RLRs pathway may be related to the anti-HIRRV response of flounder. Therefore, key genes of RLRs signaling pathway including mda5, lgp2, mita, mavs, irf3, irf7, ifn I-3 and ifn-γ were selected, and the temporal expression patterns of these genes in infected flounder at different temperatures were further detected by qRT-PCR. The results showed that HIRRV infection can significantly stimulate and activate the RLRs pathway of flounder, and the response level of this pathway was significantly higher at 20 °C than 10 °C. In general, this study provides important data for the further study about the pathogenesis of HIRRV infection in flounder.
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Affiliation(s)
- Hongxiang Wang
- Laboratory of Pathology and Immunology of Aquatic Animals, KLMME, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China
| | - Xiaoqian Tang
- Laboratory of Pathology and Immunology of Aquatic Animals, KLMME, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China.
| | - Xiuzhen Sheng
- Laboratory of Pathology and Immunology of Aquatic Animals, KLMME, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
| | - Jing Xing
- Laboratory of Pathology and Immunology of Aquatic Animals, KLMME, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
| | - Heng Chi
- Laboratory of Pathology and Immunology of Aquatic Animals, KLMME, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China
| | - Wenbin Zhan
- Laboratory of Pathology and Immunology of Aquatic Animals, KLMME, Ocean University of China, 5 Yushan Road, Qingdao, 266003, China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266071, China
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5
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Jeong KH, Kim HJ, Kim HJ. Current status and future directions of fish vaccines employing virus-like particles. FISH & SHELLFISH IMMUNOLOGY 2020; 100:49-57. [PMID: 32130976 DOI: 10.1016/j.fsi.2020.02.060] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 02/25/2020] [Accepted: 02/27/2020] [Indexed: 05/15/2023]
Abstract
In most breeding schemes, fish are cultured in enclosed spaces, which greatly increases the risk of outbreaks where the onset of infectious diseases can cause massive mortality and enormous economic losses. Vaccination is the most effective and long-term measure for improving the basic make-up of a fish farm. As the relationship between antibody and antigen is similar to that between screw and nut, similarity in the shape or nature of the vaccine antigen to the original pathogen is important for achieving a satisfactory/good/excellent antibody response with a vaccine. Virus-like particles (VLPs) best fulfil this requirement as their tertiary structure mimics that of the native virus. For this reason, VLPs have been attracting attention as next-generation vaccines for humans and animals, and the effects of various types of VLP vaccines on humans and livestock have been examined. Recent studies of VLP-based fish vaccines indicate that these vaccines are promising, and raise hopes of extending their use in the near future. In this review, the structural properties and immunogenicity of VLP-based vaccines against fish viruses such as infectious pancreatic necrosis virus (IPNV), salmonid alphavirus (SAV), nervous necrosis virus (NNV) and iridovirus are introduced/summarized. The NNV VLP vaccine is the most-studied VLP-based vaccine against fish viruses. Therefore, the current status of NNV VLP research is highlighted in this review, which deals with the advantages of using VLPs as vaccines, and the expression systems for producing them. Moreover, the need for lyophilized VLPs and oral VLP delivery is discussed. Finally, future directions for the development of VLP vaccines in the fish vaccine field are considered.
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Affiliation(s)
- Ki-Ho Jeong
- Laboratory of Virology, College of Pharmacy, Chung-Ang University, 84 Heukseok-Ro, Dongjak-Gu, Seoul, 06974, South Korea
| | - Hyoung Jin Kim
- Laboratory of Virology, College of Pharmacy, Chung-Ang University, 84 Heukseok-Ro, Dongjak-Gu, Seoul, 06974, South Korea
| | - Hong-Jin Kim
- Laboratory of Virology, College of Pharmacy, Chung-Ang University, 84 Heukseok-Ro, Dongjak-Gu, Seoul, 06974, South Korea.
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6
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Collet B, Collins C, Lester K. Engineered cell lines for fish health research. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2018; 80:34-40. [PMID: 28108246 DOI: 10.1016/j.dci.2017.01.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Revised: 01/13/2017] [Accepted: 01/16/2017] [Indexed: 06/06/2023]
Abstract
As fish farming continues to increase worldwide, the related research areas of fish disease and immunology are also expanding, aided by the revolution in access to genomic information and molecular technology. The genomes of most fish species of economic importance are now available and annotation based on sequence homology with characterised genomes is underway. However, while useful, functional homology is more difficult to determine, there being a lack of widely distributed and well characterised reagents such as monoclonal antibodies, traditionally used in mammalian studies, to help with confirming functions and cellular interactions of fish molecules. In this context, fish cell lines and the possibility of their genetic engineering offer good prospects for studying functional genomics with respect to fish diseases. In this review, we will give an overview of available permanently genetically engineered fish cell lines, as cell-based reporter systems or platforms for expression of endogenous immune or pathogen genes, to investigate interactions and function. The advantages of such systems and the technical challenge for their development will be discussed.
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7
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Chang CJ, Gu J, Robertsen B. Protective effect and antibody response of DNA vaccine against salmonid alphavirus 3 (SAV3) in Atlantic salmon. JOURNAL OF FISH DISEASES 2017; 40:1775-1781. [PMID: 28493514 DOI: 10.1111/jfd.12644] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 03/10/2017] [Accepted: 03/14/2017] [Indexed: 05/13/2023]
Abstract
This work reports the effect of two DNA vaccines against salmonid alphavirus 3 (SAV3) in Atlantic salmon. Presmolts were vaccinated by intramuscular injection of plasmids encoding the SAV3 structural polyprotein C-E3-E2-6K-E2 (pCSP), E2 only (pE2), or plasmid without insert (pcDNA3.3). E2 is expressed at the surface of cells transfected with pCSP and internally in cells transfected with pE2. A commercial vaccine based on inactivated SAV (NCPD) was used for comparison. At 10 weeks post-vaccination, only fish vaccinated with pCSP showed antibody against E2 and virus-neutralizing activity. Vaccinated fish were infected with SAV3 to determine protection by virus quantitation in serum after 7 days and scoring of pathological changes after 21 days. Fish vaccinated with both pCSP and NCPD vaccines showed significant virus reduction in serum, while fish vaccinated with pE2 did not. All fish vaccinated with pcDNA3.3 and pE2 showed pathological changes in organs typical of PD, 60% of fish vaccinated with NCPD showed PD pathology, while fish vaccinated with pCSP did not show PD pathology. Taken together, DNA vaccination with pCSP provided strong protection for salmon against SAV3 infection, which in part may be due to production of virus-neutralizing antibodies.
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Affiliation(s)
- C J Chang
- Norwegian College of Fishery Science, UiT The Arctic University of Norway, Tromsø, Norway
| | - J Gu
- Norwegian Veterinary Institute, Trondheim, Norway
| | - B Robertsen
- Norwegian College of Fishery Science, UiT The Arctic University of Norway, Tromsø, Norway
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Ramsey J, Mukhopadhyay S. Disentangling the Frames, the State of Research on the Alphavirus 6K and TF Proteins. Viruses 2017; 9:v9080228. [PMID: 28820485 PMCID: PMC5580485 DOI: 10.3390/v9080228] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2017] [Revised: 08/03/2017] [Accepted: 08/16/2017] [Indexed: 01/04/2023] Open
Abstract
For 30 years it was thought the alphavirus 6K gene encoded a single 6 kDa protein. However, through a bioinformatics search 10 years ago, it was discovered that there is a frameshifting event and two proteins, 6K and transframe (TF), are translated from the 6K gene. Thus, many functions attributed to the 6K protein needed reevaluation to determine if they properly belong to 6K, TF, or both proteins. In this mini-review, we reevaluate the past research on 6K and put those results in context where there are two proteins, 6K and TF, instead of one. Additionally, we discuss the most cogent outstanding questions for 6K and TF research, including their collective importance in alphavirus budding and their potential importance in disease based on the latest virulence data.
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Affiliation(s)
- Jolene Ramsey
- Department of Biology at Indiana University, Bloomington, IN 47405, USA.
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Fourrier MCS, Collet B. Production of infectious salmon anaemia virus (ISAV) ribonucleoprotein complexes using a mammalian cell based minigenome system. J Virol Methods 2016; 239:75-82. [PMID: 27840076 DOI: 10.1016/j.jviromet.2016.10.017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Accepted: 10/30/2016] [Indexed: 11/28/2022]
Abstract
Developments in recombinant virus techniques have been crucial to understand the mechanisms of virulence acquisition and study the replication of many different negatively stranded RNA viruses. However, such technology has been lacking for infectious salmon anaemia virus (ISAV) until recently. This was due in part to the lack of a Polymerase I promoter in Atlantic salmon to drive the production of recombinant vRNA. Therefore, the present study investigated a different alternative to produce ISAV recombinant vRNA, based on Mouse Pol I promoter/terminator sequences and expression in baby hamster kidney (BHK-21) cells. As a first step, a pathogenic ISAV was demonstrated to replicate and produce viable virions in BHK-21 cells. This indicated that the virus could use the mammalian cellular and nuclear machinery to produce vRNA segments and viral proteins, albeit in a limited capacity. Co-transfection of vRNA expressing plasmids with cytomegalovirus (CMV) promoter constructs coding for the three viral polymerase and nucleoprotein led to the generation of functional ribonucleoproteins (RNPs) which expressed either, green fluorescence protein (GFP) or firefly luciferase (FF). Further experiments demonstrated that a 21h incubation at 37°C was optimal for RNPs production. Inhibition by ribavirin confirmed that FF expression was linked to specific RNPs polymerase transcription. The present minigenome system provides a novel and alternative approach to investigate various aspects of ISAV replication and potentially those of other negatively stranded RNA viruses. Expression of RNPs in mammalian cells could also provide a method for the rapid screening of anti-viral compounds targeting ISAV replication.
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Affiliation(s)
| | - Bertrand Collet
- Marine Scotland Science, Marine Laboratory, AB11 9DB, Aberdeen, United Kingdom.
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Shirbaghaee Z, Bolhassani A. Different applications of virus-like particles in biology and medicine: Vaccination and delivery systems. Biopolymers 2016; 105:113-32. [PMID: 26509554 PMCID: PMC7161881 DOI: 10.1002/bip.22759] [Citation(s) in RCA: 95] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Revised: 10/25/2015] [Accepted: 10/25/2015] [Indexed: 12/17/2022]
Abstract
Virus-like particles (VLPs) mimic the whole construct of virus particles devoid of viral genome as used in subunit vaccine design. VLPs can elicit efficient protective immunity as direct immunogens compared to soluble antigens co-administered with adjuvants in several booster injections. Up to now, several prokaryotic and eukaryotic systems such as insect, yeast, plant, and E. coli were used to express recombinant proteins, especially for VLP production. Recent studies are also generating VLPs in plants using different transient expression vectors for edible vaccines. VLPs and viral particles have been applied for different functions such as gene therapy, vaccination, nanotechnology, and diagnostics. Herein, we describe VLP production in different systems as well as its applications in biology and medicine.
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Affiliation(s)
- Zeinab Shirbaghaee
- Department of Hepatitis and AIDSPasteur Institute of IranTehranIran
- Department of Immunology, School of Public HealthTehran University of Medical SciencesTehranIran
| | - Azam Bolhassani
- Department of Hepatitis and AIDSPasteur Institute of IranTehranIran
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11
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Herath TK, Ferguson HW, Weidmann MW, Bron JE, Thompson KD, Adams A, Muir KF, Richards RH. Pathogenesis of experimental salmonid alphavirus infection in vivo: an ultrastructural insight. Vet Res 2016; 47:7. [PMID: 26743442 PMCID: PMC4705579 DOI: 10.1186/s13567-015-0300-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 05/23/2015] [Indexed: 12/27/2022] Open
Abstract
Salmonid alphavirus (SAV) is an enveloped, single-stranded,
positive sense RNA virus belonging to the family Togaviridae. It causes economically devastating disease in cultured salmonids. The characteristic features of SAV infection include severe histopathological changes in the heart, pancreas and skeletal muscles of diseased fish. Although the presence of virus has been reported in a wider range of tissues, the mechanisms responsible for viral tissue tropism and for lesion development during the disease are not clearly described or understood. Previously, we have described membrane-dependent morphogenesis of SAV and associated apoptosis-mediated cell death in vitro. The aims of the present study were to explore ultrastructural changes associated with SAV infection in vivo. Cytolytic changes were observed in heart, but not in gill and head-kidney of virus-infected fish, although they still exhibited signs of SAV morphogenesis. Ultrastructural changes associated with virus replication were also noted in leukocytes in the head kidney of virus-infected fish. These results further describe the presence of degenerative lesions in the heart as expected, but not in the gills and in the kidney.
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Affiliation(s)
- Tharangani K Herath
- Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling, UK.
| | - Hugh W Ferguson
- School of Veterinary Medicine, St George's University, St. George, Grenada, West Indies.
| | - Manfred W Weidmann
- Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling, UK.
| | - James E Bron
- Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling, UK.
| | - Kimberly D Thompson
- Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling, UK. .,Moredun Research Institute, Pentlands Science Park, Bush Loan Penicuik, Edinburgh, UK.
| | - Alexandra Adams
- Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling, UK.
| | - Katherine F Muir
- Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling, UK.
| | - Randolph H Richards
- Institute of Aquaculture, School of Natural Sciences, University of Stirling, Stirling, UK.
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12
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Hikke MC, Geertsema C, Wu V, Metz SW, van Lent JW, Vlak JM, Pijlman GP. Alphavirus capsid proteins self-assemble into core-like particles in insect cells: A promising platform for nanoparticle vaccine development. Biotechnol J 2015; 11:266-73. [PMID: 26287127 DOI: 10.1002/biot.201500147] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 06/18/2015] [Accepted: 08/13/2015] [Indexed: 11/07/2022]
Abstract
The mosquito-borne chikungunya virus (CHIKV) causes arthritic diseases in humans, whereas the aquatic salmonid alphavirus (SAV) is associated with high mortality in aquaculture of salmon and trout. Using modern biotechnological approaches, promising vaccine candidates based upon highly immunogenic, enveloped virus-like particles (eVLPs) have been developed. However, the eVLP structure (core, lipid membrane, surface glycoproteins) is more complex than that of non-enveloped, protein-only VLPs, which are structurally and morphologically 'simple'. In order to develop an alternative to alphavirus eVLPs, in this paper we engineered recombinant baculovirus vectors to produce high levels of alphavirus core-like particles (CLPs) in insect cells by expression of the CHIKV and SAV capsid proteins. The CLPs localize in dense nuclear bodies within the infected cell nucleus and are purified through a rapid and scalable protocol involving cell lysis, sonication and low-speed centrifugation steps. Furthermore, an immunogenic epitope from the alphavirus E2 glycoprotein can be successfully fused to the N-terminus of the capsid protein without disrupting the CLP self-assembling properties. We propose that immunogenic epitope-tagged alphavirus CLPs produced in insect cells present a simple and perhaps more stable alternative to alphavirus eVLPs.
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Affiliation(s)
- Mia C Hikke
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands
| | - Corinne Geertsema
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands
| | - Vincen Wu
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands
| | - Stefan W Metz
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands
| | - Jan W van Lent
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands
| | - Just M Vlak
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands
| | - Gorben P Pijlman
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands.
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13
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Pijlman GP. Enveloped virus-like particles as vaccines against pathogenic arboviruses. Biotechnol J 2015; 10:659-70. [DOI: 10.1002/biot.201400427] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 11/27/2014] [Accepted: 12/22/2014] [Indexed: 12/26/2022]
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14
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van Oers MM, Pijlman GP, Vlak JM. Thirty years of baculovirus–insect cell protein expression: from dark horse to mainstream technology. J Gen Virol 2015; 96:6-23. [DOI: 10.1099/vir.0.067108-0] [Citation(s) in RCA: 216] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
- Monique M. van Oers
- Laboratory of Virology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Gorben P. Pijlman
- Laboratory of Virology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
| | - Just M. Vlak
- Laboratory of Virology, Wageningen University, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
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15
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Hikke MC, Braaen S, Villoing S, Hodneland K, Geertsema C, Verhagen L, Frost P, Vlak JM, Rimstad E, Pijlman GP. Salmonid alphavirus glycoprotein E2 requires low temperature and E1 for virion formation and induction of protective immunity. Vaccine 2014; 32:6206-12. [DOI: 10.1016/j.vaccine.2014.09.026] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 09/09/2014] [Accepted: 09/10/2014] [Indexed: 10/24/2022]
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16
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Valero Y, García-Alcázar A, Esteban MÁ, Cuesta A, Chaves-Pozo E. Seasonal variations of the humoral immune parameters of European sea bass (Dicentrarchus labrax L.). FISH & SHELLFISH IMMUNOLOGY 2014; 39:185-187. [PMID: 24852342 DOI: 10.1016/j.fsi.2014.05.011] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Revised: 04/30/2014] [Accepted: 05/12/2014] [Indexed: 06/03/2023]
Abstract
Seasonal cycles, mainly due to great variations in the light duration and temperature, are important and modulate several aspects of the animal behavior. In the case of poikilotherms animals such as fish this is very relevant. Thus, temperature changes fish immunity and affects disease resistance. We evaluate in this work the season variations of the European sea bass (Dicentrarchus labrax) humoral innate parameters focusing on winter months, at which the culture of this specie is more difficult. Our results showed that not all the innate immune parameters are depressed by low temperatures. Moreover, some of them are more dependent than others to the season and both temperature and photoperiod are operating together.
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Affiliation(s)
- Yulema Valero
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n., Puerto de Mazarrón, 30860 Murcia, Spain
| | - Alicia García-Alcázar
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n., Puerto de Mazarrón, 30860 Murcia, Spain
| | - M Ángeles Esteban
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain
| | - Alberto Cuesta
- Fish Innate Immune System Group, Department of Cell Biology and Histology, Faculty of Biology, Campus Regional de Excelencia Internacional "Campus Mare Nostrum", University of Murcia, 30100 Murcia, Spain
| | - Elena Chaves-Pozo
- Centro Oceanográfico de Murcia, Instituto Español de Oceanografía (IEO), Carretera de la Azohía s/n., Puerto de Mazarrón, 30860 Murcia, Spain.
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17
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Hikke MC, Verest M, Vlak JM, Pijlman GP. Salmonid alphavirus replication in mosquito cells: towards a novel vaccine production system. Microb Biotechnol 2014; 7:480-4. [PMID: 24418177 PMCID: PMC4229328 DOI: 10.1111/1751-7915.12100] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2013] [Revised: 10/14/2013] [Accepted: 10/21/2013] [Indexed: 11/28/2022] Open
Abstract
Salmonid alphavirus (SAV) causes pancreas disease and sleeping disease in Atlantic salmon (Salmosalar) and rainbow trout (Oncorhynchus mykiss) and confers a major burden to the aquaculture industry. A commercial inactivated whole virus vaccine propagated in a salmon cell line at low temperature provides effective protection against SAV infections. Alphaviruses (family Togaviridae) are generally transmitted between vertebrate hosts via blood-sucking arthropod vectors, typically mosquitoes. SAV is unique in this respect because it can be transmitted directly from fish to fish and has no known invertebrate vector. Here, we show for the first time that SAV is able to complete a full infectious cycle within arthropod cells derived from the Asian tiger mosquito Aedes albopictus. Progeny virus is produced in C6/36 and U4.4. cells in a temperature-dependent manner (at 15°C but not at 18°C), can be serially passaged and remains infectious to salmonid Chinook salmon embryo cells. This suggests that SAV is not a vertebrate-restricted alphavirus after all and may have the potential to replicate in invertebrates. The current study also shows the ability of SAV to be propagated in mosquito cells, thereby possibly providing an alternative SAV production system for vaccine applications.
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Affiliation(s)
- Mia C Hikke
- Wageningen University, Laboratory of Virology, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
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18
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Olsen CM, Pemula AK, Braaen S, Sankaran K, Rimstad E. Salmonid alphavirus replicon is functional in fish, mammalian and insect cells and in vivo in shrimps (Litopenaeus vannamei). Vaccine 2013; 31:5672-9. [DOI: 10.1016/j.vaccine.2013.09.058] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 09/18/2013] [Accepted: 09/24/2013] [Indexed: 10/26/2022]
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19
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High production of recombinant Norwegian salmonid alphavirus E1 and E2 proteins in Escherichia coli by fusion to secretion signal sequences and removal of hydrophobic domains. BIOTECHNOL BIOPROC E 2013. [DOI: 10.1007/s12257-013-0085-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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20
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Liu F, Wu X, Li L, Ge S, Liu Z, Wang Z. Virus-like particles: promising platforms with characteristics of DIVA for veterinary vaccine design. Comp Immunol Microbiol Infect Dis 2013; 36:343-52. [PMID: 23561290 DOI: 10.1016/j.cimid.2013.02.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2012] [Revised: 02/13/2013] [Accepted: 02/25/2013] [Indexed: 11/27/2022]
Abstract
In general, it is difficult to differentiate infected from vaccinated animals through vaccination with conventional vaccines, thereby impeding the serological surveillance of animal diseases. DIVA (differentiating infected from vaccinated animals) vaccine, originally known as marker vaccine, usually based on the absence of at least one immunogenic protein in the vaccine strain, allows DIVA in conjunction with a diagnostic test that detects antibodies against the antigens lacking in the vaccine strain. Virus-like particles (VLPs), composed of one or more structural proteins but no genomes of native viruses, mimic the organization and conformation of authentic virions but have no ability to self-replicate in cells, potentially yielding safer vaccine candidates. Since VLPs containing either monovalent or multivalent antigen can be produced in compliance with the requirements for serological surveillance, the use of VLP-based vaccines plays a promising role in DIVA vaccination strategies against animal diseases. Here, we critically reviewed VLPs and companion diagnostics with properties of DIVA for veterinary vaccine design, and three different VLPs as promising platforms for DIVA vaccination strategies in animals.
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Affiliation(s)
- Fuxiao Liu
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, No. 5333 Xi'an Road, Changchun, Jilin 130062, China
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21
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Metz SW, Gardner J, Geertsema C, Le TT, Goh L, Vlak JM, Suhrbier A, Pijlman GP. Effective chikungunya virus-like particle vaccine produced in insect cells. PLoS Negl Trop Dis 2013; 7:e2124. [PMID: 23516657 PMCID: PMC3597470 DOI: 10.1371/journal.pntd.0002124] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2012] [Accepted: 02/06/2013] [Indexed: 01/21/2023] Open
Abstract
The emerging arthritogenic, mosquito-borne chikungunya virus (CHIKV) causes severe disease in humans and represents a serious public health threat in countries where Aedes spp mosquitoes are present. This study describes for the first time the successful production of CHIKV virus-like particles (VLPs) in insect cells using recombinant baculoviruses. This well-established expression system is rapidly scalable to volumes required for epidemic responses and proved well suited for processing of CHIKV glycoproteins and production of enveloped VLPs. Herein we show that a single immunization with 1 µg of non-adjuvanted CHIKV VLPs induced high titer neutralizing antibody responses and provided complete protection against viraemia and joint inflammation upon challenge with the Réunion Island CHIKV strain in an adult wild-type mouse model of CHIKV disease. CHIKV VLPs produced in insect cells using recombinant baculoviruses thus represents as a new, safe, non-replicating and effective vaccine candidate against CHIKV infections.
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MESH Headings
- Alphavirus Infections/immunology
- Alphavirus Infections/prevention & control
- Animals
- Antibodies, Neutralizing/blood
- Antibodies, Viral/blood
- Baculoviridae/genetics
- Cell Line
- Chikungunya Fever
- Chikungunya virus/genetics
- Chikungunya virus/immunology
- Disease Models, Animal
- Female
- Genetic Vectors
- Mice
- Mice, Inbred C57BL
- Spodoptera
- Vaccines, Synthetic/administration & dosage
- Vaccines, Synthetic/immunology
- Vaccines, Synthetic/isolation & purification
- Vaccines, Virus-Like Particle/administration & dosage
- Vaccines, Virus-Like Particle/immunology
- Vaccines, Virus-Like Particle/isolation & purification
- Viral Vaccines/administration & dosage
- Viral Vaccines/immunology
- Viral Vaccines/isolation & purification
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Affiliation(s)
- Stefan W. Metz
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands
| | - Joy Gardner
- Queensland Institute of Medical Research, Brisbane, Queensland, Australia
| | - Corinne Geertsema
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands
| | - Thuy T. Le
- Queensland Institute of Medical Research, Brisbane, Queensland, Australia
| | - Lucas Goh
- The University of Queensland, St. Lucia, Queensland, Australia
| | - Just M. Vlak
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands
| | - Andreas Suhrbier
- Queensland Institute of Medical Research, Brisbane, Queensland, Australia
| | - Gorben P. Pijlman
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands
- * E-mail:
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22
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Alto BW, Wasik BR, Morales NM, Turner PE. Stochastic temperatures impede RNA virus adaptation. Evolution 2013; 67:969-79. [PMID: 23550749 DOI: 10.1111/evo.12034] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Constant environments are often assumed to favor the evolution of specialization whereas exposure to changing environments may favor the evolution of generalists. Here we explored the phenotypic and molecular changes associated with evolving an RNA virus in constant versus fluctuating temperature environments. We used vesicular stomatitis virus (VSV) to determine whether selection at a constant temperature entails a performance trade-off at an unselected temperature, whether virus populations evolve to be generalists when selected in deterministically changing temperature environments, and whether selection under stochastically changing temperatures prevents evolved generalization, such as by constraining the ability for viruses to adaptively improve. We observed that all VSV lineages evolved at constant temperatures showed fitness gains in their selected temperature with little evidence for trade-offs in performance in the unselected environment. Evolution in deterministically and stochastically changing temperatures led to populations with the highest and lowest overall fitness gains, respectively. Sequence analysis revealed little evidence for convergent molecular evolution among lineages within the same treatment. Across all temperature treatments, the majority of genome substitutions occurred in the G (glycoprotein) gene, suggesting that this locus for the cell-binding protein plays a key role in dictating VSV performance under changing temperature.
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Affiliation(s)
- Barry W Alto
- Florida Medical Entomology Laboratory, University of Florida, Vero Beach, Florida 32962, USA.
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23
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Abstract
Over the last three decades, virus-like particles (VLPs) have evolved to become a widely accepted technology, especially in the field of vaccinology. In fact, some VLP-based vaccines are currently used as commercial medical products, and other VLP-based products are at different stages of clinical study. Several remarkable advantages have been achieved in the development of VLPs as gene therapy tools and new nanomaterials. The analysis of published data reveals that at least 110 VLPs have been constructed from viruses belonging to 35 different families. This review therefore discusses the main principles in the cloning of viral structural genes, the relevant host systems and the purification procedures that have been developed. In addition, the methods that are used to characterize the structural integrity, stability, and components, including the encapsidated nucleic acids, of newly synthesized VLPs are analyzed. Moreover, some of the modifications that are required to construct VLP-based carriers of viral origin with defined properties are discussed, and examples are provided.
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Affiliation(s)
- Andris Zeltins
- Latvian Biomedical Research and Study Centre, Ratsupites 1, Riga 1067, Latvia.
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24
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Pushko P, Pumpens P, Grens E. Development of Virus-Like Particle Technology from Small Highly Symmetric to Large Complex Virus-Like Particle Structures. Intervirology 2013; 56:141-65. [DOI: 10.1159/000346773] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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25
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Thim HL, Iliev DB, Christie KE, Villoing S, McLoughlin MF, Strandskog G, Jørgensen JB. Immunoprotective activity of a Salmonid Alphavirus Vaccine: comparison of the immune responses induced by inactivated whole virus antigen formulations based on CpG class B oligonucleotides and poly I:C alone or combined with an oil adjuvant. Vaccine 2012; 30:4828-34. [PMID: 22634299 DOI: 10.1016/j.vaccine.2012.05.010] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 04/13/2012] [Accepted: 05/07/2012] [Indexed: 12/25/2022]
Abstract
CpG oligonucleotides and polyinosinic:polycytidylic acid (poly I:C) are toll-like receptor (TLR) agonists that mimic the immunostimulatory properties of bacterial DNA and double-stranded viral RNA respectively, and which have exhibited potential to serve as vaccine adjuvants in previous experiments. Here, a combination of CpGs and poly I:C together with water- or oil-formulated Salmonid Alphavirus (SAV) antigen preparations has been used for a vaccine in Atlantic salmon and tested for protection in SAV challenge trial. The results demonstrate that vaccination with a high dose of the SAV antigen induced protection against challenge with SAV which correlated with production of neutralizing antibodies (NAbs). As the high antigen dose alone induced full protection, no beneficial effect from the addition of CpG and poly I:C could be observed. Nevertheless, these TLR ligands significantly enhanced the levels of NAbs in serum of vaccinated fish. Interestingly, gene expression analysis demonstrated that while addition of oil suppressed the CpG/poly I:C-induced expression of IFN-γ, the upregulation of IFNa1 was substantially enhanced. A low dose of the SAV antigen combined with oil did not induce any detectable levels of NAbs either with or without TLR ligands present, however the addition of CpG and poly I:C to the low SAV antigen dose formulation significantly enhanced the protection against SAV suggesting that CpG/poly I:C may have enhanced a cytotoxic response - a process which is dependent on the up-regulation of type I IFN. These results highlight the immunostimulatory properties of the tested TLR ligands and will serve as a ground for further, more detailed studies aimed to investigate their capacity to serve as adjuvants in vaccine formulations for Atlantic salmon.
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Affiliation(s)
- Hanna L Thim
- Norwegian College of Fisheries Science, University of Tromsø, N-9037 Tromsø, Norway
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