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Perveen N, Muhammad K, Muzaffar SB, Zaheer T, Munawar N, Gajic B, Sparagano OA, Kishore U, Willingham AL. Host-pathogen interaction in arthropod vectors: Lessons from viral infections. Front Immunol 2023; 14:1061899. [PMID: 36817439 PMCID: PMC9929866 DOI: 10.3389/fimmu.2023.1061899] [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: 10/05/2022] [Accepted: 01/17/2023] [Indexed: 02/04/2023] Open
Abstract
Haematophagous arthropods can harbor various pathogens including viruses, bacteria, protozoa, and nematodes. Insects possess an innate immune system comprising of both cellular and humoral components to fight against various infections. Haemocytes, the cellular components of haemolymph, are central to the insect immune system as their primary functions include phagocytosis, encapsulation, coagulation, detoxification, and storage and distribution of nutritive materials. Plasmatocytes and granulocytes are also involved in cellular defense responses. Blood-feeding arthropods, such as mosquitoes and ticks, can harbour a variety of viral pathogens that can cause infectious diseases in both human and animal hosts. Therefore, it is imperative to study the virus-vector-host relationships since arthropod vectors are important constituents of the ecosystem. Regardless of the complex immune response of these arthropod vectors, the viruses usually manage to survive and are transmitted to the eventual host. A multidisciplinary approach utilizing novel and strategic interventions is required to control ectoparasite infestations and block vector-borne transmission of viral pathogens to humans and animals. In this review, we discuss the arthropod immune response to viral infections with a primary focus on the innate immune responses of ticks and mosquitoes. We aim to summarize critically the vector immune system and their infection transmission strategies to mammalian hosts to foster debate that could help in developing new therapeutic strategies to protect human and animal hosts against arthropod-borne viral infections.
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Affiliation(s)
- Nighat Perveen
- Department of Biology, College of Science, United Arab Emirates University, Al-Ain, United Arab Emirates
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Khalid Muhammad
- Department of Biology, College of Science, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Sabir Bin Muzaffar
- Department of Biology, College of Science, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Tean Zaheer
- Department of Parasitology, University of Agriculture, Faisalabad, Pakistan
| | - Nayla Munawar
- Department of Chemistry, College of Science, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Bojan Gajic
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Olivier Andre Sparagano
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Uday Kishore
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al-Ain, United Arab Emirates
| | - Arve Lee Willingham
- Department of Veterinary Medicine, College of Agriculture and Veterinary Medicine, United Arab Emirates University, Al-Ain, United Arab Emirates
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2
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Diakou KI, Mitsis T, Pierouli K, Papakonstantinou E, Megalooikonomou V, Efthimiadou A, Vlachakis D. Study of the Langat virus RNA-dependent RNA polymerase through homology modeling. ACTA ACUST UNITED AC 2021; 26. [PMID: 34316455 PMCID: PMC8312719 DOI: 10.14806/ej.26.1.944] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Langat virus is a member of the Flaviviridae family and a close relative of a group of important tick-borne viruses that cause human encephalitis. RNA-dependent RNA polymerase is a significant component of the replication mechanism of the Flaviviridae viral family. In the present work, a three-dimensional model of the Langat virus RNA-dependent RNA polymerase was designed through homology modeling. The experimentally determined structure of the RNA-dependent RNA polymerase of Dengue virus type II, another member of the same viral family, was employed as template for the homology modeling process. The resulting model underwent a series of optimisations and its quality was verified using the Verify3D algorithm. Important functional characteristics of the family of viral RNA-dependent RNA polymerases were identified in the generated model, thus affirming the potential for its use in the possible design of anti-viral agents for Langat virus.
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Affiliation(s)
- Kalliopi Io Diakou
- Laboratory of Genetics, Department of Biotechnology, School of Applied Biology and Biotechnology, Agricultural University of Athens, Athens, Greece
| | - Thanasis Mitsis
- Laboratory of Genetics, Department of Biotechnology, School of Applied Biology and Biotechnology, Agricultural University of Athens, Athens, Greece
| | - Katerina Pierouli
- Laboratory of Genetics, Department of Biotechnology, School of Applied Biology and Biotechnology, Agricultural University of Athens, Athens, Greece
| | - Eleni Papakonstantinou
- Laboratory of Genetics, Department of Biotechnology, School of Applied Biology and Biotechnology, Agricultural University of Athens, Athens, Greece
| | - Vasileios Megalooikonomou
- Computer Engineering and Informatics Department, School of Engineering, University of Patras, Patras, Greece
| | - Aspasia Efthimiadou
- Department of Soil Science of Athens, Institute of Soil and Water Resources, Hellenic Agricultural Organization - Demeter, Attica, Greece
| | - Dimitrios Vlachakis
- Laboratory of Genetics, Department of Biotechnology, School of Applied Biology and Biotechnology, Agricultural University of Athens, Athens, Greece.,Lab of Molecular Endocrinology, Center of Clinical, Experimental Surgery and Translational Research, Biomedical Research Foundation of the Academy of Athens, Athens, Greece.,Department of Informatics, Faculty of Natural and Mathematical Sciences, King's College London, London, United Kingdom
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3
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Tran PTH, Asghar N, Johansson M, Melik W. Roles of the Endogenous Lunapark Protein during Flavivirus Replication. Viruses 2021; 13:v13071198. [PMID: 34206552 PMCID: PMC8310331 DOI: 10.3390/v13071198] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 06/08/2021] [Accepted: 06/17/2021] [Indexed: 12/19/2022] Open
Abstract
The endoplasmic reticulum (ER) of eukaryotic cells is a dynamic organelle, which undergoes continuous remodeling. At the three-way tubular junctions of the ER, the lunapark (LNP) protein acts as a membrane remodeling factor to stabilize these highly curved membrane junctions. In addition, during flavivirus infection, the ER membrane is invaginated to form vesicles (Ve) for virus replication. Thus, LNP may have roles in the generation or maintenance of the Ve during flavivirus infection. In this study, our aim was to characterize the functions of LNP during flavivirus infection and investigate the underlying mechanisms of these functions. To specifically study virus replication, we generated cell lines expressing replicons of West Nile virus (Kunjin strain) or Langat virus. By using these replicon platforms and electron microscopy, we showed that depletion of LNP resulted in reduced virus replication, which is due to its role in the generation of the Ve. By using biochemical assays and high-resolution microscopy, we found that LNP is recruited to the Ve and the protein interacts with the nonstructural protein (NS) 4B. Therefore, these data shed new light on the interactions between flavivirus and host factors during viral replication.
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4
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Immunity to TBEV Related Flaviviruses with Reduced Pathogenicity Protects Mice from Disease but Not from TBEV Entry into the CNS. Vaccines (Basel) 2021; 9:vaccines9030196. [PMID: 33652698 PMCID: PMC7996866 DOI: 10.3390/vaccines9030196] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 02/19/2021] [Accepted: 02/22/2021] [Indexed: 12/30/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV) is a leading cause of vector-borne viral encephalitis with expanding endemic regions across Europe. In this study we tested in mice the efficacy of preinfection with a closely related low-virulent flavivirus, Langat virus (LGTV strain TP21), or a naturally avirulent TBEV strain (TBEV-280) in providing protection against lethal infection with the highly virulent TBEV strain (referred to as TBEV-Hypr). We show that prior infection with TP21 or TBEV-280 is efficient in protecting mice from lethal TBEV-Hypr challenge. Histopathological analysis of brains from nonimmunized mice revealed neuronal TBEV infection and necrosis. Neuroinflammation, gliosis, and neuronal necrosis was however also observed in some of the TP21 and TBEV-280 preinfected mice although at reduced frequency as compared to the nonimmunized TBEV-Hypr infected mice. qPCR detected the presence of viral RNA in the CNS of both TP21 and TBEV-280 immunized mice after TBEV-Hypr challenge, but significantly reduced compared to mock-immunized mice. Our results indicate that although TBEV-Hypr infection is effectively controlled in the periphery upon immunization with low-virulent LGTV or naturally avirulent TBEV 280, it may still enter the CNS of these animals. These findings contribute to our understanding of causes for vaccine failure in individuals vaccinated with TBE vaccines.
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5
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Lindqvist R, Rosendal E, Weber E, Asghar N, Schreier S, Lenman A, Johansson M, Dobler G, Bestehorn M, Kröger A, Överby AK. The envelope protein of tick-borne encephalitis virus influences neuron entry, pathogenicity, and vaccine protection. J Neuroinflammation 2020; 17:284. [PMID: 32988388 PMCID: PMC7523050 DOI: 10.1186/s12974-020-01943-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 08/26/2020] [Indexed: 12/29/2022] Open
Abstract
Background Tick-borne encephalitis virus (TBEV) is considered to be the medically most important arthropod-borne virus in Europe. The symptoms of an infection range from subclinical to mild flu-like disease to lethal encephalitis. The exact determinants of disease severity are not known; however, the virulence of the strain as well as the immune status of the host are thought to be important factors for the outcome of the infection. Here we investigated virulence determinants in TBEV infection. Method Mice were infected with different TBEV strains, and high virulent and low virulent TBEV strains were chosen. Sequence alignment identified differences that were cloned to generate chimera virus. The infection rate of the parental and chimeric virus were evaluated in primary mouse neurons, astrocytes, mouse embryonic fibroblasts, and in vivo. Neutralizing capacity of serum from individuals vaccinated with the FSME-IMMUN® and Encepur® or combined were evaluated. Results We identified a highly pathogenic and neurovirulent TBEV strain, 93/783. Using sequence analysis, we identified the envelope (E) protein of 93/783 as a potential virulence determinant and cloned it into the less pathogenic TBEV strain Torö. We found that the chimeric virus specifically infected primary neurons more efficiently compared to wild-type (WT) Torö and this correlated with enhanced pathogenicity and higher levels of viral RNA in vivo. The E protein is also the major target of neutralizing antibodies; thus, genetic variation in the E protein could influence the efficiency of the two available vaccines, FSME-IMMUN® and Encepur®. As TBEV vaccine breakthroughs have occurred in Europe, we chose to compare neutralizing capacity from individuals vaccinated with the two different vaccines or a combination of them. Our data suggest that the different vaccines do not perform equally well against the two Swedish strains. Conclusions Our findings show that two amino acid substitutions of the E protein found in 93/783, A83T, and A463S enhanced Torö infection of neurons as well as pathogenesis and viral replication in vivo; furthermore, we found that genetic divergence from the vaccine strain resulted in lower neutralizing antibody titers in vaccinated individuals.
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Affiliation(s)
- Richard Lindqvist
- Department of Clinical Microbiology, Section of Virology, Umeå University, Umeå, Sweden.,The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå, Sweden
| | - Ebba Rosendal
- Department of Clinical Microbiology, Section of Virology, Umeå University, Umeå, Sweden.,The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå, Sweden
| | - Elvira Weber
- Department of Clinical Microbiology, Section of Virology, Umeå University, Umeå, Sweden.,The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå, Sweden.,Current affiliation: Life & Medical Sciences Institute (LIMES), University of Bonn, Bonn, Germany
| | - Naveed Asghar
- School of Medical Sciences, Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | - Sarah Schreier
- Institute of Medical Microbiology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.,Innate Immunity and Infection, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Annasara Lenman
- Department of Clinical Microbiology, Section of Virology, Umeå University, Umeå, Sweden.,Institute for Experimental Virology, TWINCORE, Centre for Experimental and Clinical Infection Research, a joint venture between the Medical School Hannover and the Helmholtz Centre for Infection Research, Hannover, Germany
| | - Magnus Johansson
- School of Medical Sciences, Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and Health, Örebro University, Örebro, Sweden
| | | | - Malena Bestehorn
- Bundeswehr Institute of Microbiology, Munich, Germany.,Parasitology Unit, University of Hohenheim, D-, Stuttgart, Germany
| | - Andrea Kröger
- Institute of Medical Microbiology, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany. .,Innate Immunity and Infection, Helmholtz Centre for Infection Research, Braunschweig, Germany.
| | - Anna K Överby
- Department of Clinical Microbiology, Section of Virology, Umeå University, Umeå, Sweden. .,The Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå, Sweden.
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6
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In Vivo Characterization of Tick-Borne Encephalitis Virus in Bank Voles ( Myodes glareolus). Viruses 2019; 11:v11111069. [PMID: 31731773 PMCID: PMC6893798 DOI: 10.3390/v11111069] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 11/07/2019] [Accepted: 11/13/2019] [Indexed: 12/30/2022] Open
Abstract
Tick-borne encephalitis is the most important tick-transmitted zoonotic virus infection in Eurasia, causing severe neurological symptoms in humans. The causative agent, the tick-borne encephalitis virus (TBEV), circulates between ticks and a variety of mammalian hosts. To study the interaction between TBEV and one of its suspected reservoir hosts, bank voles of the Western evolutionary lineage were inoculated subcutaneously with either one of eight TBEV strains or the related attenuated Langat virus, and were euthanized after 28 days. In addition, a subset of four strains was characterized in bank voles of the Carpathian linage. Six bank voles were inoculated per strain, and were housed together in groups of three with one uninfected in-contact animal each. Generally, most bank voles did not show any clinical signs over the course of infection. However, one infected bank vole died and three had to be euthanized prematurely, all of which had been inoculated with the identical TBEV strain (Battaune 17-H9, isolated in 2017 in Germany from a bank vole). All inoculated animals seroconverted, while none of the in-contact animals did. Viral RNA was detected via real-time RT-PCR in the whole blood samples of 31 out of 74 inoculated and surviving bank voles. The corresponding serum sample remained PCR-negative in nearly all cases (29/31). In addition, brain and/or spine samples tested positive in 11 cases, mostly correlating with a positive whole blood sample. Our findings suggest a good adaption of TBEV to bank voles, combining in most cases a low virulence phenotype with detectable virus replication and hinting at a reservoir host function of bank voles for TBEV.
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7
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Velay A, Paz M, Cesbron M, Gantner P, Solis M, Soulier E, Argemi X, Martinot M, Hansmann Y, Fafi-Kremer S. Tick-borne encephalitis virus: molecular determinants of neuropathogenesis of an emerging pathogen. Crit Rev Microbiol 2019; 45:472-493. [PMID: 31267816 DOI: 10.1080/1040841x.2019.1629872] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Tick-borne encephalitis virus (TBEV) is a zoonotic agent causing severe encephalitis. The transmission cycle involves the virus, the Ixodes tick vector, and a vertebrate reservoir, such as small mammals (rodents, or shrews). Humans are accidentally involved in this transmission cycle. Tick-borne encephalitis (TBE) has been a growing public health problem in Europe and Asia over the past 30 years. The mechanisms involved in the development of TBE are very complex and likely multifactorial, involving both host and viral factors. The purpose of this review is to provide an overview of the current literature on TBE neuropathogenesis in the human host and to demonstrate the emergence of common themes in the molecular pathogenesis of TBE in humans. We discuss and review data on experimental study models and on both viral (molecular genetics of TBEV) and host (immune response, and genetic background) factors involved in TBE neuropathogenesis in the context of human infection.
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Affiliation(s)
- Aurélie Velay
- Virology Laboratory, University Hospital of Strasbourg , Strasbourg , France.,INSERM, IRM UMR_S 1109 , Strasbourg , France
| | - Magali Paz
- Virology Laboratory, University Hospital of Strasbourg , Strasbourg , France
| | - Marlène Cesbron
- Virology Laboratory, University Hospital of Strasbourg , Strasbourg , France
| | - Pierre Gantner
- Virology Laboratory, University Hospital of Strasbourg , Strasbourg , France.,INSERM, IRM UMR_S 1109 , Strasbourg , France
| | - Morgane Solis
- Virology Laboratory, University Hospital of Strasbourg , Strasbourg , France.,INSERM, IRM UMR_S 1109 , Strasbourg , France
| | | | - Xavier Argemi
- Service des maladies infectieuses et tropicales, Hôpitaux Universitaires de Strasbourg , Strasbourg , France
| | - Martin Martinot
- Service de Médecine Interne et de Rhumatologie, Hôpitaux Civils de Colmar , Colmar , France
| | - Yves Hansmann
- Service des maladies infectieuses et tropicales, Hôpitaux Universitaires de Strasbourg , Strasbourg , France
| | - Samira Fafi-Kremer
- Virology Laboratory, University Hospital of Strasbourg , Strasbourg , France.,INSERM, IRM UMR_S 1109 , Strasbourg , France
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8
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Youseff BH, Brewer TG, McNally KL, Izuogu AO, Lubick KJ, Presloid JB, Alqahtani S, Chattopadhyay S, Best SM, Hu X, Taylor RT. TRAF6 Plays a Proviral Role in Tick-Borne Flavivirus Infection through Interaction with the NS3 Protease. iScience 2019; 15:489-501. [PMID: 31129244 PMCID: PMC6536497 DOI: 10.1016/j.isci.2019.05.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 01/18/2019] [Accepted: 05/08/2019] [Indexed: 02/08/2023] Open
Abstract
Tick-borne flaviviruses (TBFVs) can cause life-threatening encephalitis and hemorrhagic fever. To identify virus-host interactions that may be exploited as therapeutic targets, we analyzed the TBFV polyprotein in silico for antiviral protein-binding motifs. We obtained two putative tumor necrosis factor receptor-associated factor 6 (TRAF6)-binding motifs (TBMs) within the protease domain of the viral nonstructural 3 (NS3) protein. Here, we show that TBFV NS3 interacted with TRAF6 during infection and that TRAF6 supports TBFV replication. The proviral role of TRAF6 was not seen with mosquito-borne flaviviruses, consistent with the lack of conserved TBMs. Mutation of the second TBM within NS3 disrupted TRAF6 binding, coincident with reduced abundance of mature, autocatalytically derived form of the NS3 protease and significant virus attenuation in vitro. Our studies reveal insights into how flaviviruses exploit innate immunity for the purpose of viral replication and identify a potential target for therapeutic design. Langat virus (LGTV) NS3 protease interacts with TRAF6 during infection Tick-borne, unlike mosquito-borne, flaviviruses use TRAF6 for optimal replication E117A mutation of LGTV NS3 reduces TRAF6 binding and mature protease abundance LGTV with a mutated TRAF6-binding motif is attenuated in vitro
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Affiliation(s)
- Brian H Youseff
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
| | - Thomas G Brewer
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
| | - Kristin L McNally
- Innate Immunity and Pathogenesis Unit, Laboratory of Virology, Rocky Mountain Laboratories, DIR, NIAID, NIH, Hamilton, MT 59840, USA
| | - Adaeze O Izuogu
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
| | - Kirk J Lubick
- Innate Immunity and Pathogenesis Unit, Laboratory of Virology, Rocky Mountain Laboratories, DIR, NIAID, NIH, Hamilton, MT 59840, USA
| | - John B Presloid
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
| | - Saad Alqahtani
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, OH 43606, USA
| | - Saurabh Chattopadhyay
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
| | - Sonja M Best
- Innate Immunity and Pathogenesis Unit, Laboratory of Virology, Rocky Mountain Laboratories, DIR, NIAID, NIH, Hamilton, MT 59840, USA
| | - Xiche Hu
- Department of Chemistry and Biochemistry, University of Toledo, Toledo, OH 43606, USA
| | - R Travis Taylor
- Department of Medical Microbiology and Immunology, University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA.
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9
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The distribution of important sero-complexes of flaviviruses in Malaysia. Trop Anim Health Prod 2019; 51:495-506. [PMID: 30604332 DOI: 10.1007/s11250-018-01786-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 12/13/2018] [Indexed: 12/13/2022]
Abstract
Flaviviruses (FVs) are arthropod-borne viruses of medical and veterinary importance. Numerous species of FVs have been isolated from various host; mainly humans, animals, ticks, and mosquitoes. Certain FVs are extremely host-specific; at the same time, some FVs can infect an extensive range of species. Based on published literatures, 11 species of FVs have been detected from diverse host species in Malaysia. In humans, dengue virus and Japanese encephalitis virus have been reported since 1901 and 1942. In animals, the Batu Cave virus, Sitiawan virus, Carey Island, Tembusu virus, Duck Tembusu virus, and Japanese encephalitis viruses were isolated from various species. In mosquitoes, Japanese encephalitis virus and Kunjin virus were isolated from Culex spp., while Zika virus and Jugra virus were isolated from Aedes spp. In ticks, the Langat virus was isolated from Ixodes spp. One of the major challenges in the diagnosis of FVs is the presence of sero-complexes as a result of cross-reactivity with one or more FV species. Subsequently, the distribution of specific FVs among humans and animals in a specific population is problematic to assess and often require comprehensive and thorough analyses. Molecular assays such as quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and digital droplet RT-PCR (ddRT-PCR) have been used for the differentiation of flavivirus infections to increase the accuracy of epidemiological data for disease surveillance, monitoring, and control. In situations where sero-complexes are common in FVs, even sensitive assays such as qRT-pCR can produce false positive results. In this write up, an overview of the various FV sero-complexes reported in Malaysia to date and the challenges faced in diagnosis of FV infections are presented.
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10
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Giel-Moloney M, Goncalvez AP, Catalan J, Lecouturier V, Girerd-Chambaz Y, Diaz F, Maldonado-Arocho F, Gomila RC, Bernard MC, Oomen R, Delagrave S, Burdin N, Kleanthous H, Jackson N, Heinrichs J, Pugachev KV. Chimeric yellow fever 17D-Zika virus (ChimeriVax-Zika) as a live-attenuated Zika virus vaccine. Sci Rep 2018; 8:13206. [PMID: 30181550 PMCID: PMC6123396 DOI: 10.1038/s41598-018-31375-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 08/17/2018] [Indexed: 11/15/2022] Open
Abstract
Zika virus (ZIKV) is an emerging mosquito-borne pathogen representing a global health concern. It has been linked to fetal microcephaly and other birth defects and neurological disorders in adults. Sanofi Pasteur has engaged in the development of an inactivated ZIKV vaccine, as well as a live chimeric vaccine candidate ChimeriVax-Zika (CYZ) that could become a preferred vaccine depending on future ZIKV epidemiology. This report focuses on the CYZ candidate that was constructed by replacing the pre-membrane and envelope (prM-E) genes in the genome of live attenuated yellow fever 17D vaccine virus (YF 17D) with those from ZIKV yielding a viable CYZ chimeric virus. The replication rate of CYZ in the Vero cell substrate was increased by using a hybrid YF 17D-ZIKV signal sequence for the prM protein. CYZ was highly attenuated both in mice and in human in vitro models (human neuroblastoma and neuronal progenitor cells), without the need for additional attenuating modifications. It exhibited significantly reduced viral loads in organs compared to a wild-type ZIKV and a complete lack of neuroinvasion following inoculation of immunodeficient A129 mice. A single dose of CYZ elicited high titers of ZIKV-specific neutralizing antibodies in both immunocompetent and A129 mice and protected animals from ZIKV challenge. The data indicate that CYZ is a promising vaccine candidate against ZIKV.
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Affiliation(s)
| | | | - John Catalan
- Sanofi Pasteur Research & Development, Cambridge, MA, USA
| | | | | | - Fernando Diaz
- Sanofi Pasteur Research & Development, Cambridge, MA, USA.,VL46 Inc., Cambridge, MA, USA
| | | | - Raul C Gomila
- Sanofi Pasteur Research & Development, Cambridge, MA, USA
| | | | - Ray Oomen
- Sanofi Pasteur Research & Development, Cambridge, MA, USA
| | | | - Nicolas Burdin
- Sanofi Pasteur Research & Development, Marcy-l'Étoile, France
| | | | - Nicolas Jackson
- Sanofi Pasteur Research & Development, Marcy-l'Étoile, France
| | - Jon Heinrichs
- Sanofi Pasteur Research & Development, Swiftwater, PA, USA
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11
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Kellman EM, Offerdahl DK, Melik W, Bloom ME. Viral Determinants of Virulence in Tick-Borne Flaviviruses. Viruses 2018; 10:v10060329. [PMID: 29914165 PMCID: PMC6024809 DOI: 10.3390/v10060329] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 06/12/2018] [Accepted: 06/15/2018] [Indexed: 12/27/2022] Open
Abstract
Tick-borne flaviviruses have a global distribution and cause significant human disease, including encephalitis and hemorrhagic fever, and often result in neurologic sequelae. There are two distinct properties that determine the neuropathogenesis of a virus. The ability to invade the central nervous system (CNS) is referred to as the neuroinvasiveness of the agent, while the ability to infect and damage cells within the CNS is referred to as its neurovirulence. Examination of laboratory variants, cDNA clones, natural isolates with varying pathogenicity, and virally encoded immune evasion strategies have contributed extensively to our understanding of these properties. Here we will review the major viral determinants of virulence that contribute to pathogenesis and influence both neuroinvasiveness and neurovirulence properties of tick-borne flaviviruses, focusing particularly on the envelope protein (E), nonstructural protein 5 (NS5), and the 3′ untranslated region (UTR).
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Affiliation(s)
- Eliza M Kellman
- Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT 59840, USA.
| | - Danielle K Offerdahl
- Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT 59840, USA.
| | - Wessam Melik
- School of Medical Sciences, Orebro University, SE-703 62 Örebro, Sweden.
| | - Marshall E Bloom
- Laboratory of Virology, Rocky Mountain Laboratories, NIAID, NIH, Hamilton, MT 59840, USA.
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12
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Eyer L, Nencka R, de Clercq E, Seley-Radtke K, Růžek D. Nucleoside analogs as a rich source of antiviral agents active against arthropod-borne flaviviruses. Antivir Chem Chemother 2018; 26:2040206618761299. [PMID: 29534608 PMCID: PMC5890575 DOI: 10.1177/2040206618761299] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 01/30/2018] [Indexed: 12/27/2022] Open
Abstract
Nucleoside analogs represent the largest class of small molecule-based antivirals, which currently form the backbone of chemotherapy of chronic infections caused by HIV, hepatitis B or C viruses, and herpes viruses. High antiviral potency and favorable pharmacokinetics parameters make some nucleoside analogs suitable also for the treatment of acute infections caused by other medically important RNA and DNA viruses. This review summarizes available information on antiviral research of nucleoside analogs against arthropod-borne members of the genus Flavivirus within the family Flaviviridae, being primarily focused on description of nucleoside inhibitors of flaviviral RNA-dependent RNA polymerase, methyltransferase, and helicase/NTPase. Inhibitors of intracellular nucleoside synthesis and newly discovered nucleoside derivatives with high antiflavivirus potency, whose modes of action are currently not completely understood, have drawn attention. Moreover, this review highlights important challenges and complications in nucleoside analog development and suggests possible strategies to overcome these limitations.
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Affiliation(s)
- Luděk Eyer
- Department of Virology, Veterinary Research Institute, Brno, Czech Republic
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
| | - Radim Nencka
- Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Prague, Czech Republic
| | - Erik de Clercq
- Rega Institute for Medical Research, KU Leuven, Leuven, Belgium
| | | | - Daniel Růžek
- Department of Virology, Veterinary Research Institute, Brno, Czech Republic
- Institute of Parasitology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Czech Republic
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13
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Smith DR, Sprague TR, Hollidge BS, Valdez SM, Padilla SL, Bellanca SA, Golden JW, Coyne SR, Kulesh DA, Miller LJ, Haddow AD, Koehler JW, Gromowski GD, Jarman RG, Alera MTP, Yoon IK, Buathong R, Lowen RG, Kane CD, Minogue TD, Bavari S, Tesh RB, Weaver SC, Linthicum KJ, Pitt ML, Nasar F. African and Asian Zika Virus Isolates Display Phenotypic Differences Both In Vitro and In Vivo. Am J Trop Med Hyg 2017; 98:432-444. [PMID: 29280428 DOI: 10.4269/ajtmh.17-0685] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Zika virus (ZIKV) is a mosquito-borne member of the genus Flavivirus that has emerged since 2007 to cause outbreaks in Africa, Asia, Oceania, and most recently, in the Americas. Here, we used an isolate history as well as genetic and phylogenetic analyses to characterize three low-passage isolates representing African (ArD 41525) and Asian (CPC-0740, SV0127-14) lineages to investigate the potential phenotypic differences in vitro and in vivo. The African isolate displayed a large plaque phenotype (∼3-4 mm) on Vero and HEK-293 cells, whereas the Asian isolates either exhibited a small plaque phenotype (∼1-2 mm) or did not produce any plaques. In multistep replication kinetics in nine different vertebrate and insect cell lines, the African isolate consistently displayed faster replication kinetics and yielded ∼10- to 10,000-fold higher peak virus titers (infectious or RNA copies) compared with the Asian isolates. Oral exposure of Aedes aegypti mosquitoes with the African isolate yielded higher infection and dissemination rates compared with the Asian isolates. Infection of Ifnar1-/- mice with the African isolate produced a uniformly fatal disease, whereas infection with the Asian isolates produced either a delay in time-to-death or a significantly lower mortality rate. Last, the African isolate was > 10,000-fold more virulent than the Asian isolates in an interferon type I antibody blockade mouse model. These data demonstrate substantial phenotypic differences between low-passage African and Asian isolates both in vitro and in vivo and warrant further investigation. They also highlight the need for basic characterization of ZIKV isolates, as the utilization of the uncharacterized isolates could have consequences for animal model and therapeutic/vaccine development.
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Affiliation(s)
- Darci R Smith
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Thomas R Sprague
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Bradley S Hollidge
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Stephanie M Valdez
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Susana L Padilla
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Stephanie A Bellanca
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Joseph W Golden
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Susan R Coyne
- Diagnostics Systems Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - David A Kulesh
- Diagnostics Systems Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Lynn Jean Miller
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Andrew D Haddow
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Jeff W Koehler
- Diagnostics Systems Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | | | | | - Maria Theresa P Alera
- Department of Virology, Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand
| | - In-Kyu Yoon
- International Vaccine Institute, Seoul, Republic of Korea
| | - Rome Buathong
- Department of Disease Control, Bureau of Epidemiology, Ministry of Public Health, Nonthaburi, Thailand
| | - Robert G Lowen
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Christopher D Kane
- Molecular and Translational Sciences Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Timothy D Minogue
- Diagnostics Systems Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Sina Bavari
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Robert B Tesh
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas.,Department of Pathology, University of Texas Medical Branch, Galveston, Texas.,Institute for Human Infections and Immunity, Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
| | - Scott C Weaver
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas.,Department of Pathology, University of Texas Medical Branch, Galveston, Texas.,Institute for Human Infections and Immunity, Center for Tropical Diseases, University of Texas Medical Branch, Galveston, Texas
| | - Kenneth J Linthicum
- Center for Medical, Agricultural and Veterinary Entomology, Agricultural Research Service, United States Department of Agriculture, Gainesville, Florida
| | - Margaret L Pitt
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland
| | - Farooq Nasar
- Virology Division, United States Army Medical Research Institute of Infectious Diseases, Frederick, Maryland.,Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas
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14
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Michlmayr D, Bardina SV, Rodriguez CA, Pletnev AG, Lim JK. Dual Function of Ccr5 during Langat Virus Encephalitis: Reduction in Neutrophil-Mediated Central Nervous System Inflammation and Increase in T Cell-Mediated Viral Clearance. THE JOURNAL OF IMMUNOLOGY 2016; 196:4622-31. [PMID: 27183602 DOI: 10.4049/jimmunol.1502452] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 03/29/2016] [Indexed: 12/30/2022]
Abstract
Tick-borne encephalitis virus (TBEV) is a vector-transmitted flavivirus that causes potentially fatal neurologic infection. There are thousands of cases reported annually, and despite the availability of an effective vaccine, the incidence of TBEV is increasing worldwide. Importantly, up to 30% of affected individuals develop long-term neurologic sequelae. We investigated the role of chemokine receptor Ccr5 in a mouse model of TBEV infection using the naturally attenuated tick-borne flavivirus Langat virus (LGTV). Ccr5-deficient mice presented with an increase in viral replication within the CNS and decreased survival during LGTV encephalitis compared with wild-type controls. This enhanced susceptibility was due to the temporal lag in lymphocyte migration into the CNS. Adoptive transfer of wild-type T cells, but not Ccr5-deficient T cells, significantly improved survival outcome in LGTV-infected Ccr5-deficient mice. Concomitantly, a significant increase in neutrophil migration into the CNS in LGTV-infected Ccr5(-/-) mice was documented at the late stage of infection. Ab-mediated depletion of neutrophils in Ccr5(-/-) mice resulted in a significant improvement in mortality, a decrease in viral load, and a decrease in overall tissue damage in the CNS compared with isotype control-treated mice. Ccr5 is crucial in directing T cells toward the LGTV-infected brain, as well as in suppressing neutrophil-mediated inflammation within the CNS.
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Affiliation(s)
- Daniela Michlmayr
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029; and
| | - Susana V Bardina
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029; and
| | - Carlos A Rodriguez
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029; and
| | - Alexander G Pletnev
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Jean K Lim
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY 10029; and
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15
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MicroRNA-based control of tick-borne flavivirus neuropathogenesis: Challenges and perspectives. Antiviral Res 2016; 127:57-67. [PMID: 26794396 DOI: 10.1016/j.antiviral.2016.01.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 12/10/2015] [Accepted: 01/13/2016] [Indexed: 01/01/2023]
Abstract
In recent years, microRNA-targeting has become an effective strategy for selective control of tissue-tropism and pathogenicity of both DNA and RNA viruses. Previously, we reported the successful application of this strategy to control the neurovirulent phenotype of a model chimeric tick-borne encephalitis/dengue type 4 virus (TBEV/DEN4), containing the structural protein genes of a highly virulent TBEV in the genetic backbone of non-neuroinvasive DEN4 virus. In the present study, we investigated the suitability of this approach for the attenuation of the more neurovirulent chimeric virus (TBEV/LGTV), which is based on the genetic backbone of the naturally attenuated member of the TBEV serocomplex, a Langat virus (LGTV). Unlike the TBEV/DEN4, the TBEV/LGTV virus retained the ability of its parental viruses to spread from the peripheral site of inoculation to the CNS. We evaluated ten potential sites in the 3'NCR of the TBEV/LGTV genome for placement of microRNA (miRNA) targets and found that the TBEV/LGTV genome is more restrictive for such genetic manipulations compared to TBEV/DEN4. In addition, unlike TBEV/DEN4 virus, the introduction of multiple miRNA targets into either the 3'NCR or ORF of the TBEV/LGTV genome had only a modest effect on virus attenuation in the developing CNS of highly permissive newborn mice. However, simultaneous miRNA-targeting in the ORF and 3'NCR had synergistic effect on control and silencing of virus replication in the brain and completely abolished the virus neurotropism. Furthermore, neuroinvasiveness of miRNA-targeted TBEV/LGTV viruses in very sensitive immunodeficient SCID mice was significantly limited. Immunocompetent animals immunized with such viruses were completely protected against challenge with the neurovirulent LGTV parent. These findings support the rationale of the miRNA-targeting approach to develop live attenuated virus vaccines against various neurotropic viruses.
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16
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Nishiyama S, Ikegami T. Temperature-sensitive mutations for live-attenuated Rift Valley fever vaccines: implications from other RNA viruses. Front Microbiol 2015; 6:787. [PMID: 26322023 PMCID: PMC4531298 DOI: 10.3389/fmicb.2015.00787] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 07/20/2015] [Indexed: 11/13/2022] Open
Abstract
Rift Valley fever (RVF) is a mosquito-borne zoonotic disease endemic to the African continent. RVF is characterized by high rate of abortions in ruminants and hemorrhagic fever, encephalitis, or blindness in humans. RVF is caused by the Rift Valley fever virus (RVFV: genus Phlebovirus, family Bunyaviridae). Vaccination is the only known effective strategy to prevent the disease, but there are no licensed RVF vaccines available for humans. A live-attenuated vaccine candidate derived from the wild-type pathogenic Egyptian ZH548 strain, MP-12, has been conditionally licensed for veterinary use in the U.S. MP-12 displays a temperature-sensitive (ts) phenotype and does not replicate at 41°C. The ts mutation limits viral replication at a specific body temperature and may lead to an attenuation of the virus. Here we will review well-characterized ts mutations for RNA viruses, and further discuss the potential in designing novel live-attenuated vaccines for RVF.
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Affiliation(s)
- Shoko Nishiyama
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, TX USA
| | - Tetsuro Ikegami
- Department of Pathology, The University of Texas Medical Branch at Galveston, Galveston, TX USA ; Sealy Center for Vaccine Development, The University of Texas Medical Branch at Galveston, Galveston, TX USA ; Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch at Galveston, Galveston, TX USA
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17
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Mohd Shukri M, Ling Kho K, Ghane Kisomi M, Lani R, Marlina S, Muhd Radzi SF, Tee Tay S, Ping Wong L, Awang Mahmud AB, Hassan Nizam QN, Abu Bakar S, Zandi K. Seroprevalence report on tick-borne encephalitis virus and Crimean-Congo hemorrhagic fever virus among Malaysian's farm workers. BMC Public Health 2015. [PMID: 26205588 PMCID: PMC4513429 DOI: 10.1186/s12889-015-1901-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Background Tick-borne encephalitis virus (TBEV) and Crimean-Congo haemorrhagic fever virus (CCHFV) are important tick-borne viruses. Despite their wide geographical distribution and ease of acquisition, the prevalence of both viruses in Malaysia is still unknown. This study was conducted to determine the seroprevalence for TBEV and CCHFV among Malaysian farm workers as a high-risk group within the population. Methods We gave questionnaires to 209 farm workers and invited them to participate in the study. Eighty-five agreed to do so. We then collected and tested sera for the presence of anti-TBEV IgG (immunoglobulin G) and anti-CCHFV IgG using a commercial enzyme-linked immunosorbent assay (ELISA) kit. We also tested seroreactive samples against three other related flaviviruses: dengue virus (DENV), West Nile virus (WNV) and Japanese encephalitis virus (JEV) using the ELISA method. Results The preliminary results showed the presence of anti-TBEV IgG in 31 (36.5 %) of 85 sera. However, when testing all the anti-TBEV IgG positive sera against the other three antigenically related flaviviruses to exclude possible cross reactivity, only five (4.2 %) sera did not show any cross reactivity. Interestingly, most (70.97 %) seropositives subjects mentioned tick-bite experience. However, there was no seroreactive sample for CCHFV. Conclusions These viruses migrate to neighbouring countries so they should be considered threats for the future, despite the low seroprevalence for TBEV and no serological evidence for CCHFV in this study. Therefore, further investigation involving a large number of human, animal and tick samples that might reveal the viruses’ true prevalence is highly recommended.
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Affiliation(s)
- Munirah Mohd Shukri
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Kai Ling Kho
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Masoumeh Ghane Kisomi
- Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Rafidah Lani
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Suria Marlina
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Siti Fatimah Muhd Radzi
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Sun Tee Tay
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Li Ping Wong
- Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Awang Bulgiba Awang Mahmud
- Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | | | - Sazaly Abu Bakar
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
| | - Keivan Zandi
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
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18
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Muto M, Bazartseren B, Tsevel B, Dashzevge E, Yoshii K, Kariwa H. Isolation and characterization of tick-borne encephalitis virus from Ixodes persulcatus in Mongolia in 2012. Ticks Tick Borne Dis 2015; 6:623-9. [PMID: 26025267 DOI: 10.1016/j.ttbdis.2015.05.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 03/16/2015] [Accepted: 05/09/2015] [Indexed: 10/23/2022]
Abstract
Tick-borne encephalitis virus (TBEV) is a zoonotic virus belonging to the genus Flavivirus, in the family Flaviviridae. The virus, which is endemic in Europe and northern parts of Asia, causes severe encephalitis. Tick-borne encephalitis (TBE) has been reported in Mongolia since the 1980s, but details about the biological characteristics of the endemic virus are lacking. In this study, 680 ticks (Ixodes persulcatus) were collected in Selenge aimag, northern Mongolia, in 2012. Nine Mongolian TBEV strains were isolated from tick homogenates. A sequence analysis of the envelope protein gene revealed that all isolates belonged to the Siberian subtype of TBEV. Two strains showed similar growth properties in cultured cells, but their virulence in mice differed. Whole genome sequencing revealed only thirteen amino acid differences between these Mongolian TBEV strains. Our results suggest that these naturally occurring amino acid mutations affected the pathogenicity of Mongolian TBEV. Our results may be an important platform for monitoring TBEV to evaluate the epidemiological risk in TBE endemic areas of Mongolia.
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Affiliation(s)
- Memi Muto
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - Boldbaatar Bazartseren
- Laboratory of Virology, Institute of Veterinary Medicine, Mongolian State University of Agriculture, Zaisan, Ulaanbaatar 17024, Mongolia
| | - Bazartseren Tsevel
- Laboratory of Virology, Institute of Veterinary Medicine, Mongolian State University of Agriculture, Zaisan, Ulaanbaatar 17024, Mongolia
| | - Erdenechimeg Dashzevge
- Laboratory of Virology, Institute of Veterinary Medicine, Mongolian State University of Agriculture, Zaisan, Ulaanbaatar 17024, Mongolia
| | - Kentaro Yoshii
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan.
| | - Hiroaki Kariwa
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
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19
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A tick-borne encephalitis model in infant rats infected with langat virus. J Neuropathol Exp Neurol 2015; 73:1107-15. [PMID: 25383637 DOI: 10.1097/nen.0000000000000131] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV) is the causative agent of human TBE, a severe infection that can cause long-lasting neurologic sequelae. Langat virus (LGTV), which is closely related to TBEV, has a low virulence for human hosts and has been used as a live vaccine against TBEV. Tick-borne encephalitis by natural infection of LGTV in humans has not been described, but one of 18,500 LGTV vaccinees developed encephalitis. The pathogenetic mechanisms of TBEV are poorly understood and, currently, no effective therapy is available. We developed an infant rat model of TBE using LGTV as infective agent. Infant Wistar rats were inoculated intracisternally with 10 focus-forming units of LGTV and assessed for clinical disease and neuropathologic findings at Days 2, 4, 7, and 9 after infection. Infection with LGTV led to gait disturbance, hypokinesia, and reduced weight gain or weight loss. Cerebrospinal fluid concentrations of RANTES, interferon-γ, interferon-β, interleukin-6, and monocyte chemotactic protein-1 were increased in infected animals. The brains of animals with LGTV encephalitis exhibited characteristic perivascular inflammatory cuffs and glial nodules; immunohistochemistry documented the presence of LGTV in the thalamus, hippocampus, midbrain, frontal pole, and cerebellum. Thus, LGTV meningoencephalitis in infant rats mimics important clinical and histopathologic features of human TBE. This new model provides a tool to investigate disease mechanisms and to evaluate new therapeutic strategies against encephalitogenic flaviviruses.
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20
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Kim YI, Murphy R, Majumdar S, Harrison LG, Aitken J, DeVincenzo JP. Relating plaque morphology to respiratory syncytial virus subgroup, viral load, and disease severity in children. Pediatr Res 2015; 78:380-8. [PMID: 26107392 PMCID: PMC4589428 DOI: 10.1038/pr.2015.122] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 03/26/2015] [Indexed: 12/23/2022]
Abstract
BACKGROUND Viral culture plaque morphology in human cell lines are markers for growth capability and cytopathic effect, and have been used to assess viral fitness and select preattenuation candidates for live viral vaccines. We classified respiratory syncytial virus (RSV) plaque morphology and analyzed the relationship between plaque morphology as compared to subgroup, viral load and clinical severity of infection in infants and children. METHODS We obtained respiratory secretions from 149 RSV-infected children. Plaque morphology and viral load was assessed within the first culture passage in HEp-2 cells. Viral load was measured by polymerase chain reaction (PCR), as was RSV subgroup. Disease severity was determined by hospitalization, length of stay, intensive care requirement, and respiratory failure. RESULTS Plaque morphology varied between individual subjects; however, similar results were observed among viruses collected from upper and lower respiratory tracts of the same subject. Significant differences in plaque morphology were observed between RSV subgroups. No correlations were found among plaque morphology and viral load. Plaque morphology did not correlate with disease severity. CONCLUSION Plaque morphology measures parameters that are viral-specific and independent of the human host. Morphologies vary between patients and are related to RSV subgroup. In HEp-2 cells, RSV plaque morphology appears unrelated to disease severity in RSV-infected children.
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Affiliation(s)
- Young-In Kim
- grid.267301.10000 0004 0386 9246Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee ,grid.413728.b0000 0004 0383 6997Children’s Foundation Research Institute at Le Bonheur Children’s Hospital, Memphis, Tennessee
| | - Ryan Murphy
- grid.267301.10000 0004 0386 9246Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee ,grid.413728.b0000 0004 0383 6997Children’s Foundation Research Institute at Le Bonheur Children’s Hospital, Memphis, Tennessee
| | - Sirshendu Majumdar
- grid.267301.10000 0004 0386 9246Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee ,grid.413728.b0000 0004 0383 6997Children’s Foundation Research Institute at Le Bonheur Children’s Hospital, Memphis, Tennessee
| | - Lisa G. Harrison
- grid.267301.10000 0004 0386 9246Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee ,grid.413728.b0000 0004 0383 6997Children’s Foundation Research Institute at Le Bonheur Children’s Hospital, Memphis, Tennessee
| | - Jody Aitken
- grid.413728.b0000 0004 0383 6997Children’s Foundation Research Institute at Le Bonheur Children’s Hospital, Memphis, Tennessee
| | - John P. DeVincenzo
- grid.267301.10000 0004 0386 9246Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee ,grid.413728.b0000 0004 0383 6997Children’s Foundation Research Institute at Le Bonheur Children’s Hospital, Memphis, Tennessee ,grid.267301.10000 0004 0386 9246Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee
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Flavivirus reverse genetic systems, construction techniques and applications: a historical perspective. Antiviral Res 2014; 114:67-85. [PMID: 25512228 PMCID: PMC7173292 DOI: 10.1016/j.antiviral.2014.12.007] [Citation(s) in RCA: 91] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 11/26/2014] [Accepted: 12/03/2014] [Indexed: 12/20/2022]
Abstract
The study of flaviviruses, which cause some of the most important emerging tropical and sub-tropical human arbovirus diseases, has greatly benefited from the use of reverse genetic systems since its first development for yellow fever virus in 1989. Reverse genetics technology has completely revolutionized the study of these viruses, making it possible to manipulate their genomes and evaluate the direct effects of these changes on their biology and pathogenesis. The most commonly used reverse genetics system is the infectious clone technology. Whilst flavivirus infectious clones provide a powerful tool, their construction as full-length cDNA molecules in bacterial vectors can be problematic, laborious and time consuming, because they are often unstable, contain unwanted induced substitutions and may be toxic for bacteria due to viral protein expression. The incredible technological advances that have been made during the past 30years, such as the use of PCR or new sequencing methods, have allowed the development of new approaches to improve preexisting systems or elaborate new strategies that overcome these problems. This review summarizes the evolution and major technical breakthroughs in the development of flavivirus reverse genetics technologies and their application to the further understanding and control of these viruses and their diseases.
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22
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Belikov SI, Kondratov IG, Potapova UV, Leonova GN. The relationship between the structure of the tick-borne encephalitis virus strains and their pathogenic properties. PLoS One 2014; 9:e94946. [PMID: 24740396 PMCID: PMC3989262 DOI: 10.1371/journal.pone.0094946] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2013] [Accepted: 03/20/2014] [Indexed: 12/11/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV) is transmitted to vertebrates by taiga or forest ticks through bites, inducing disease of variable severity. The reasons underlying these differences in the severity of the disease are unknown. In order to identify genetic factors affecting the pathogenicity of virus strains, we have sequenced and compared the complete genomes of 34 Far-Eastern subtype (FE) TBEV strains isolated from patients with different disease severity (Primorye, the Russian Far East). We analyzed the complete genomes of 11 human pathogenic strains isolated from the brains of dead patients with the encephalitic form of the disease (Efd), 4 strains from the blood of patients with the febrile form of TBE (Ffd), and 19 strains from patients with the subclinical form of TBE (Sfd). On the phylogenetic tree, pathogenic Efd strains formed two clusters containing the prototype strains, Senzhang and Sofjin, respectively. Sfd strains formed a third separate cluster, including the Oshima strain. The strains that caused the febrile form of the disease did not form a separate cluster. In the viral proteins, we found 198 positions with at least one amino acid residue substitution, of which only 17 amino acid residue substitutions were correlated with the variable pathogenicity of these strains in humans and they authentically differed between the groups. We considered the role of each amino acid substitution and assumed that the deletion of 111 amino acids in the capsid protein in combination with the amino acid substitutions R16K and S45F in the NS3 protease may affect the budding process of viral particles. These changes may be the major reason for the diminished pathogenicity of TBEV strains. We recommend Sfd strains for testing as attenuation vaccine candidates.
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MESH Headings
- 3' Untranslated Regions/genetics
- 5' Untranslated Regions/genetics
- Amino Acid Sequence
- Amino Acid Substitution
- Animals
- Base Sequence
- Capsid Proteins/chemistry
- Capsid Proteins/genetics
- China
- Encephalitis Viruses, Tick-Borne/classification
- Encephalitis Viruses, Tick-Borne/genetics
- Encephalitis Viruses, Tick-Borne/pathogenicity
- Encephalitis, Tick-Borne/blood
- Encephalitis, Tick-Borne/virology
- Genetic Structures
- Genome, Viral/genetics
- Geography
- Humans
- Models, Molecular
- Molecular Sequence Data
- Nucleic Acid Conformation
- Phylogeny
- Protein Structure, Tertiary
- RNA Helicases/chemistry
- RNA Helicases/genetics
- RNA, Viral/chemistry
- RNA, Viral/genetics
- Russia
- Sequence Homology, Amino Acid
- Serine Endopeptidases/chemistry
- Serine Endopeptidases/genetics
- Viral Nonstructural Proteins/chemistry
- Viral Nonstructural Proteins/genetics
- Virulence/genetics
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Affiliation(s)
- Sergei I. Belikov
- Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - Ilya G. Kondratov
- Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - Ulyana V. Potapova
- Limnological Institute, Siberian Branch, Russian Academy of Sciences, Irkutsk, Russia
| | - Galina N. Leonova
- Research Institute of Epidemiology and Microbiology, Siberian Branch, Russian Academy of Medical Sciences, Vladivostok, Russia
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23
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A critical determinant of neurological disease associated with highly pathogenic tick-borne flavivirus in mice. J Virol 2014; 88:5406-20. [PMID: 24574402 DOI: 10.1128/jvi.00421-14] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
UNLABELLED Tick-borne encephalitis virus (TBEV) and Omsk hemorrhagic fever virus (OHFV) are highly pathogenic tick-borne flaviviruses; TBEV causes neurological disease in humans, while OHFV causes a disease typically identified with hemorrhagic fever. Although TBEV and OHFV are closely related genetically, the viral determinants responsible for these distinct disease phenotypes have not been identified. In this study, chimeric viruses incorporating components of TBEV and OHFV were generated using infectious clone technology, and their pathological characteristics were analyzed in a mouse model to identify virus-specific determinants of disease. We found that only four amino acids near the C terminus of the NS5 protein were primarily responsible for the development of neurological disease. Mutation of these four amino acids had no effect on viral replication or histopathological features, including inflammatory responses, in mice. These findings suggest a critical role for NS5 in stimulating neuronal dysfunction and degeneration following TBEV infection and provide new insights into the molecular mechanisms underlying the pathogenesis of tick-borne flaviviruses. IMPORTANCE Tick-borne encephalitis virus (TBEV) and Omsk hemorrhagic fever virus (OHFV) belong to the tick-borne encephalitis serocomplex, genus Flavivirus, family Flaviviridae. Although TBEV causes neurological disease in humans while OHFV causes a disease typically identified with hemorrhagic fever. In this study, we investigated the viral determinants responsible for the different disease phenotypes using reverse genetics technology. We identified a cluster of only four amino acids in nonstructural protein 5 primarily involved in the development of neurological disease in a mouse model. Moreover, the effect of these four amino acids was independent of viral replication property and did not affect the formation of virus-induced lesions in the brain directly. These data suggest that these amino acids may be involved in the induction of neuronal dysfunction and degeneration in virus-infected neurons, ultimately leading to the neurological disease phenotype. These findings provide new insight into the molecular mechanisms of tick-borne flavivirus pathogenesis.
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24
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Luat LX, Tun MMN, Buerano CC, Aoki K, Morita K, Hayasaka D. Pathologic potential of variant clones of the oshima strain of far-eastern subtype tick-borne encephalitis virus. Trop Med Health 2014; 42:15-23. [PMID: 24808743 PMCID: PMC3965841 DOI: 10.2149/tmh.2013-27] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Accepted: 10/20/2013] [Indexed: 12/30/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV) is a zoonotic agent that causes acute central nervous system (CNS) disease in humans. We previously suggested that immune response in addition to CNS infection contribute to mouse mortality following TBEV infection. However, we did not examine the influence of virus variants in the previous study. Therefore, in this study, we investigated the biological and pathologic potentials of the variant clones in the TBEV Oshima strain. We isolated eight variant clones from the stock virus of the Oshima 5-10. These variants exhibited different plaque morphologies in BHK cells and pathogenic potentials in mice. Full sequences of viral genomes revealed that each of the variant clones except one had specific combinations of nucleotide and amino acid changes at certain positions different from the parent strain. We also showed that an amino acid substitution of Glu122→Gly in the E protein could have affected virus infection and replication in vivo, as well as the attenuated pathogenicity in mice. These data confirm the presence of virus variants or quasispecies from the parent strain. Further elucidation of the effect of each variant clone on immune responses such as the T-cell response is an important priority in the development of an effective vaccine and treatment strategies for tick-borne encephalitis.
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Affiliation(s)
- Le Xuan Luat
- Department of Virology, Institute of Tropical Medicine, Nagasaki University
| | - Mya Myat Ngwe Tun
- Department of Virology, Institute of Tropical Medicine, Nagasaki University
| | - Corazon C Buerano
- Department of Virology, Institute of Tropical Medicine, Nagasaki University
| | - Kotaro Aoki
- Department of Virology, Institute of Tropical Medicine, Nagasaki University
| | - Kouichi Morita
- Department of Virology, Institute of Tropical Medicine, Nagasaki University
| | - Daisuke Hayasaka
- Department of Virology, Institute of Tropical Medicine, Nagasaki University
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25
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Sakai M, Yoshii K, Sunden Y, Yokozawa K, Hirano M, Kariwa H. Variable region of the 3' UTR is a critical virulence factor in the Far-Eastern subtype of tick-borne encephalitis virus in a mouse model. J Gen Virol 2014; 95:823-835. [PMID: 24394696 DOI: 10.1099/vir.0.060046-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV) is a major arbovirus that causes thousands of cases of severe neurological illness in humans annually. However, virulence factors and pathological mechanisms of TBEV remain largely unknown. To identify the virulence factors, we constructed chimeric viruses between two TBEV strains of the Far-Eastern subtype, Sofjin-HO (highly pathogenic) and Oshima 5-10 (low pathogenic). The replacement of the coding region for the structural and non-structural proteins from Sofjin into Oshima showed a partial increase of the viral pathogenicity in a mouse model. Oshima-based chimeric viruses with the variable region of the 3' UTR of Sofjin, which had a deletion of 207 nt, killed 100 % of mice and showed almost the same virulence as Sofjin. Replacement of the variable region of the 3' UTR from Sofjin into Oshima did not increase viral multiplication in cultured cells and a mouse model at the early phase of viral entry into the brain. At the terminal phase of viral infection in mice, the virus titre of the Oshima-based chimeric virus with the variable region of the 3' UTR of Sofjin reached a level identical to that of Sofjin and showed a similar histopathological change in the brain tissue. This is the first report to show that the variable region of the 3' UTR is a critical virulence factor in mice. These findings encourage further study to understand the mechanisms of the pathogenicity of TBEV, and to develop preventative and therapeutic strategies for tick-borne encephalitis.
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Affiliation(s)
- Mizuki Sakai
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - Kentaro Yoshii
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - Yuji Sunden
- Laboratory of Comparative Pathology, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - Kana Yokozawa
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - Minato Hirano
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
| | - Hiroaki Kariwa
- Laboratory of Public Health, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060-0818, Japan
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26
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Abstract
Tick-borne encephalitis (TBE) virus is the most important human pathogen transmitted by ticks in Eurasia. Inactivated vaccines are available but require multiple doses and frequent boosters to induce and maintain immunity. Thus far, the goal of developing a safe, live attenuated vaccine effective after a single dose has remained elusive. Here we used a replication-defective (single-cycle) flavivirus platform, RepliVax, to generate a safe, single-dose TBE vaccine. Several RepliVax-TBE candidates attenuated by a deletion in the capsid gene were constructed using different flavivirus backbones containing the envelope genes of TBE virus. RepliVax-TBE based on a West Nile virus backbone (RV-WN/TBE) grew more efficiently in helper cells than candidates based on Langat E5, TBE, and yellow fever 17D backbones, and was found to be highly immunogenic and efficacious in mice. Live chimeric yellow fever 17D/TBE, Dengue 2/TBE, and Langat E5/TBE candidates were also constructed but were found to be underattenuated. RV-WN/TBE was demonstrated to be highly immunogenic in Rhesus macaques after a single dose, inducing a significantly more durable humoral immune response compared with three doses of a licensed, adjuvanted human inactivated vaccine. Its immunogenicity was not significantly affected by preexisting immunity against WN. Immunized monkeys were protected from a stringent surrogate challenge. These results support the identification of a single-cycle TBE vaccine with a superior product profile to existing inactivated vaccines, which could lead to improved vaccine coverage and control of the disease.
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27
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Pripuzova NS, Gmyl LV, Romanova LI, Tereshkina NV, Rogova YV, Terekhina LL, Kozlovskaya LI, Vorovitch MF, Grishina KG, Timofeev AV, Karganova GG. Exploring of primate models of tick-borne flaviviruses infection for evaluation of vaccines and drugs efficacy. PLoS One 2013; 8:e61094. [PMID: 23585873 PMCID: PMC3621963 DOI: 10.1371/journal.pone.0061094] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Accepted: 03/05/2013] [Indexed: 12/30/2022] Open
Abstract
Tick-borne encephalitis virus (TBEV) is one of the most prevalent and medically important tick-borne arboviruses in Eurasia. There are overlapping foci of two flaviviruses: TBEV and Omsk hemorrhagic fever virus (OHFV) in Russia. Inactivated vaccines exist only against TBE. There are no antiviral drugs for treatment of both diseases. Optimal animal models are necessary to study efficacy of novel vaccines and treatment preparations against TBE and relative flaviviruses. The models for TBE and OHF using subcutaneous inoculation were tested in Cercopithecus aethiops and Macaca fascicularis monkeys with or without prior immunization with inactivated TBE vaccine. No visible clinical signs or severe pathomorphological lesions were observed in any monkey infected with TBEV or OHFV. C. aethiops challenged with OHFV showed massive hemolytic syndrome and thrombocytopenia. Infectious virus or viral RNA was revealed in visceral organs and CNS of C. aethiops infected with both viruses; however, viremia was low. Inactivated TBE vaccines induced high antibody titers against both viruses and expressed booster after challenge. The protective efficacy against TBE was shown by the absence of virus in spleen, lymph nodes and CNS of immunized animals after challenge. Despite the absence of expressed hemolytic syndrome in immunized C. aethiops TBE vaccine did not prevent the reproduction of OHFV in CNS and visceral organs. Subcutaneous inoculation of M. fascicularis with two TBEV strains led to a febrile disease with well expressed viremia, fever, and virus reproduction in spleen, lymph nodes and CNS. The optimal terms for estimation of the viral titers in CNS were defined as 8-16 days post infection. We characterized two animal models similar to humans in their susceptibility to tick-borne flaviviruses and found the most optimal scheme for evaluation of efficacy of preventive and therapeutic preparations. We also identified M. fascicularis to be more susceptible to TBEV than C. aethiops.
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Affiliation(s)
- Natalia S. Pripuzova
- FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia
| | - Larissa V. Gmyl
- FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia
| | - Lidiya Iu. Romanova
- FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia
| | - Natalia V. Tereshkina
- FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia
| | - Yulia V. Rogova
- FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia
| | - Liubov L. Terekhina
- FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia
| | - Liubov I. Kozlovskaya
- FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia
| | - Mikhail F. Vorovitch
- FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia
| | - Karina G. Grishina
- FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia
| | - Andrey V. Timofeev
- FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia
| | - Galina G. Karganova
- FSBI Chumakov Institute of Poliomyelitis and Viral Encephalitides (IPVE) RAMS, Moscow, Russia
- * E-mail:
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28
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Frey S, Mossbrugger I, Altantuul D, Battsetseg J, Davaadorj R, Tserennorov D, Buyanjargal T, Otgonbaatar D, Zöller L, Speck S, Wölfel R, Dobler G, Essbauer S. Isolation, preliminary characterization, and full-genome analyses of tick-borne encephalitis virus from Mongolia. Virus Genes 2012; 45:413-25. [PMID: 22847274 DOI: 10.1007/s11262-012-0795-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2012] [Accepted: 07/20/2012] [Indexed: 10/28/2022]
Abstract
Tick-borne encephalitis virus (TBEV) causes one of the most important inflammatory diseases of the central nervous system, namely severe encephalitis in Europe and Asia. Since the 1980s tick-borne encephalitis is known in Mongolia with increasing numbers of human cases reported during the last years. So far, however, data on TBEV strains are still sparse. We herein report the isolation of a TBEV strain from Ixodes persulcatus ticks collected in Mongolia in 2010. Phylogenetic analysis of the E-gene classified this isolate as Siberian subtype of TBEV. The Mongolian TBEV strain showed differences in virus titers, plaque sizes, and growth properties in two human neuronal cell-lines. In addition, the 10,242 nucleotide long open-reading frame and the corresponding polyprotein sequence were revealed. The isolate grouped in the genetic subclade of the Siberian subtype. The strain Zausaev (AF527415) and Vasilchenko (AF069066) had 97 and 94 % identity on the nucleotide level. In summary, we herein describe first detailed data regarding TBEV from Mongolia. Further investigations of TBEV in Mongolia and adjacent areas are needed to understand the intricate dispersal of this virus.
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Affiliation(s)
- Stefan Frey
- Department of Virology & Rickettsiology, Bundeswehr Institute of Microbiology, Neuherbergstraße 11, Munich, Germany
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29
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Rumyantsev AA, Giel-Moloney M, Liu Y, Gao QS, Zhang ZX, Catalan J, Frolov I, Almond J, Kleanthous H, Pugachev KV. Characterization of the RepliVax platform for replication-defective flavivirus vaccines. Vaccine 2011; 29:5184-94. [DOI: 10.1016/j.vaccine.2011.05.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 05/06/2011] [Accepted: 05/11/2011] [Indexed: 02/06/2023]
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30
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Engel AR, Rumyantsev AA, Maximova OA, Speicher JM, Heiss B, Murphy BR, Pletnev AG. The neurovirulence and neuroinvasiveness of chimeric tick-borne encephalitis/dengue virus can be attenuated by introducing defined mutations into the envelope and NS5 protein genes and the 3' non-coding region of the genome. Virology 2010; 405:243-52. [PMID: 20594569 DOI: 10.1016/j.virol.2010.06.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2010] [Revised: 05/17/2010] [Accepted: 06/07/2010] [Indexed: 12/30/2022]
Abstract
Tick-borne encephalitis (TBE) is a severe disease affecting thousands of people throughout Eurasia. Despite the use of formalin-inactivated vaccines in endemic areas, an increasing incidence of TBE emphasizes the need for an alternative vaccine that will induce a more durable immunity against TBE virus (TBEV). The chimeric attenuated virus vaccine candidate containing the structural protein genes of TBEV on a dengue virus genetic background (TBEV/DEN4) retains a high level of neurovirulence in both mice and monkeys. Therefore, attenuating mutations were introduced into the envelope (E(315)) and NS5 (NS5(654,655)) proteins, and into the 3' non-coding region (Delta30) of TBEV/DEN4. The variant that contained all three mutations (vDelta30/E(315)/NS5(654,655)) was significantly attenuated for neuroinvasiveness and neurovirulence and displayed a reduced level of replication and virus-induced histopathology in the brains of mice. The high level of safety in the central nervous system indicates that vDelta30/E(315)/NS5(654,655) should be further evaluated as a TBEV vaccine.
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Affiliation(s)
- Amber R Engel
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
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31
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Blaney JE, Durbin AP, Murphy BR, Whitehead SS. Targeted mutagenesis as a rational approach to dengue virus vaccine development. Curr Top Microbiol Immunol 2010; 338:145-58. [PMID: 19802584 PMCID: PMC3405492 DOI: 10.1007/978-3-642-02215-9_11] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The recombinant dengue virus type 4 (rDEN4) vaccine candidate, rDEN4Delta30, was found to be highly infectious, immunogenic and safe in human volunteers. At the highest dose (10(5) PFU) evaluated in volunteers, 25% of the vaccinees had mild elevations in liver enzymes that were rarely seen at lower doses. Here, we describe the generation and selection of additional mutations that were introduced into rDEN4Delta30 to further attenuate the virus in animal models and ultimately human vaccinees. Based on the elevated liver enzymes associated with the 10(5) PFU dose of rDEN4Delta30 and the known involvement of liver infection in dengue virus pathogenesis, a large panel of mutant viruses was screened for level of replication in the HuH-7 human hepatoma cell line, a surrogate for human liver cells and selected viruses were further analyzed for level of viremia in SCID-HuH-7 mice. It was hypothesized that rDEN4Delta30 derivatives with restricted replication in vitro and in vivo in HuH-7 human liver cells would be restricted in replication in the liver of vaccinees. Two mutations identified by this screen, NS3 4995 and NS5 200,201, were separately introduced into rDEN4Delta30 and found to further attenuate the vaccine candidate for SCID-HuH-7 mice and rhesus monkeys while retaining sufficient immunogenicity in rhesus monkeys to confer protection. In humans, the rDEN4Delta30-200,201 vaccine candidate administered at 10(5) PFU exhibited greatly reduced viremia, high infectivity and lacked liver toxicity while inducing serum neutralizing antibody at a level comparable to that observed in volunteers immunized with rDEN4Delta30. Clinical studies of rDEN4Delta30-4995 are ongoing.
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Affiliation(s)
- Joseph E Blaney
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 33 North Drive, Room 3W10A, Bethesda, MD 20892-3203, USA
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32
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Rumyantsev AA, Zhang ZX, Gao QS, Moretti N, Brown N, Kleanthous H, Delagrave S, Guirakhoo F, Collett MS, Pugachev KV. Direct random insertion of an influenza virus immunologic determinant into the NS1 glycoprotein of a vaccine flavivirus. Virology 2010; 396:329-38. [DOI: 10.1016/j.virol.2009.10.033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2009] [Revised: 10/13/2009] [Accepted: 10/20/2009] [Indexed: 01/19/2023]
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33
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Barker WC, Mazumder R, Vasudevan S, Sagripanti JL, Wu CH. Sequence signatures in envelope protein may determine whether flaviviruses produce hemorrhagic or encephalitic syndromes. Virus Genes 2009; 39:1-9. [PMID: 19283462 DOI: 10.1007/s11262-009-0343-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2008] [Accepted: 02/23/2009] [Indexed: 01/09/2023]
Abstract
We analyzed the envelope proteins in pathogenic flaviviruses to determine whether there are sequence signatures associated with the tendency of viruses to produce hemorrhagic disease (H-viruses) or encephalitis (E-viruses). We found that, at the position corresponding to the glycosylated Asn-67 in dengue virus, asparagine (Asn) occurs in all seven viral species that cause hemorrhagic disease in humans. Furthermore, Asn was extremely rare at position 67 in six flaviviruses that cause encephalitis, being replaced by Asp in four of them. Of the 3,246 sequences from H- and E-viruses, we found that 2,916 sequences (90%) contained Asn in position 67 for H-viruses or Asp in position 67 for E-viruses. The change from Asn-67 that is prevalent in H-viruses to Asp-67 (common in E-viruses) contributes to a stronger electrostatically negative surface in the E-viruses as compared to the H-viruses. These findings should help predicting the disease potential of emerging and re-emerging flaviviruses and understanding the relationship between protein structure and disease outcome.
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Affiliation(s)
- Winona C Barker
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, DC 20007, USA
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34
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Sakata M, Komase K, Nakayama T. Histidine at position 1042 of the p150 region of a KRT live attenuated rubella vaccine strain is responsible for the temperature sensitivity. Vaccine 2008; 27:234-42. [PMID: 18996422 DOI: 10.1016/j.vaccine.2008.10.049] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2008] [Revised: 10/02/2008] [Accepted: 10/19/2008] [Indexed: 11/27/2022]
Abstract
The Japanese live attenuated KRT rubella vaccine strain has a temperature sensitivity (ts) phenotype. The objective of this study is to identify the region responsible for this phenotype. Genomic sequences of the KRT strain and the wild-type strain (RVi/Matsue.JPN/68) with the non-ts phenotype were investigated and reverse genetic systems (RG) for these strains were developed. The ts phenotype of KRT varied drastically on replacement of the p150 gene (encoding a methyltransferase and a nonstructural protease). Analysis of four chimeric viruses showed the region responsible for the ts phenotype to be located between Bsm I and Nhe I sites (genome position 2803-3243). There were two amino acid differences at positions 1007 and 1042. Mutations were introduced into the KRT cDNA clone, designated G1007D, H1042Y and G1007D-H1042Y. H1042Y and G1007D-H1042Y grew well at a restrictive temperature with a 100-fold higher titer than G1007D and the KRT strain, but a 10-fold lower titer than RVi/Matsue.JPN/68. Since the growth of H1042Y was not completely the same as that of the wild-type strain at the restrictive temperature, we also assessed whether other genomic regions have an additive effect with H1042Y on the ts phenotype. H1042Y-RViM SP having structural proteins of RVi/Matsue.JPN/68 grew better than H1042Y, similar to RVi/Matsue.JPN/68. Thus, we concluded that one mutation, of the histidine at position 1042 of p150, was essential for the ts phenotype of the KRT strain, and structural proteins of KRT had an additive effect with H1042Y on the ts phenotype.
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Affiliation(s)
- Masafumi Sakata
- Laboratory of Viral Infection I, Kitasato Institute for Life Sciences, 5-9-1 Shirokane, Minato-ku, 108-8641 Tokyo, Japan
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35
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Attenuated West Nile viruses bearing 3′SL and envelope gene substitution mutations. Vaccine 2008; 26:5981-8. [DOI: 10.1016/j.vaccine.2008.08.064] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Revised: 08/19/2008] [Accepted: 08/25/2008] [Indexed: 11/22/2022]
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36
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Mitzel DN, Best SM, Masnick MF, Porcella SF, Wolfinbarger JB, Bloom ME. Identification of genetic determinants of a tick-borne flavivirus associated with host-specific adaptation and pathogenicity. Virology 2008; 381:268-76. [PMID: 18823640 DOI: 10.1016/j.virol.2008.08.030] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2008] [Revised: 08/05/2008] [Accepted: 08/19/2008] [Indexed: 01/12/2023]
Abstract
Tick-borne flaviviruses are maintained in nature in an enzootic cycle involving a tick vector and a vertebrate host. Thus, the virus replicates in two disparate hosts, each providing selective pressures that can influence virus replication and pathogenicity. To identify viral determinants associated with replication in the individual hosts, plaque purified Langat virus (TP21pp) was adapted to growth in mouse or tick cell lines to generate two virus variants, MNBp20 and ISEp20, respectively. Virus adaptation to mouse cells resulted in four amino acid changes in MNBp20 relative to TP21pp, occurring in E, NS4A and NS4B. A comparison between TP21pp and ISEp20 revealed three amino acid modifications in M, NS3 and NS4A of ISEp20. ISEp20, but not MNBp20, was attenuated following intraperitoneal inoculation of mice. Following isolation from mice brains, additional mutations reproducibly emerged in E and NS3 of ISEp20 that were possibly compensatory for the initial adaptation to tick cells. Thus, our data implicate a role for E, M, NS3, NS4A and NS4B in host adaptation and pathogenicity of tick-borne flaviviruses.
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Affiliation(s)
- Dana N Mitzel
- Laboratory of Virology, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 903 South Fourth Street, Hamilton, MT 59840, USA.
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37
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Jia Y, Moudy RM, Dupuis AP, Ngo KA, Maffei JG, Jerzak GVS, Franke MA, Kauffman EB, Kramer LD. Characterization of a small plaque variant of West Nile virus isolated in New York in 2000. Virology 2007; 367:339-47. [PMID: 17617432 PMCID: PMC2190729 DOI: 10.1016/j.virol.2007.06.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Revised: 04/07/2007] [Accepted: 06/07/2007] [Indexed: 11/29/2022]
Abstract
A small-plaque variant (SP) of West Nile virus (WNV) was isolated in Vero cell culture from kidney tissue of an American crow collected in New York in 2000. The in vitro growth of the SP and parental (WT) strains was characterized in mammalian (Vero), avian (DF-1 and PDE), and mosquito (C6/36) cells. The SP variant replicated less efficiently than did the WT in Vero cells. In avian cells, SP growth was severely restricted at high temperatures, suggesting that the variant is temperature sensitive. In mosquito cells, growth of SP and WT was similar, but in vivo in Culex pipiens (L.) there were substantial differences. Relative to WT, SP exhibited reduced replication following intrathoracic inoculation and lower infection, dissemination, and transmission rates following oral infection. Analysis of the full length sequence of the SP variant identified sequence differences which led to only two amino acid substitutions relative to WT, prM P54S and NS2A V61A.
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Affiliation(s)
- Yongqing Jia
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York 12159
| | - Robin M. Moudy
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York 12159
| | - Alan P. Dupuis
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York 12159
| | - Kiet A. Ngo
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York 12159
| | - Joseph G. Maffei
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York 12159
| | - Greta V. S. Jerzak
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York 12159
| | - Mary A. Franke
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York 12159
| | - Elizabeth B. Kauffman
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York 12159
| | - Laura D. Kramer
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York 12159
- Department of Biomedical Sciences, School of Public Health, State University of New York at Albany, Albany, New York 12201
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Pletnev AG, Swayne DE, Speicher J, Rumyantsev AA, Murphy BR. Chimeric West Nile/dengue virus vaccine candidate: preclinical evaluation in mice, geese and monkeys for safety and immunogenicity. Vaccine 2006; 24:6392-404. [PMID: 16831498 DOI: 10.1016/j.vaccine.2006.06.008] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Revised: 05/31/2006] [Accepted: 06/07/2006] [Indexed: 11/28/2022]
Abstract
A live attenuated virus vaccine is being developed to protect against West Nile virus (WN) disease in humans. Previously, it was found that chimeric West Nile/dengue viruses (WN/DEN4 and WN/DEN4Delta30) bearing the membrane precursor and envelope protein genes of WN on a backbone of dengue type 4 virus (DEN4) with or without a deletion of 30 nucleotides (Delta30) in the 3' noncoding region of the DEN4 part of the chimeric genome were attenuated and efficacious in mice and monkeys against WN challenge. Here, we report the generation of a clinical lot of WN/DEN4Delta30 virus and its further preclinical evaluation for safety and immunogenicity in mice, geese and monkeys. The vaccine candidate had lost neuroinvasiveness in highly sensitive immunodeficient mice inoculated intraperitoneally and had greatly reduced neurovirulence in suckling mice inoculated intracerebrally (IC). Compared to the wild-type WN parent, the chimeric virus was highly restricted in replication in both murine and human neuroblastoma cells as well as in brains of suckling mice. The WN/DEN4Delta30 virus failed to infect geese, indicating that chimerization of WN with DEN4 completely attenuated WN for this avian host. This observation suggests that the WN/DEN4 chimeric viruses would be restricted in their ability to be transmitted from vaccinees to domestic or wild birds. In monkeys, the WN/DEN4Delta30 vaccine candidate was highly immunogenic despite its low level of replication with undetectable viremia. Furthermore, the WN/DEN4Delta30 vaccine virus was safe and readily induced neutralizing antibodies against WN in monkeys immune to each of the four serotypes of dengue virus. These studies confirm the attenuation of WN/DEN4Delta30 for non-human primates, including dengue-immune monkeys, and demonstrate both a highly restricted replication (>10(8)-fold decrease) in the brain of mice inoculated IC and an absence of infectivity for birds, findings that indicate this vaccine should be safe for both the recipient and the environment.
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Affiliation(s)
- Alexander G Pletnev
- Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-8133, USA.
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