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Tang WD, Zhu WY, Tang HL, Zhao P, Zhao LJ. Engagement of AKT and ERK signaling pathways facilitates infection of human neuronal cells with West Nile virus. J Virus Erad 2024; 10:100368. [PMID: 38601702 PMCID: PMC11004658 DOI: 10.1016/j.jve.2024.100368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 03/23/2024] [Accepted: 03/25/2024] [Indexed: 04/12/2024] Open
Abstract
West Nile virus (WNV) is an important neurotropic virus that accounts for the emergence of human arboviral encephalitis and meningitis. The interaction of WNV with signaling pathways plays a key role in controlling WNV infection. We have investigated the roles of the AKT and ERK pathways in supporting WNV propagation and modulating the inflammatory response following WNV infection. WNV established a productive infection in neuronal cell lines originated from human and mouse. Expression of IL-11 and TNF-α was markedly up-regulated in the infected human neuronal cells, indicating elicitation of inflammation response upon WNV infection. WNV incubation rapidly activated signaling cascades of AKT (AKT-S6-4E-BP1) and ERK (MEK-ERK-p90RSK) pathways. Treatment with AKT inhibitor MK-2206 or MEK inhibitor U0126 abrogated WNV-induced AKT or ERK activation. Strong activation of AKT and ERK signaling pathways could be detectable at 24 h after WNV infection, while such activation was abolished at 48 h post infection. U0126 treatment or knockdown of ERK expression significantly increased WNV RNA levels and viral titers and efficiently decreased IL-11 production induced by WNV, suggesting the involvement of ERK pathway in WNV propagation and IL-11 induction. MK-2206 treatment enhanced WNV RNA replication accompanied with a moderate decrease in IL-11 production. These results demonstrate that engagement of AKT and ERK signaling pathways facilitates viral infection and may be implicated in WNV pathogenesis.
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Affiliation(s)
- Wan-Da Tang
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Faculty of Naval Medicine, Naval Medical University, 200433, Shanghai, China
| | - Wei-Yang Zhu
- The 16th Student Brigade, College of Basic Medicine, Naval Medical University, 200433, Shanghai, China
| | - Hai-Lin Tang
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Faculty of Naval Medicine, Naval Medical University, 200433, Shanghai, China
| | - Ping Zhao
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Faculty of Naval Medicine, Naval Medical University, 200433, Shanghai, China
| | - Lan-Juan Zhao
- Department of Microbiology, Shanghai Key Laboratory of Medical Biodefense, Faculty of Naval Medicine, Naval Medical University, 200433, Shanghai, China
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2
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Calpain drives pyroptotic vimentin cleavage, intermediate filament loss, and cell rupture that mediates immunostimulation. Proc Natl Acad Sci U S A 2019; 116:5061-5070. [PMID: 30796192 DOI: 10.1073/pnas.1818598116] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Pyroptosis is an inflammatory form of programmed cell death following cellular damage or infection. It is a lytic process driven by gasdermin D-mediated cellular permeabilization and presumed osmotic forces thought to induce swelling and rupture. We found that pyroptotic cells do not spontaneously rupture in culture but lose mechanical resilience. As a result, cells were susceptible to rupture by extrinsic forces, such as shear stress or compression. Cell analyses revealed that all major cytoskeleton components were disrupted during pyroptosis and that sensitivity to rupture was calpain-dependent and linked with cleavage of vimentin and loss of intermediate filaments. Moreover, while release of lactate dehydrogenase (LDH), HMGB1, and IL-1β occurred without rupture, rupture was required for release of large inflammatory stimuli-ASC specks, mitochondria, nuclei, and bacteria. Importantly, supernatants from ruptured cells were more immunostimulatory than those from nonruptured cells. These observations reveal undiscovered cellular events occurring during pyroptosis, define the mechanisms driving pyroptotic rupture, and highlight the immunologic importance of this event.
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Wang J, Lei CQ, Ji Y, Zhou H, Ren Y, Peng Q, Zeng Y, Jia Y, Ge J, Zhong B, Li Y, Wei J, Shu HB, Zhu Q. Duck Tembusu Virus Nonstructural Protein 1 Antagonizes IFN-β Signaling Pathways by Targeting VISA. THE JOURNAL OF IMMUNOLOGY 2016; 197:4704-4713. [PMID: 27821666 DOI: 10.4049/jimmunol.1502317] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 10/06/2016] [Indexed: 11/19/2022]
Abstract
Duck Tembusu virus (DTMUV) is an emergent infectious pathogen that has caused severe disease in ducks and huge economic losses to the poultry industry in China since 2009. Previously, we showed that DTMUV inhibits IFN-β induction early in infection; however, the mechanisms of the inhibition of innate immune responses remain poorly understood. In this study, we screened DTMUV-encoded structural and nonstructural proteins using reporter assays and found that DTMUV NS1 markedly suppressed virus-triggered IFN-β expression by inhibiting retinoic acid-inducible gene I-like receptor signaling. Moreover, we found that DTMUV NS1 specifically interacted with the C-terminal domain of virus-induced signaling adaptor and impaired the association of retinoic acid-inducible gene I or melanoma differentiation-associated gene 5 and virus-induced signaling adaptor, thereby downregulating the retinoic acid-inducible gene I-like receptor-mediated signal transduction and cellular antiviral responses, leading to evasion of the innate immune response. Together, our findings reveal a novel mechanism manipulated by DTMUV to circumvent the host antiviral immune response.
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Affiliation(s)
- Junyong Wang
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, People's Republic of China
| | - Cao-Qi Lei
- College of Life Sciences, Medical Research Institute, Wuhan University, Wuhan 430072, People's Republic of China;
| | - Yanhong Ji
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, People's Republic of China
| | - Hongbo Zhou
- State Key Laboratory of Agriculture Microbiology, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan 430070, People's Republic of China
| | - Yujie Ren
- College of Life Sciences, Medical Research Institute, Wuhan University, Wuhan 430072, People's Republic of China
| | - Qianqian Peng
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, People's Republic of China
| | - Yan Zeng
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, People's Republic of China
| | - Yane Jia
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, People's Republic of China
| | - Jinying Ge
- State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, People's Republic of China; and
| | - Bo Zhong
- College of Life Sciences, Medical Research Institute, Wuhan University, Wuhan 430072, People's Republic of China
| | - Yu Li
- College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, People's Republic of China
| | - Jianzhong Wei
- College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, People's Republic of China
| | - Hong-Bing Shu
- College of Life Sciences, Medical Research Institute, Wuhan University, Wuhan 430072, People's Republic of China
| | - Qiyun Zhu
- State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou 730046, People's Republic of China;
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4
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Miorin L, Maiuri P, Marcello A. Visual detection of Flavivirus RNA in living cells. Methods 2016; 98:82-90. [PMID: 26542763 PMCID: PMC7129942 DOI: 10.1016/j.ymeth.2015.11.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 10/29/2015] [Accepted: 11/01/2015] [Indexed: 12/24/2022] Open
Abstract
Flaviviruses include a wide range of important human pathogens delivered by insects or ticks. These viruses have a positive-stranded RNA genome that is replicated in the cytoplasm of the infected cell. The viral RNA genome is the template for transcription by the virally encoded RNA polymerase and for translation of the viral proteins. Furthermore, the double-stranded RNA intermediates of viral replication are believed to trigger the innate immune response through interaction with cytoplasmic cellular sensors. Therefore, understanding the subcellular distribution and dynamics of Flavivirus RNAs is of paramount importance to understand the interaction of the virus with its cellular host, which could be of insect, tick or mammalian, including human, origin. Recent advances on the visualization of Flavivirus RNA in living cells together with the development of methods to measure the dynamic properties of viral RNA are reviewed and discussed in this essay. In particular the application of bleaching techniques such as fluorescence recovery after photobleaching (FRAP) and fluorescence loss in photobleaching (FLIP) are analysed in the context of tick-borne encephalitis virus replication. Conclusions driven by this approached are discussed in the wider context Flavivirus infection.
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MESH Headings
- Animals
- Cell Line
- Cricetinae
- Encephalitis Viruses, Tick-Borne/genetics
- Encephalitis Viruses, Tick-Borne/metabolism
- Encephalitis Viruses, Tick-Borne/ultrastructure
- Fluorescence Recovery After Photobleaching
- Fluorescent Dyes/chemistry
- Gene Expression Regulation, Viral
- Host-Pathogen Interactions
- Humans
- Molecular Imaging/methods
- RNA, Messenger/chemistry
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Viral/chemistry
- RNA, Viral/genetics
- RNA, Viral/metabolism
- Recombinant Fusion Proteins/genetics
- Recombinant Fusion Proteins/metabolism
- Staining and Labeling/methods
- Ticks/virology
- Transcription, Genetic
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Affiliation(s)
- Lisa Miorin
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Paolo Maiuri
- IFOM - Istituto FIRC di Oncologia Molecolare, via Adamello 16, 20139 Milan, Italy
| | - Alessandro Marcello
- Laboratory of Molecular Virology, International Centre for Genetic Engineering and Biotechnology (ICGEB), Padriciano 99, 34149 Trieste, Italy.
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Chugh PE, Damania BA, Dittmer DP. Toll-like receptor-3 is dispensable for the innate microRNA response to West Nile virus (WNV). PLoS One 2014; 9:e104770. [PMID: 25127040 PMCID: PMC4134228 DOI: 10.1371/journal.pone.0104770] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 07/16/2014] [Indexed: 12/28/2022] Open
Abstract
The innate immune response to West Nile virus (WNV) infection involves recognition through toll-like receptors (TLRs) and RIG-I-like receptors (RLRs), leading to establishment of an antiviral state. MiRNAs (miRNAs) have been shown to be reliable biomarkers of TLR activation. Here, we sought to evaluate the contribution of TLR3 and miRNAs to the host response to WNV infection. We first analyzed HEK293-NULL and HEK293-TLR3 cells for changes in the innate immune response to infection. The presence of TLR3 did not seem to affect WNV load, infectivity or phosphorylation of IRF3. Analysis of experimentally validated NFκB-responsive genes revealed a WNV-induced signature largely independent of TLR3. Since miRNAs are involved in viral pathogenesis and the innate response to infection, we sought to identify changes in miRNA expression upon infection in the presence or absence of TLR3. MiRNA profiling revealed 70 miRNAs induced following WNV infection in a TLR3-independent manner. Further analysis of predicted gene targets of WNV signature miRNAs revealed genes highly associated with pathways regulating cell death, viral pathogenesis and immune cell trafficking.
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Affiliation(s)
- Pauline E. Chugh
- Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Blossom A. Damania
- Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Dirk P. Dittmer
- Department of Microbiology and Immunology, Lineberger Comprehensive Cancer Center, Center for AIDS Research, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
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6
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Neal JW. Flaviviruses are neurotropic, but how do they invade the CNS? J Infect 2014; 69:203-15. [PMID: 24880028 DOI: 10.1016/j.jinf.2014.05.010] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Revised: 05/10/2014] [Accepted: 05/19/2014] [Indexed: 12/17/2022]
Abstract
Flaviruses (FV) are RNA viruses carried by mosquitoes. Neurological signs including acute encephalitis, meningitis and acute flaccid paralysis develop in a small percentage of infected individuals; long term sequlae are, Parkinsonism, dystonias and cognitive changes. FV neuroinfection is neurotropic involving subcortical nuclei (substantia nigra and thalamus) anterior horn neurons and neocortex. Glycosylation of the FV E envelope protein is one determinant of neuroinvasion, increasing both axonal and trans-epithelial transportation. Neutralizing antibodies against the E and NS proteins prevents FV uptake into several cell types, including axons. CD8+ T cells are vital for clearance of WNF infected cells from the CNS, whereas TLR-3 and TLR-7 mediated anti-virus response through increased serum inflammatory cytokines to disrupt the BBB providing infected leucocytes and free virus access to the CNS (so called Trojan horse) Cellular virus attachment factors, promoting FV cell entry are widely distributed and include DC-SIGN (that detects complex carbohydrate molecules); Glycosamino glycans (GAG), Heparan sulphate(HSPG) Semaphorin 7A, Low Density Lipid receptors (LDLR); these are not FV specific virus entry receptors. The FV also crosses epithelial and endothelial barriers by disrupting Tight Junction complexes to increase BBB permeability. This review describes the multiple pathways responsible for the neuroinvasive properties of the Flaviviruses.
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Affiliation(s)
- J W Neal
- Institute of Infection and Immunity, Henry Wellcome Building, University Hospital of Wales, Cardiff University, Cardiff CF14 4XN, United Kingdom.
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7
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Carrithers MD. Innate immune viral recognition: relevance to CNS infections. HANDBOOK OF CLINICAL NEUROLOGY 2014; 123:215-23. [PMID: 25015487 DOI: 10.1016/b978-0-444-53488-0.00009-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Innate immune responses mediated by mononuclear phagocytes represent the initial host response to acute viral infection. PRRs, including TLRs, retinoic RLRs,and NOD-like receptors, recognize viral nucleic acid and localized injury signals to initiate proinflammatory responses and activation of adaptive immunity. These responses are host- and viral-dependent. Neurotropic viruses, such as HSV, West Nile virus, and HIV activate and evade innate immune signaling mechanisms by distinct mechanisms. These highly complex pathogen-host interactions determine establishment of infection, severity of clinical disease, development of chronic inflammatory processes, and success of vaccination strategies.
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Affiliation(s)
- Michael D Carrithers
- Neurology Service, William S. Middleton Memorial Veterans Hospital, and Department of Neurology, University of Wisconsin, Madison, WI, USA.
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Canine hepacivirus NS3 serine protease can cleave the human adaptor proteins MAVS and TRIF. PLoS One 2012; 7:e42481. [PMID: 22870331 PMCID: PMC3411667 DOI: 10.1371/journal.pone.0042481] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Accepted: 07/05/2012] [Indexed: 01/28/2023] Open
Abstract
Canine hepacivirus (CHV) was recently identified in domestic dogs and horses. The finding that CHV is genetically the virus most closely related to hepatitis C virus (HCV) has raised the question of whether HCV might have evolved as the result of close contact between dogs and/or horses and humans. The aim of this study was to investigate whether the NS3/4A serine protease of CHV specifically cleaves human mitochondrial antiviral signaling protein (MAVS) and Toll-IL-1 receptor domain-containing adaptor inducing interferon-beta (TRIF). The proteolytic activity of CHV NS3/4A was evaluated using a bacteriophage lambda genetic screen. Human MAVS- and TRIF-specific cleavage sites were engineered into the lambda cI repressor. Upon infection of Escherichia coli cells coexpressing these repressors and a CHV NS3/4A construct, lambda phage replicated up to 2000-fold more efficiently than in cells expressing a CHV protease variant carrying the inactivating substitution S139A. Comparable results were obtained when several HCV NS3/4A constructs of genotype 1b were assayed. This indicates that CHV can disrupt the human innate antiviral defense signaling pathway and suggests a possible evolutionary relationship between CHV and HCV.
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9
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Formation of membrane-defined compartments by tick-borne encephalitis virus contributes to the early delay in interferon signaling. Virus Res 2012; 163:660-6. [DOI: 10.1016/j.virusres.2011.11.020] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Revised: 11/21/2011] [Accepted: 11/23/2011] [Indexed: 12/12/2022]
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10
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Ling ZL, Combes V, Grau GE, King NJC. Microparticles as immune regulators in infectious disease - an opinion. Front Immunol 2011; 2:67. [PMID: 22566856 PMCID: PMC3342294 DOI: 10.3389/fimmu.2011.00067] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2011] [Accepted: 11/11/2011] [Indexed: 01/06/2023] Open
Abstract
Despite their clear relationship to immunology, few existing studies have examined the potential role of microparticles (MP) in infectious disease. MP have a different size range from exosomes and apoptotic bodies, with which they are often grouped and arise by different mechanisms in association with inflammatory cytokine action or stress on the source cell. Infection with pathogens usually leads to the expression of a range of inflammatory cytokines and chemokines, as well as significant stress in both infected and uninfected cells. It is thus reasonable to infer that infection-associated inflammation also leads to MP production. MP are produced by most of the major cell types in the immune system, and appear to be involved at both innate and adaptive levels, potentially serving different functions in each. Thus, they do not appear to have a universal function; instead their functions are source- or stimulus-dependent, although likely to be primarily either pro- or anti-inflammatory. We argue that in infectious diseases, MP may be able to deliver antigen, derived from the biological cargo acquired from their cells of origin, to antigen-presenting cells. Another potential benefit of MP would be to transfer and/or disseminate phenotype and function to target cells. However, MP may also potentially be manipulated, particularly by intracellular pathogens, for survival advantage.
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Affiliation(s)
- Zheng Lung Ling
- Discipline of Pathology, Bosch Institute, School of Medical Sciences, Sydney Medical School, University of Sydney Sydney, NSW, Australia
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11
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Abstract
Viruses are the most abundant and diverse pathogens challenging the host immune system, and as such are a severe threat to human health. To this end, viruses have evolved multiple strategies to evade and subvert the host immune response. Host-pathogen interactions are usually initiated via recognition of pathogen-associated molecular patterns (PAMPs) by host sensors known as pattern recognition receptors (PRRs), which include, Toll-like receptors (TLRs), RIG-I-like receptors (RLRs), NOD-like receptors (NLRs) and DNA receptors. Effective sensing of PAMPs rapidly triggers host immune responses, via activation of complex signalling pathways that culminates in the induction of inflammatory responses and the eradication of pathogens. Activation of the nuclear factor-κB (NF-κB) transcription pathway is crucial for the immediate early step of immune activation. This review discusses the recent evidence describing a variety of viral effectors that have been shown to prevent NF-κB signalling. Most of these viral effectors can be broadly classified into three categories based on the site of inhibition within the NF-κB pathway, that is, at the (i) TLRs, (ii) IKK complex or (iii) the transcriptional level.
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Affiliation(s)
- Gaëlle Le Negrate
- Institute of Medical Microbiology and Hospital Hygiene, Heinrich Heine University, Düsseldorf, Germany.
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12
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Development time of IgG antibodies to West Nile virus. Arch Virol 2011; 156:1661-3. [DOI: 10.1007/s00705-011-1014-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2011] [Accepted: 04/29/2011] [Indexed: 11/27/2022]
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13
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Delayed cytosolic exposure of Japanese encephalitis virus double-stranded RNA impedes interferon activation and enhances viral dissemination in porcine cells. J Virol 2011; 85:6736-49. [PMID: 21525349 DOI: 10.1128/jvi.00233-11] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Interferon is a principal component of the host antiviral defense system. In this study, abortive focus formation by Japanese encephalitis virus (JEV) in primate cells was accompanied by early interferon induction, while productive focus formation in porcine cells was associated with a late interferon response. Neutralization antibodies against interferon relieved the restricted infection in primate cells, and increasingly larger foci were generated as treatment with exogenous interferon was delayed, thereby establishing a solid correlation between interferon response and viral dissemination. However, delayed interferon induction in JEV-infected porcine cells occurred in the absence of active inhibition by the virus. We further demonstrated that JEV mediates interferon activation through double-stranded RNA and cytosolic pattern recognition receptors. Immunofluorescence and subcellular fractionation studies revealed that double-stranded RNA is concealed in intracellular membranes at an early phase of infection but eventually appears in the cytosol at later periods, which could then allow detection by cytosolic pattern recognition receptors. Interestingly, cytosolic exposure of double-stranded RNA was delayed in porcine cells compared to primate cells, independent of total double-stranded RNA levels and in correlation with the timing of the interferon response. Furthermore, when double-stranded RNA was artificially introduced into the cytosol of porcine cells, more rapid and robust interferon activation was triggered than in viral infection. Thus, cytosolic exposure of JEV double-stranded RNA is imperative for interferon induction, but in cell lines (e.g., porcine cells) with delayed emergence of cytosolic double-stranded RNA, the interferon response is late and viral dissemination is consequently enhanced.
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Domingo-Gil E, Toribio R, Nájera JL, Esteban M, Ventoso I. Diversity in viral anti-PKR mechanisms: a remarkable case of evolutionary convergence. PLoS One 2011; 6:e16711. [PMID: 21311764 PMCID: PMC3032782 DOI: 10.1371/journal.pone.0016711] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2010] [Accepted: 01/11/2011] [Indexed: 12/22/2022] Open
Abstract
Most viruses express during infection products that prevent or neutralize the effect of the host dsRNA activated protein kinase (PKR). Translation of Sindbis virus (SINV) mRNA escapes to PKR activation and eIF2 phosphorylation in infected cells by a mechanism that requires a stem loop structure in viral 26S mRNA termed DLP to initiate translation in the absence of functional eIF2. Unlike the rest of viruses tested, we found that Alphavirus infection allowed a strong PKR activation and eIF2α phosphorylation in vitro and in infected animals so that the presence of DLP structure in mRNA was critical for translation and replication of SINV. Interestingly, infection of MEFs with some viruses that express PKR inhibitors prevented eIF2α phosphorylation after superinfection with SINV, suggesting that viral anti-PKR mechanisms could be exchangeable. Thus, translation of SINV mutant lacking the DLP structure (ΔDLP) in 26S mRNA was partially rescued in cells expressing vaccinia virus (VV) E3 protein, a known inhibitor of PKR. This case of heterotypic complementation among evolutionary distant viruses confirmed experimentally a remarkable case of convergent evolution in viral anti-PKR mechanisms. Our data reinforce the critical role of PKR in regulating virus-host interaction and reveal the versatility of viruses to find different solutions to solve the same conflict.
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Affiliation(s)
- Elena Domingo-Gil
- Departamento de Biología Molecular and Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain
| | - René Toribio
- Departamento de Biología Molecular and Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain
| | - José Luis Nájera
- Centro Nacional de Biotecnología (CSIC), Campus Universidad Autónoma de Madrid, Madrid, Spain
| | - Mariano Esteban
- Centro Nacional de Biotecnología (CSIC), Campus Universidad Autónoma de Madrid, Madrid, Spain
| | - Iván Ventoso
- Departamento de Biología Molecular and Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain
- * E-mail:
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Abstract
Zoonotic West Nile virus (WNV) circulates in natural transmission cycles involving certain mosquitoes and birds, horses, humans, and a range of other vertebrates are incidental hosts. Clinical infections in humans can range in severity from uncomplicated WNV fever to fatal meningoencephalitis. Since its introduction to the Western Hemisphere in 1999, WNV had spread across North America, Central and South America and the Caribbean, although the vast majority of severe human cases have occurred in the United States of America (USA) and Canada. By 2002-2003, the WNV outbreaks have involved thousands of patients causing severe neurologic disease (meningoencephalitis and poliomyelitis-like syndrome) and hundreds of associated fatalities in USA. The purpose of this review is to present recent information on the epidemiology and pathogenicity of WNV since its emergence in North America.
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16
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Mansfield KL, Johnson N, Cosby SL, Solomon T, Fooks AR. Transcriptional upregulation of SOCS 1 and suppressors of cytokine signaling 3 mRNA in the absence of suppressors of cytokine signaling 2 mRNA after infection with West Nile virus or tick-borne encephalitis virus. Vector Borne Zoonotic Dis 2011; 10:649-53. [PMID: 20854017 DOI: 10.1089/vbz.2009.0259] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Suppressors of cytokine signaling (SOCS) proteins are a family of proteins that are able to act in a classic negative feedback loop to regulate cytokine signal transduction. The regulation of the immune response by SOCS proteins may contribute to persistent infection or even a fatal outcome. In this study, we have investigated the induction of SOCS 1-3 after peripheral infection with West Nile virus (WNV) or tick-borne encephalitis virus (TBEV) in the murine model. We have shown that the cytokine response after infection of mice with WNV or TBEV induces an upregulation in the brain of mRNA transcripts for SOCS 1 and SOCS 3, but not SOCS 2. We hypothesize that SOCS proteins may play a role in limiting cytokine responses in the brain as a neuroprotective mechanism, which may actually enhance the ability of neuroinvasive viruses such as WNV and TBEV to spread and cause disease.
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Affiliation(s)
- Karen L Mansfield
- Rabies and Wildlife Zoonoses Group, Veterinary Laboratories Agency, New Haw, Addlestone, United Kingdom
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Role of cellular lipids in positive-sense RNA virus replication complex assembly and function. Viruses 2010; 2:1055-1068. [PMID: 21994671 PMCID: PMC3187604 DOI: 10.3390/v2051055] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2010] [Revised: 04/07/2010] [Accepted: 04/22/2010] [Indexed: 01/09/2023] Open
Abstract
Positive-sense RNA viruses are responsible for frequent and often devastating diseases in humans, animals, and plants. However, the development of effective vaccines and anti-viral therapies targeted towards these pathogens has been hindered by an incomplete understanding of the molecular mechanisms involved in viral replication. One common feature of all positive-sense RNA viruses is the manipulation of host intracellular membranes for the assembly of functional viral RNA replication complexes. This review will discuss the interplay between cellular membranes and positive-sense RNA virus replication, and will focus specifically on the potential structural and functional roles for cellular lipids in this process.
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Suthar MS, Ma DY, Thomas S, Lund JM, Zhang N, Daffis S, Rudensky AY, Bevan MJ, Clark EA, Kaja MK, Diamond MS, Gale M. IPS-1 is essential for the control of West Nile virus infection and immunity. PLoS Pathog 2010; 6:e1000757. [PMID: 20140199 PMCID: PMC2816698 DOI: 10.1371/journal.ppat.1000757] [Citation(s) in RCA: 179] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Accepted: 01/07/2010] [Indexed: 02/07/2023] Open
Abstract
The innate immune response is essential for controlling West Nile virus (WNV) infection but how this response is propagated and regulates adaptive immunity in vivo are not defined. Herein, we show that IPS-1, the central adaptor protein to RIG-I-like receptor (RLR) signaling, is essential for triggering of innate immunity and for effective development and regulation of adaptive immunity against pathogenic WNV. IPS-1−/− mice exhibited increased susceptibility to WNV infection marked by enhanced viral replication and dissemination with early viral entry into the CNS. Infection of cultured bone-marrow (BM) derived dendritic cells (DCs), macrophages (Macs), and primary cortical neurons showed that the IPS-1-dependent RLR signaling was essential for triggering IFN defenses and controlling virus replication in these key target cells of infection. Intriguingly, infected IPS-1−/− mice displayed uncontrolled inflammation that included elevated systemic type I IFN, proinflammatory cytokine and chemokine responses, increased numbers of inflammatory DCs, enhanced humoral responses marked by complete loss of virus neutralization activity, and increased numbers of virus-specific CD8+ T cells and non-specific immune cell proliferation in the periphery and in the CNS. This uncontrolled inflammatory response was associated with a lack of regulatory T cell expansion that normally occurs during acute WNV infection. Thus, the enhanced inflammatory response in the absence of IPS-1 was coupled with a failure to protect against WNV infection. Our data define an innate/adaptive immune interface mediated through IPS-1-dependent RLR signaling that regulates the quantity, quality, and balance of the immune response to WNV infection. West Nile virus (WNV) is a mosquito-transmitted RNA virus that has emerged in the Western hemisphere and is now the leading cause of arboviral encephalitis in the United States. However, the virus/host interface that controls WNV pathogenesis is not well understood. Previous studies have established that the innate immune response and interferon (IFN) defenses are essential for controlling virus replication and dissemination. In this study, we assessed the importance of the RIG-I like receptor (RLR) signaling pathway in WNV pathogenesis through analysis of mice lacking IPS-1, the central adaptor molecule of RLR signaling. Our studies revealed that IPS-1 is essential for protection against WNV infection and that it regulates processes that control virus replication and triggering of innate immune defenses. We found that IPS-1 plays an important role in establishing adaptive immunity through an innate/adaptive interface that elicits effective antibody responses and controls the expansion of regulatory T cells. Thus, RLRs are essential for pathogen recognition of WNV infection and their signaling programs help orchestrate immune response maturation, regulation of inflammation, and immune homeostasis that define the outcome of WNV infection.
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Affiliation(s)
- Mehul S. Suthar
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Daphne Y. Ma
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Sunil Thomas
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Jennifer M. Lund
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Nu Zhang
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Stephane Daffis
- Departments of Medicine, Molecular Microbiology, and Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Alexander Y. Rudensky
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Michael J. Bevan
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Edward A. Clark
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Murali-Krishna Kaja
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Michael S. Diamond
- Departments of Medicine, Molecular Microbiology, and Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Michael Gale
- Department of Immunology, University of Washington School of Medicine, Seattle, Washington, United States of America
- Department of Microbiology, University of Washington School of Medicine, Seattle, Washington, United States of America
- * E-mail:
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Mertens E, Kajaste-Rudnitski A, Torres S, Funk A, Frenkiel MP, Iteman I, Khromykh AA, Desprès P. Viral determinants in the NS3 helicase and 2K peptide that promote West Nile virus resistance to antiviral action of 2',5'-oligoadenylate synthetase 1b. Virology 2010; 399:176-185. [PMID: 20100623 DOI: 10.1016/j.virol.2009.12.036] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2009] [Revised: 12/17/2009] [Accepted: 12/31/2009] [Indexed: 11/29/2022]
Abstract
The interferon-inducible 2',5'-oligoadenylate synthetase 1b (Oas1b) protein inhibits West Nile virus (WNV) infection by preventing viral RNA (vRNA) accumulation in infected cells. Serial passage of WNV in Oas1b-expressing mouse cells selected a virus variant with improved growth capacity. Two major amino acid substitutions were identified in this Oas1b-resistant WNV variant: NS3-S365G in the ATPase/helicase domain of NS3 and 2K-V9M in the C-terminal segment of NS4A. To assess their effect on antiviral activity of Oas1b, the NS3 and 2K mutations were engineered into an infectious WNV cDNA clone. The NS3 mutation alters requirement of ATP for ATPase activity and attenuates Oas1b-mediated suppression of vRNA accumulation. However, growth of NS3-mutant virus remains impaired in Oas1b-expressing cells. Only the 2K-V9M mutation efficiently rescued viral growth by promoting vRNA replication. Thus, WNV resistance to Oas1b antiviral action could be attributed to the 2K-V9M substitution with a potential role of NS3-S365G through rescue of vRNA accumulation.
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Affiliation(s)
- Eva Mertens
- Unité Interactions Moléculaires Flavivirus-Hôtes, Institut Pasteur, 75724 Paris, France
| | | | - Shessy Torres
- Centre for Infectious Disease Research, School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | - Anneke Funk
- Centre for Infectious Disease Research, School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | | | - Isabelle Iteman
- Plate-Forme Génotypage des Pathogènes et Santé Publique (PF-8), Institut Pasteur, 75724 Paris, France
| | - Alexander A Khromykh
- Centre for Infectious Disease Research, School of Chemistry and Molecular Biosciences, University of Queensland, St. Lucia, Brisbane, Queensland 4072, Australia
| | - Philippe Desprès
- Unité Interactions Moléculaires Flavivirus-Hôtes, Institut Pasteur, 75724 Paris, France.
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Abstract
A large range of human viruses are associated with the development of arthritis or arthralgia. Although there are many parallels with autoimmune arthritides, there is little evidence that viral arthritides lead to autoimmune disease. In humans viral arthritides usually last from weeks to months, can be debilitating, and are usually treated with non-steroidal anti-inflammatory drugs, but with variable success. Viral arthritides likely arise from immunopathological inflammatory responses directed at viruses and/or their products residing and/or replicating within joint tissues. Macrophages recruited by monocyte chemoattractant protein-1 (MCP-1/CCL2) and activated by interferon, and proinflammatory mediators like tumour necrosis factor alpha, interferon gamma, interleukin-6 and interleukin-1beta appear to be common elements in this group of diseases. The challenge for new treatments is to target excessive inflammation without compromising anti-viral immunity. Recent evidence from mouse models suggests targeting MCP-1 or complement may emerge as viable new treatment options for viral arthritides.
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