51
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Prow NA, Tang B, Gardner J, Le TT, Taylor A, Poo YS, Nakayama E, Hirata TDC, Nakaya HI, Slonchak A, Mukhopadhyay P, Mahalingam S, Schroder WA, Klimstra W, Suhrbier A. Lower temperatures reduce type I interferon activity and promote alphaviral arthritis. PLoS Pathog 2017; 13:e1006788. [PMID: 29281739 PMCID: PMC5770078 DOI: 10.1371/journal.ppat.1006788] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 01/16/2018] [Accepted: 12/04/2017] [Indexed: 12/28/2022] Open
Abstract
Chikungunya virus (CHIKV) belongs to a group of mosquito-borne alphaviruses associated with acute and chronic arthropathy, with peripheral and limb joints most commonly affected. Using a mouse model of CHIKV infection and arthritic disease, we show that CHIKV replication and the ensuing foot arthropathy were dramatically reduced when mice were housed at 30°C, rather than the conventional 22°C. The effect was not associated with a detectable fever, but was dependent on type I interferon responses. Bioinformatics analyses of RNA-Seq data after injection of poly(I:C)/jetPEI suggested the unfolded protein response and certain type I interferon responses are promoted when feet are slightly warmer. The ambient temperature thus appears able profoundly to effect anti-viral activity in the periphery, with clear consequences for alphaviral replication and the ensuing arthropathy. These observations may provide an explanation for why alphaviral arthropathies are largely restricted to joints of the limbs and the extremities.
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Affiliation(s)
- Natalie A. Prow
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- Australian Infectious Disease Research Centre, Brisbane, Queensland, Australia
| | - Bing Tang
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Joy Gardner
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Thuy T. Le
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Adam Taylor
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - Yee S. Poo
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - Eri Nakayama
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Thiago D. C. Hirata
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- School of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Helder I. Nakaya
- School of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo, Brazil
| | - Andrii Slonchak
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland, Australia
| | | | - Suresh Mahalingam
- Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia
| | - Wayne A. Schroder
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - William Klimstra
- Department of Microbiology and Molecular Genetics Center for Vaccine Research University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Andreas Suhrbier
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- Australian Infectious Disease Research Centre, Brisbane, Queensland, Australia
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52
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Highly Pathogenic New World Arenavirus Infection Activates the Pattern Recognition Receptor Protein Kinase R without Attenuating Virus Replication in Human Cells. J Virol 2017; 91:JVI.01090-17. [PMID: 28794024 DOI: 10.1128/jvi.01090-17] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 08/01/2017] [Indexed: 02/07/2023] Open
Abstract
The arenavirus family consists of several highly pathogenic viruses, including the Old World (OW) arenavirus Lassa fever virus (LASV) and the New World (NW) Junin virus (JUNV) and Machupo virus (MACV). Host response to infection by these pathogenic arenaviruses is distinct in many aspects. JUNV and MACV infections readily induce an interferon (IFN) response in human cells, while LASV infection usually triggers an undetectable or weak IFN response. JUNV induces an IFN response through RIG-I, suggesting that the host non-self RNA sensor readily detects JUNV viral RNAs (vRNAs) during infection and activates IFN response. Double-stranded-RNA (dsRNA)-activated protein kinase R (PKR) is another host non-self RNA sensor classically known for its vRNA recognition activity. Here we report that infection with NW arenaviruses JUNV and MACV, but not OW LASV, activated PKR, concomitant with elevated phosphorylation of the translation initiation factor α subunit of eukaryotic initiation factor 2 (eIF2α). Host protein synthesis was substantially suppressed in MACV- and JUNV-infected cells but was only marginally reduced in LASV-infected cells. Despite the antiviral activity known for PKR against many other viruses, the replication of JUNV and MACV was not impaired but was slightly augmented in wild-type (wt) cells compared to that in PKR-deficient cells, suggesting that PKR or PKR activation did not negatively affect JUNV and MACV infection. Additionally, we found an enhanced IFN response in JUNV- or MACV-infected PKR-deficient cells, which was inversely correlated with virus replication.IMPORTANCE The detection of viral RNA by host non-self RNA sensors, including RIG-I and MDA5, is critical to the initiation of the innate immune response to RNA virus infection. Among pathogenic arenaviruses, the OW LASV usually does not elicit an interferon response. However, the NW arenaviruses JUNV and MACV readily trigger an IFN response in a RIG-I-dependent manner. Here, we demonstrate for the first time that pathogenic NW arenaviruses JUNV and MACV, but not the OW arenavirus LASV, activated the dsRNA-dependent PKR, another host non-self RNA sensor, during infection. Interestingly, the replication of JUNV and MACV was not restricted but was rather slightly augmented in the presence of PKR. Our data provide new evidence for a distinct interplay between host non-self RNA sensors and pathogenic arenaviruses, which also provides insights into the pathogenesis of arenaviruses and may facilitate the design of vaccines and treatments against arenavirus-caused diseases.
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53
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Fox JM, Diamond MS. Immune-Mediated Protection and Pathogenesis of Chikungunya Virus. THE JOURNAL OF IMMUNOLOGY 2017; 197:4210-4218. [PMID: 27864552 DOI: 10.4049/jimmunol.1601426] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 09/13/2016] [Indexed: 01/16/2023]
Abstract
Chikungunya virus (CHIKV) is a re-emerging alphavirus that causes debilitating acute and chronic arthritis. Infection by CHIKV induces a robust immune response that is characterized by production of type I IFNs, recruitment of innate and adaptive immune cells, and development of neutralizing Abs. Despite this response, chronic arthritis can develop in some individuals, which may be due to a failure to eliminate viral RNA and Ag and/or persistent immune responses that cause chronic joint inflammation. In this review, based primarily on advances from recent studies in mice, we discuss the innate and adaptive immune factors that control CHIKV dissemination and clearance or contribute to pathogenesis.
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Affiliation(s)
- Julie M Fox
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Michael S Diamond
- Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110; .,Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110.,Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63110; and.,Center for Human Immunology and Immunotherapy Programs, Washington University School of Medicine, St. Louis, MO 63110
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54
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Vanacker H, Vetters J, Moudombi L, Caux C, Janssens S, Michallet MC. Emerging Role of the Unfolded Protein Response in Tumor Immunosurveillance. Trends Cancer 2017; 3:491-505. [PMID: 28718404 DOI: 10.1016/j.trecan.2017.05.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 05/15/2017] [Accepted: 05/19/2017] [Indexed: 02/07/2023]
Abstract
Disruption of endoplasmic reticulum (ER) homeostasis results in ER stress and activation of the unfolded protein response (UPR). This response alleviates cell stress, and is activated in both tumor cells and tumor infiltrating immune cells. The UPR plays a dual function in cancer biology, acting as a barrier to tumorigenesis at the premalignant stage, while fostering cancer maintenance in established tumors. In infiltrating immune cells, the UPR has been involved in both immunosurveillance and immunosuppressive functions. This review aims to decipher the role of the UPR at different stages of tumorigenesis and how the UPR shapes the balance between immunosurveillance and immune escape. This knowledge may improve existing UPR-targeted therapies and the design of novel strategies for cancer treatment.
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Affiliation(s)
- Hélène Vanacker
- Univ Lyon, Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286, Centre Léon Bérard, Centre de recherche en cancérologie de Lyon, Lyon, 69008, France
| | - Jessica Vetters
- Laboratory of Immunoregulation and Mucosal Immunology, VIB Center for Inflammation Research, Ghent, Belgium and Department of Internal Medicine, Ghent University, Ghent, Belgium
| | - Lyvia Moudombi
- Univ Lyon, Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286, Centre Léon Bérard, Centre de recherche en cancérologie de Lyon, Lyon, 69008, France
| | - Christophe Caux
- Univ Lyon, Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286, Centre Léon Bérard, Centre de recherche en cancérologie de Lyon, Lyon, 69008, France
| | - Sophie Janssens
- Laboratory of Immunoregulation and Mucosal Immunology, VIB Center for Inflammation Research, Ghent, Belgium and Department of Internal Medicine, Ghent University, Ghent, Belgium
| | - Marie-Cécile Michallet
- Univ Lyon, Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286, Centre Léon Bérard, Centre de recherche en cancérologie de Lyon, Lyon, 69008, France.
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55
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Abstract
Efficient viral gene expression is threatened by cellular stress response programmes that rapidly reprioritize the translation machinery in response to varied environmental assaults, including virus infection. This results in inhibition of bulk synthesis of housekeeping proteins and causes the aggregation of messenger ribonucleoprotein complexes into cytoplasmic foci that are known as stress granules, which can entrap viral mRNAs. There is accumulating evidence for the antiviral nature of stress granules, which is supported by the discovery of many viral factors that interfere with stress granule formation and/or function. This Review focuses on recent advances in our understanding of the role of translation inhibition and stress granules in antiviral immune responses.
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56
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Perego J, Bourbon C, Chasson L, Laprie C, Spinelli L, Camosseto V, Gatti E, Pierre P. Guanabenz Prevents d-Galactosamine/Lipopolysaccharide-Induced Liver Damage and Mortality. Front Immunol 2017; 8:679. [PMID: 28659918 PMCID: PMC5468566 DOI: 10.3389/fimmu.2017.00679] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 05/24/2017] [Indexed: 12/19/2022] Open
Abstract
Multi-organ failure in response to uncontrolled microbial infection is characterized by low blood pressure accompanied by a systemic over-inflammation state, caused by massive pro-inflammatory cytokines release and liver damage. Recently, the integrated stress response (ISR), characterized by eukaryotic translation initiation factor 2α (eIF2α) phosphorylation, was involved with controlling apoptosis in stressed hepatocytes and associated with poor survival to endotoxin challenge. Lipopolysaccharide (LPS) alone is able to induce the ISR in hepatocytes and can trigger massive liver damage along with tumor necrosis factor-alpha (TNF-α) expression. Consequently, drugs interfering with eIF2α phosphorylation may represent potential candidates for the treatment of such pathologies. We, therefore, used Guanabenz (GBZ), a small compound with enhancing eIF2α phosphorylation activity to evaluate its effect on bacterial LPS sensing and endotoxemia. GBZ is confirmed here to have an anti-inflammatory activity by increasing in vitro interleukin-10 (IL-10) production by LPS-stimulated dendritic cells. We further show that in the d-galactosamine (d-galN)/LPS-dependent lethality model, intraperitoneal injection of GBZ promoted mice survival, prevented liver damage, increased IL-10 levels, and inhibited TNF-α production. GBZ and its derivatives could therefore represent an interesting pharmacological solution to control systemic inflammation and associated acute liver failure.
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Affiliation(s)
- Jessica Perego
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France
| | | | - Lionel Chasson
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France
| | - Caroline Laprie
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France
| | - Lionel Spinelli
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France
| | | | - Evelina Gatti
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France.,Aveiro Health Sciences Program, Institute for Research in Biomedicine (iBiMED), University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA), CNRS "Mistra", Marseille, France
| | - Philippe Pierre
- CIML, Aix-Marseille University, CNRS, INSERM, Marseille, France.,Aveiro Health Sciences Program, Institute for Research in Biomedicine (iBiMED), University of Aveiro, Aveiro, Portugal.,International Associated Laboratory (LIA), CNRS "Mistra", Marseille, France
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57
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Regulated IRE1-dependent mRNA decay sets the threshold for dendritic cell survival. Nat Cell Biol 2017; 19:698-710. [PMID: 28459443 DOI: 10.1038/ncb3518] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 03/21/2017] [Indexed: 12/23/2022]
Abstract
The IRE1-XBP1 signalling pathway is part of a cellular programme that protects against endoplasmic reticulum (ER) stress, but also controls development and survival of immune cells. Loss of XBP1 in splenic type 1 conventional dendritic cells (cDC1s) results in functional alterations without affecting cell survival. However, in mucosal cDC1s, loss of XBP1 impaired survival in a tissue-specific manner-while lung cDC1s die, intestinal cDC1s survive. This was not caused by differential activation of ER stress cell-death regulators CHOP or JNK. Rather, survival of intestinal cDC1s was associated with their ability to shut down protein synthesis through a protective integrated stress response and their marked increase in regulated IRE1-dependent messenger RNA decay. Furthermore, loss of IRE1 endonuclease on top of XBP1 led to cDC1 loss in the intestine. Thus, mucosal DCs differentially mount ATF4- and IRE1-dependent adaptive mechanisms to survive in the face of ER stress.
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58
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Perera N, Miller JL, Zitzmann N. The role of the unfolded protein response in dengue virus pathogenesis. Cell Microbiol 2017; 19. [PMID: 28207988 DOI: 10.1111/cmi.12734] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2017] [Revised: 02/12/2017] [Accepted: 02/14/2017] [Indexed: 12/31/2022]
Abstract
Symptomatic dengue virus (DENV) infections range from mild fever to severe haemorrhagic disease and death. Host-viral interactions play a significant role in deciding the fate of the infection. The unfolded protein response (UPR) is a prosurvival cellular reaction induced in response to DENV-mediated endoplasmic reticulum stress. The UPR has complex interactions with the cellular autophagy machinery, apoptosis, and innate immunity. DENV has evolved to manipulate the UPR to facilitate its replication and to evade host immunity. Our knowledge of this intertwined network of events is continuously developing. A better understanding of the UPR mediated antiviral and proviral effects will shed light on dengue disease pathogenesis and may help development of anti-DENV therapeutics. This review summarizes the role of the UPR in viral replication, autophagy, and DENV-induced inflammation to describe how a host response contributes to DENV pathogenesis.
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Affiliation(s)
- Nilanka Perera
- Antiviral Research Unit, Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford, UK.,Department of Medicine, Faculty of Medical Sciences, University of Sri Jayewardenepura, Nugegoda, Sri Lanka
| | - Joanna L Miller
- Antiviral Research Unit, Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford, UK
| | - Nicole Zitzmann
- Antiviral Research Unit, Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, Oxford, UK
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59
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Zarcone MC, van Schadewijk A, Duistermaat E, Hiemstra PS, Kooter IM. Diesel exhaust alters the response of cultured primary bronchial epithelial cells from patients with chronic obstructive pulmonary disease (COPD) to non-typeable Haemophilus influenzae. Respir Res 2017; 18:27. [PMID: 28129777 PMCID: PMC5273858 DOI: 10.1186/s12931-017-0510-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 01/16/2017] [Indexed: 01/02/2023] Open
Abstract
BACKGROUND Exacerbations constitute a major cause of morbidity and mortality in patients suffering from chronic obstructive pulmonary disease (COPD). Both bacterial infections, such as those with non-typeable Haemophilus influenzae (NTHi), and exposures to diesel engine emissions are known to contribute to exacerbations in COPD patients. However, the effect of diesel exhaust (DE) exposure on the epithelial response to microbial stimulation is incompletely understood, and possible differences in the response to DE of epithelial cells from COPD patients and controls have not been studied. METHODS Primary bronchial epithelial cells (PBEC) were obtained from age-matched COPD patients (n = 7) and controls (n = 5). PBEC were cultured at the air-liquid interface (ALI) to achieve mucociliary differentiation. ALI-PBECs were apically exposed for 1 h to a stream of freshly generated whole DE or air. Exposure was followed by 3 h incubation in presence or absence of UV-inactivated NTHi before analysis of epithelial gene expression. RESULTS DE alone induced an increase in markers of oxidative stress (HMOX1, 50-100-fold) and of the integrated stress response (CHOP, 1.5-2-fold and GADD34, 1.5-fold) in cells from both COPD patients and controls. Exposure of COPD cultures to DE followed by NTHi caused an additive increase in GADD34 expression (up to 3-fold). Importantly, DE caused an inhibition of the NTHi-induced expression of the antimicrobial peptide S100A7, and of the chaperone protein HSP5A/BiP. CONCLUSIONS Our findings show that DE exposure of differentiated primary airway epithelial cells causes activation of the gene expression of HMOX1 and markers of integrated stress response to a similar extent in cells from COPD donors and controls. Furthermore, DE further increased the NTHi-induced expression of GADD34, indicating a possible enhancement of the integrated stress response. DE reduced the NTHi-induced expression of S100A7. These data suggest that DE exposure may cause adverse health effects in part by decreasing host defense against infection and by modulating stress responses.
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Affiliation(s)
- Maria C Zarcone
- Department of Pulmonology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands.
| | - Annemarie van Schadewijk
- Department of Pulmonology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | | | - Pieter S Hiemstra
- Department of Pulmonology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands
| | - Ingeborg M Kooter
- Netherlands Organization for Applied Scientific Research, Utrecht, The Netherlands
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60
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Dalet A, Argüello RJ, Combes A, Spinelli L, Jaeger S, Fallet M, Vu Manh TP, Mendes A, Perego J, Reverendo M, Camosseto V, Dalod M, Weil T, Santos MA, Gatti E, Pierre P. Protein synthesis inhibition and GADD34 control IFN-β heterogeneous expression in response to dsRNA. EMBO J 2017; 36:761-782. [PMID: 28100675 DOI: 10.15252/embj.201695000] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 12/20/2016] [Accepted: 12/22/2016] [Indexed: 02/01/2023] Open
Abstract
In innate immune responses, induction of type-I interferons (IFNs) prevents virus spreading while viral replication is delayed by protein synthesis inhibition. We asked how cells perform these apparently contradictory activities. Using single fibroblast monitoring by flow cytometry and mathematical modeling, we demonstrate that type-I IFN production is linked to cell's ability to enter dsRNA-activated PKR-dependent translational arrest and then overcome this inhibition by decreasing eIF2α phosphorylation through phosphatase 1c cofactor GADD34 (Ppp1r15a) expression. GADD34 expression, shown here to be dependent on the IRF3 transcription factor, is responsible for a biochemical cycle permitting pulse of IFN synthesis to occur in cells undergoing protein synthesis inhibition. Translation arrest is further demonstrated to be key for anti-viral response by acting synergistically with MAVS activation to amplify TBK1 signaling and IFN-β mRNA transcription, while GADD34-dependent protein synthesis recovery contributes to the heterogeneous expression of IFN observed in dsRNA-activated cells.
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Affiliation(s)
- Alexandre Dalet
- CNRS, INSERM, CIML, Aix Marseille University, Marseille, France
| | | | - Alexis Combes
- CNRS, INSERM, CIML, Aix Marseille University, Marseille, France
| | - Lionel Spinelli
- CNRS, INSERM, CIML, Aix Marseille University, Marseille, France
| | | | - Mathieu Fallet
- CNRS, INSERM, CIML, Aix Marseille University, Marseille, France
| | | | - Andreia Mendes
- CNRS, INSERM, CIML, Aix Marseille University, Marseille, France
| | - Jessica Perego
- CNRS, INSERM, CIML, Aix Marseille University, Marseille, France
| | | | - Voahirana Camosseto
- CNRS, INSERM, CIML, Aix Marseille University, Marseille, France.,International associated laboratory (LIA) CNRS "Mistra", Marseille, France
| | - Marc Dalod
- CNRS, INSERM, CIML, Aix Marseille University, Marseille, France
| | - Tobias Weil
- Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, Aveiro, Portugal
| | - Manuel A Santos
- International associated laboratory (LIA) CNRS "Mistra", Marseille, France.,Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, Aveiro, Portugal
| | - Evelina Gatti
- CNRS, INSERM, CIML, Aix Marseille University, Marseille, France .,International associated laboratory (LIA) CNRS "Mistra", Marseille, France.,Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, Aveiro, Portugal
| | - Philippe Pierre
- CNRS, INSERM, CIML, Aix Marseille University, Marseille, France .,International associated laboratory (LIA) CNRS "Mistra", Marseille, France.,Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, Aveiro, Portugal
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61
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The Unfolded Protein Response in the Immune Cell Development: Putting the Caretaker in the Driving Seat. Curr Top Microbiol Immunol 2017; 414:45-72. [PMID: 28702709 DOI: 10.1007/82_2017_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The endoplasmic reticulum (ER) is the primary site for the folding of proteins destined for the membranous compartment and the extracellular space. This elaborate function is coordinated by the unfolded protein response (UPR), a stress-activated cellular program that governs proteostasis. In multicellular organisms, cells have adopted specialized functions, which required functional adaptations of the ER and its UPR. Recently, it has become clear that in immune cells, the UPR has acquired functions that stretch far beyond its original scope. In this review, we will discuss the role of the UPR in the immune system and highlight the plasticity of this signaling cascade throughout immune cell development .
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62
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Herzner AM, Wolter S, Zillinger T, Schmitz S, Barchet W, Hartmann G, Bartok E, Schlee M. G-rich DNA-induced stress response blocks type-I-IFN but not CXCL10 secretion in monocytes. Sci Rep 2016; 6:38405. [PMID: 27941826 PMCID: PMC5150577 DOI: 10.1038/srep38405] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Accepted: 11/03/2016] [Indexed: 12/17/2022] Open
Abstract
Excessive inflammation can cause damage to host cells and tissues. Thus, the secretion of inflammatory cytokines is tightly regulated at transcriptional, post-transcriptional and post-translational levels and influenced by cellular stress responses, such as endoplasmic reticulum (ER) stress or apoptosis. Here, we describe a novel type of post-transcriptional regulation of the type-I-IFN response that was induced in monocytes by cytosolic transfection of a short immunomodulatory DNA (imDNA), a G-tetrad forming CpG-free derivative of the TLR9 agonist ODN2216. When co-transfected with cytosolic nucleic acid stimuli (DNA or 3P-dsRNA), imDNA induced caspase-3 activation, translational shutdown and upregulation of stress-induced genes. This stress response inhibited the type-I-IFN induction at the translational level. By contrast, the induction of most type-I-IFN-associated chemokines, including Chemokine (C-X-C Motif) Ligand (CXCL)10 was not affected, suggesting a differential translational regulation of chemokines and type-I-IFN. Pan-caspase inhibitors could restore IFN-β secretion, yet, strikingly, caspase inhibition did not restore global translation but instead induced a compensatory increase in the transcription of IFN-β but not CXCL10. Altogether, our data provide evidence for a differential regulation of cytokine release at both transcriptional and post-transcriptional levels which suppresses type-I-IFN induction yet allows for CXCL10 secretion during imDNA-induced cellular stress.
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Affiliation(s)
- Anna-Maria Herzner
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Steven Wolter
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Thomas Zillinger
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany.,German Center for Infection Research (DZIF), Cologne-Bonn, Germany
| | - Saskia Schmitz
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Winfried Barchet
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany.,German Center for Infection Research (DZIF), Cologne-Bonn, Germany
| | - Gunther Hartmann
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Eva Bartok
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
| | - Martin Schlee
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, Bonn, Germany
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63
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Moretti J, Blander JM. Cell-autonomous stress responses in innate immunity. J Leukoc Biol 2016; 101:77-86. [PMID: 27733577 DOI: 10.1189/jlb.2mr0416-201r] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Revised: 08/10/2016] [Accepted: 08/24/2016] [Indexed: 12/12/2022] Open
Abstract
The innate immune response of phagocytes to microbes has long been known to depend on the core signaling cascades downstream of pattern recognition receptors (PRRs), which lead to expression and production of inflammatory cytokines that counteract infection and induce adaptive immunity. Cell-autonomous responses have recently emerged as important mechanisms of innate immunity. Either IFN-inducible or constitutive, these processes aim to guarantee cell homeostasis but have also been shown to modulate innate immune response to microbes and production of inflammatory cytokines. Among these constitutive cell-autonomous responses, autophagy is prominent and its role in innate immunity has been well characterized. Other stress responses, such as metabolic stress, the ER stress/unfolded protein response, mitochondrial stress, or the DNA damage response, seem to also be involved in innate immunity, although the precise mechanisms by which they regulate the innate immune response are not yet defined. Of importance, these distinct constitutive cell-autonomous responses appear to be interconnected and can also be modulated by microbes and PRRs, which add further complexity to the interplay between innate immune signaling and cell-autonomous responses in the mediation of an efficient innate immune response.
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Affiliation(s)
- Julien Moretti
- Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - J Magarian Blander
- Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA; .,Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,The Tisch Cancer Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA.,Graduate School of Biological Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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64
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Su Hui Teo C, Serwa RA, O’Hare P. Spatial and Temporal Resolution of Global Protein Synthesis during HSV Infection Using Bioorthogonal Precursors and Click Chemistry. PLoS Pathog 2016; 12:e1005927. [PMID: 27706239 PMCID: PMC5051704 DOI: 10.1371/journal.ppat.1005927] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Accepted: 09/12/2016] [Indexed: 12/04/2022] Open
Abstract
We used pulse-labeling with the methionine analogue homopropargylglycine (HPG) to investigate spatiotemporal aspects of protein synthesis during herpes simplex virus (HSV) infection. In vivo incorporation of HPG enables subsequent selective coupling of fluorochrome-capture reagents to newly synthesised proteins. We demonstrate that HPG labeling had no effect on cell viability, on accumulation of test early or late viral proteins, or on overall virus yields. HPG pulse-labeling followed by SDS-PAGE analysis confirmed incorporation into newly synthesised proteins, while parallel processing by in situ cycloaddition revealed new insight into spatiotemporal aspects of protein localisation during infection. A striking feature was the rapid accumulation of newly synthesised proteins not only in a general nuclear pattern but additionally in newly forming sub-compartments represented by small discrete foci. These newly synthesised protein domains (NPDs) were similar in size and morphology to PML domains but were more numerous, and whereas PML domains were progressively disrupted, NPDs were progressively induced and persisted. Immediate-early proteins ICP4 and ICP0 were excluded from NPDs, but using an ICP0 mutant defective in PML disruption, we show a clear spatial relationship between NPDs and PML domains with NPDs frequently forming immediately adjacent and co-joining persisting PML domains. Further analysis of location of the chaperone Hsc70 demonstrated that while NPDs formed early in infection without overt Hsc70 recruitment, later in infection Hsc70 showed pronounced recruitment frequently in a coat-like fashion around NPDs. Moreover, while ICP4 and ICP0 were excluded from NPDs, ICP22 showed selective recruitment. Our data indicate that NPDs represent early recruitment of host and viral de novo translated protein to distinct structural entities which are precursors to the previously described VICE domains involved in protein quality control in the nucleus, and reveal new features from which we propose spatially linked platforms of newly synthesised protein processing after nuclear import.
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Affiliation(s)
- Catherine Su Hui Teo
- Section of Virology, Faculty of Medicine, Imperial College London, St Mary’s Medical School, Norfolk Place, London, United Kingdom
| | - Remigiusz A. Serwa
- Department of Chemistry, Imperial College London, London, United Kingdom
| | - Peter O’Hare
- Section of Virology, Faculty of Medicine, Imperial College London, St Mary’s Medical School, Norfolk Place, London, United Kingdom
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65
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Abstract
In multicellular organisms, the epithelia is a contact surface with the surrounding environment and is exposed to a variety of adverse biotic (pathogenic) and abiotic (chemical) factors. Multi-layered pathways that operate on different time scales have evolved to preserve cellular integrity and elicit stress-specific response. Several stress-response programs are activated until a complete elimination of the stress is achieved. The innate immune response, which is triggered by pathogenic invasion, is rather harmful when active over a prolonged time, thus the response follows characteristic oscillatory trajectories. Here, we review different translation programs that function to precisely fine-tune the time at which various components of the innate immune response dwell between active and inactive. We discuss how different pro-inflammatory pathways are co-ordinated to temporally offset single reactions and to achieve an optimal balance between fighting pathogens and being less harmful for healthy cells.
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66
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Jan E, Mohr I, Walsh D. A Cap-to-Tail Guide to mRNA Translation Strategies in Virus-Infected Cells. Annu Rev Virol 2016; 3:283-307. [PMID: 27501262 DOI: 10.1146/annurev-virology-100114-055014] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although viruses require cellular functions to replicate, their absolute dependence upon the host translation machinery to produce polypeptides indispensable for their reproduction is most conspicuous. Despite their incredible diversity, the mRNAs produced by all viruses must engage cellular ribosomes. This has proven to be anything but a passive process and has revealed a remarkable array of tactics for rapidly subverting control over and dominating cellular regulatory pathways that influence translation initiation, elongation, and termination. Besides enforcing viral mRNA translation, these processes profoundly impact host cell-intrinsic immune defenses at the ready to deny foreign mRNA access to ribosomes and block protein synthesis. Finally, genome size constraints have driven the evolution of resourceful strategies for maximizing viral coding capacity. Here, we review the amazing strategies that work to regulate translation in virus-infected cells, highlighting both virus-specific tactics and the tremendous insight they provide into fundamental translational control mechanisms in health and disease.
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Affiliation(s)
- Eric Jan
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada;
| | - Ian Mohr
- Department of Microbiology and New York University Cancer Institute, New York University School of Medicine, New York, NY 10016;
| | - Derek Walsh
- Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611;
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67
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A novel infection- and inflammation-associated molecular signature in peripheral blood of myasthenia gravis patients. Immunobiology 2016; 221:1227-36. [PMID: 27387891 DOI: 10.1016/j.imbio.2016.06.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 06/13/2016] [Indexed: 12/15/2022]
Abstract
Myasthenia gravis (MG) is a T-cell dependent autoimmune disorder of the neuromuscular junction, characterised by muscle weakness and fatigability. Autoimmunity is thought to initiate in the thymus of acetylcholine receptor (AChR)-positive MG patients; however, the molecular mechanisms linking intra-thymic MG pathogenesis with autoreactivity via the circulation to the muscle target organ are poorly understood. Using whole-transcriptome sequencing, we compared the transcriptional profile of peripheral blood mononuclear cells from AChR-early onset MG (AChR-EOMG) patients with healthy controls: 178 coding transcripts and 229 long non-coding RNAs, including 11 pre-miRNAs, were differentially expressed. Among the 178 coding transcripts, 128 were annotated of which 17% were associated with the 'infectious disease' functional category and 46% with 'inflammatory disease' and 'inflammatory response-associated' categories. Validation of selected transcripts by qPCR indicated that of the infectious disease-related transcripts, ETF1, NFKB2, PLK3, and PPP1R15A were upregulated, whereas CLC and IL4 were downregulated in AChR-EOMG patients; in the 'inflammatory' categories, ABCA1, FUS, and RELB were upregulated, suggesting a contribution of these molecules to immunological dysfunctions in MG. Data selection and validation were also based on predicted microRNA-mRNA interactions. We found that miR-612, miR-3654, and miR-3651 were increased, whereas miR-612-putative AKAp12 and HRH4 targets and the miR-3651-putative CRISP3 target were downregulated in AChR-EOMG, also suggesting altered immunoregulation. Our findings reveal a novel peripheral molecular signature in AChR-EOMG, reflecting a critical involvement of inflammatory- and infectious disease-related immune responses in disease pathogenesis.
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68
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GADD34 suppresses lipopolysaccharide-induced sepsis and tissue injury through the regulation of macrophage activation. Cell Death Dis 2016; 7:e2219. [PMID: 27171261 PMCID: PMC4917654 DOI: 10.1038/cddis.2016.116] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 03/31/2016] [Accepted: 04/07/2016] [Indexed: 01/22/2023]
Abstract
Growth arrest and DNA damage inducible protein 34 (GADD34) is induced by various cellular stresses, such as DNA damage, endoplasmic reticulum stress, and amino-acid deprivation. Although the major roles of GADD34 are regulating ER stress responses and apoptosis, a recent study suggested that GADD34 is linked to innate immune responses. In this report, we investigated the roles of GADD34 in inflammatory responses against bacterial infection. To explore the effects of GADD34 on systemic inflammation in vivo, we employed a lipopolysaccharide (LPS)-induced murine sepsis model and assessed the lethality, serum cytokine levels, and tissue injury in the presence or absence of GADD34. We found that GADD34 deficiency increased the lethality and serum cytokine levels in LPS-induced sepsis. Moreover, GADD34 deficiency enhanced tissue destruction, cell death, and pro-inflammatory cytokine expression in LPS-induced acute liver injury. Pro-inflammatory cytokine production after LPS stimulation is regulated by the Toll-like receptor 4 (TLR4)-mediated NF-κB signaling pathway. In vitro experiments revealed that GADD34 suppressed pro-inflammatory cytokine production by macrophages through dephosphorylation of IKKβ. In conclusion, GADD34 attenuates LPS-induced sepsis and acute tissue injury through suppressing macrophage activation. Targeting this anti-inflammatory role of GADD34 may be a promising area for the development of therapeutic agents to regulate inflammatory disorders.
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69
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Martins AS, Alves I, Helguero L, Domingues MR, Neves BM. The Unfolded Protein Response in Homeostasis and Modulation of Mammalian Immune Cells. Int Rev Immunol 2016; 35:457-476. [PMID: 27119724 DOI: 10.3109/08830185.2015.1110151] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The endoplasmic reticulum (ER) plays important roles in eukaryotic protein folding and lipid biosynthesis. Several exogenous and endogenous cellular sources of stress can perturb ER homeostasis leading to the accumulation of unfolded proteins in the lumen. Unfolded protein accumulation triggers a signal-transduction cascade known as the unfolded protein response (UPR), an adaptive mechanism which aims to protect cells from protein aggregates and to restore ER functions. Further to this protective mechanism, in immune cells, UPR molecular effectors have been shown to participate in a wide range of biological processes such as cell differentiation, survival and immunoglobulin and cytokine production. Recent findings also highlight the involvement of the UPR machinery in the maturational program and antigen presentation capacities of dendritic cells. UPR is therefore a key element in immune system homeostasis with direct implications on both adaptive and innate immune responses. The present review summarizes the knowledge on the emerging roles of UPR signaling cascades in mammalian immune cells as well as the consequences of their dysregulation in relation to the pathogenesis of several diseases.
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Affiliation(s)
- Ana Sofia Martins
- a Mass Spectrometry Centre, Department of Chemistry and QOPNA , University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal
| | - Inês Alves
- a Mass Spectrometry Centre, Department of Chemistry and QOPNA , University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal
| | - Luisa Helguero
- a Mass Spectrometry Centre, Department of Chemistry and QOPNA , University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal.,b Institute for Research in Biomedicine - iBiMED, Health Sciences Program, Universidade de Aveiro , Portugal
| | - Maria Rosário Domingues
- a Mass Spectrometry Centre, Department of Chemistry and QOPNA , University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal
| | - Bruno Miguel Neves
- a Mass Spectrometry Centre, Department of Chemistry and QOPNA , University of Aveiro, Campus Universitário de Santiago , Aveiro , Portugal.,c Faculty of Pharmacy and Centre for Neuroscience and Cell Biology, University of Coimbra , Coimbra , Portugal
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70
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Clavarino G, Adriouach S, Quesada JL, Clay M, Chevreau M, Trocmé C, Grange L, Gaudin P, Gatti E, Pierre P, Cesbron JY, Dumestre-Pérard C. Unfolded protein response gene GADD34 is overexpressed in rheumatoid arthritis and related to the presence of circulating anti-citrullinated protein antibodies. Autoimmunity 2016; 49:172-8. [DOI: 10.3109/08916934.2016.1138220] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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71
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Activation of the DNA Damage Response by RNA Viruses. Biomolecules 2016; 6:2. [PMID: 26751489 PMCID: PMC4808796 DOI: 10.3390/biom6010002] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 11/17/2015] [Accepted: 11/24/2015] [Indexed: 12/11/2022] Open
Abstract
RNA viruses are a genetically diverse group of pathogens that are responsible for some of the most prevalent and lethal human diseases. Numerous viruses introduce DNA damage and genetic instability in host cells during their lifecycles and some species also manipulate components of the DNA damage response (DDR), a complex and sophisticated series of cellular pathways that have evolved to detect and repair DNA lesions. Activation and manipulation of the DDR by DNA viruses has been extensively studied. It is apparent, however, that many RNA viruses can also induce significant DNA damage, even in cases where viral replication takes place exclusively in the cytoplasm. DNA damage can contribute to the pathogenesis of RNA viruses through the triggering of apoptosis, stimulation of inflammatory immune responses and the introduction of deleterious mutations that can increase the risk of tumorigenesis. In addition, activation of DDR pathways can contribute positively to replication of viral RNA genomes. Elucidation of the interactions between RNA viruses and the DDR has provided important insights into modulation of host cell functions by these pathogens. This review summarises the current literature regarding activation and manipulation of the DDR by several medically important RNA viruses.
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72
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Kavaliauskis A, Arnemo M, Rishovd AL, Gjøen T. Activation of unfolded protein response pathway during infectious salmon anemia virus (ISAV) infection in vitro an in vivo. DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2016; 54:46-54. [PMID: 26303456 DOI: 10.1016/j.dci.2015.08.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Revised: 08/17/2015] [Accepted: 08/17/2015] [Indexed: 06/04/2023]
Abstract
Infectious salmon anemia virus (ISAV) is a salmon pathogen causing serious outbreaks in fish farms world-wide. There is currently no effective commercially available vaccine and there is a need for better understanding of host pathogen interactions with this virus. Various strains can cause both acute and persistent infections and therefore establish a balance with the host immune responses. We have studied host responses to this infection by analyzing the main branches of the unfolded protein response (UPR) in salmon cells in vitro and in tissues from infected fish to gain a better understanding of virus-host interactions. ISAV induce the main symptoms and signaling pathways of UPR (ATF6, PERK and IRE1) without inducing translational attenuation. This may be due to concomitant induction of an important negative feedback loop via the phosphatase regulator GADD34. The host cells can therefore respond with translation of cytokine and antiviral proteins to curb or control infection.
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Affiliation(s)
- Arturas Kavaliauskis
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, PO Box 1068 Blindern, NO-0316 Oslo, Norway.
| | - Marianne Arnemo
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, PO Box 1068 Blindern, NO-0316 Oslo, Norway.
| | - Anne-Lise Rishovd
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, PO Box 1068 Blindern, NO-0316 Oslo, Norway.
| | - Tor Gjøen
- Department of Pharmaceutical Biosciences, School of Pharmacy, University of Oslo, PO Box 1068 Blindern, NO-0316 Oslo, Norway.
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73
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Kibenge F, Kibenge M. Orthomyxoviruses of Fish. AQUACULTURE VIROLOGY 2016. [PMCID: PMC7173593 DOI: 10.1016/b978-0-12-801573-5.00019-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The family Orthomyxoviridae is well known for containing influenza viruses with a segmented RNA genome that is prone to gene reassortment in mixed infections (known as antigenic shift) resulting in new virus subtypes that cause pandemics, and cumulative mutations (known as antigenic drift), resulting in new virus strains that cause epidemics. This family also contains infectious salmon anemia virus (ISAV) and tilapia lake virus (TiLV), which are a unique orthomyxoviruses that infect fish and is unable to replicate above room temperature (24°C). This chapter describes the comparative virology of members in the family Orthomyxoviridae in general, helping to understand the emergent teleost orthomyxoviruses, ISAV and TiLV. The most current information on virus–host interactions of the fish orthomyxoviruses, particularly ISAV, as they relate to variations in virus structure, virulence, persistence, host range and immunological aspects is presented in detail.
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74
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γδ T Cells Play a Protective Role in Chikungunya Virus-Induced Disease. J Virol 2015; 90:433-43. [PMID: 26491151 DOI: 10.1128/jvi.02159-15] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 10/12/2015] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Chikungunya virus (CHIKV) is an alphavirus responsible for causing epidemic outbreaks of polyarthralgia in humans. Because CHIKV is initially introduced via the skin, where γδ T cells are prevalent, we evaluated the response of these cells to CHIKV infection. CHIKV infection led to a significant increase in γδ T cells in the infected foot and draining lymph node that was associated with the production of proinflammatory cytokines and chemokines in C57BL/6J mice. γδ T cell(-/-) mice demonstrated exacerbated CHIKV disease characterized by less weight gain and greater foot swelling than occurred in wild-type mice, as well as a transient increase in monocytes and altered cytokine/chemokine expression in the foot. Histologically, γδ T cell(-/-) mice had increased inflammation-mediated oxidative damage in the ipsilateral foot and ankle joint compared to wild-type mice which was independent of differences in CHIKV replication. These results suggest that γδ T cells play a protective role in limiting the CHIKV-induced inflammatory response and subsequent tissue and joint damage. IMPORTANCE Recent epidemics, including the 2004 to 2007 outbreak and the spread of CHIKV to naive populations in the Caribbean and Central and South America with resultant cases imported into the United States, have highlighted the capacity of CHIKV to cause explosive epidemics where the virus can spread to millions of people and rapidly move into new areas. These studies identified γδ T cells as important to both recruitment of key inflammatory cell populations and dampening the tissue injury due to oxidative stress. Given the importance of these cells in the early response to CHIKV, this information may inform the development of CHIKV vaccines and therapeutics.
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75
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van der Lee R, Feng Q, Langereis MA, ter Horst R, Szklarczyk R, Netea MG, Andeweg AC, van Kuppeveld FJM, Huynen MA. Integrative Genomics-Based Discovery of Novel Regulators of the Innate Antiviral Response. PLoS Comput Biol 2015; 11:e1004553. [PMID: 26485378 PMCID: PMC4618338 DOI: 10.1371/journal.pcbi.1004553] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2015] [Accepted: 09/12/2015] [Indexed: 01/16/2023] Open
Abstract
The RIG-I-like receptor (RLR) pathway is essential for detecting cytosolic viral RNA to trigger the production of type I interferons (IFNα/β) that initiate an innate antiviral response. Through systematic assessment of a wide variety of genomics data, we discovered 10 molecular signatures of known RLR pathway components that collectively predict novel members. We demonstrate that RLR pathway genes, among others, tend to evolve rapidly, interact with viral proteins, contain a limited set of protein domains, are regulated by specific transcription factors, and form a tightly connected interaction network. Using a Bayesian approach to integrate these signatures, we propose likely novel RLR regulators. RNAi knockdown experiments revealed a high prediction accuracy, identifying 94 genes among 187 candidates tested (~50%) that affected viral RNA-induced production of IFNβ. The discovered antiviral regulators may participate in a wide range of processes that highlight the complexity of antiviral defense (e.g. MAP3K11, CDK11B, PSMA3, TRIM14, HSPA9B, CDC37, NUP98, G3BP1), and include uncharacterized factors (DDX17, C6orf58, C16orf57, PKN2, SNW1). Our validated RLR pathway list (http://rlr.cmbi.umcn.nl/), obtained using a combination of integrative genomics and experiments, is a new resource for innate antiviral immunity research.
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Affiliation(s)
- Robin van der Lee
- Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Qian Feng
- Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, University of Utrecht, Utrecht, The Netherlands
| | - Martijn A. Langereis
- Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, University of Utrecht, Utrecht, The Netherlands
| | - Rob ter Horst
- Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Radek Szklarczyk
- Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Mihai G. Netea
- Department of Internal Medicine and Radboud Center for Infectious Diseases, Radboud university medical center, Nijmegen, The Netherlands
| | - Arno C. Andeweg
- Department of Viroscience, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Frank J. M. van Kuppeveld
- Virology Division, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, University of Utrecht, Utrecht, The Netherlands
| | - Martijn A. Huynen
- Centre for Molecular and Biomolecular Informatics, Radboud Institute for Molecular Life Sciences, Radboud university medical center, Nijmegen, The Netherlands
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76
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Lum FM, Ng LF. Cellular and molecular mechanisms of chikungunya pathogenesis. Antiviral Res 2015; 120:165-74. [DOI: 10.1016/j.antiviral.2015.06.009] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 05/27/2015] [Accepted: 06/16/2015] [Indexed: 12/15/2022]
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77
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van ‘t Wout EFA, van Schadewijk A, van Boxtel R, Dalton LE, Clarke HJ, Tommassen J, Marciniak SJ, Hiemstra PS. Virulence Factors of Pseudomonas aeruginosa Induce Both the Unfolded Protein and Integrated Stress Responses in Airway Epithelial Cells. PLoS Pathog 2015; 11:e1004946. [PMID: 26083346 PMCID: PMC4471080 DOI: 10.1371/journal.ppat.1004946] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Accepted: 05/11/2015] [Indexed: 12/20/2022] Open
Abstract
Pseudomonas aeruginosa infection can be disastrous in chronic lung diseases such as cystic fibrosis and chronic obstructive pulmonary disease. Its toxic effects are largely mediated by secreted virulence factors including pyocyanin, elastase and alkaline protease (AprA). Efficient functioning of the endoplasmic reticulum (ER) is crucial for cell survival and appropriate immune responses, while an excess of unfolded proteins within the ER leads to “ER stress” and activation of the “unfolded protein response” (UPR). Bacterial infection and Toll-like receptor activation trigger the UPR most likely due to the increased demand for protein folding of inflammatory mediators. In this study, we show that cell-free conditioned medium of the PAO1 strain of P. aeruginosa, containing secreted virulence factors, induces ER stress in primary bronchial epithelial cells as evidenced by splicing of XBP1 mRNA and induction of CHOP, GRP78 and GADD34 expression. Most aspects of the ER stress response were dependent on TAK1 and p38 MAPK, except for the induction of GADD34 mRNA. Using various mutant strains and purified virulence factors, we identified pyocyanin and AprA as inducers of ER stress. However, the induction of GADD34 was mediated by an ER stress-independent integrated stress response (ISR) which was at least partly dependent on the iron-sensing eIF2α kinase HRI. Our data strongly suggest that this increased GADD34 expression served to protect against Pseudomonas-induced, iron-sensitive cell cytotoxicity. In summary, virulence factors from P. aeruginosa induce ER stress in airway epithelial cells and also trigger the ISR to improve cell survival of the host. Pseudomonas aeruginosa causes a devastating infection when it affects patients with cystic fibrosis or other chronic lung diseases. It often causes chronic infection due to its resistance to antibiotic treatment and its ability to form biofilms in these patients. The toxic effects of P. aeruginosa are largely mediated by secreted virulence factors. Efficient functioning of the endoplasmic reticulum is crucial for cell survival and appropriate immune responses, while its dysfunction causes stress and activation of the unfolded protein response. In this study, we found that virulence factors secreted by P. aeruginosa trigger the unfolded protein response in human cells by causing endoplasmic reticulum stress. In addition, secreted virulence factors activate the integrated stress response via a parallel independent pathway. Both stress pathways lead to the induction of the protein GADD34, which appears to provide protection against the toxic effects of the secreted virulence factors.
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Affiliation(s)
- Emily F. A. van ‘t Wout
- Department of Pulmonology, Leiden University Medical Centre, Leiden, the Netherlands
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | | | - Ria van Boxtel
- Department of Molecular Microbiology, Utrecht University, Utrecht, the Netherlands
| | - Lucy E. Dalton
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | - Hanna J. Clarke
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | - Jan Tommassen
- Department of Molecular Microbiology, Utrecht University, Utrecht, the Netherlands
| | - Stefan J. Marciniak
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, United Kingdom
| | - Pieter S. Hiemstra
- Department of Pulmonology, Leiden University Medical Centre, Leiden, the Netherlands
- * E-mail:
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78
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Dalet A, Gatti E, Pierre P. Integration of PKR-dependent translation inhibition with innate immunity is required for a coordinated anti-viral response. FEBS Lett 2015; 589:1539-45. [PMID: 25979169 DOI: 10.1016/j.febslet.2015.05.006] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 04/29/2015] [Accepted: 05/02/2015] [Indexed: 01/26/2023]
Abstract
Viral triggering of the innate immune response in infected cells aims at delaying viral replication and prevents tissue spreading. Viral replication is delayed by host protein synthesis inhibition and infected cell apoptosis on one hand, while infection spreading is controlled by the synthesis of specific proteins like type-I interferons (IFNs) and pro-inflammatory cytokines on the other hand. How do these two apparent conflicting responses cooperate within the same infected cells to mount effective defenses against pathogens? What are the molecules or the complexes resolving this contradiction over time? Some recent studies reveal unanticipated connections between innate immunity and stress pathways, giving important clues on how the cellular responses are orchestrated to limit infection efficiently.
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Affiliation(s)
- Alexandre Dalet
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288 Marseille, France
| | - Evelina Gatti
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Philippe Pierre
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université UM2, Inserm, U1104, CNRS UMR7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
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79
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Argüello RJ, Rodriguez Rodrigues C, Gatti E, Pierre P. Protein synthesis regulation, a pillar of strength for innate immunity? Curr Opin Immunol 2014; 32:28-35. [PMID: 25553394 DOI: 10.1016/j.coi.2014.12.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 12/04/2014] [Accepted: 12/10/2014] [Indexed: 12/31/2022]
Abstract
Recognition of pathogen derived molecules by Pattern Recognition Receptors (PRR) induces the production of cytokines (i.e. type I interferons) that stimulate the surrounding cells to transcribe and translate hundreds of genes, in order to prevent further infection and organize the immune response. Here, we report on the rising matter that metabolism sensing and gene expression control at the level of mRNA translation, allow swift responses that mobilize host defenses and coordinate innate responses to infection.
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Affiliation(s)
- Rafael J Argüello
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France
| | - Christian Rodriguez Rodrigues
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France
| | - Evelina Gatti
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
| | - Philippe Pierre
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, U2M, 13288 Marseille, France; INSERM, U1104, 13288 Marseille, France; CNRS, UMR 7280, 13288 Marseille, France; Institute for Research in Biomedicine - iBiMED and Aveiro Health Sciences Program, University of Aveiro, 3810-193 Aveiro, Portugal.
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80
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Fung TS, Huang M, Liu DX. Coronavirus-induced ER stress response and its involvement in regulation of coronavirus-host interactions. Virus Res 2014; 194:110-23. [PMID: 25304691 PMCID: PMC7114476 DOI: 10.1016/j.virusres.2014.09.016] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 09/25/2014] [Accepted: 09/28/2014] [Indexed: 12/11/2022]
Abstract
Coronavirus replication is structurally and functionally associated with the endoplasmic reticulum (ER), a major site of protein synthesis, folding, modification and sorting in the eukaryotic cells. Disturbance of ER homeostasis may occur under various physiological or pathological conditions. In response to the ER stress, signaling pathways of the unfolded protein response (UPR) are activated. UPR is mediated by three ER transmembrane sensors, namely the PKR-like ER protein kinase (PERK), the inositol-requiring protein 1 (IRE1) and the activating transcriptional factor 6 (ATF6). UPR facilitates adaptation to ER stress by reversible translation attenuation, enhancement of ER protein folding capacity and activation of ER-associated degradation (ERAD). In cells under prolonged and irremediable ER stress, UPR can also trigger apoptotic cell death. Accumulating evidence has shown that coronavirus infection causes ER stress and induces UPR in the infected cells. UPR is closely associated with a number of major signaling pathways, including autophagy, apoptosis, the mitogen-activated protein (MAP) kinase pathways, innate immunity and pro-inflammatory response. Therefore, studies on the UPR are pivotal in elucidating the complicated issue of coronavirus-host interaction. In this paper, we present the up-to-date knowledge on coronavirus-induced UPR and discuss its potential involvement in regulation of innate immunity and apoptosis.
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Affiliation(s)
- To Sing Fung
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Mei Huang
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551
| | - Ding Xiang Liu
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551.
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81
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Emerging functions of the unfolded protein response in immunity. Nat Immunol 2014; 15:910-9. [PMID: 25232821 DOI: 10.1038/ni.2991] [Citation(s) in RCA: 170] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 08/18/2014] [Indexed: 12/14/2022]
Abstract
The unfolded protein response (UPR) has traditionally been viewed as an adaptive response triggered by the accumulation of unfolded proteins in the endoplasmic reticulum (ER) and aimed at restoring ER function. The UPR can also be an anticipatory response that is activated well before the disruption of protein homeostasis. UPR signaling intersects at many levels with the innate and adaptive immune responses. In some types of cells of the immune system, such as dendritic cells (DCs) and B cells, particular sensors that detect the UPR seem to be constitutively active in the absence of induction of the traditional UPR gene program and are necessary for antigen presentation and immunoglobulin synthesis. The UPR also influences signaling via Toll-like receptors (TLRs) and activation of the transcription factor NF-κB, and some pathogens subvert the UPR. This Review summarizes these emerging noncanonical functions of the UPR in immunity.
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82
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van’t Wout EF, van Schadewijk A, Lomas DA, Stolk J, Marciniak SJ, Hiemstra PS. Function of monocytes and monocyte-derived macrophages in α1-antitrypsin deficiency. Eur Respir J 2014; 45:365-76. [DOI: 10.1183/09031936.00046114] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
α1-antitrypsin deficiency is the most widely recognised genetic disorder causing chronic obstructive pulmonary disease (COPD). Mutant Z α1-antitrypsin expression has previously been linked to intracellular accumulation and polymerisation of this proteinase inhibitor. Subsequently, this has been described to underlie an exaggerated endoplasmic reticulum stress response and enhanced nuclear factor-κB signalling. However, whether monocyte-derived macrophages display the same features remains unknown.Monocytes from homozygous PiZZ α1-antitrypsin deficiency patients and PiMM controls were cultured for 6 days in the presence of granulocyte-macrophage or macrophage colony-stimulating factor to obtain pro- and anti-inflammatory macrophages (mφ-1 and mφ-2, respectively).We first showed that, in contrast to monocytes, pre-stressed mφ-1 and mφ-2 from healthy blood donors display an enhanced endoplasmic reticulum stress response upon a lipopolysaccharide trigger (XBP1 splicing, CHOP, GADD34 and GRP78 mRNA). However, this endoplasmic reticulum stress response did not differ between monocyte-derived macrophages and monocytes from ZZ patients compared to MM controls. Furthermore, these ZZ cells do not secrete higher cytokine levels, and α1-antitrypsin polymers were not detectable by ELISA.These data suggest that monocyte-derived macrophages are not the local source of Z α1-antitrypsin polymers found in the lung and that endoplasmic reticulum stress and pro-inflammatory cytokine release is not altered.
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83
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van 't Wout EFA, Hiemstra PS, Marciniak SJ. The integrated stress response in lung disease. Am J Respir Cell Mol Biol 2014; 50:1005-9. [PMID: 24605820 DOI: 10.1165/rcmb.2014-0019tr] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Lungs are repeatedly exposed to inhaled toxic insults, such as smoke, diesel exhaust, and microbes, which elicit cellular stress responses. The phosphorylation of eukaryotic translation initiation factor 2α by one of four stress-sensing kinases triggers a pathway called the integrated stress response that helps protect cellular reserves of nutrients and prevents the accumulation of toxic proteins. In this review, we discuss how activation of the integrated stress response has been shown to play an important role in pulmonary pathology, and how its study may help in the development of novel therapies for diverse conditions, from hypoxia to cancer.
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Affiliation(s)
- Emily F A van 't Wout
- 1 Department of Pulmonology, Leiden University Medical Centre, Leiden, the Netherlands; and
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84
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Mesman AW, Zijlstra-Willems EM, Kaptein TM, de Swart RL, Davis ME, Ludlow M, Duprex WP, Gack MU, Gringhuis SI, Geijtenbeek TBH. Measles virus suppresses RIG-I-like receptor activation in dendritic cells via DC-SIGN-mediated inhibition of PP1 phosphatases. Cell Host Microbe 2014; 16:31-42. [PMID: 25011106 PMCID: PMC4159752 DOI: 10.1016/j.chom.2014.06.008] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2014] [Revised: 04/02/2014] [Accepted: 05/21/2014] [Indexed: 12/12/2022]
Abstract
Dendritic cells (DCs) are targets of measles virus (MV) and play central roles in viral dissemination. However, DCs express the RIG-I-like receptors (RLRs) RIG-I and Mda5 that sense MV and induce type I interferon (IFN) production. Given the potency of this antiviral response, RLRs are tightly regulated at various steps, including dephosphorylation by PP1 phosphatases, which induces their activation. We demonstrate that MV suppresses RIG-I and Mda5 by activating the C-type lectin DC-SIGN and inducing signaling that prevents RLR dephosphorylation. MV binding to DC-SIGN leads to activation of the kinase Raf-1, which induces the association of PP1 inhibitor I-1 with GADD34-PP1 holoenzymes, thereby inhibiting phosphatase activity. Consequently, GADD34-PP1 holoenzymes are unable to dephosphorylate RIG-I and Mda5, hence suppressing type I IFN responses and enhancing MV replication. Blocking DC-SIGN signaling allows RLR activation and suppresses MV infection of DCs. Thus, MV subverts DC-SIGN to control RLR activation and escape antiviral responses.
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Affiliation(s)
- Annelies W Mesman
- Department of Experimental Immunology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands
| | - Esther M Zijlstra-Willems
- Department of Experimental Immunology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands
| | - Tanja M Kaptein
- Department of Experimental Immunology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands
| | - Rik L de Swart
- Department of Virology, Erasmus MC, 's-Gravendijkwal 230, 3015 CA Rotterdam, the Netherlands
| | - Meredith E Davis
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Martin Ludlow
- Department of Microbiology, Boston University, School of Medicine, Boston, MA 02118, USA
| | - W Paul Duprex
- Department of Microbiology, Boston University, School of Medicine, Boston, MA 02118, USA
| | - Michaela U Gack
- Department of Microbiology and Immunobiology, Harvard Medical School, Boston, MA 02115, USA
| | - Sonja I Gringhuis
- Department of Experimental Immunology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands.
| | - Teunis B H Geijtenbeek
- Department of Experimental Immunology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, the Netherlands.
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85
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Rao J, Yue S, Fu Y, Zhu J, Wang X, Busuttil RW, Kupiec-Weglinski JW, Lu L, Zhai Y. ATF6 mediates a pro-inflammatory synergy between ER stress and TLR activation in the pathogenesis of liver ischemia-reperfusion injury. Am J Transplant 2014; 14:1552-61. [PMID: 24903305 PMCID: PMC4074706 DOI: 10.1111/ajt.12711] [Citation(s) in RCA: 126] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Revised: 02/07/2014] [Accepted: 02/15/2014] [Indexed: 01/25/2023]
Abstract
Although the roles of the metabolic stress in organ ischemia-reperfusion injury (IRI) have been well recognized, the question of whether and how these stress responses regulate innate immune activation against IR remains unclear. In a murine liver partial warm ischemia mode, we showed that prolonged ischemia triggered endoplasmic reticulum (ER) stress response, particularly, the activating transcription factor 6 (ATF6) branch, in liver Kupffer cells (KCs) and altered their responsiveness against Toll-like receptor (TLR) stimulation. Ischemia-primed cells increased pro-, but decreased anti-, inflammatory cytokine productions. Alleviation of ER stress in vivo by small chemical chaperon 4-phenylbutyrate or ATF6 small interfering RNA (siRNA) diminished the pro-inflammatory priming effect of ischemia in KCs, leading to the inhibition of liver immune response against IR and protection of livers from IRI. In vitro, ATF6 siRNA abrogated the ER stress-mediated pro-inflammatory enhancement of macrophage TLR4 response, by restricting NF-κB and restoring Akt activations. Thus, ischemia primes liver innate immune cells by ATF6-mediated ER stress response. The IR-induced metabolic stress and TLR activation function in synergy to activate tissue inflammatory immune response.
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Affiliation(s)
- Jianhua Rao
- Dumont-UCLA Transplant Center, Division of Liver and Pancreas Transplantation, Department of Surgery, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, CA, USA,Department of Liver Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiansu Province, China
| | - Shi Yue
- Dumont-UCLA Transplant Center, Division of Liver and Pancreas Transplantation, Department of Surgery, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, CA, USA
| | - Yuanfang Fu
- Dumont-UCLA Transplant Center, Division of Liver and Pancreas Transplantation, Department of Surgery, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, CA, USA
| | - Jianjun Zhu
- Dumont-UCLA Transplant Center, Division of Liver and Pancreas Transplantation, Department of Surgery, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, CA, USA,Department of Liver Surgery, Renji Hospital, Shanghai Jiaotong University Medical School, Shanghai, China
| | - Xuehao Wang
- Department of Liver Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiansu Province, China
| | - Ronald W. Busuttil
- Dumont-UCLA Transplant Center, Division of Liver and Pancreas Transplantation, Department of Surgery, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, CA, USA
| | - Jerzy W. Kupiec-Weglinski
- Dumont-UCLA Transplant Center, Division of Liver and Pancreas Transplantation, Department of Surgery, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, CA, USA
| | - Ling Lu
- Department of Liver Surgery, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiansu Province, China,Address correspondence: Yuan Zhai, MD, PhD. Dumont-UCLA Transplant Center 77-120 CHS, 10833 Le Conte Ave, Los Angeles, CA 90095. Phone: (310) 825-9426; Fax: (310) 267-2367, ; Ling Lu, MD, Department of Liver Surgery, The First Affiliated Hospital of Nanjing Medical University, 300 Guanzhou Road, Nanjing, P.R.China, Phone: 86-25-68136053; Fax:86-25-84630769;
| | - Yuan Zhai
- Dumont-UCLA Transplant Center, Division of Liver and Pancreas Transplantation, Department of Surgery, David Geffen School of Medicine at University of California-Los Angeles, Los Angeles, CA, USA,Address correspondence: Yuan Zhai, MD, PhD. Dumont-UCLA Transplant Center 77-120 CHS, 10833 Le Conte Ave, Los Angeles, CA 90095. Phone: (310) 825-9426; Fax: (310) 267-2367, ; Ling Lu, MD, Department of Liver Surgery, The First Affiliated Hospital of Nanjing Medical University, 300 Guanzhou Road, Nanjing, P.R.China, Phone: 86-25-68136053; Fax:86-25-84630769;
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86
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Chan SW. Unfolded protein response in hepatitis C virus infection. Front Microbiol 2014; 5:233. [PMID: 24904547 PMCID: PMC4033015 DOI: 10.3389/fmicb.2014.00233] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 04/30/2014] [Indexed: 12/14/2022] Open
Abstract
Hepatitis C virus (HCV) is a single-stranded, positive-sense RNA virus of clinical importance. The virus establishes a chronic infection and can progress from chronic hepatitis, steatosis to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). The mechanisms of viral persistence and pathogenesis are poorly understood. Recently the unfolded protein response (UPR), a cellular homeostatic response to endoplasmic reticulum (ER) stress, has emerged to be a major contributing factor in many human diseases. It is also evident that viruses interact with the host UPR in many different ways and the outcome could be pro-viral, anti-viral or pathogenic, depending on the particular type of infection. Here we present evidence for the elicitation of chronic ER stress in HCV infection. We analyze the UPR signaling pathways involved in HCV infection, the various levels of UPR regulation by different viral proteins and finally, we propose several mechanisms by which the virus provokes the UPR.
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Affiliation(s)
- Shiu-Wan Chan
- Faculty of Life Sciences, The University of Manchester Manchester, UK
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87
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Smith JA. A new paradigm: innate immune sensing of viruses via the unfolded protein response. Front Microbiol 2014; 5:222. [PMID: 24904537 PMCID: PMC4032990 DOI: 10.3389/fmicb.2014.00222] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2014] [Accepted: 04/27/2014] [Indexed: 12/17/2022] Open
Abstract
The immune system depends upon combinations of signals to mount appropriate responses: pathogen specific signals in the context of co-stimulatory “danger” signals drive immune strength and accuracy. Viral infections trigger anti-viral type I interferon (IFN) responses by stimulating endosomal and cytosolic pattern recognition receptors (PRRs). However, viruses have also evolved many strategies to counteract IFN responses. Are there intracellular danger signals that enhance immune responses to viruses? During infection, viruses place a heavy demand on the protein folding machinery of the host endoplasmic reticulum (ER). To survive ER stress, host cells mount an unfolded protein response (UPR) to decrease ER protein load and enhance protein-folding capacity. Viruses also directly elicit the UPR to enhance their replication. Increasing evidence supports an intersection between the host UPR and inflammation, in particular the production of pro-inflammatory cytokines and type I IFN. The UPR directly activates pro-inflammatory cytokine transcription factors and dramatically enhances cytokine production in response to viral PRR engagement. Additionally, viral PRR engagement may stimulate specific pathways within the UPR to enhance cytokine production. Through these mechanisms, viral detection via the UPR and inflammatory cytokine production are intertwined. Consequently, the UPR response is perfectly poised to act as an infection-triggered “danger” signal. The UPR may serve as an internal “co-stimulatory” signal that (1) provides specificity and (2) critically augments responses to overcome viral subterfuge. Further work is needed to test this hypothesis during viral infections.
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Affiliation(s)
- Judith A Smith
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health Madison, WI, USA
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88
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Cláudio N, Dalet A, Gatti E, Pierre P. Mapping the crossroads of immune activation and cellular stress response pathways. EMBO J 2013; 32:1214-24. [PMID: 23584529 DOI: 10.1038/emboj.2013.80] [Citation(s) in RCA: 101] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2013] [Accepted: 03/15/2013] [Indexed: 12/14/2022] Open
Abstract
The innate immune cell network detects specific microbes and damages to cell integrity in order to coordinate and polarize the immune response against invading pathogens. In recent years, a cross-talk between microbial-sensing pathways and endoplasmic reticulum (ER) homeostasis has been discovered and have attracted the attention of many researchers from the inflammation field. Abnormal accumulation of proteins in the ER can be seen as a sign of cellular malfunction and triggers a collection of conserved emergency rescue pathways. These signalling cascades, which increase ER homeostasis and favour cell survival, are collectively known as the unfolded protein response (UPR). The induction or activation by microbial stimuli of several molecules linked to the ER stress response pathway have led to the conclusion that microbe sensing by immunocytes is generally associated with an UPR, which serves as a signal amplification cascade favouring inflammatory cytokines production. Induction of the UPR alone was shown to promote inflammation in different cellular and pathological models. Here we discuss how the innate immune and ER-signalling pathways intersect. Moreover, we propose that the induction of UPR-related molecules by microbial products does not necessarily reflect ER stress, but instead is an integral part of a specific transcription programme controlled by innate immunity receptors.
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Affiliation(s)
- Nuno Cláudio
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille Université, UM2, Marseille, France
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89
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MDA5 localizes to stress granules, but this localization is not required for the induction of type I interferon. J Virol 2013; 87:6314-25. [PMID: 23536668 DOI: 10.1128/jvi.03213-12] [Citation(s) in RCA: 83] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Virus infection can initiate a type I interferon (IFN-α/β) response via activation of the cytosolic RNA sensors retinoic acid-inducible gene-I (RIG-I) and melanoma differentiation-associated gene 5 (MDA5). Furthermore, it can activate kinases that phosphorylate eukaryotic translation initiation factor 2α (eIF2α), which leads to inhibition of (viral) protein translation and formation of stress granules (SG). Most viruses have evolved mechanisms to suppress these cellular responses. Here, we show that a mutant mengovirus expressing an inactive leader (L) protein, which we have previously shown to be unable to suppress IFN-α/β, triggered SG formation in a protein kinase R (PKR)-dependent manner. Furthermore, we show that infection of cells that are defective in SG formation yielded higher viral RNA levels, suggesting that SG formation acts as an antiviral defense mechanism. Since the induction of both IFN-α/β and SG is suppressed by mengovirus L, we set out to investigate a potential link between these pathways. We observed that MDA5, the intracellular RNA sensor that recognizes picornaviruses, localized to SG. However, activation of the MDA5 signaling pathway did not trigger and was not required for SG formation. Moreover, cells that were unable to form SG-by protein kinase R (PKR) depletion, using cells expressing a nonphosphorylatable eIF2α protein, or by drug treatment that inhibits SG formation-displayed a normal IFN-α/β response. Thus, although MDA5 localizes to SG, this localization seems to be dispensable for induction of the IFN-α/β pathway.
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90
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Abstract
Chikungunya virus (CHIKV) is a mosquito-borne alphavirus responsible for recent epidemic outbreaks of debilitating disease in humans. Alphaviruses are known to interact with members of the C-type lectin receptor family of pattern recognition proteins, and given that the dendritic cell immunoreceptor (DCIR) is known to act as a negative regulator of the host inflammatory response and has previously been associated with rheumatoid arthritis, we evaluated DCIR's role in response to CHIKV infection. Although we observed an increase in the proportion of dendritic cells at the site of CHIKV infection at 24 to 36 h postinfection, these cells showed decreased cell surface DCIR, suggestive of DCIR triggering and internalization. In vitro, bone marrow-derived dendritic cells from DCIR-deficient (DCIR(-/-)) mice exhibited altered cytokine expression following exposure to CHIKV. DCIR(-/-) mice exhibited more severe disease signs than wild-type C57BL6/J mice following CHIKV infection, including a more rapid and more severe onset of virus-induced edema and enhanced weight loss. Histological examination revealed that DCIR-deficient animals exhibited increased inflammation and damage in both the fascia of the inoculated foot and the ankle joint, and DCIR deficiency skewed the CHIKV-induced cytokine response at the site of infection at multiple times postinfection. Early differences in virus-induced disease between C57BL6/J and DCIR(-/-) mice were independent of viral replication, while extended viral replication correlated with enhanced foot swelling and tissue inflammation and damage in DCIR(-/-) compared to C57BL6/J mice at 6 to 7 days postinfection. These results suggest that DCIR plays a protective role in limiting the CHIKV-induced inflammatory response and subsequent tissue and joint damage.
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91
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Balakrishnan B, Sen D, Hareendran S, Roshini V, David S, Srivastava A, Jayandharan GR. Activation of the cellular unfolded protein response by recombinant adeno-associated virus vectors. PLoS One 2013; 8:e53845. [PMID: 23320106 PMCID: PMC3540029 DOI: 10.1371/journal.pone.0053845] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2012] [Accepted: 12/05/2012] [Indexed: 12/11/2022] Open
Abstract
The unfolded protein response (UPR) is a stress-induced cyto-protective mechanism elicited towards an influx of large amount of proteins in the endoplasmic reticulum (ER). In the present study, we evaluated if AAV manipulates the UPR pathways during its infection. We first examined the role of the three major UPR axes, namely, endoribonuclease inositol-requiring enzyme-1 (IRE1α), activating transcription factor 6 (ATF6) and PKR-like ER kinase (PERK) in AAV infected cells. Total RNA from mock or AAV infected HeLa cells were used to determine the levels of 8 different ER-stress responsive transcripts from these pathways. We observed a significant up-regulation of IRE1α (up to 11 fold) and PERK (up to 8 fold) genes 12–48 hours after infection with self-complementary (sc)AAV2 but less prominent with single-stranded (ss)AAV2 vectors. Further studies demonstrated that scAAV1 and scAAV6 also induce cellular UPR in vitro, with AAV1 vectors activating the PERK pathway (3 fold) while AAV6 vectors induced a significant increase on all the three major UPR pathways [6–16 fold]. These data suggest that the type and strength of UPR activation is dependent on the viral capsid. We then examined if transient inhibition of UPR pathways by RNA interference has an effect on AAV transduction. siRNA mediated silencing of PERK and IRE1α had a modest effect on AAV2 and AAV6 mediated gene expression (∼1.5–2 fold) in vitro. Furthermore, hepatic gene transfer of scAAV2 vectors in vivo, strongly elevated IRE1α and PERK pathways (2 and 3.5 fold, respectively). However, when animals were pre-treated with a pharmacological UPR inhibitor (metformin) during scAAV2 gene transfer, the UPR signalling and its subsequent inflammatory response was attenuated concomitant to a modest 2.8 fold increase in transgene expression. Collectively, these data suggest that AAV vectors activate the cellular UPR pathways and their selective inhibition may be beneficial during AAV mediated gene transfer.
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Affiliation(s)
- Balaji Balakrishnan
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Dwaipayan Sen
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Sangeetha Hareendran
- Centre for Stem Cell Research, Christian Medical College, Vellore, Tamil Nadu, India
| | - Vaani Roshini
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Sachin David
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
| | - Alok Srivastava
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
- Centre for Stem Cell Research, Christian Medical College, Vellore, Tamil Nadu, India
| | - Giridhara R. Jayandharan
- Department of Hematology, Christian Medical College, Vellore, Tamil Nadu, India
- Centre for Stem Cell Research, Christian Medical College, Vellore, Tamil Nadu, India
- * E-mail:
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92
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Lazear HM, Lancaster A, Wilkins C, Suthar MS, Huang A, Vick SC, Clepper L, Thackray L, Brassil MM, Virgin HW, Nikolich-Zugich J, Moses AV, Gale M, Früh K, Diamond MS. IRF-3, IRF-5, and IRF-7 coordinately regulate the type I IFN response in myeloid dendritic cells downstream of MAVS signaling. PLoS Pathog 2013; 9:e1003118. [PMID: 23300459 PMCID: PMC3536698 DOI: 10.1371/journal.ppat.1003118] [Citation(s) in RCA: 228] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2012] [Accepted: 11/23/2012] [Indexed: 12/11/2022] Open
Abstract
Although the transcription factors IRF-3 and IRF-7 are considered master regulators of type I interferon (IFN) induction and IFN stimulated gene (ISG) expression, Irf3−/−×Irf7−/− double knockout (DKO) myeloid dendritic cells (mDC) produce relatively normal levels of IFN-β after viral infection. We generated Irf3−/−×Irf5−/−×Irf7−/− triple knockout (TKO) mice to test whether IRF-5 was the source of the residual induction of IFN-β and ISGs in mDCs. In pathogenesis studies with two unrelated positive-sense RNA viruses (West Nile virus (WNV) and murine norovirus), TKO mice succumbed at rates greater than DKO mice and equal to or approaching those of mice lacking the type I IFN receptor (Ifnar−/−). In ex vivo studies, after WNV infection or exposure to Toll-like receptor agonists, TKO mDCs failed to produce IFN-β or express ISGs. In contrast, this response was sustained in TKO macrophages following WNV infection. To define IRF-regulated gene signatures, we performed microarray analysis on WNV-infected mDC from wild type (WT), DKO, TKO, or Ifnar−/− mice, as well as from mice lacking the RIG-I like receptor adaptor protein MAVS. Whereas the gene induction pattern in DKO mDC was similar to WT cells, remarkably, almost no ISG induction was detected in TKO or Mavs−/− mDC. The relative equivalence of TKO and Mavs−/− responses suggested that MAVS dominantly regulates ISG induction in mDC. Moreover, we showed that MAVS-dependent induction of ISGs can occur through an IRF-5-dependent yet IRF-3 and IRF-7-independent pathway. Our results establish IRF-3, -5, and -7 as the key transcription factors responsible for mediating the type I IFN and ISG response in mDC during WNV infection and suggest a novel signaling link between MAVS and IRF-5. Host pathogen sensors, including those of the Toll-like receptor and RIG-I like receptor (RLR) families, detect viral infection in cells. Signaling through these receptors triggers expression of type I interferon (IFN) and IFN-stimulated genes (ISGs), in part through the IRF family of transcription factors. Previous studies with West Nile virus (WNV) showed that IRF-3 and IRF-7 control IFN expression in fibroblasts and neurons, whereas macrophages and myeloid dendritic cells (mDC) retained the ability to induce IFN-β without IRF-3 and IRF-7. In the current study, we generated Irf3−/−×Irf5−/−×Irf7−/− (TKO) mice to characterize the contributions of specific IRF transcription factors to IFN and ISG induction in response to WNV infection in cells and in mice. We found that induction of IFN and ISGs was largely abolished in TKO mDC, but sustained in TKO macrophages. Because IFN and ISG induction also was absent in mDC lacking MAVS, a key mediator of RLR signaling, our results suggest a novel signaling link between IRF-5 and MAVS. This study establishes the molecular pathways responsible for IFN induction in mDC and suggests a cross-talk between IRF-5 and RLR signaling pathways.
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Affiliation(s)
- Helen M. Lazear
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Alissa Lancaster
- Vaccine and Gene Therapy Institute, Oregon Health and Sciences University, Beaverton, Oregon, United States of America
| | - Courtney Wilkins
- University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Mehul S. Suthar
- University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Albert Huang
- University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Sarah C. Vick
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Lisa Clepper
- Vaccine and Gene Therapy Institute, Oregon Health and Sciences University, Beaverton, Oregon, United States of America
| | - Larissa Thackray
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Margaret M. Brassil
- University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Herbert W. Virgin
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Janko Nikolich-Zugich
- Department of Immunobiology and the Arizona Center on Aging, University of Arizona College of Medicine, Tucson, Arizona, United States of America
| | - Ashlee V. Moses
- Vaccine and Gene Therapy Institute, Oregon Health and Sciences University, Beaverton, Oregon, United States of America
| | - Michael Gale
- University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Klaus Früh
- Vaccine and Gene Therapy Institute, Oregon Health and Sciences University, Beaverton, Oregon, United States of America
| | - Michael S. Diamond
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
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Teng TS, Foo SS, Simamarta D, Lum FM, Teo TH, Lulla A, Yeo NKW, Koh EGL, Chow A, Leo YS, Merits A, Chin KC, Ng LFP. Viperin restricts chikungunya virus replication and pathology. J Clin Invest 2012; 122:4447-60. [PMID: 23160199 DOI: 10.1172/jci63120] [Citation(s) in RCA: 146] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 09/20/2012] [Indexed: 12/15/2022] Open
Abstract
Chikungunya virus (CHIKV) is a mosquito-borne arthralgia arbovirus that is reemergent in sub-Saharan Africa and Southeast Asia. CHIKV infection has been shown to be self-limiting, but the molecular mechanisms of the innate immune response that control CHIKV replication remain undefined. Here, longitudinal transcriptional analyses of PBMCs from a cohort of CHIKV-infected patients revealed that type I IFNs controlled CHIKV infection via RSAD2 (which encodes viperin), an enigmatic multifunctional IFN-stimulated gene (ISG). Viperin was highly induced in monocytes, the major target cell of CHIKV in blood. Anti-CHIKV functions of viperin were dependent on its localization in the ER, and the N-terminal amphipathic α-helical domain was crucial for its antiviral activity in controlling CHIKV replication. Furthermore, mice lacking Rsad2 had higher viremia and severe joint inflammation compared with wild-type mice. Our data demonstrate that viperin is a critical antiviral host protein that controls CHIKV infection and provide a preclinical basis for the design of effective control strategies against CHIKV and other reemerging arthrogenic alphaviruses.
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Affiliation(s)
- Terk-Shin Teng
- Singapore Immunology Network, Agency for Science, Technology and Research (A*STAR), Biopolis, Singapore
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