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Shiratori T, Imaizumi T, Hirono K, Kawaguchi S, Matsumiya T, Seya K, Tasaka S. ISG56 is involved in CXCL10 expression induced by TLR3 signaling in BEAS-2B bronchial epithelial cells. Exp Lung Res 2020; 46:195-202. [PMID: 32363951 DOI: 10.1080/01902148.2020.1760965] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Purpose and aim of the study: Bronchial epithelial cells play an important role in immune response against viral infections. Toll-like receptor 3 (TLR3) is a pathogen recognition receptor that recognizes viral double-stranded RNA (dsRNA). Activation of TLR3 induces the expression of interferon (IFN)-β, and newly synthesized IFN-β exhibits anti-viral activity by upregulating the expression of IFN-stimulated genes (ISGs). ISG56 encodes a multifunctional protein with tetratricopeptide motifs and is involved in anti-viral reactions through various mechanisms. Expression of chemokines such as CXCL10, which induces leukocyte chemotaxis, is essential for defense against airway microbes. However, regulation of chemokine expression by ISG56 in bronchial epithelial cells has not been fully investigated. The aim of this study was to examine the expression of ISG56 and its role in CXCL10 production in BEAS-2B bronchial epithelial cells treated with dsRNA.Materials and methods: BEAS-2B bronchial epithelial cells were treated with polyinosinic-polycytidylic acid (poly IC), a synthetic TLR3 ligand. The mRNA and protein expression levels of ISG 56 were analyzed by quantitative reverse transcription polymerase chain reaction and western blotting. The effect of knocking down TLR3, IFN-β, and ISG56 was examined using RNA interference. The protein expression of CXCL10 in culture medium was measured using an enzyme-linked immunosorbent assay.Results: Poly IC induced ISG56 expression in a concentration- and time- dependent manner. RNA interference showed that ISG56 induction was inhibited by knockdown of TLR3 or IFN-β and that ISG 56 knockdown decreased CXCL10 expression.Conclusions: ISG56 was induced by poly IC through TLR3/IFN-β axis, and ISG56 may positively regulated CXCL10 expression in BEAS-2B cells. ISG56 may modulate anti-viral innate immunity, at least in part, by regulating the expression of CXCL10 in bronchial epithelial cells.
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Affiliation(s)
- Toshihiro Shiratori
- Department of Respiratory Medicine, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Tadaatsu Imaizumi
- Department of Vascular Biology, Institute of Brain Science, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Koji Hirono
- Department of Pediatrics, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Shogo Kawaguchi
- Department of Vascular Biology, Institute of Brain Science, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Tomoh Matsumiya
- Department of Vascular Biology, Institute of Brain Science, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Kazuhiko Seya
- Department of Vascular Biology, Institute of Brain Science, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Sadatomo Tasaka
- Department of Respiratory Medicine, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
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Albano GD, Bonanno A, Giacomazza D, Cavalieri L, Sammarco M, Ingrassia E, Gagliardo R, Riccobono L, Moscato M, Anzalone G, Montalbano AM, Profita M. A 3D " In Vitro" Model to Study Hyaluronan Effect in Nasal Epithelial Cell Line Exposed to Double-Stranded RNA Poly(I:C). Biomol Ther (Seoul) 2020; 28:272-281. [PMID: 31791117 PMCID: PMC7216748 DOI: 10.4062/biomolther.2019.126] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/03/2019] [Accepted: 09/16/2019] [Indexed: 01/21/2023] Open
Abstract
Environmental agents, including viral and bacterial infectious agents, are involved in the alteration of physicochemical and biological parameters in the nasal epithelium. Hyaluronan (HA) has an important role in the regulation of tissue healing properties. High molecular weight HA (HMW-HA) shows greater anti-inflammatory responses than medium molecular weight HA (MMW-HA) and low molecular weight HA (LMW-HA). We investigated the effect of HMW-HA, MMW-HA and LMW-HA on the regulation of physicochemical and biological parameters in an “in vitro” model that might mimic viral infections of the nasal epithelium. Human nasal epithelial cell line RPMI2650 was stimulated with double-stranded RNA (dsRNA) Poly(I:C) for 5 days in air-liquid-interface (ALI) culture (3D model of airway tissue). dsRNA Poly(I:C) treatment significantly decreased transepithelial electrical resistance (TEER) in the stratified nasal epithelium of RPMI2650 and increased pH values, rheological parameters (elastic G’ and viscous G’’), and Muc5AC and Muc5B production in the apical wash of ALI culture of RPMI2650 in comparison to untreated cells. RPMI2650 treated with dsRNA Poly(I:C) in the presence of HMW-HA showed lower pH values, Muc5AC and Muc5B production, and rheological parameters, as well as increased TEER values in ALI culture, compared to cells treated with Poly(I:C) alone or pretreated with LMW-HA and MMW-HA. Our 3D “in vitro” model of epithelium suggests that HMW-HA might be a coadjuvant in the pharmacological treatment of viral infections, allowing for the control of some physicochemical and biological properties affecting the epithelial barrier of the nose during infection.
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Affiliation(s)
- Giusy Daniela Albano
- Institute for Biomedical Research and Innovation (IRIB), National Research Council of Italy (CNR), Palermo 90146, Italy
| | - Anna Bonanno
- Institute for Biomedical Research and Innovation (IRIB), National Research Council of Italy (CNR), Palermo 90146, Italy
| | | | | | | | | | - Rosalia Gagliardo
- Institute for Biomedical Research and Innovation (IRIB), National Research Council of Italy (CNR), Palermo 90146, Italy
| | - Loredana Riccobono
- Institute for Biomedical Research and Innovation (IRIB), National Research Council of Italy (CNR), Palermo 90146, Italy
| | - Monica Moscato
- Institute for Biomedical Research and Innovation (IRIB), National Research Council of Italy (CNR), Palermo 90146, Italy
| | - Giulia Anzalone
- Institute for Biomedical Research and Innovation (IRIB), National Research Council of Italy (CNR), Palermo 90146, Italy
| | - Angela Marina Montalbano
- Institute for Biomedical Research and Innovation (IRIB), National Research Council of Italy (CNR), Palermo 90146, Italy
| | - Mirella Profita
- Institute for Biomedical Research and Innovation (IRIB), National Research Council of Italy (CNR), Palermo 90146, Italy
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Ramos I, Smith G, Ruf-Zamojski F, Martínez-Romero C, Fribourg M, Carbajal EA, Hartmann BM, Nair VD, Marjanovic N, Monteagudo PL, DeJesus VA, Mutetwa T, Zamojski M, Tan GS, Jayaprakash C, Zaslavsky E, Albrecht RA, Sealfon SC, García-Sastre A, Fernandez-Sesma A. Innate Immune Response to Influenza Virus at Single-Cell Resolution in Human Epithelial Cells Revealed Paracrine Induction of Interferon Lambda 1. J Virol 2019; 93:e00559-19. [PMID: 31375585 PMCID: PMC6798124 DOI: 10.1128/jvi.00559-19] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Accepted: 07/07/2019] [Indexed: 12/14/2022] Open
Abstract
Early interactions of influenza A virus (IAV) with respiratory epithelium might determine the outcome of infection. The study of global cellular innate immune responses often masks multiple aspects of the mechanisms by which populations of cells work as organized and heterogeneous systems to defeat virus infection, and how the virus counteracts these systems. In this study, we experimentally dissected the dynamics of IAV and human epithelial respiratory cell interaction during early infection at the single-cell level. We found that the number of viruses infecting a cell (multiplicity of infection [MOI]) influences the magnitude of virus antagonism of the host innate antiviral response. Infections performed at high MOIs resulted in increased viral gene expression per cell and stronger antagonist effect than infections at low MOIs. In addition, single-cell patterns of expression of interferons (IFN) and IFN-stimulated genes (ISGs) provided important insights into the contributions of the infected and bystander cells to the innate immune responses during infection. Specifically, the expression of multiple ISGs was lower in infected than in bystander cells. In contrast with other IFNs, IFN lambda 1 (IFNL1) showed a widespread pattern of expression, suggesting a different cell-to-cell propagation mechanism more reliant on paracrine signaling. Finally, we measured the dynamics of the antiviral response in primary human epithelial cells, which highlighted the importance of early innate immune responses at inhibiting virus spread.IMPORTANCE Influenza A virus (IAV) is a respiratory pathogen of high importance to public health. Annual epidemics of seasonal IAV infections in humans are a significant public health and economic burden. IAV also causes sporadic pandemics, which can have devastating effects. The main target cells for IAV replication are epithelial cells in the respiratory epithelium. The cellular innate immune responses induced in these cells upon infection are critical for defense against the virus, and therefore, it is important to understand the complex interactions between the virus and the host cells. In this study, we investigated the innate immune response to IAV in the respiratory epithelium at the single-cell level, providing a better understanding on how a population of epithelial cells functions as a complex system to orchestrate the response to virus infection and how the virus counteracts this system.
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Affiliation(s)
- Irene Ramos
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Gregory Smith
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Frederique Ruf-Zamojski
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Carles Martínez-Romero
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Miguel Fribourg
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Edwin A Carbajal
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- The Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Boris M Hartmann
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Venugopalan D Nair
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Nada Marjanovic
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Paula L Monteagudo
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Veronica A DeJesus
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Tinaye Mutetwa
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- The Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Michel Zamojski
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Gene S Tan
- Infectious Diseases, J. Craig Venter Institute, La Jolla, California, USA
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | | | - Elena Zaslavsky
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Randy A Albrecht
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- The Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Stuart C Sealfon
- Department of Neurology, Center for Advanced Research on Diagnostic Assays, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Adolfo García-Sastre
- Department of Microbiology, 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
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Ana Fernandez-Sesma
- Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- The Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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Zheng Z, Yang J, Jiang X, Liu Y, Zhang X, Li M, Zhang M, Fu M, Hu K, Wang H, Luo MH, Gong P, Hu Q. Tick-Borne Encephalitis Virus Nonstructural Protein NS5 Induces RANTES Expression Dependent on the RNA-Dependent RNA Polymerase Activity. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2018; 201:53-68. [PMID: 29760190 DOI: 10.4049/jimmunol.1701507] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 04/30/2018] [Indexed: 01/08/2023]
Abstract
Tick-borne encephalitis virus (TBEV) is one of the flaviviruses that targets the CNS and causes encephalitis in humans. The mechanism of TBEV that causes CNS destruction remains unclear. It has been reported that RANTES-mediated migration of human blood monocytes and T lymphocytes is specifically induced in the brain of mice infected with TBEV, which causes ensuing neuroinflammation and may contribute to brain destruction. However, the viral components responsible for RANTES induction and the underlying mechanisms remain to be fully addressed. In this study, we demonstrate that the NS5, but not other viral proteins of TBEV, induces RANTES production in human glioblastoma cell lines and primary astrocytes. TBEV NS5 appears to activate the IFN regulatory factor 3 (IRF-3) signaling pathway in a manner dependent on RIG-I/MDA5, which leads to the nuclear translocation of IRF-3 to bind with RANTES promoter. Further studies reveal that the activity of RNA-dependent RNA polymerase (RdRP) but not the RNA cap methyltransferase is critical for TBEV NS5-induced RANTES expression, and this is likely due to RdRP-mediated synthesis of dsRNA. Additional data indicate that the residues at K359, D361, and D664 of TBEV NS5 are critical for RdRP activity and RANTES induction. Of note, NS5s from other flaviviruses, including Japanese encephalitis virus, West Nile virus, Zika virus, and dengue virus, can also induce RANTES expression, suggesting the significance of NS5-induced RANTES expression in flavivirus pathogenesis. Our findings provide a foundation for further understanding how flaviviruses cause neuroinflammation and a potential viral target for intervention.
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Affiliation(s)
- Zifeng Zheng
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jieyu Yang
- University of Chinese Academy of Sciences, Beijing 100049, China
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Xuan Jiang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Yalan Liu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China;
| | - Xiaowei Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Mei Li
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Mudan Zhang
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Center, Guangzhou 510623, China; and
| | - Ming Fu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kai Hu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Hanzhong Wang
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Min-Hua Luo
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Peng Gong
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Qinxue Hu
- State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China;
- Institute for Infection and Immunity, St George's, University of London, London SW17 0RE, United Kingdom
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5
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Wang MM, Lu M, Zhang CL, Wu X, Chen JX, Lv WW, Sun T, Qiu H, Huang SH. Oxidative stress modulates the expression of toll‑like receptor 3 during respiratory syncytial virus infection in human lung epithelial A549 cells. Mol Med Rep 2018; 18:1867-1877. [PMID: 29845280 DOI: 10.3892/mmr.2018.9089] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2017] [Accepted: 05/11/2018] [Indexed: 11/05/2022] Open
Abstract
Toll‑like receptor 3 (TLR3) can react with double stranded RNA and is involved in the inflammatory response to respiratory syncytial virus (RSV) infection. Also, oxidative stress has been reported to be involved in RSV infection. However, the correlation between oxidative stress and TLR3 activation during RSV infection is unclear. Therefore, the present study investigated the association between TLR3 expression and oxidative stress modulation during RSV infection in A549 cells. For comparison, seven treatment groups were established, including RSV‑treated cells, N‑acetyl‑L‑cysteine (NAC)+RSV‑treated cells, oxidant hydrogen peroxide (H2O2)+RSV‑treated cells, normal cell control, inactivated RSV control, NAC control and H2O2 control. The mRNA expression changes of TLR3, interferon regulatory factor‑3 (IRF3), nuclear factor‑κB (NF‑κB) and superoxide dismutase 1 (SOD1) were measured using semi‑quantitative reverse transcription‑polymerase chain reaction, and the protein changes of TLR3 and phospho‑NF‑κB p65 were determined using western blot in A549 cells from the different treatment groups. The present study also evaluated the differences in hydroxyl free radical (·OH), nitric oxide (NO) and total SOD activity in the different treatment groups. The results demonstrated that RSV infection of A549 cells increased the levels of ·OH and NO, while decreasing the activity of total SOD. Pretreatment of A549 cells with H2O2 prior to RSV infection upregulated the mRNA and protein expression of TLR3 and NF‑κB, and downregulated the mRNA expression of IRF3 and SOD1, as well as the total SOD activity. When the infected cells were pretreated with NAC, the mRNA and protein expression of these genes were reversed. These variations in the TLR3‑mediated signaling pathway molecules suggested that oxidative stress may be a key regulator for TLR3 activation during RSV infection. RSV‑induced oxidative stress may potentially activate TLR3 and enhance TLR3‑mediated inflammation. These results may provide better understanding of the RSV‑induced inflammatory and immune pathways, and may also contribute to the drug development and prevention of human RSV diseases.
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Affiliation(s)
- Min-Min Wang
- Department of Microbiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Min Lu
- Department of Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Chuan-Long Zhang
- Department of Pediatrics, The People's Hospital of Lu'an City, Lu'an, Anhui 237005, P.R. China
| | - Xuan Wu
- Department of Microbiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Jing-Xian Chen
- Department of Microbiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Wei-Wei Lv
- Department of Microbiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Tao Sun
- Department of Microbiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Huan Qiu
- Department of Microbiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui 230032, P.R. China
| | - Sheng-Hai Huang
- Department of Microbiology, School of Basic Medical Sciences, Anhui Medical University, Hefei, Anhui 230032, P.R. China
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Airway Epithelial Orchestration of Innate Immune Function in Response to Virus Infection. A Focus on Asthma. Ann Am Thorac Soc 2017; 13 Suppl 1:S55-63. [PMID: 27027954 DOI: 10.1513/annalsats.201507-421mg] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Asthma is a very common respiratory condition with a worldwide prevalence predicted to increase. There are significant differences in airway epithelial responses in asthma that are of particular interest during exacerbations. Preventing exacerbations is a primary aim when treating asthma because they often necessitate unscheduled healthcare visits and hospitalizations and are a significant cause of morbidity and mortality. The most common cause of asthma exacerbations is a respiratory virus infection, of which the most likely type is rhinovirus infection. This article focuses on the role played by the epithelium in orchestrating the innate immune responses to respiratory virus infection. Recent studies show impaired bronchial epithelial cell innate antiviral immune responses, as well as augmentation of a pro-Th2 response characterized by the epithelial-derived cytokines IL-25 and IL-33, crucial in maintaining the Th2 cytokine response to virus infection in asthma. A better understanding of the mechanisms of these abnormal immune responses has the potential to lead to the development of novel therapeutic targets for virus-induced exacerbations. The aim of this article is to highlight current knowledge regarding the role of viruses and immune modulation in the asthmatic epithelium and to discuss exciting areas for future research and novel treatments.
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Abstract
Chronic airway diseases are a significant cause of morbidity and mortality worldwide, and their prevalence is predicted to increase in the future. Respiratory viruses are the most common cause of acute pulmonary infection, and there is clear evidence of their role in acute exacerbations of inflammatory airway diseases such as asthma and chronic obstructive pulmonary disease. Studies have reported impaired host responses to virus infection in these diseases, and a better understanding of the mechanisms of these abnormal immune responses has the potential to lead to the development of novel therapeutic targets for virus-induced exacerbations. The aim of this article is to review the current knowledge regarding the role of viruses and immune modulation in acute exacerbations of chronic pulmonary diseases and to discuss exciting areas for future research and novel treatments.
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Koizumi Y, Nagase H, Nakajima T, Kawamura M, Ohta K. Toll-like receptor 3 ligand specifically induced bronchial epithelial cell death in caspase dependent manner and functionally upregulated Fas expression. Allergol Int 2016; 65 Suppl:S30-7. [PMID: 27321649 DOI: 10.1016/j.alit.2016.05.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 05/10/2016] [Accepted: 05/11/2016] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND Viral infections are the most common cause of asthma exacerbation. Virally infected epithelial cells undergo apoptosis. Although in healthy conditions, apoptosis may have a host-defensive role in limiting virus spread, this process may have a detrimental effect on damaged epithelium in asthma. Toll-like receptors (TLRs) are the receptors for various pathogens, and viruses possess several components that can activate TLR3, TLR4, and TLR7/8. However, as it has not been determined as to which component is responsible for virus-induced epithelial cell apoptosis, we comprehensively analyzed the effects of all TLR ligands on apoptosis. METHODS BEAS-2B cells or primary cultured human bronchial epithelial cells (PBECs) were stimulated by TLR 2, 3, 4, 5, 7/8, and 9 ligands and cell death was analyzed by flow cytometry. Chemokine generations induced by these ligands were also analyzed. RESULTS The TLR3 ligand polyinosinic-polycytidylic acid (poly I:C) specifically induced chemokine generation and apoptosis, while other TLR ligands including those for TLR5, 7/8, and 9 had no effect. The response to poly I:C had two phases, which included rapid secretion of chemokines and subsequent apoptosis in a later phase. Poly I:C induced apoptosis in a caspase-dependent manner and functionally upregulated the expression of Fas. CONCLUSIONS Previous findings indicating that viruses induced caspase-dependent death and upregulated Fas expression were reproduced by poly I:C, suggesting the central role of dsRNA/TLR3 in virus-induced apoptosis. Since these processes may have detrimental effects on pre-existing epithelial damage, the dsRNA/TLR3 pathway may be potential novel treatment target for virus-induced exacerbation of asthma.
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9
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Matsukura S, Osakabe Y, Sekiguchi A, Inoue D, Kakiuchi Y, Funaki T, Yamazaki Y, Takayasu H, Tateno H, Kato E, Wakabayashi A, Hayashi M, Ishii G, Yamaguchi F, Tsuchiya Y, Kasahara K, Sagara H, Kokubu F. Overexpression of microRNA-155 suppresses chemokine expression induced by Interleukin-13 in BEAS-2B human bronchial epithelial cells. Allergol Int 2016; 65 Suppl:S17-23. [PMID: 27497617 DOI: 10.1016/j.alit.2016.04.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Revised: 04/23/2016] [Accepted: 04/30/2016] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND MicroRNAs are non-coding small RNAs that regulate expression of target genes by binding to 3' untranslated regions. In this study, we used bronchial epithelial cells to investigate in vitro the role of the microRNA miR-155 in the expression of chemokines associated with airway inflammation. miR-155 has previously been reported to regulate allergic inflammation. METHODS BEAS-2B bronchial epithelial cells were cultured and transfected with mimic or inhibitor oligonucleotides to overexpress or downregulate miR-155, as confirmed by real-time PCR. Cells were then stimulated with tumor necrosis factor-alpha, interleukin-13 (IL-13), and a double stranded RNA that binds Toll-like receptor 3. Expression and secretion of the chemokines CCL5, CCL11, CCL26, CXCL8, and CXCL10 were then quantified by real-time PCR and ELISA, respectively. Phosphorylation of signal transducer and activator of transcription 6 (STAT6), a target of the IL-13 receptor, was analyzed by ELISA. RESULTS miR-155 overexpression significantly suppressed IL-13-induced secretion of CCL11 and CCL26. These effects were specific, and were not observed for other chemokines, nor in cells with downregulated miR-155. miR-155 overexpression also suppressed CCL11 and CCL26 mRNA, but did not affect expression of the IL-13 receptor or phosphorylation of STAT6. CONCLUSIONS miR-155 specifically inhibits IL-13-induced expression of eosinophilic chemokines CCL11 and CCL26 in bronchial epithelial cells, even though the 3'-untranslated region of these genes do not contain a consensus binding site for miR-155.
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Affiliation(s)
- Satoshi Matsukura
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan.
| | - Yuki Osakabe
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Ayaka Sekiguchi
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Daisuke Inoue
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Yusuke Kakiuchi
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Toshitaka Funaki
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Yohei Yamazaki
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Hiromi Takayasu
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Hidetsugu Tateno
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Eisuke Kato
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Aya Wakabayashi
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Makoto Hayashi
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Gen Ishii
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan; Respiratory Disease Center, Showa University Northern Yokohama Hospital, Kanagawa, Japan
| | - Fumihiro Yamaguchi
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Yutaka Tsuchiya
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
| | - Keita Kasahara
- Respiratory Disease Center, Showa University Northern Yokohama Hospital, Kanagawa, Japan
| | - Hironori Sagara
- Department of Internal Medicine, Division of Allergy and Respiratory Medicine, Showa University School of Medicine, Tokyo, Japan
| | - Fumio Kokubu
- Department of Respiratory Internal Medicine, Showa University Fujigaoka Hospital, Kanagawa, Japan
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10
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Hewitt R, Farne H, Ritchie A, Luke E, Johnston SL, Mallia P. The role of viral infections in exacerbations of chronic obstructive pulmonary disease and asthma. Ther Adv Respir Dis 2016; 10:158-74. [PMID: 26611907 PMCID: PMC5933560 DOI: 10.1177/1753465815618113] [Citation(s) in RCA: 114] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Asthma and chronic obstructive pulmonary disease (COPD) are major causes of global morbidity and mortality worldwide. The clinical course of both asthma and COPD are punctuated by the occurrence of exacerbations, acute events characterized by increased symptoms and airflow obstruction. Exacerbations contribute most of the morbidity, mortality and excess healthcare costs associated with both asthma and COPD. COPD and asthma exacerbations are frequently associated with respiratory virus infections and this has led to an intense research focus into the mechanisms of virus-induced exacerbations over the past decade. Current therapies are effective in reducing chronic symptoms but are less effective in preventing exacerbations, particularly in COPD. Understanding the mechanisms of virus-induced exacerbation will lead to the development of new targeted therapies that can reduce the burden of virus-induced exacerbations. In this review we discuss current knowledge of virus-induced exacerbations of asthma and COPD with a particular focus on mechanisms, human studies, virus-bacteria interactions and therapeutic advances.
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Affiliation(s)
- Richard Hewitt
- National Heart and Lung Institute, Imperial College London, UK
| | - Hugo Farne
- National Heart and Lung Institute, Imperial College London, UK
| | - Andrew Ritchie
- National Heart and Lung Institute, Imperial College London, UK
| | - Emma Luke
- Imperial Healthcare NHS Trust, London, UK
| | | | - Patrick Mallia
- Faculty of Medicine, National Heart and Lung Institute, Imperial College London, London SW7 2AZ, UK
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11
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Lever AR, Park H, Mulhern TJ, Jackson GR, Comolli JC, Borenstein JT, Hayden PJ, Prantil-Baun R. Comprehensive evaluation of poly(I:C) induced inflammatory response in an airway epithelial model. Physiol Rep 2015; 3:3/4/e12334. [PMID: 25847914 PMCID: PMC4425952 DOI: 10.14814/phy2.12334] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Respiratory viruses invade the upper airway of the lung, triggering a potent immune response that often exacerbates preexisting conditions such as asthma and COPD. Poly(I:C) is a synthetic analog of viral dsRNA that induces the characteristic inflammatory response associated with viral infection, such as loss of epithelial integrity, and increased production of mucus and inflammatory cytokines. Here, we explore the mechanistic responses to poly(I:C) in a well-defined primary normal human bronchial epithelial (NHBE) model that recapitulates in vivo functions and responses. We developed functional and quantifiable methods to evaluate the physiology of our model in both healthy and inflamed states. Through gene and protein expression, we validated the differentiation state and population of essential cell subtypes (i.e., ciliated, goblet, club, and basal cells) as compared to the human lung. Assays for total mucus production, cytokine secretion, and barrier function were used to evaluate in vitro physiology and response to viral insult. Cells were treated apically with poly(I:C) and evaluated 48 h after induction. Results revealed a dose-dependent increase in goblet cell differentiation, as well as, an increase in mucus production relative to controls. There was also a dose-dependent increase in secretion of IL-6, IL-8, TNF-α, and RANTES. Epithelial barrier function, as measured by TEER, was maintained at 1501 ± 355 Ω*cm² postdifferentiation, but dropped significantly when challenged with poly(I:C). This study provides first steps toward a well-characterized model with defined functional methods for understanding dsRNA stimulated inflammatory responses in a physiologically relevant manner.
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Affiliation(s)
- Amanda R Lever
- Charles Stark Draper Laboratory, Cambridge, Massachusetts
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12
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Jang HY, Jeon R, Kang KW, Song MY, Lim JM, Lee E, Ryu JH, Lee SM, Park BH. SPA0355 suppresses T-cell responses and reduces airway inflammation in mice. Eur J Pharmacol 2014; 745:19-28. [PMID: 25446921 DOI: 10.1016/j.ejphar.2014.08.038] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 08/25/2014] [Accepted: 08/25/2014] [Indexed: 11/17/2022]
Abstract
In recent studies, SPA0355, a thiourea analog, has been demonstrated to possess strong anti-inflammatory activity. However, the mechanisms underlying the effects of SPA0355 on immune-mediated diseases have not been fully defined. The present study was designed to investigate the immunological and molecular mechanisms by which SPA0355 modulates cluster of differentiation of (CD4)(+) T-cell-mediated immune responses in allergic airway inflammation. In vitro studies have shown that SPA0355 suppresses CD4(+) T-cell activation, proliferation, and differentiation via modulation of T-cell receptor (TCR) signal transduction and cytokine-induced Janus kinase/signal transducer and activator of transcription (JAK/STAT) signaling. Next, we investigated the efficacy of SPA0355 in ovalbumin (OVA)-induced allergic airway inflammation. Intraperitoneal administration of SPA0355 inhibited inflammatory cell recruitment into the airways as well as the production of Th2 cytokines in bronchoalveolar fluid and suppressed OVA-induced IgE production in serum. Additionally, SPA0355 suppressed mucin production and smooth muscle hypertrophy and prevented the development of airway hyperresponsiveness. Given that allergic airway inflammation is mainly driven by Th2 cell responses, it is highly possible that the defects in CD4(+) T-cell activation and Th2 cell differentiation in the draining lymph nodes and suppressed NF-κB activation in the lungs of SPA0355-treated mice illustrate an immunological mechanism of the preventive effect of SPA0355 on the aforementioned asthmatic characteristics. Collectively, our results suggest that SPA0355 directly modulates Th1 and Th2 responses through the suppression of multiple signaling pathways triggered by TCR or cytokine receptor stimulation, and that SPA0355 has protective effects in a murine model of allergic airway inflammation.
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Affiliation(s)
- Hyun-Young Jang
- Departments of Biochemistry National University Medical School, Jeonju, Jeonbuk 561-756, Republic of Korea
| | - Raok Jeon
- College of Pharmacy, Sookmyung Women׳s University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742, Republic of Korea
| | - Kyung-Won Kang
- Division of Biotechnology, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan, Jeonbuk 570-752, Republic of Korea
| | - Mi-Young Song
- Departments of Biochemistry National University Medical School, Jeonju, Jeonbuk 561-756, Republic of Korea
| | - Jung Min Lim
- Departments of Anatomy, Chonbuk National University Medical School, Jeonju, Jeonbuk 561-756, Republic of Korea
| | - Eun Lee
- College of Pharmacy, Sookmyung Women׳s University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742, Republic of Korea
| | - Jae-Ha Ryu
- College of Pharmacy, Sookmyung Women׳s University, 52 Hyochangwon-gil, Yongsan-gu, Seoul 140-742, Republic of Korea
| | - Sang-Myeong Lee
- Division of Biotechnology, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan, Jeonbuk 570-752, Republic of Korea.
| | - Byung-Hyun Park
- Departments of Biochemistry National University Medical School, Jeonju, Jeonbuk 561-756, Republic of Korea.
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Nousiainen L, Sillanpää M, Jiang M, Thompson J, Taipale J, Julkunen I. Human kinome analysis reveals novel kinases contributing to virus infection and retinoic-acid inducible gene I-induced type I and type III IFN gene expression. Innate Immun 2013; 19:516-30. [PMID: 23405030 DOI: 10.1177/1753425912473345] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023] Open
Abstract
Activation of host innate antiviral responses are mediated by retinoic-acid inducible gene I (RIG-I)-like receptors, RIG-I and melanoma differentiation-associated gene 5, and TLRs 3, 7, 8 and 9, recognising different types of viral nucleic acids. The major components of the RIG-I- and TLR pathways have putatively been identified, but previously unrecognised kinases may contribute to virus infection-induced activation of the IFN response. Here, we screened a human kinase cDNA library, termed the kinome, using an IFN-λ1 promoter-driven luciferase reporter assay in HEK293 cells during Sendai virus infection. Of the 568 kinases analysed, nearly 50 enhanced IFN-λ1 gene expression at least twofold in response to Sendai virus infection. The best activators were FYN (FYN oncogene related to SRC, FGR, YES), serine/threonine kinase 24, activin A receptor type 1 and SRPK1 (SFRS protein kinase 1). These kinases enhanced RIG-I-dependent IFN-λ1 promoter activation via IFN-stimulated response and NF-κB elements, as confirmed using mutant IFN-λ1 promoter constructs. FYN and SRPK1 enhanced IFN-λ1 and CXCL10 protein production via the RIG-I pathway, and stimulated RIG-I and MyD88-dependent phosphorylation of IRF3 and IRF7 transcription factors, respectively. We conclude that several previously unrecognised kinases, particularly FYN and SRPK1, positively regulate IFN-λ1 and similarly regulated cytokine and chemokine genes during viral infection.
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Affiliation(s)
- Laura Nousiainen
- 1Department of Infectious Disease Surveillance and Control, National Institute for Health and Welfare (THL), Helsinki, Finland
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Brandelius A, Mahmutovic Persson I, Calvén J, Bjermer L, Persson CGA, Andersson M, Uller L. Selective inhibition by simvastatin of IRF3 phosphorylation and TSLP production in dsRNA-challenged bronchial epithelial cells from COPD donors. Br J Pharmacol 2013; 168:363-74. [PMID: 22881993 DOI: 10.1111/j.1476-5381.2012.02131.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2012] [Revised: 07/11/2012] [Accepted: 07/30/2012] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND AND PURPOSE Statin treatment may ameliorate viral infection-induced exacerbations of chronic obstructive pulmonary disease (COPD), which exhibit Th2-type bronchial inflammation. Thymic stromal lymphopoietin (TSLP), a hub cytokine switching on Th2 inflammation, is overproduced in viral and dsRNA-stimulated bronchial epithelial cells from COPD donors. Hence, TSLP may be causally involved in exacerbations. This study tests the hypothesis that simvastatin inhibits dsRNA-induced TSLP. EXPERIMENTAL APPROACH Epithelial cells, obtained by bronchoscopy from COPD (n = 7) and smoker control (n = 8) donors, were grown and stimulated with a viral infection and danger signal surrogate, dsRNA (10 μg·mL(-1) ). Cells were treated with simvastatin (0.2-5 μg·mL(-1) ), with or without mevalonate (13-26 μg·mL(-1) ), or dexamethasone (1 μg·mL(-1) ) before dsRNA. Cytokine expression and production, and transcription factor (IRF3 and NF-κB) activation were determined. KEY RESULTS dsRNA induced TSLP, TNF-α, CXCL8 and IFN-β. TSLP was overproduced in dsRNA-exposed COPD cells compared with control. Simvastatin, but not dexamethasone, concentration-dependently inhibited dsRNA-induced TSLP. Unexpectedly, simvastatin acted independently of mevalonate and did not affect dsRNA-induced NF-κB activation nor did it reduce production of TNF-α and CXCL8. Instead, simvastatin inhibited dsRNA-induced IRF3 phosphorylation and generation of IFN-β. CONCLUSIONS AND IMPLICATIONS Independent of mevalonate and NF-κB, previously acknowledged anti-inflammatory mechanisms of pleiotropic statins, simvastatin selectively inhibited dsRNA-induced IRF3 activation and production of TSLP and IFN-β in COPD epithelium. These data provide novel insight into epithelial generation of TSLP and suggest paths to be exploited in drug discovery aimed at inhibiting TSLP-induced pulmonary immunopathology.
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15
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Matsukura S, Kurokawa M, Homma T, Watanabe S, Suzuki S, Ieki K, Takeuchi H, Notomi K, Schleimer RP, Kawaguchi M, Kokubu F. Basic research on virus-induced asthma exacerbation: inhibition of inflammatory chemokine expression by fluticasone propionate. Int Arch Allergy Immunol 2013; 161 Suppl 2:84-92. [PMID: 23711858 DOI: 10.1159/000350455] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Viral infection can exacerbate asthma by inducing the accumulation of inflammatory cells in the airway. We have previously reported that double-stranded RNA (dsRNA), a viral product and ligand of the Toll-like receptor-3 (TLR3), activates the transcription factors NF-κB and IRF-3 and upregulates the expression of inflammatory chemokines in airway epithelial cells. Here, we examined the effects of the glucocorticoid fluticasone propionate (FP) on the expression of the inflammatory chemokines CCL5, CXCL8 and CXCL10. METHODS The airway epithelial cell line BEAS-2B was used for this study. Expression of CCL5, CXCL8 and CXCL10 mRNA and protein was quantified by real-time PCR and ELISA assay, respectively. To examine the association of FP with the physiology of chemokine production, we included several methods. Nuclear translocation of transcription factors was determined by performing Western blot analysis. Histone deacetylase (HDAC) activity in nuclear extracts was measured using a colorimetric assay. Stability of the chemokine mRNAs was examined in cells incubated with actinomycin D. The activities of the CCL5 promoter and the transcription factors NF-κB and IRF-3 were assessed using luciferase reporter assays. RESULTS Treatment of BEAS-2B cells with FP significantly and dose-dependently (10(-9) to 10(-6)M) inhibited dsRNA-induced expression of CCL5, CXCL8 and CXCL10 protein and mRNA, but did not affect mRNA stability. FP also significantly inhibited dsRNA-stimulated CCL5 promoter activity. However, FP had no effect on the activity of HDAC or the nuclear translocation of NF-κB and IRF-3. CONCLUSIONS FP inhibits the dsRNA-stimulated expression of inflammatory chemokines in airway epithelial cells. FP may act by inhibiting chemokine transcription through an as yet unidentified mechanism.
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Affiliation(s)
- Satoshi Matsukura
- Department of Respiratory and Allergy Internal Medicine, Showa University School of Medicine, Tokyo, Japan.
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16
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Radwan M, Gavriilidis C, Robinson JH, Davidson R, Clark IM, Rowan AD, Young DA. Matrix metalloproteinase 13 expression in response to double-stranded RNA in human chondrocytes. ARTHRITIS AND RHEUMATISM 2013; 65:1290-301. [PMID: 23334990 DOI: 10.1002/art.37868] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2012] [Accepted: 01/08/2013] [Indexed: 01/10/2023]
Abstract
OBJECTIVE To investigate the mechanism of matrix metalloproteinase 13 (MMP-13) expression in chondrocytes via pattern-recognition receptors (PRRs) for double-stranded RNA (dsRNA). METHODS Differential expression of PRRs was determined by real-time reverse transcription-polymerase chain reaction (RT-PCR) of RNA from patients with osteoarthritis (OA) and patients with femoral neck fracture (as normal control). Isolated human articular chondrocytes and the chondrosarcoma cell line SW-1353 were activated with poly(I-C) of different molecular weights as a dsRNA mimic, and changes in gene and protein expression were monitored by real-time RT-PCR and immunoblotting, respectively. RESULTS The dsRNA signaling moieties Toll-like receptor 3 (TLR-3), retinoic acid-inducible gene 1 (RIG-1), and nucleotide-binding oligomerization domain-like receptor X1 were all differentially expressed in OA cartilage compared to normal cartilage, as determined by gene expression screening. Depletion of the dsRNA-sensing receptors TLR-3, RIG-1, or melanoma differentiation-associated gene 5 (MDA-5) suppressed the induction of MMP13 messenger RNA (mRNA) expression by poly(I-C), regardless of its mode of delivery. In addition, depletion of the downstream transcription factor interferon regulatory factor 3 resulted in reduced induction of MMP13 mRNA expression by poly(I-C). CONCLUSION Signaling by dsRNA in chondrocytes requires a range of PRRs, including TLR-3, RIG-1, and MDA-5, for the full-induction of MMP13, thus providing tight regulation of a gene critical for maintenance of cartilage integrity. Our data add to the understanding of MMP13 regulation, which is essential before such mechanisms can be exploited to alleviate the cartilage destruction associated with OA.
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MESH Headings
- Cartilage, Articular/cytology
- Cell Line, Tumor
- Chondrocytes/drug effects
- Chondrocytes/enzymology
- DEAD Box Protein 58
- DEAD-box RNA Helicases/genetics
- DEAD-box RNA Helicases/metabolism
- Femoral Neck Fractures/genetics
- Femoral Neck Fractures/metabolism
- Gene Expression Regulation/genetics
- Humans
- Interferon-Induced Helicase, IFIH1
- Interleukin-1alpha/pharmacology
- Matrix Metalloproteinase 13/genetics
- Matrix Metalloproteinase 13/metabolism
- Necrosis
- Nod2 Signaling Adaptor Protein/genetics
- Nod2 Signaling Adaptor Protein/metabolism
- Osteoarthritis/genetics
- Osteoarthritis/metabolism
- Poly I-C/pharmacology
- RNA, Double-Stranded/pharmacology
- RNA, Messenger/metabolism
- RNA, Ribosomal, 18S/genetics
- RNA, Small Interfering/administration & dosage
- RNA, Small Interfering/genetics
- Receptors, Immunologic
- Receptors, Pattern Recognition/drug effects
- Receptors, Pattern Recognition/genetics
- Receptors, Pattern Recognition/metabolism
- Recombinant Proteins
- Toll-Like Receptor 2/genetics
- Toll-Like Receptor 2/metabolism
- Toll-Like Receptor 3/genetics
- Toll-Like Receptor 3/metabolism
- Transfection/methods
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TLR3 activation evokes IL-6 secretion, autocrine regulation of Stat3 signaling and TLR2 expression in human bronchial epithelial cells. J Cell Commun Signal 2012; 7:109-18. [PMID: 23232980 DOI: 10.1007/s12079-012-0185-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Accepted: 11/27/2012] [Indexed: 12/24/2022] Open
Abstract
Human bronchial epithelial cells exposed to synthetic double-stranded RNA (poly I:C) exhibited increased IL-6 and RANTES secretion and TLR2 expression that was inhibited following TLR3 silencing. Increased NF-κB and Stat3 phosphorylation were detected after poly I:C exposure and pretreatment with neutralizing antibody targeting IL-6 receptor α (IL-6Rα -nAb) or blocking Jak2 and Stat3 activity inhibited Stat3 phosphorylation. TLR2 up-regulation by poly I:C was also reduced by IL-6Rα-nAb and inhibitors of Jak2, Stat3 and NF-κB phosphorylation, whereas RANTES secretion was unaffected, but abolished following NF-κB inhibition. Treatment with exogenous IL-6 failed to increase TLR2. These findings demonstrate that TLR3 activation differentially regulates TLR expression through autocrine signaling involving IL-6 secretion, IL-6Rα activation and subsequent phosphorylation of Stat3. The results also indicate that NF-κB and Stat3 are required for TLR3-dependent up-regulation of TLR2 and that its delayed expression was due to a requirement for IL-6-dependent Stat3 activation.
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18
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Singanayagam A, Joshi PV, Mallia P, Johnston SL. Viruses exacerbating chronic pulmonary disease: the role of immune modulation. BMC Med 2012; 10:27. [PMID: 22420941 PMCID: PMC3353868 DOI: 10.1186/1741-7015-10-27] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Accepted: 03/15/2012] [Indexed: 12/30/2022] Open
Abstract
Chronic pulmonary diseases are a major cause of morbidity and mortality and their impact is expected to increase in the future. Respiratory viruses are the most common cause of acute respiratory infections and it is increasingly recognized that respiratory viruses are a major cause of acute exacerbations of chronic pulmonary diseases such as asthma, chronic obstructive pulmonary disease and cystic fibrosis. There is now increasing evidence that the host response to virus infection is dysregulated in these diseases and a better understanding of the mechanisms of abnormal immune responses has the potential to lead to the development of new therapies for virus-induced exacerbations. The aim of this article is to review the current knowledge regarding the role of viruses and immune modulation in chronic pulmonary diseases and discuss avenues for future research and therapeutic implications.
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Affiliation(s)
- Aran Singanayagam
- National Heart and Lung Institute, Imperial College London, Norfolk Place, London W2 1PG, UK
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19
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Wang Y, Luo R, Fang L, Wang D, Bi J, Chen H, Xiao S. Porcine reproductive and respiratory syndrome virus (PRRSV) infection activates chemokine RANTES in MARC-145 cells. Mol Immunol 2011; 48:586-91. [DOI: 10.1016/j.molimm.2010.10.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2010] [Revised: 10/06/2010] [Accepted: 10/25/2010] [Indexed: 12/01/2022]
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20
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Homma T, Matsukura S, Hirose T, Ohnishi T, Kimura T, Kurokawa M, Ieki K, Odaka M, Suzuki S, Watanabe S, Sato M, Kawaguchi M, Schleimer RP, Adachi M. Cooperative activation of CCL5 expression by TLR3 and tumor necrosis factor-alpha or interferon-gamma through nuclear factor-kappaB or STAT-1 in airway epithelial cells. Int Arch Allergy Immunol 2010; 152 Suppl 1:9-17. [PMID: 20523058 DOI: 10.1159/000312120] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND CCL5/RANTES contributes to prolonged eosinophilic inflammation and asthma exacerbation after a viral infection. We studied the mechanism of CCL5 expression using viral product double-stranded RNA (dsRNA), a ligand of Toll-like receptor 3 (TLR3), and inflammatory cytokines in airway epithelial cells. METHODS The airway epithelial cell line BEAS-2B was used in our in vitro study, and the levels of CCL5 mRNA and CCL5 protein expression were determined using real-time PCR and ELISA. The activity of the CCL5 promoter region and nuclear factor (NF)-kappaB was assessed by dual luciferase assay using specific luciferase reporter plasmids. We used actinomycin D to assess the stability of mRNA. Phosphorylation of signal transducer and activator of transcription 1 (STAT-1) was analyzed by Western blot. RESULTS Synthetic dsRNA up-regulated the expression of CCL5 mRNA and CCL5 protein. Adding TNF-alpha or IFN-gamma to dsRNA further increased the expression of CCL5. The combination of TNF-alpha and dsRNA cooperatively activated the CCL5 promoter region and the NF-kappaB-specific reporter. IFN-gamma did not activate these reporters. However, it increased the stability of CCL5 mRNA induced by dsRNA. IFN-gamma phosphorylated STAT-1, but dsRNA did not. The effects of IFN-gamma were not evident in the cells transfected with short interfering RNA for STAT-1. CONCLUSIONS Cross-talk between TLR3 signaling and inflammatory cytokines regulates the expression of CCL5 in airway epithelial cells. In this mechanism, TNF-alpha may activate NF-kappaB, in cooperation with TLR3 signaling. IFN-gamma may stabilize CCL5 mRNA up-regulated by TLR3. This mechanism may depend on STAT-1.
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Affiliation(s)
- Tetsuya Homma
- Division of Respiratory Medicine and Allergy, Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan
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21
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Cridge TJ, Horowitz KM, Marinucci MN, Rose KM, Wells M, Werner MT, Kurt RA. Functional and Molecular Alterations in T Cells Induced by CCL5. Immunol Invest 2009; 35:115-32. [PMID: 16531333 DOI: 10.1080/08820130500514365] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
To delineate whether, and the extent to which, CCL5 could impact T cell function we examined cytokine production and proliferative ability following CCL5 treatment in vitro. We report a decreased ability of splenic T cells to produce IFN-? and TNF-a as well as proliferate in response to crosslinking with antibody to CD3 after 72, but not 24 hours of CCL5 exposure. To identify a mechanism by which CCL5 modulated T cell function, we examined T cell receptor translocation and lipid raft clustering. After exposure to CCL5, T cells were less efficient at translocating the TCR and clustering lipid rafts. Since TCR translocation and lipid raft clustering are required for creation of an immunological synapse, these data suggest that extended exposure to CCL5 may impact T cell effector function by modulating the ability to create a functional immunological synapse.
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Affiliation(s)
- T J Cridge
- Department of Biology, Lafayette College, Easton, Pennsylvania 18042, USA
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22
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Stowell NC, Seideman J, Raymond HA, Smalley KA, Lamb RJ, Egenolf DD, Bugelski PJ, Murray LA, Marsters PA, Bunting RA, Flavell RA, Alexopoulou L, San Mateo LR, Griswold DE, Sarisky RT, Mbow ML, Das AM. Long-term activation of TLR3 by poly(I:C) induces inflammation and impairs lung function in mice. Respir Res 2009; 10:43. [PMID: 19486528 PMCID: PMC2694181 DOI: 10.1186/1465-9921-10-43] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Accepted: 06/01/2009] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND The immune mechanisms associated with infection-induced disease exacerbations in asthma and COPD are not fully understood. Toll-like receptor (TLR) 3 has an important role in recognition of double-stranded viral RNA, which leads to the production of various inflammatory mediators. Thus, an understanding of TLR3 activation should provide insight into the mechanisms underlying virus-induced exacerbations of pulmonary diseases. METHODS TLR3 knock-out (KO) mice and C57B6 (WT) mice were intranasally administered repeated doses of the synthetic double stranded RNA analog poly(I:C). RESULTS There was a significant increase in total cells, especially neutrophils, in BALF samples from poly(I:C)-treated mice. In addition, IL-6, CXCL10, JE, KC, mGCSF, CCL3, CCL5, and TNFalpha were up regulated. Histological analyses of the lungs revealed a cellular infiltrate in the interstitium and epithelial cell hypertrophy in small bronchioles. Associated with the pro-inflammatory effects of poly(I:C), the mice exhibited significant impairment of lung function both at baseline and in response to methacholine challenge as measured by whole body plethysmography and an invasive measure of airway resistance. Importantly, TLR3 KO mice were protected from poly(I:C)-induced changes in lung function at baseline, which correlated with milder inflammation in the lung, and significantly reduced epithelial cell hypertrophy. CONCLUSION These findings demonstrate that TLR3 activation by poly(I:C) modulates the local inflammatory response in the lung and suggest a critical role of TLR3 activation in driving lung function impairment. Thus, TLR3 activation may be one mechanism through which viral infections contribute toward exacerbation of respiratory disease.
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Affiliation(s)
- Nicole C Stowell
- Discovery Research, Centocor Research & Development, Inc, Radnor, Pennsylvania, USA.
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23
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Fosfomycin suppresses chemokine induction in airway epithelial cells infected with respiratory syncytial virus. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2009; 16:859-65. [PMID: 19369476 DOI: 10.1128/cvi.00033-09] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Respiratory syncytial virus (RSV) infects airway epithelial cells, causing bronchiolitis and pneumonia. Inflammation is mediated by various cytokines secreted from RSV-infected airway epithelial cells, and it promotes the pathogenesis of RSV-related diseases. Fosfomycin (FOF) is approved as a treatment for various bacterial infectious diseases, including respiratory infectious diseases, in Japan. FOF is suggested to exhibit immunomodulatory effects on lipopolysaccharide-stimulated monocytes and T lymphocytes, in addition to its antimicrobial activity. We investigated the effect of FOF on the cytokine production of an airway epithelial cell line, A549, infected with RSV. RSV-induced cytokines, such as regulated on activation, normal T-cell expressed and secreted (RANTES), interleukin-8 (IL-8), and IL-6, in infected A549 cells. We found that FOF decreased the levels of RSV-induced RANTES and IL-8 but not the level of RSV-induced IL-6. The RANTES promoter was activated by RSV infection. Site-directed mutagenesis analysis of the RANTES promoter showed that NF-kappaB-binding motifs had a critical role in RSV-induced RANTES promoter activity. A luciferase reporter gene assay and a DNA-binding assay indicated that FOF suppressed the NF-kappaB activity induced by RSV infection. These results demonstrate that FOF treatment suppresses the RSV-induced transcription of the chemokines RANTES and IL-8 in airway epithelial cells.
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Tadaki H, Arakawa H, Mizuno T, Suzuki T, Takeyama K, Mochizuki H, Tokuyama K, Yokota S, Morikawa A. Double-stranded RNA and TGF-alpha promote MUC5AC induction in respiratory cells. THE JOURNAL OF IMMUNOLOGY 2009; 182:293-300. [PMID: 19109160 DOI: 10.4049/jimmunol.182.1.293] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Viral infection is a major trigger for exacerbation of asthma and induces overproduction of mucins. We investigated whether dsRNA could amplify the induction of mucin by TGF-alpha in human bronchial epithelial cells, as well as the molecular mechanisms regulating MUC5AC expression. Human pulmonary mucoepidermoid carcinoma (NCI-H292) cells and normal human bronchial epithelial cells were exposed to polyinosinic-cytidyric acid (poly(I:C)) and TGF-alpha. Then, MUC5AC protein production, mRNA expression, and promoter activity were evaluated. Cells were pretreated with a selective inhibitor of ERK, and phosphorylation of ERK was examined by Western blotting. Furthermore, the expression of MAPK phosphatase 3 (MKP3) mRNA was evaluated and the effect of MKP3 overexpression was assessed. Poly(I:C) synergistically increased MUC5AC induction by TGF-alpha in both NCI-H292 and normal human bronchial epithelial cells. This increase was dependent on MUC5AC gene transcription. A MEK1/2 inhibitor (U0126) significantly inhibited MUC5AC production. Phosphorylation of ERK was enhanced by poly(I:C). TGF-alpha stimulation up-regulated MKP3 mRNA expression, while costimulation with poly(I:C) inhibited this up-regulation dose-dependently. Enhanced expression of MUC5AC mRNA by poly(I:C) in wild-type cells was completely suppressed in cells transfected with the MKP3 expression vector. dsRNA can synergistically amplify the induction of MUC5AC mucin by TGF-alpha. This synergistic effect on MUC5AC production may be due to enhanced activation of ERK through inhibition of MKP3 by poly(I:C).
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Affiliation(s)
- Hiromi Tadaki
- Department of Pediatrics and Developmental Medicine, Gunma University Graduate School of Medicine, Gunma, Japan
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Kumar D, Hosse J, von Toerne C, Noessner E, Nelson PJ. JNK MAPK Pathway Regulates Constitutive Transcription of CCL5 by Human NK Cells through SP1. THE JOURNAL OF IMMUNOLOGY 2009; 182:1011-20. [DOI: 10.4049/jimmunol.182.2.1011] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Christopher ME, Wong JP. Broad-spectrum drugs against viral agents. Int J Mol Sci 2008; 9:1561-1594. [PMID: 19325820 PMCID: PMC2635754 DOI: 10.3390/ijms9091561] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2008] [Revised: 08/21/2008] [Accepted: 08/29/2008] [Indexed: 01/06/2023] Open
Abstract
Development of antivirals has focused primarily on vaccines and on treatments for specific viral agents. Although effective, these approaches may be limited in situations where the etiologic agent is unknown or when the target virus has undergone mutation, recombination or reassortment. Augmentation of the innate immune response may be an effective alternative for disease amelioration. Nonspecific, broad-spectrum immune responses can be induced by double-stranded (ds)RNAs such as poly (ICLC), or oligonucleotides (ODNs) containing unmethylated deocycytidyl-deoxyguanosinyl (CpG) motifs. These may offer protection against various bacterial and viral pathogens regardless of their genetic makeup, zoonotic origin or drug resistance.
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Duffy KE, Lamb RJ, San Mateo LR, Jordan JL, Canziani G, Brigham-Burke M, Korteweg J, Cunningham M, Beck HS, Carton J, Giles-Komar J, Duchala C, Sarisky RT, Mbow ML. Down modulation of human TLR3 function by a monoclonal antibody. Cell Immunol 2007; 248:103-14. [PMID: 18048020 DOI: 10.1016/j.cellimm.2007.10.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2007] [Revised: 10/05/2007] [Accepted: 10/09/2007] [Indexed: 12/22/2022]
Abstract
Toll-like receptors are a family of pattern-recognition receptors that contribute to the innate immune response. Toll-like receptor 3 (TLR3) signals in response to foreign, endogenous and synthetic ligands including viral dsRNA, bacterial RNA, mitochondrial RNA, endogenous necrotic cell mRNA and the synthetic dsRNA analog, poly(I:C). We have generated a monoclonal antibody (mAb CNTO2424) that recognizes the extracellular domain (ECD) of human TLR3 in a conformation-dependent manner. CNTO2424 down-regulates poly(I:C)-induced production of IL-6, IL-8, MCP-1, RANTES, and IP-10 in human lung epithelial cells. In addition, mAb CNTO2424 was able to interfere with the known TLR3-dependent signaling pathways, namely NF-kappaB, IRF-3/ISRE, and p38 MAPK. The generation of this neutralizing anti-TLR3 mAb provides a unique tool to better understand TLR3 signaling and potential cross-talk between TLR3 and other molecules.
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Affiliation(s)
- Karen E Duffy
- Discovery Research, Centocor Research and Development, Inc., Malvern, PA 19355, USA.
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Odaka M, Matsukura S, Kuga H, Kokubu F, Kasama T, Kurokawa M, Kawaguchi M, Ieki K, Suzuki S, Watanabe S, Homma T, Takeuchi H, Nohtomi K, Schleimer RP, Adachi M. Differential regulation of chemokine expression by Th1 and Th2 cytokines and mechanisms of eotaxin/CCL-11 expression in human airway smooth muscle cells. Int Arch Allergy Immunol 2007; 143 Suppl 1:84-8. [PMID: 17541284 PMCID: PMC2121189 DOI: 10.1159/000101412] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Airway smooth muscle (ASM) cells may contribute to the pathogenesis of asthma including airway inflammation and remodeling. We focused our study on the regulation of chemokine expression by cytokines and analyzed the mechanisms of eotaxin/CCL-11 expression in ASM cells. METHODS Human ASM cells were cultured in vitro and treated with IL-4, interferon-gamma (IFNgamma), and tumor necrosis factor-alpha (TNFalpha). Secretion of chemokines into the culture medium was analyzed by ELISA. Expression of eotaxin mRNA was analyzed by reverse transcription-polymerase chain reaction (RT-PCR). Binding of transcription factor signal transducer activator of transcription (STAT) 6 to the eotaxin promoter-derived DNA was analyzed by pull-down Western blot. To assess transcriptional regulation of eotaxin, cells were transfected with eotaxin promoter-luciferase reporter plasmids, and activity was determined by dual luciferase assay. RESULTS The Th2 cytokine IL-4 preferentially stimulated the expression of the CC chemokine receptor (CCR) 3-ligand chemokines eotaxin, eotaxin-3, and MCP-4. The Th1 cytokine IFNgamma stimulated the expression of chemokines IP-10 and RANTES. IL-4 stimulated nuclear translocation of signal transducer activator of transcription 6 (STAT6) and its binding to the eotaxin promoter region. IL-4 activated the eotaxin promoter and its activity was inhibited by mutation of the binding site for STAT6 in the promoter. CONCLUSIONS The Th2 cytokine IL-4 preferentially stimulated the expression of CCR3 ligand chemokines including eotaxin in ASM cells. The transcription factor STAT6 may play a pivotal role in the activation of eotaxin transcription in response to IL-4.
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MESH Headings
- Active Transport, Cell Nucleus/drug effects
- Chemokine CCL11
- Chemokine CCL26
- Chemokine CCL5/biosynthesis
- Chemokine CCL5/genetics
- Chemokine CCL5/metabolism
- Chemokine CXCL10
- Chemokines, CC/biosynthesis
- Chemokines, CC/genetics
- Chemokines, CC/metabolism
- Chemokines, CXC/biosynthesis
- Chemokines, CXC/genetics
- Chemokines, CXC/metabolism
- Drug Synergism
- Enzyme-Linked Immunosorbent Assay
- Gene Expression Regulation/drug effects
- Humans
- Interferon-gamma/pharmacology
- Interferon-gamma/physiology
- Interleukin-4/pharmacology
- Interleukin-4/physiology
- Monocyte Chemoattractant Proteins/biosynthesis
- Monocyte Chemoattractant Proteins/genetics
- Monocyte Chemoattractant Proteins/metabolism
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Promoter Regions, Genetic
- Protein Binding/drug effects
- RNA, Messenger
- Recombinant Proteins/pharmacology
- Respiratory System/cytology
- STAT6 Transcription Factor/physiology
- Th1 Cells/physiology
- Th2 Cells/physiology
- Tumor Necrosis Factor-alpha/pharmacology
- Tumor Necrosis Factor-alpha/physiology
- Up-Regulation/drug effects
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Affiliation(s)
- Miho Odaka
- First Department of Internal Medicine, Showa University School of Medicine, Shinagawa, Tokyo, Japan.
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Matsukura S, Kokubu F, Kurokawa M, Kawaguchi M, Ieki K, Kuga H, Odaka M, Suzuki S, Watanabe S, Homma T, Takeuchi H, Nohtomi K, Adachi M. Role of RIG-I, MDA-5, and PKR on the expression of inflammatory chemokines induced by synthetic dsRNA in airway epithelial cells. Int Arch Allergy Immunol 2007; 143 Suppl 1:80-3. [PMID: 17541283 DOI: 10.1159/000101411] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND We hypothesized that synthetic double-stranded (ds)RNA may mimic viral infection and reported that dsRNA stimulates expression of inflammatory chemokines through a receptor of dsRNA Toll-like receptor (TLR) 3 in airway epithelial cells. In this study, we focused our study on the role of other receptors for dsRNA, such as retinoic acid-inducible gene I (RIG-I), melanoma differentiation-associated gene 5 (MDA-5), and double-stranded RNA-dependent protein kinase (PKR). METHODS Airway epithelial cell BEAS-2B was cultured in vitro. Expression of target RNA and protein were analyzed by PCR and ELISA. To analyze the role of receptors for dsRNA, knockdown of theses genes was performed with short interfering RNA (siRNA). RESULTS We first investigated the effects of chloroquine, an inhibitor of lysosomal acidification, on the expression of chemokines. Preincubation with 100 microM chloroquine significantly inhibited the expression of mRNA for RANTES, IP-10, and IL-8, stimulated by poly I:C, indicating that poly I:C may react with a receptor expressed inside the cells. RIG-I, MDA-5, and PKR are supposed to be expressed inside the airway epithelial cells. However, the expression of chemokines stimulated with poly I:C was not significantly inhibited for these putative receptors in the cells which were transfected with siRNA. CONCLUSIONS Synthetic dsRNA poly I:C stimulates the expression of inflammatory chemokines in airway epithelial cells, but the putative receptors for dsRNA such as RIG-I, MDA-5, or PKR may not play pivotal roles in this process. TLR3 may play a major role as reported previously.
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MESH Headings
- Bronchi/cytology
- Bronchi/metabolism
- Cell Line, Transformed
- Chemokine CCL5/biosynthesis
- Chemokine CCL5/genetics
- Chemokine CXCL10
- Chemokines, CXC/biosynthesis
- Chemokines, CXC/genetics
- Chloroquine/pharmacology
- DEAD Box Protein 58
- DEAD-box RNA Helicases/antagonists & inhibitors
- DEAD-box RNA Helicases/genetics
- DEAD-box RNA Helicases/physiology
- Enzyme-Linked Immunosorbent Assay
- Epithelial Cells/drug effects
- Epithelial Cells/metabolism
- Humans
- Inflammation
- Interferon-Induced Helicase, IFIH1
- Interleukin-8/biosynthesis
- Interleukin-8/genetics
- Poly I-C/pharmacology
- Polymerase Chain Reaction
- RNA Interference
- RNA, Double-Stranded/pharmacology
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- RNA, Small Interfering/pharmacology
- Receptors, Cell Surface/drug effects
- Receptors, Cell Surface/physiology
- Receptors, Immunologic
- Toll-Like Receptor 3/drug effects
- Toll-Like Receptor 3/physiology
- eIF-2 Kinase/antagonists & inhibitors
- eIF-2 Kinase/genetics
- eIF-2 Kinase/physiology
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Affiliation(s)
- Satoshi Matsukura
- First Department of Internal Medicine, Showa University School of Medicine, Shinagawa, Tokyo, Japan.
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Matsukura S, Kokubu F, Kurokawa M, Kawaguchi M, Ieki K, Kuga H, Odaka M, Suzuki S, Watanabe S, Takeuchi H, Kasama T, Adachi M. Synthetic double-stranded RNA induces multiple genes related to inflammation through Toll-like receptor 3 depending on NF-kappaB and/or IRF-3 in airway epithelial cells. Clin Exp Allergy 2007; 36:1049-62. [PMID: 16911361 DOI: 10.1111/j.1365-2222.2006.02530.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND We hypothesized that synthetic double-stranded (ds)RNA may mimic viral infection and induce expression of genes related to inflammation in airway epithelial cells. OBJECTIVE We analysed what gene was up-regulated by synthetic dsRNA poly I : C and then focused this study on the role of Toll-like receptor 3 (TLR3), a receptor of dsRNA and its transcriptional pathway. METHODS Airway epithelial cell BEAS-2B and normal human bronchial epithelial cells were cultured in vitro. Expression of targets RNA and protein were analysed by PCR and ELISA. Localization of TLR3 expression in the cells was analysed with flow cytometry. To analyse the role of TLR3 and transcription factors, knockdown of these genes was performed with short interfering RNA (siRNA). RESULTS Real-time PCR revealed that poly I : C significantly increased the expression of mRNAs for chemokines IP-10, RANTES, LARC, MIP-1alpha, IL-8, GRO-alpha and ENA-78 and cytokines IL-1beta, GM-CSF, IL-6 and the cell adhesion molecule ICAM-1 in both cell types. Increases in protein levels were also observed. Expression of these genes was significantly inhibited in BEAS-2B cells in which TLR3 expression was knocked down. However, pre-treatment with anti-TLR3 mAb, which interferes with the function of TLR3 expressed on the cell surface, did not inhibit the genes expression and these data were concordant with the results that TLR3 was expressed inside airway epithelial cells. The study of siRNA for NF-kappaB and IRF3 showed that they transduce the signal of poly I : C, but their roles were different in each target gene. CONCLUSION TLR3 is expressed inside airway epithelial cells and transduces synthetic dsRNA signals. These signals may increase expression of inflammatory cytokines, chemokines and ICAM-1 through activation of transcription factors NF-kappaB and/or IRF3 in airway epithelial cells.
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Affiliation(s)
- S Matsukura
- First Department of Internal Medicine, Showa University School of Medicine, Tokyo, Japan.
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31
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Niimi K, Asano K, Shiraishi Y, Nakajima T, Wakaki M, Kagyo J, Takihara T, Suzuki Y, Fukunaga K, Shiomi T, Oguma T, Sayama K, Yamaguchi K, Natori Y, Matsumoto M, Seya T, Yamaya M, Ishizaka A. TLR3-mediated synthesis and release of eotaxin-1/CCL11 from human bronchial smooth muscle cells stimulated with double-stranded RNA. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2007; 178:489-95. [PMID: 17182588 DOI: 10.4049/jimmunol.178.1.489] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Respiratory infections with RNA viruses, such as rhinovirus or respiratory syncytial virus, are a major cause of asthma exacerbation, accompanied by enhanced neutrophilic and/or eosinophilic inflammation of the airways. We studied the effects of dsRNA synthesized during RNA virus replication, and of its receptor, TLR3, on the synthesis of eosinophilic chemokines in bronchial smooth muscle cells (BSMC). Synthetic dsRNA, polyinosinic-cystidic acid (poly(I:C)), induced the synthesis of eosinophilic chemokines, eotaxin-1/CCL11 and RANTES/CCL5, from primary cultures of human BSMC, and IL-4 increased synergistically the synthesis of poly(I:C)-induced CCL11. A robust eosinophil chemotactic activity was released from BSMC stimulated with poly(I:C) and IL-4, which was mostly inhibited by preincubation with an anti-CCL11, but not with an anti-CCL5 Ab. Although the immunoreactivity of TLR3 was detectable on the cellular surface of BSMC by flow cytometric analysis, pretreatment with an anti-TLR3-neutralizing Ab failed to block the poly(I:C)-induced synthesis of CCL11. We have determined by confocal laser-scanning microscopy that the immunoreactivity of TLR3 was aggregated intracellularly in poly(I:C)-stimulated BSMC, colocalizing with fluorescein-labeled poly(I:C). The synthesis of CCL11 was prominently inhibited by the transfection of TLR3-specific small interfering RNA or by bafilomycin A1, an endosomal acidification inhibitor, further supporting the essential role played by intracellular TLR3 in the synthesis of poly(I:C)-induced CCL11 in BSMC. In conclusion, these observations suggest that, by activating intracellular TLR3 in BSMC, respiratory RNA virus infections stimulate the production of CCL11 and enhance eosinophilic inflammation of the airways in the Th2-dominant microenvironment.
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Affiliation(s)
- Kyoko Niimi
- Division of Pulmonary Medicine, Department of Medicine, Keio University School of Medicine, Tokyo, Japan
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Yamashita K, Imaizumi T, Taima K, Fujita T, Ishikawa A, Yoshida H, Oyama C, Satoh K. Polyinosinic-polycytidylic acid induces the expression of GRO-alpha in BEAS-2B cells. Inflammation 2006; 29:17-21. [PMID: 16502342 DOI: 10.1007/s10753-006-8964-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Growth-related oncogene protein-alpha (GRO-alpha)/CXCLl is a chemokine that activates neutrophils and plays an important role in inflammatory reactions. Polyinosinic-polycytidylic acid (poly IC) is a synthetic double-stranded RNA (dsRNA), which is a ligand for Toll-like receptor-3. Poly IC mimics viral infection when applied to cells and induces inflammatory and immune responses. In the present study, we found the induction of GRO-alpha in BEAS-2B bronchial epithelial cells treated with poly IC. Pretreatment of cells with 2-aminopurine, an inhibitor for dsRNA-dependent protein kinase (PKR), inhibited the expression of GRO-alpha-induced by poly IC. Overexpression of interferon-regulatory factor-3 (IRF-3) or retinoic-acid inducible gene-I (RIG-I) enhanced the induction of GRO-alpha by poly IC. PKR, IRF-3, and RIG-I may be involved in the poly IC-induced expression of GRO-alpha in BEAS-2B cells. Airway viral infection may elicit GRO-alpha expression in the bronchial epithelium, which may be implicated in inflammatory and immune reactions.
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Affiliation(s)
- Koji Yamashita
- Department of Vascular Biology, Institute of Brain Science, University School of Medicine, Hirosaki, Japan
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Katz S, Harris R, Lau JTY, Chau A. The use of gene expression analysis and proteomic databases in the development of a screening system to determine the value of natural medicinal products. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2006; 3:65-70. [PMID: 16550225 PMCID: PMC1375224 DOI: 10.1093/ecam/nek001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2005] [Accepted: 12/13/2005] [Indexed: 11/17/2022]
Abstract
A rapid throughput screening system involving gene expression analysis was developed in order to investigate the potential of bioactive chemicals contained in natural health products as effective drug therapy, in particular the ability of these chemicals to alleviate the inflammatory response in human airway epithelial cells. A number of databases were searched to retrieve the information needed to properly analyze the gene expression profiles obtained. The gene expression of human bronchial epithelial cells infected with rhinovirus and/or exposed to platelet activating factor was analyzed. Following analysis of the gene expression data the total number of expressed proteins that may potentially act as a marker for monitoring the modulation of airway inflammation was narrowed to 19. Further studies will involve selecting antibodies for these proteins, culturing airway epithelial cells in the presence of extracts of natural health products, extracting the proteins and identifying them by western blot analysis.
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Affiliation(s)
- Sidney Katz
- Division of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, Canada.
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Nakamichi K, Saiki M, Sawada M, Yamamuro Y, Morimoto K, Kurane I. Double-stranded RNA stimulates chemokine expression in microglia through vacuolar pH-dependent activation of intracellular signaling pathways. J Neurochem 2005; 95:273-83. [PMID: 16181431 DOI: 10.1111/j.1471-4159.2005.03354.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
During neurotropic virus infection, microglia act as a source of chemokines, thereby regulating the recruitment of peripheral leukocytes and the multicellular immune response within the CNS. Herein, we present a comprehensive study on the chemokine production by microglia in response to double-stranded RNA (dsRNA), a conserved molecular pattern of virus infection. Transcriptional analyses of chemokine genes revealed that dsRNA strongly induces the expression of CXC chemokine ligand 10 (CXCL10) and CC chemokine ligand 5 (CCL5) in microglia. We also observed that the dsRNA stimulation triggered the activation of signaling pathways mediated by nuclear factor kappaB (NF-kappaB) and mitogen-activated protein kinases (MAPK), including extracellular signal-regulated kinases 1 and 2 (ERK1/2), p38, and c-Jun N-terminal kinase (JNK). The microglial CXCL10 response to dsRNA was induced via NF-kappaB, p38, and JNK pathways, whereas the dsRNA-induced CCL5 production was dependent on JNK, but not on the other signal-transducing molecules tested. In addition, the acidic environment of intracellular vesicles was required for the activation of cellular signaling in response to dsRNA. Taken together, these results suggest that the recognition of dsRNA structure selectively induces the CXCL10 and CCL5 responses in microglia through vacuolar pH-dependent activation of NF-kappaB and MAPK signaling pathways.
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Affiliation(s)
- Kazuo Nakamichi
- Department of Virology 1, National Institute of Infectious Diseases, Shinjuku, Tokyo, Japan.
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Gil LHVG, van Olphen AL, Mittal SK, Donis RO. Modulation of PKR activity in cells infected by bovine viral diarrhea virus. Virus Res 2005; 116:69-77. [PMID: 16194578 DOI: 10.1016/j.virusres.2005.08.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2005] [Revised: 08/23/2005] [Accepted: 08/24/2005] [Indexed: 01/12/2023]
Abstract
Bovine viral diarrhea virus is an important animal pathogen. The cytopathic and noncytopathic biotypes of the virus are associated with distinct pathologic entities. A striking difference between the two biotypes is viral RNA accumulation in infected cells. Viral dsRNA is thought to activate protein kinase PKR; an important mediator of innate immunity. In this study, we investigated PKR activation and its consequences in BVDV-infected cells. Infection with cp BVDV was found to induce PKR activation, eIF2alpha phosphorylation, translation inhibition and NF-kappaB activation. In contrast, PKR activity and eIF2alpha phosphorylation were not induced during infection with the ncp BVDV. In addition, cells infected with ncp BVDV showed no PKR phosphorylation in response to infection with the unrelated poliovirus whereas uninfected ncp BVDV cells when infected with poliovirus showed high levels of phosphorylated PKR. Cells infected with ncp BVDV failed to respond to synthetic dsRNA (poly I:C) treatment with NF-kappaB activation. However, the NF-kappaB response to bacterial lipopolysaccarides (LPS) was normal in these cells, suggesting a specific suppression of antiviral response signaling in ncp BVDV infected cells. These results indicate that ncp BVDV has evolved specific mechanisms to prevent activation of PKR and its antiviral effectors, most likely to facilitate the establishment and maintenance of persistent infection.
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Affiliation(s)
- Laura H V G Gil
- Department of Veterinary and Biomedical Sciences, University of Nebraska-Lincoln, 68583-0905, USA
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Grissell TV, Powell H, Shafren DR, Boyle MJ, Hensley MJ, Jones PD, Whitehead BF, Gibson PG. Interleukin-10 gene expression in acute virus-induced asthma. Am J Respir Crit Care Med 2005; 172:433-9. [PMID: 15894599 DOI: 10.1164/rccm.200412-1621oc] [Citation(s) in RCA: 159] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE Virus-induced asthma is characterized by marked neutrophil influx and eosinophil degranulation, suggesting a mode of immunopathogenesis different from that of allergen-induced asthma. OBJECTIVES This study compared induced sputum cytokine responses in subjects with severe asthma exacerbation and respiratory virus infection with those of patients with stable asthma, healthy control subjects, and virus-infected nonasthmatic subjects. METHODS Subject infection status and pulmonary history were established on the basis of common cold and asthma questionnaires, and lung function and atopy tests were performed. Respiratory virus infection was diagnosed by cell culture and direct polymerase chain reaction, using induced sputum. The induced sputum cellular profile was examined and cytokine gene expression was assessed by quantitative real-time polymerase chain reaction. RESULTS A respiratory virus was detected in 78% of subjects with acute asthma. Specific viruses detected were rhinovirus (83%), influenza (15%), enterovirus (4%), and respiratory syncytial virus (2%). Virus-infected subjects with acute asthma or no asthma had increased RANTES (regulated on activation, normal T cell expressed and secreted) and macrophage inflammatory protein-1alpha messenger RNAs compared with other groups. Interleukin (IL)-10 mRNA was significantly increased in virus-infected acute asthma and reduced on recovery from acute asthma. IL-5, eotaxin, and IL-8 mRNA transcripts were similar across groups. CONCLUSIONS Asthma exacerbation triggered by respiratory virus infection is characterized by increased IL-10 gene expression that may explain the suppressed eosinophil influx in acute asthma. Airway neutrophilia due to respiratory virus infection is associated with chemokine gene expression involving RANTES and macrophage inflammatory protein-1alpha.
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Affiliation(s)
- Terry V Grissell
- School of Medical Practice and Population Health, University of Newcastle, Callaghan, Australia
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Abstract
PURPOSE OF REVIEW Respiratory viruses are well recognized as major triggers of acute exacerbations of asthma in children and adults, resulting in frequent outpatients visits and hospitalizations. Clinical and epidemiologic evidence supports this association. The application of molecular diagnostic methods has improved understanding of viral epidemiology and the pathophysiological mechanisms involved in viral induced acute asthma. This article reviews publications since October 2002 for an update of the role of viruses in exacerbations of asthma. RECENT FINDINGS Respiratory viruses are present in most patients hospitalized for life-threatening asthma and acute non life-threatening asthma. Rhinovirus is the most common, but coinfection with other viruses may be important. Patients with asthma are not more susceptible to upper respiratory tract rhinovirus infections than healthy people but suffer from more severe consequences of the lower respiratory tract infection. Recent epidemiologic studies suggest that viruses provoke asthma attacks by additive or synergistic interactions with allergen exposure or with air pollution. An impaired antiviral immunity to rhinovirus may lead to impaired viral clearance and hence prolonged symptoms. Respiratory viral infections cause asthmatic exacerbations by triggering recruitment of Th2-type cells into the lungs. There is no specific antiviral strategy for prevention of respiratory-triggered asthma exacerbations, although clinical trials of potential antiviral agents are ongoing. Indirect prevention strategies focus on the reduction of overall airway inflammation to reduce the severity of the host response to respiratory viral infections. SUMMARY Respiratory viral infections are a major cause of morbidity and mortality in asthma. There is a lack of specific antiviral strategies in the prevention or reduction of viral-triggered asthma exacerbations. Recent advances in understanding of the epidemiology and immunopathogenesis of respiratory viral infection in asthma provide opportunities or identification of specific targets for antiviral agents and strategies for management and prevention.
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Affiliation(s)
- Wan C Tan
- Department of Medicine, National University Hospital, Singapore.
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Tsuda M, Matsumoto K, Inoue H, Matsumura M, Nakano T, Mori A, Azuma M, Nakanishi Y. Expression of B7-H1 and B7-DC on the airway epithelium is enhanced by double-stranded RNA. Biochem Biophys Res Commun 2005; 330:263-70. [PMID: 15781259 DOI: 10.1016/j.bbrc.2005.02.161] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2005] [Indexed: 01/22/2023]
Abstract
Viral infection in the airway provokes various immune responses, including Th1 and Th2 responses, which are partly initiated by double-stranded RNA (dsRNA), a viral product for its replication. B7-H1 (PD-L1) and B7-DC (PD-L2) are B7-family molecules that bind to programmed death-1 (PD-1) on lymphocytes and are implicated in peripheral tolerance. We investigated the effect of dsRNA on the expression of B7-H1 and B7-DC on airway epithelial cell lines. B7-H1 and B7-DC were constitutively expressed on the cells, and their expression was profoundly upregulated by stimulation with an analog of viral dsRNA, polyinosinic-polycytidylic acid. B7-H1 and B7-DC were also upregulated by stimulation with IFN-gamma, IL-13, and the supernatant from T cell clones. A relatively high concentration of dexamethasone (1 microM) was required to suppress the upregulation of B7-H1 or B7-DC. These results suggest that epithelial B7-H1 and B7-DC play a role in virus-associated immune responses in the airways.
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Affiliation(s)
- Miyuki Tsuda
- Research Institute for Diseases of the Chest, Graduate School of Medical Sciences, Kyushu University, Maidashi, Higashi-ku, Fukuoka 812-8582, Japan
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Guillot L, Le Goffic R, Bloch S, Escriou N, Akira S, Chignard M, Si-Tahar M. Involvement of toll-like receptor 3 in the immune response of lung epithelial cells to double-stranded RNA and influenza A virus. J Biol Chem 2004; 280:5571-80. [PMID: 15579900 DOI: 10.1074/jbc.m410592200] [Citation(s) in RCA: 526] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Influenza A is a highly contagious single-stranded RNA virus that infects both the upper and lower respiratory tracts of humans. The host innate immune Toll-like receptor (TLR) 3 was shown previously in cells of myeloid origin to recognize the viral replicative, intermediate double-stranded RNA (dsRNA). Thus, dsRNA may be critical for the outcome of the infection. Here we first compared the activation triggered by either influenza A virus or dsRNA in pulmonary epithelial cells. We established that TLR3 is constitutively expressed in human alveolar and bronchial epithelial cells, and we describe its intracellular localization. Expression of TLR3 was positively regulated by the influenza A virus and by dsRNA but not by other inflammatory mediators, including bacterial lipopolysaccharide, the cytokines tumor necrosis factor-alpha and interleukin (IL)-1beta, and the protein kinase C activator phorbol 12-myristate 13-acetate. We also demonstrated that TLR3 contributes directly to the immune response of respiratory epithelial cells to influenza A virus and dsRNA, and we propose a molecular mechanism by which these stimuli induce epithelial cell activation. This model involves mitogen-activated protein kinases, phosphatidylinositol 3-kinase/Akt signaling, and the TLR3-associated adaptor molecule TRIF but not MyD88-dependent activation of the transcription factors NF-kappaB or interferon regulatory factor/interferon-sensitive response-element pathways. Ultimately, this signal transduction elicits an epithelial response that includes the secretion of the cytokines IL-8, IL-6, RANTES (regulated on activation normal T cell expressed and secreted), and interferon-beta and the up-regulation of the major adhesion molecule ICAM-1.
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Affiliation(s)
- Loïc Guillot
- Unité de Défense Innée et Inflammation, INSERM E336, Paris, France
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