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Lara-Hernandez I, Muñoz-Escalante JC, Bernal-Silva S, Noyola DE, Wong-Chew RM, Comas-García A, Comas-Garcia M. Ultrastructural and Functional Characterization of Mitochondrial Dynamics Induced by Human Respiratory Syncytial Virus Infection in HEp-2 Cells. Viruses 2023; 15:1518. [PMID: 37515204 PMCID: PMC10386036 DOI: 10.3390/v15071518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 06/27/2023] [Accepted: 07/05/2023] [Indexed: 07/30/2023] Open
Abstract
Human respiratory syncytial virus (hRSV) is the leading cause of acute lower respiratory tract infections in children under five years of age and older adults worldwide. During hRSV infection, host cells undergo changes in endomembrane organelles, including mitochondria. This organelle is responsible for energy production in the cell and plays an important role in the antiviral response. The present study focuses on characterizing the ultrastructural and functional changes during hRSV infection using thin-section transmission electron microscopy and RT-qPCR. Here we report that hRSV infection alters mitochondrial morphodynamics by regulating the expression of key genes in the antiviral response process, such as Mfn1, VDAC2, and PINK1. Our results suggest that hRSV alters mitochondrial morphology during infection, producing a mitochondrial phenotype with shortened cristae, swollen matrix, and damaged membrane. We also observed that hRSV infection modulates the expression of the aforementioned genes, possibly as an evasion mechanism in the face of cellular antiviral response. Taken together, these results advance our knowledge of the ultrastructural alterations associated with hRSV infection and might guide future therapeutic efforts to develop effective antiviral drugs for hRSV treatment.
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Affiliation(s)
- Ignacio Lara-Hernandez
- High-Resolution Microscopy Section, Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
| | - Juan Carlos Muñoz-Escalante
- Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
- Department of Microbiology, School of Medicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
| | - Sofía Bernal-Silva
- Department of Microbiology, School of Medicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
- Genomic Medicine Section, Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
| | - Daniel E Noyola
- Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
- Department of Microbiology, School of Medicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
| | - Rosa María Wong-Chew
- Research Division, School of Medicine, National Autonomous University of Mexico, Mexico City 04360, Mexico
| | - Andreu Comas-García
- Department of Microbiology, School of Medicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
| | - Mauricio Comas-Garcia
- High-Resolution Microscopy Section, Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
- Science Department, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
- Molecular and Translation Medicine Section, Center for Research in Health Sciences and Biomedicine, Autonomous University of San Luis Potosí, San Luis Potosí 78210, Mexico
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Bivalirudin exerts antiviral activity against respiratory syncytial virus-induced lung infections in neonatal mice. ACTA PHARMACEUTICA (ZAGREB, CROATIA) 2022; 72:415-425. [PMID: 36651544 DOI: 10.2478/acph-2022-0022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/20/2021] [Indexed: 01/26/2023]
Abstract
Respiratory syncytial virus (RSV) is the most common cause of small airways inflammation in the lungs (bronchiolitis) in neonates and immunocompromised adults. The deregulation of cellular and plasma components leads to increased morbidity and mortality. The activation of the clotting cascade plays a key role in the progression of disease severity during viral infection. The current investigation studied the effect of bivalirudin (BR) on the progression and cellular effects of RSV-induced infection in the neonatal mice model. Mice (5-7 days old) were inoculated intranasally with RSV with or without BR administration (2 mg kg-1 day-1, i.v.) for 2 weeks. Tissue histopathology, inflammatory signalling genes such as TLR, and cytokines were analyzed. The results showed pneumocytes exhibiting nuclear pyknosis, cellular infiltration in lung tissue and increased lung titers in RSV-infected mice compared to the control. Furthermore, RSV-infected mice demonstrated altered clotting parameters such as D-dimer, soluble thrombomodulin, and increased inflammatory cytokines IL-5, 6, IFN-γ, IL-13, and CXCL1. Additionally, the mRNA expression analysis displayed increased levels of IL-33, TLR3, and TLR7 genes in RSV-infected lung tissue. Further, to delineate the role of micro RNAs, the qRT-PCR analysis was done, and the results displayed an increase in miR-136, miR-30b, and let-7i. At the same time, the down-regulated expression of miR-221 in RSV-infected mice compared to the control. BR treatment reduced the cellular infiltration with reduced inflammatory cytokines and normalized clotting indices. Thus, the study shows that RSV infection induces specific changes in lung tissue and the clotting related signalling mechanism. Additionally, BR treatment significantly reduces bronchiolitis and prevents the severity of the infections suggesting that BR can possibly be used to reduce the viral-mediated infections in neonates.
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Kurebayashi Y, Bajimaya S, Watanabe M, Lim N, Lutz M, Dunagan M, Takimoto T. Human parainfluenza virus type 1 regulates cholesterol biosynthesis and establishes quiescent infection in human airway cells. PLoS Pathog 2021; 17:e1009908. [PMID: 34529742 PMCID: PMC8445407 DOI: 10.1371/journal.ppat.1009908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 08/19/2021] [Indexed: 12/03/2022] Open
Abstract
Human parainfluenza virus type 1 (hPIV1) and 3 (hPIV3) cause seasonal epidemics, but little is known about their interaction with human airway cells. In this study, we determined cytopathology, replication, and progeny virion release from human airway cells during long-term infection in vitro. Both viruses readily established persistent infection without causing significant cytopathic effects. However, assembly and release of hPIV1 rapidly declined in sharp contrast to hPIV3 due to impaired viral ribonucleocapsid (vRNP) trafficking and virus assembly. Transcriptomic analysis revealed that both viruses induced similar levels of type I and III IFNs. However, hPIV1 induced specific ISGs stronger than hPIV3, such as MX2, which bound to hPIV1 vRNPs in infected cells. In addition, hPIV1 but not hPIV3 suppressed genes involved in lipid biogenesis and hPIV1 infection resulted in ubiquitination and degradation of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, a rate limiting enzyme in cholesterol biosynthesis. Consequently, formation of cholesterol-rich lipid rafts was impaired in hPIV1 infected cells. These results indicate that hPIV1 is capable of regulating cholesterol biogenesis, which likely together with ISGs contributes to establishment of a quiescent infection. Seasonal epidemics caused by parainfluenza viruses result in a significant burden of disease in children. These viruses infect airway epithelial cells and cause acute respiratory infection. Humans are the only known hosts for these viruses, but how these viruses are maintained within the population is not known. In this study, we analyzed human airway cells infected with type 1 and 3 parainfluenza viruses. Both viruses readily established persistent infection without causing major cytopathic effects. However, assembly and release of hPIV1 rapidly declined over time in sharp contrast to hPIV3. HPIV1 infected cells formed large aggregates of viral nucleocapsid at late time points, suggesting impaired nucleocapsid trafficking and virus assembly. Transcriptomic analysis of infected cells showed no major difference in IFN induction between the viruses, while hPIV1 induced elevated levels of interferon stimulated genes (ISGs) compared to hPIV3. Interestingly, hPIV1 infection specifically downregulated genes involved in cholesterol biogenesis. We also found that hPIV1 infection induced ubiquitination and degradation of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, a rate limiting enzyme in cholesterol biosynthesis. These results suggest that induction of IFN-independent ISGs and suppression of cholesterol by hPIV1 likely play a role in establishing quiescent infection in human respiratory epithelial cells.
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Affiliation(s)
- Yuki Kurebayashi
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Shringkhala Bajimaya
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Masahiro Watanabe
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Nicholas Lim
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Michael Lutz
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Megan Dunagan
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, United States of America
| | - Toru Takimoto
- Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, New York, United States of America
- * E-mail:
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Ruiz-Gómez X, Vázquez-Pérez JA, Flores-Herrera O, Esparza-Perusquía M, Santiago-Olivares C, Gaona-Bernal J, Gómez B, Mejía-Nepomuceno F, Méndez C, Rivera-Toledo E. Steady-state persistence of respiratory syncytial virus in a macrophage-like cell line and sequence analysis of the persistent viral genome. Virus Res 2021; 297:198367. [PMID: 33684421 DOI: 10.1016/j.virusres.2021.198367] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Revised: 12/30/2020] [Accepted: 03/01/2021] [Indexed: 01/06/2023]
Abstract
Long-term infection by human respiratory syncytial virus (hRSV) has been reported in immunocompromised patients. Cell lines are valuable in vitro model systems to study mechanisms associated with viral persistence. Persistent infections in cell cultures have been categorized at least as in "carrier-state", where there exist a low proportion of cells infected by a lytic virus, and as in "steady-state", where most of cells are infected, but in absence of cytophatic effect. Here, we showed that hRSV maintained a steady-state persistence in a macrophage-like cell line after 120 passages, since the viral genome was detected in all of the cells analyzed by fluorescence in situ hybridization, whereas only defective viruses were identified by sucrose gradients and titration assay. Interestingly, eight percent of cells harboring the hRSV genome revealed undetectable expression of the viral nucleoprotein N; however, when this cell population was sorted by flow cytometry and independently cultured, viral protein expression was induced at detectable levels since the first post-sorting passage, supporting that sorted cells harbored the viral genome. Sequencing of the persistent hRSV genome obtained from virus collected from cell-culture supernatants, allowed assembling of a complete genome that displayed 24 synonymous and 38 nonsynonymous substitutions in coding regions, whereas extragenic and intergenic regions displayed 12 substitutions, two insertions and one deletion. Previous reports characterizing mutations in extragenic regulatory sequences of hRSV, suggested that some mutations localized at the 3' leader region of our persistent virus might alter viral transcription and replication, as well as assembly of viral nucleocapsids. Besides, substitutions in P, F and G proteins might contribute to altered viral assembly, budding and membrane fusion, reducing the cytopathic effect and in consequence, contributing to host-cell survival. Full-length mutant genomes might be part of the repertoire of defective viral genomes formed during hRSV infections, contributing to the establishment and maintenance of virus persistence.
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Affiliation(s)
- Ximena Ruiz-Gómez
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán, 04510, Mexico City, Mexico.
| | | | - Oscar Flores-Herrera
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán, 04510, Mexico City, Mexico.
| | - Mercedes Esparza-Perusquía
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán, 04510, Mexico City, Mexico.
| | - Carlos Santiago-Olivares
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán, 04510, Mexico City, Mexico.
| | - Jorge Gaona-Bernal
- Departamento de Microbiología y Patología, Centro Universitario de Ciencias de la Salud, Universidad de Guadalajara, Guadalajara, Jalisco, Mexico.
| | - Beatriz Gómez
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán, 04510, Mexico City, Mexico.
| | | | - Carmen Méndez
- Departamento de Embriología y Genética, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán, 04510, Mexico City, Mexico.
| | - Evelyn Rivera-Toledo
- Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán, 04510, Mexico City, Mexico.
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5
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Parrilla E, Armengot M, Mata M, Carda C, Cortijo J, Moratal D, Ginestar D, Hueso JL, Riera J. A Ciliary Motility Index for Activity Measurement in Cell Cultures With Respiratory Syncytial Virus. Am J Rhinol Allergy 2018; 33:121-128. [PMID: 30457015 DOI: 10.1177/1945892418811324] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND The respiratory epithelium is frequently infected by the respiratory syncytial virus, resulting in inflammation, a reduction in cilia activity and an increase in the production of mucus. METHODS In this study, an automatic method has been proposed to characterize the ciliary motility from cell cultures by means of a motility index using a dense optical flow algorithm. This method allows us to determine the ciliary beat frequency (CBF) together with a ciliary motility index of the cells in the cultures. The object of this analysis is to automatically distinguish between normal and infected cells in a culture. RESULTS The method was applied in 2 stages. It was concluded from the first stage that the CBF is not a good enough indicator to discriminate between the control and infected cultures. However, the ciliary motility index does succeed in discriminating between the control and infected cultures using the t test with a value t = 6.46 and P < .001. In the second stage, it has been shown that the ciliary motility index did not differ significantly between patients, and the analysis of variance test gives α = 0.05, F = 1.61, P = .20. A threshold for this index has been determined using a receiver operating characteristics analysis that gives an area under the curve of 0.93. CONCLUSIONS We have obtained a ciliary motility index that is able to discriminate between control and infected cultures after the eighth postinfection day. After infection, there is a rapid cilia loss of the cells and the measured CBF corresponds to the remaining noninfected cells. This is why the CBF does not discriminate between the control and the infected cells.
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Affiliation(s)
- Eduardo Parrilla
- 1 Instituto de Biomecánica de Valencia, Universitat Politècnica de València, Valencia, Spain
| | - Miguel Armengot
- 2 Departament de Cirurgia, Universitat de València, Hospital Universitari i Politècnic la Fe, Valencia, Spain
| | - Manuel Mata
- 3 Departament de Patologia, Universitat de València, Valencia, Spain.,4 Instituto de investigación Sanitaria, Valencia, Spain.,5 Centro de Enfermedades en Red de Enfermedades Respiratorias, Madrid, Spain
| | - Carmen Carda
- 3 Departament de Patologia, Universitat de València, Valencia, Spain.,4 Instituto de investigación Sanitaria, Valencia, Spain.,6 Centro de Enfermedades en Red de Bioingeniería, Zaragoza, Spain
| | - Juilo Cortijo
- 5 Centro de Enfermedades en Red de Enfermedades Respiratorias, Madrid, Spain.,7 Departament de Farmacologia, Universitat de València, Valencia, Spain
| | - David Moratal
- 8 Centro de Biomateriales e Ingeniería Tisular, Universitat Politècnica de València, Valencia, Spain
| | - Damián Ginestar
- 9 Instituto Universitario de Matemática Multidisciplinar, Universitat Politècnica de València, Valencia, Spain
| | - José L Hueso
- 9 Instituto Universitario de Matemática Multidisciplinar, Universitat Politècnica de València, Valencia, Spain
| | - Jaime Riera
- 9 Instituto Universitario de Matemática Multidisciplinar, Universitat Politècnica de València, Valencia, Spain
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Eilam-Frenkel B, Naaman H, Brkic G, Veksler-Lublinsky I, Rall G, Shemer-Avni Y, Gopas J. MicroRNA 146-5p, miR-let-7c-5p, miR-221 and miR-345-5p are differentially expressed in Respiratory Syncytial Virus (RSV) persistently infected HEp-2 cells. Virus Res 2018; 251:34-39. [PMID: 29733865 DOI: 10.1016/j.virusres.2018.05.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2017] [Revised: 04/17/2018] [Accepted: 05/03/2018] [Indexed: 11/15/2022]
Abstract
Many viruses can establish non-cytolytic, chronic infections in host cells. Beyond the intrinsically interesting questions of how this long-term parasitism is achieved, persistently infected cells can be useful to study virus-host interactions. MicroRNAs (miRNAs) are a class of noncoding RNAs transcribed from the genomes of all multicellular organisms and some viruses. Individual miRNAs may regulate several hundred genes. In this research we have studied the expression of a selective group of host-cell encoded miRNAs, as expressed in a Respiratory Syncytial Virus (RSV) persistently infected HEp-2 cell line (HEp-2 + RSV-GFP). The RSV is a virus that does not encode miRNAs in its genome. Our study shows that Dicer is down regulated, miRNA's 146a-5p is strongly up-regulated and miRNAs 345-5p, let-7c-5p and miRNA's-221 are down-regulated in HEp-2 + RSV-GFP cells. Correspondingly, changes in the miRNA 146a-5p and he sequences of the reference genes are miRNA 345-5p respective miRNAs target proteins: HSP-70 and p21, were observed. Thus, RSV persistent viral infection induces unique patterns of miRNA's expression with relevance to how the virus regulates the host cell response to infection.
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Affiliation(s)
- B Eilam-Frenkel
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - H Naaman
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - G Brkic
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - I Veksler-Lublinsky
- Department of Computer Science, Faculty of Engineering Sciences Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - G Rall
- Fox Chase Cancer Center, Dept. of Blood Cell Development and Function, Philadelphia, Pennsylvania, United States
| | - Y Shemer-Avni
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel; Department of Clinical Virology Soroka University Medical Center, Beer Sheva, Israel
| | - J Gopas
- The Shraga Segal Department of Microbiology, Immunology and Genetics, Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel; Department of Oncology, Soroka University Medical Center, Beer Sheva, Israel.
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7
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Conditioned medium from persistently RSV-infected macrophages alters transcriptional profile and inflammatory response of non-infected macrophages. Virus Res 2017; 230:29-37. [DOI: 10.1016/j.virusres.2017.01.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 01/02/2017] [Accepted: 01/03/2017] [Indexed: 11/23/2022]
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Martínez I, García-Carpizo V, Guijarro T, García-Gomez A, Navarro D, Aranda A, Zambrano A. Induction of DNA double-strand breaks and cellular senescence by human respiratory syncytial virus. Virulence 2016; 7:427-42. [PMID: 26809688 DOI: 10.1080/21505594.2016.1144001] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Human respiratory syncytial virus (HRSV) accounts for the majority of lower respiratory tract infections during infancy and childhood and is associated with significant morbidity and mortality. HRSV provokes a proliferation arrest and characteristic syncytia in cellular systems such as immortalized epithelial cells. We show here that HRSV induces the expression of DNA damage markers and proliferation arrest such as P-TP53, P-ATM, CDKN1A and γH2AFX in cultured cells secondary to the production of mitochondrial reactive oxygen species (ROS). The DNA damage foci contained γH2AFX and TP53BP1, indicative of double-strand breaks (DSBs) and could be reversed by antioxidant treatments such as N-Acetylcysteine (NAC) or reduced glutathione ethyl ester (GSHee). The damage observed is associated with the accumulation of senescent cells, displaying a canonical senescent phenotype in both mononuclear cells and syncytia. In addition, we show signs of DNA damage and aging such as γH2AFX and CDKN2A expression in the respiratory epithelia of infected mice long after viral clearance. Altogether, these results show that HRSV triggers a DNA damage-mediated cellular senescence program probably mediated by oxidative stress. The results also suggest that this program might contribute to the physiopathology of the infection, tissue remodeling and aging, and might be associated to long-term consequences of HRSV infections.
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Affiliation(s)
- Isidoro Martínez
- a Department of Molecular Pathology , Spanish National Center for Microbiology, Institute of Health Carlos III , Madrid , Spain
| | - Verónica García-Carpizo
- b Department of Endocrine Physiopathology and Nervous System , Institute for Biomedical Research (IIBM), CSIC-UAM , Madrid , Spain
| | - Trinidad Guijarro
- a Department of Molecular Pathology , Spanish National Center for Microbiology, Institute of Health Carlos III , Madrid , Spain
| | - Ana García-Gomez
- a Department of Molecular Pathology , Spanish National Center for Microbiology, Institute of Health Carlos III , Madrid , Spain
| | - Diego Navarro
- b Department of Endocrine Physiopathology and Nervous System , Institute for Biomedical Research (IIBM), CSIC-UAM , Madrid , Spain
| | - Ana Aranda
- b Department of Endocrine Physiopathology and Nervous System , Institute for Biomedical Research (IIBM), CSIC-UAM , Madrid , Spain
| | - Alberto Zambrano
- a Department of Molecular Pathology , Spanish National Center for Microbiology, Institute of Health Carlos III , Madrid , Spain
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Respiratory Syncytial Virus Persistence in Murine Macrophages Impairs IFN-β Response but Not Synthesis. Viruses 2015; 7:5361-74. [PMID: 26501312 PMCID: PMC4632387 DOI: 10.3390/v7102879] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Revised: 09/11/2015] [Accepted: 10/12/2015] [Indexed: 11/17/2022] Open
Abstract
Type-I interferon (IFN-I) production is an early response to viral infection and pathogenic viruses have evolved multiple strategies to evade this cellular defense. Some viruses can establish and maintain persistent infections by altering the IFN-I signaling pathway. Here, we studied IFN-I synthesis and response in an in vitro model of persistent infection by respiratory syncytial virus (RSV) in a murine macrophage-like cell line. In this model, interferon regulatory factor 3 was constitutively active and located at nuclei of persistently infected cells, inducing expression of IFN-beta mRNA and protein. However, persistently infected macrophages did not respond in an autocrine manner to the secreted-IFN-beta or to recombinant-IFN-beta, since phosphorylated-STAT1 was not detected by western blot and transcription of the interferon-stimulated genes (ISGs) Mx1 and ISG56 was not induced. Treatment of non-infected macrophages with supernatants from persistently infected cells induced STAT1 phosphorylation and ISGs expression, mediated by the IFN-I present in the supernatants, because blocking the IFN-I receptor inhibited STAT1 phosphorylation. Results suggest that the lack of autocrine response to IFN-I by the host cell may be one mechanism for maintenance of RSV persistence. Furthermore, STAT1 phosphorylation and ISGs expression induced in non-infected cells by supernatants from persistently infected macrophages suggest that RSV persistence may trigger a proinflammatory phenotype in non-infected cells as part of the pathogenesis of RSV infection.
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10
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Parrilla E, Armengot M, Mata M, Cortijo J, Riera J, Hueso JL, Moratal D. Ciliary motility activity measurement using a dense optical flow algorithm. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2015; 2013:4446-9. [PMID: 24110720 DOI: 10.1109/embc.2013.6610533] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Persistent respiratory syncytial virus (RSV) infections have been associated with the exacerbation of chronic inflammatory diseases, including chronic obstructive pulmonary disease (COPD). This virus infects the respiratory epithelium, leading to chronic inflammation, and induces the release of mucins and the loss of cilia activity, two factors that determine mucus clearance and the increase in sputum volume. In this study, an automatic method has been established to determine the ciliary motility activity from cell cultures by means of optical flow computation, and has been applied to 136 control cultures and to 144 RSV-infected cultures. The control group presented an average of cell surface with cilia motility per field of 41 ± 15 % (mean ± standard deviation), while the infected group presented a 11 ± 5 %, t-Student p<0.001. The cutoff value to classify a infected specimen was <17.89 % (sensitivity 0.94, specificity 0.93). This methodology has proved to be a robust technique to evaluate cilia motility in cell cultures.
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11
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Zheng J, Yang P, Tang Y, Zhao D. A respiratory syncytial virus persistent-infected cell line system reveals the involvement of SOCS1 in the innate antiviral response. Virol Sin 2015; 30:190-9. [PMID: 26122642 DOI: 10.1007/s12250-015-3597-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Accepted: 06/12/2015] [Indexed: 12/20/2022] Open
Abstract
HEp-2 cells persistently infected with respiratory syncytial virus (RSV) are a heterogeneous mixture of viral antigen-positive and -negative variants; however, the mechanism through which viral replication becomes latent remains unclear. In this study, we investigated the potential mechanism by which RSV escapes from innate immune surveillance. Persistent-infected RSV HEp-2 cells were isolated and cell clones were passaged. The RSV-persistent cells produced viruses at a lower titer, resisted wild-type RSV re-infection, and secreted high levels of interferon-ß (IFN-ß), macrophage inflammatory protein-1α (Mip-1α), interleukin-8 (IL-8), and Rantes. Toll-like receptor 3 (TLR3), retinoic acid inducible gene-I (RIG-I), and suppressor of cytokine signaling 1 (SOCS1) levels were upregulated in these cells. The silencing of TLR3 mRNA decreased the expression of SOCS1 protein and the secretion of cytokines. RSV-persistent cells are in an inflammatory state; upregulation of SOCS1 is related to the TLR3 signaling pathway, which could be associated with the mechanism of viral persistence.
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Affiliation(s)
- Junwen Zheng
- Department of Pediatrics, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan, 430071, China
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12
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Nakamura-Lopez Y, Villegas-Sepúlveda N, Gómez B. RSV P-protein impairs extrinsic apoptosis pathway in a macrophage-like cell line persistently infected with respiratory syncytial virus. Virus Res 2015; 204:82-7. [PMID: 25937519 DOI: 10.1016/j.virusres.2015.04.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 04/22/2015] [Accepted: 04/23/2015] [Indexed: 01/12/2023]
Abstract
Disabling apoptosis is practically a mandatory step for establishing and maintaining viral persistence in host cells. Thus, persisting viruses have evolved strategies to impair apoptosis mechanisms. Apoptosis can be induced through either the intrinsic or the extrinsic pathway. Previously, we reported that staurosporine-induced intrinsic apoptotic pathway was down-regulated in a macrophage cell line persistently infected with respiratory syncytial virus (RSV, MΦP). In the present study, our results showed that the extrinsic apoptotic pathway was also impaired in this cell line and that RSV P-protein interfered with the onset of the extrinsic apoptotic process. In this work, we analyzed and compared the expression of several components of the DISC complex (i.e., TNF-α, TNFR1, caspase-8, and cIAP2) in MΦP cells with that in mock-infected macrophages. Additionally, by using DNA sequence analysis in silico, we searched for an RSV protein putatively interfering with the triggering of the extrinsic apoptotic process. The analysis showed that viral P-protein shared a 52% homology with the caspase-8 death domain. Subsequently, the nucleic acid sequence of the viral P-protein was cloned and transfected into the macrophage cell line; the effect of this transfection on staurosporine-induced apoptosis was evaluated by assaying for cell viability and caspases-8 and -9 activity. The results revealed that although caspase-9 was activated, the activity of the caspase-8 was impaired in the RSV P-protein transfected cells; more of these cells survived than did mock-transfected cells. These findings suggest that P-protein impaired the extrinsic pathway of apoptosis. Our findings contribute to the understanding of the mechanism by which viral proteins subvert the extrinsic apoptosis process in cells persistently infected with RSV.
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Affiliation(s)
- Yuko Nakamura-Lopez
- Laboratory of Virology, Department of Microbiology and Parasitology, Facultad de Medicina, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Ciudad Universitaria, México, D.F. 04360, Mexico.
| | - Nicolas Villegas-Sepúlveda
- Department of Molecular Biomedicine, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508, México, D.F. 07360, Mexico.
| | - Beatriz Gómez
- Laboratory of Virology, Department of Microbiology and Parasitology, Facultad de Medicina, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Ciudad Universitaria, México, D.F. 04360, Mexico.
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Gaona J, Santiago-Olivares C, Ortega E, Gómez B. Respiratory syncytial virus persistence in macrophages upregulates Fcgamma receptors expression. Viruses 2014; 6:624-39. [PMID: 24509813 PMCID: PMC3939475 DOI: 10.3390/v6020624] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2013] [Revised: 11/29/2013] [Accepted: 01/15/2014] [Indexed: 12/13/2022] Open
Abstract
Viruses can persist in differentiated cells (i.e., macrophages) over long periods of time, altering host cells functions but not inducing their death. We had previously reported that, in early passages (14–40) of a murine macrophage-like cell line persistently infected with respiratory syncytial virus (RSV) (MɸP), FcγR-mediated phagocytosis and expression of FcγRIIB/RIII on the cell membrane were increased with respect to mock-infected macrophages (MɸN). In this work, we explored the mechanism underlying such effects. Increases in FcγR expression and FcγR-mediated phagocytosis are preserved after more than 87 passages of the persistently infected culture. We analyzed the expression of FcγR isoforms at both mRNA and protein levels, and found out that RSV persistence distinctly affects the expression of FcγR isoforms. We also observed that the increase in FcγRs expression results neither from soluble factors (cytokines) or viral products released by the infected cells, nor from an increase in the rate of FcγR internalization. Our results suggest that RSV persistence in macrophages induce intracellular effects that have an impact on FcγRs gene expression at both mRNA and protein levels, and that the characteristics of RSV persistence were preserved for over 87 passages.
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Affiliation(s)
- Jorge Gaona
- Department of Microbiology and Parasitology, Faculty of Medicine, National Autonomous University of Mexico (UNAM), Ciudad Universitaria, D.F. Mexico C.P. 04510, Mexico.
| | - Carlos Santiago-Olivares
- Department of Microbiology and Parasitology, Faculty of Medicine, National Autonomous University of Mexico (UNAM), Ciudad Universitaria, D.F. Mexico C.P. 04510, Mexico.
| | - Enrique Ortega
- Department of Immunology, Biomedical Research Institute, National Autonomous University of Mexico (UNAM), Ciudad Universitaria, D.F. México C.P. 04510, Mexico.
| | - Beatriz Gómez
- Department of Microbiology and Parasitology, Faculty of Medicine, National Autonomous University of Mexico (UNAM), Ciudad Universitaria, D.F. Mexico C.P. 04510, Mexico.
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Tiwari PM, Eroglu E, Boyoglu-Barnum S, He Q, Willing GA, Vig K, Dennis VA, Singh SR. Atomic force microscopic investigation of respiratory syncytial virus infection in HEp-2 cells. J Microsc 2013; 253:31-41. [PMID: 24251370 DOI: 10.1111/jmi.12095] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2013] [Accepted: 10/07/2013] [Indexed: 01/14/2023]
Abstract
Respiratory syncytial virus (RSV) primarily causes bronchiolitis and pneumonia in infants. In spite of intense research, no safe and effective vaccine has been developed yet. For understanding its pathogenesis and development of anti-RSV drugs/therapeutics, it is indispensable to study the RSV-host interaction. Although, there are limited studies using electron microscopy to elucidate the infection process of RSV, to our knowledge, no study has reported the morphological impact of RSV infection using atomic force microscopy. We report the cytoplasmic and nuclear changes in human epidermoid cell line type 2 using atomic force microscopy. Human epidermoid cell line type 2 cells, grown on cover slips, were infected with RSV and fixed after various time periods, processed and observed for morphological changes using atomic force microscopy. RSV infected cells showed loss of membrane integrity, with degeneration in the cellular content and cytoskeleton. Nuclear membrane was disintegrated and nuclear volume was decreased. The chromatin of the RSV infected cells was condensed, progressing towards degeneration via pyknosis and apoptosis. Membrane protrusions of ~150-200 nm diameter were observed on RSV infected cells after 6 h, suggestive of prospective RSV budding sites. To our knowledge, this is the first study of RSV infection process using atomic force microscopy. Such morphological studies could help explore viral infection process aiding the development of anti-RSV therapies.
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Affiliation(s)
- P M Tiwari
- Center for NanoBiotechnology Research, Alabama State University, Montgomery, Alabama 36101, U.S.A
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15
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Kimura H, Yoshizumi M, Ishii H, Oishi K, Ryo A. Cytokine production and signaling pathways in respiratory virus infection. Front Microbiol 2013; 4:276. [PMID: 24062733 PMCID: PMC3774987 DOI: 10.3389/fmicb.2013.00276] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 08/26/2013] [Indexed: 12/13/2022] Open
Abstract
It has been confirmed that respiratory virus infections can induce abberant cytokine production in the host. These cytokines may be associated with both elimination of the virus and complications in the host, such as virus-induced asthma. Representative host defense mechanisms against pathogens, including bacteria and viruses, are mediated by the innate immune system. Cells of the innate immune system express essential molecules, namely pattern recognition receptors (PRRs), such as Toll-like receptors, nucleotide-binding oligomerization domain-like receptors, and retinoic acid-inducible gene-I-like receptors. These PRRs can recognize components of pathogens such as bacterial lipopolysaccharide, viral antigens, and their genomes (DNA and RNA). Furthermore, PRRs activate various signaling pathways resulting in cytokine production against pathogen infection. However, the exact mechanisms remain unknown. In this review, we mainly focus on the representative mechanisms of cytokine production through PRRs and signaling pathways due to virus infections, including respiratory virus infections. In addition, we describe the relationships between respiratory infections and virus-induced asthma.
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Affiliation(s)
- Hirokazu Kimura
- Infectious Disease Surveillance Center, National Institute of Infectious Diseases Tokyo, Japan ; Gunma Prefectural Institute of Public Health and Environmental Sciences Gunma, Japan ; Department of Molecular Biodefence Research, Graduate School of Medicine, Yokohama City University Kanagawa, Japan
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16
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Liu X, Qin X, Xiang Y, Liu H, Gao G, Qin L, Liu C, Qu X. Progressive changes in inflammatory and matrix adherence of bronchial epithelial cells with persistent respiratory syncytial virus (RSV) infection (progressive changes in RSV infection). Int J Mol Sci 2013; 14:18024-40. [PMID: 24005865 PMCID: PMC3794767 DOI: 10.3390/ijms140918024] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2013] [Revised: 08/16/2013] [Accepted: 08/21/2013] [Indexed: 12/11/2022] Open
Abstract
In addition to the acute manifestations of respiratory syncytial virus (RSV), persistent infection may be associated with long-term complications in the development of chronic respiratory diseases. To understand the mechanisms underlying RSV-induced long-term consequences, we established an in vitro RSV (strain A2) infection model using human bronchial epithelial (16HBE) cells that persists over four generations and analyzed cell inflammation and matrix adherence. Cells infected with RSV at multiplicity of infection (MOI) 0.0067 experienced cytolytic or abortive infections in the second generation (G2) or G3 but mostly survived up to G4. Cell morphology, leukocyte and matrix adherence of the cells did not change in G1 or G2, but subsequently, leukocyte adherence and cytokine/chemokine secretion, partially mediated by intercellular adhesion molecule-1 (ICAM-1), increased drastically, and matrix adherence, partially mediated by E-cadherin, decreased until the cells died. Tumor necrosis factor-α (TNF-α) secretion was inhibited by ICAM-1 antibody in infected-16HBE cells, suggesting that positive feedback between TNF-α secretion and ICAM-1 expression may be significant in exacerbated inflammation. These data demonstrate the susceptibility of 16HBE cells to RSV and their capacity to produce long-term progressive RSV infection, which may contribute to inflammation mobilization and epithelial shedding.
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Affiliation(s)
- Xiaoai Liu
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410078, China; E-Mails: (X.L.); (Y.X.); (H.L.); (G.G.); (C.L.); (X.Q.)
- Department of Physiology, Guangzhou Medical University, Guangzhou 510182, China
| | - Xiaoqun Qin
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410078, China; E-Mails: (X.L.); (Y.X.); (H.L.); (G.G.); (C.L.); (X.Q.)
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +86-731-8235-5051; Fax: +86-731-8235-5056
| | - Yang Xiang
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410078, China; E-Mails: (X.L.); (Y.X.); (H.L.); (G.G.); (C.L.); (X.Q.)
| | - Huijun Liu
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410078, China; E-Mails: (X.L.); (Y.X.); (H.L.); (G.G.); (C.L.); (X.Q.)
| | - Ge Gao
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410078, China; E-Mails: (X.L.); (Y.X.); (H.L.); (G.G.); (C.L.); (X.Q.)
| | - Ling Qin
- Respiratory Department, Xiangya Hospital, Central South University, Changsha 410078, China; E-Mail:
| | - Chi Liu
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410078, China; E-Mails: (X.L.); (Y.X.); (H.L.); (G.G.); (C.L.); (X.Q.)
| | - Xiangping Qu
- Department of Physiology, School of Basic Medical Science, Central South University, Changsha 410078, China; E-Mails: (X.L.); (Y.X.); (H.L.); (G.G.); (C.L.); (X.Q.)
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Rivera-Toledo E, Gómez B. Respiratory syncytial virus persistence in macrophages alters the profile of cellular gene expression. Viruses 2013; 4:3270-80. [PMID: 23342359 PMCID: PMC3528265 DOI: 10.3390/v4123270] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Viruses can persistently infect differentiated cells through regulation of expression of both their own genes and those of the host cell, thereby evading detection by the host’s immune system and achieving residence in a non-lytic state. Models in vitro with cell lines are useful tools in understanding the mechanisms associated with the establishment of viral persistence. In particular, a model to study respiratory syncytial virus (RSV) persistence in a murine macrophage-like cell line has been established. Compared to non-infected macrophages, macrophages persistently infected with RSV show altered expression both of genes coding for cytokines and trans-membrane proteins associated with antigen uptake and of genes related to cell survival. The biological changes associated with altered gene expression in macrophages as a consequence of persistent RSV infection are summarized.
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Affiliation(s)
- Evelyn Rivera-Toledo
- Department of Microbiology and Parasitology, Faculty of Medicine, Universidad Nacional Autónoma de México, Circuito exterior s/n, Ciudad Universitaria, México D.F., C.P. 04510, Mexico.
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18
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Mata M, Sarrion I, Armengot M, Carda C, Martinez I, Melero JA, Cortijo J. Respiratory syncytial virus inhibits ciliagenesis in differentiated normal human bronchial epithelial cells: effectiveness of N-acetylcysteine. PLoS One 2012; 7:e48037. [PMID: 23118923 PMCID: PMC3485262 DOI: 10.1371/journal.pone.0048037] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 09/20/2012] [Indexed: 01/23/2023] Open
Abstract
Persistent respiratory syncytial virus (RSV) infections have been associated with the exacerbation of chronic inflammatory diseases, including chronic obstructive pulmonary disease (COPD). This virus infects the respiratory epithelium, leading to chronic inflammation, and induces the release of mucins and the loss of cilia activity, two factors that determine mucus clearance and the increase in sputum volume. These alterations involve reactive oxygen species-dependent mechanisms. The antioxidant N-acetylcysteine (NAC) has proven useful in the management of COPD, reducing symptoms, exacerbations, and accelerated lung function decline. NAC inhibits RSV infection and mucin release in human A549 cells. The main objective of this study was to analyze the effects of NAC in modulating ciliary activity, ciliagenesis, and metaplasia in primary normal human bronchial epithelial cell (NHBEC) cultures infected with RSV. Our results indicated that RSV induced ultrastructural abnormalities in axonemal basal bodies and decreased the expression of β-tubulin as well as two genes involved in ciliagenesis, FOXJ1 and DNAI2. These alterations led to a decrease in ciliary activity. Furthermore, RSV induced metaplastic changes to the epithelium and increased the number of goblet cells and the expression of MUC5AC and GOB5. NAC restored the normal functions of the epithelium, inhibiting ICAM1 expression, subsequent RSV infection through mechanisms involving nuclear receptor factor 2, and the expression of heme oxygenase 1, which correlated with the restoration of the antioxidant capacity, the intracellular H(2)O(2) levels and glutathione content of NHBECs. The results presented in this study support the therapeutic use of NAC for the management of chronic respiratory diseases, including COPD.
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Affiliation(s)
- Manuel Mata
- Research Foundation of the University General Hospital of Valencia, Valencia, Spain.
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DeDiego ML, Nieto-Torres JL, Jiménez-Guardeño JM, Regla-Nava JA, Alvarez E, Oliveros JC, Zhao J, Fett C, Perlman S, Enjuanes L. Severe acute respiratory syndrome coronavirus envelope protein regulates cell stress response and apoptosis. PLoS Pathog 2011; 7:e1002315. [PMID: 22028656 PMCID: PMC3197621 DOI: 10.1371/journal.ppat.1002315] [Citation(s) in RCA: 154] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Accepted: 08/29/2011] [Indexed: 12/21/2022] Open
Abstract
Severe acute respiratory syndrome virus (SARS-CoV) that lacks the envelope (E) gene (rSARS-CoV-ΔE) is attenuated in vivo. To identify factors that contribute to rSARS-CoV-ΔE attenuation, gene expression in cells infected by SARS-CoV with or without E gene was compared. Twenty-five stress response genes were preferentially upregulated during infection in the absence of the E gene. In addition, genes involved in signal transduction, transcription, cell metabolism, immunoregulation, inflammation, apoptosis and cell cycle and differentiation were differentially regulated in cells infected with rSARS-CoV with or without the E gene. Administration of E protein in trans reduced the stress response in cells infected with rSARS-CoV-ΔE or with respiratory syncytial virus, or treated with drugs, such as tunicamycin and thapsigargin that elicit cell stress by different mechanisms. In addition, SARS-CoV E protein down-regulated the signaling pathway inositol-requiring enzyme 1 (IRE-1) of the unfolded protein response, but not the PKR-like ER kinase (PERK) or activating transcription factor 6 (ATF-6) pathways, and reduced cell apoptosis. Overall, the activation of the IRE-1 pathway was not able to restore cell homeostasis, and apoptosis was induced probably as a measure to protect the host by limiting virus production and dissemination. The expression of proinflammatory cytokines was reduced in rSARS-CoV-ΔE-infected cells compared to rSARS-CoV-infected cells, suggesting that the increase in stress responses and the reduction of inflammation in the absence of the E gene contributed to the attenuation of rSARS-CoV-ΔE. To identify potential mechanisms mediating the in vivo attenuation of SARS-CoV lacking the E gene (rSARS-CoV-ΔE), the effect of the presence of the E gene on host gene expression was studied. In rSARS-CoV-ΔE-infected cells, the expression of at least 25 stress response genes was preferentially upregulated, compared to cells infected with rSARS-CoV. E protein supplied in trans reversed the increase in stress response genes observed in cells infected with rSARS-CoV-ΔE or with respiratory syncytial virus, and by treatment with drugs causing stress by different mechanisms. Furthermore, in the presence of the E protein a subset (IRE-1 pathway), but not two others (PERK and ATF-6), of the unfolded protein response was also reduced. Nevertheless, the activation of the unfolded protein response to control cell homeostasis was not sufficient to alleviate cell stress, and an increase in cell apoptosis in cells infected with the virus lacking E protein was observed. This apoptotic response was probably induced to protect the host by limiting virus production and dissemination. In cells infected with rSARS-CoV-ΔE, genes associated with the proinflammatory pathway were down-regulated compared to cells infected with virus expressing E protein, supporting the idea that a reduction in inflammation was also relevant in the attenuation of the virus deletion mutant.
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Affiliation(s)
- Marta L DeDiego
- Department of Molecular and Cell Biology, Centro Nacional de Biotecnología (CNB-CSIC), Campus Universidad Autónoma de Madrid, Madrid, Spain
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Nakamura-López Y, Villegas-Sepúlveda N, Sarmiento-Silva RE, Gómez B. Intrinsic apoptotic pathway is subverted in mouse macrophages persistently infected by RSV. Virus Res 2011; 158:98-107. [DOI: 10.1016/j.virusres.2011.03.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2010] [Revised: 03/16/2011] [Accepted: 03/17/2011] [Indexed: 11/29/2022]
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Herranz C, Melero JA, Martínez I. Reduced innate immune response, apoptosis, and virus release in cells cured of respiratory syncytial virus persistent infection. Virology 2011; 410:56-63. [DOI: 10.1016/j.virol.2010.10.035] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2010] [Revised: 08/25/2010] [Accepted: 10/24/2010] [Indexed: 12/24/2022]
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