Induction of IL-6 and CCL5 (RANTES) in human respiratory epithelial (A549) cells by clinical isolates of respiratory syncytial virus is strain specific

ABSTRACT Respiratory syncytial virus (RSV) infects small foci of respiratory epithelial cells via infected droplets. Infection induces expression of type I and III interferons (IFNs) and proinflammatory cytokines, the balance of which may restrict viral replication and affect disease severity. We explored this balance by infecting two respiratory epithelial cell lines with low doses of recombinant RSV expressing green fluorescent protein (rgRSV). A549 cells were highly permissive, whereas BEAS-2B cells restricted infection to individual cells or small foci. After infection, A549 cells expressed higher levels of IFN-β-, IFN-λ-, and NF-κB-inducible proinflammatory cytokines. In contrast, BEAS-2B cells expressed higher levels of antiviral interferon-stimulated genes, pattern recognition receptors, and other signaling intermediaries constitutively and after infection. Transcriptome analysis revealed that constitutive expression of antiviral and proinflammatory genes predicted responses by each cell line. These two cell lines provide a model for elucidating critical mediators of local control of viral infection in respiratory epithelial cells. IMPORTANCE Airway epithelium is both the primary target of and the first defense against respiratory syncytial virus (RSV). Whether RSV replicates and spreads to adjacent epithelial cells depends on the quality of their innate immune responses. A549 and BEAS-2B are alveolar and bronchial epithelial cell lines, respectively, that are often used to study RSV infection. We show that A549 cells are permissive to RSV infection and express genes characteristic of a proinflammatory response. In contrast, BEAS-2B cells restrict infection and express genes characteristic of an antiviral response associated with expression of type I and III interferons. Transcriptome analysis of constitutive gene expression revealed patterns that may predict the response of each cell line to infection. This study suggests that restrictive and permissive cell lines may provide a model for identifying critical mediators of local control of infection and stresses the importance of the constitutive antiviral state for the response to viral challenge.

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Fimbria-Mediated Enhanced Attachment of NontypeableHaemophilus influenzae to Respiratory Syncytial Virus-Infected Respiratory Epithelial Cells

Infection and Immunity ◽

10.1128/iai.67.1.187-192.1999 ◽

1999 ◽

Vol 67 (1) ◽

pp. 187-192 ◽

Cited By ~ 62

Author(s):

Zili Jiang ◽

Nobuo Nagata ◽

Edgar Molina ◽

Lauren O. Bakaletz ◽

Hal Hawkins ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

Epithelial Cells ◽

A549 Cells ◽

Respiratory Epithelial Cells ◽

Nthi Strain ◽

Soluble Mediator ◽

Isogenic Mutant Strain ◽

Rsv Infection ◽

Syncytial Virus ◽

Respiratory Epithelial

ABSTRACT Respiratory syncytial virus (RSV) infection is known to predispose children to otitis media and sinusitis due to bacteria such as nontypeable Haemophilus influenzae (NTHI). In this study, we investigated the role of NTHI surface outer membrane protein P5-homologous fimbriae (P5-fimbriae) in attachment to RSV-exposed A549 epithelial cells. Analysis by fluorescence flow cytometry showed that a live P5-fimbriated NTHI strain (NTHIF+) attached to a higher proportion of RSV-exposed A549 cells than to control cells (mean, 68% for RSV versus 29% for control; P = 0.008), while attachment of the P5-fimbriae-deficient isogenic mutant strain (NTHIF−) was significantly lower than in control cells and rose only slightly following RSV exposure (mean, 17% for RSV versus 10% for control, P = 0.229). Attachment of NTHIF+ did not correlate with the amount of RSV antigen expressed by A549 cells. Furthermore, paraformaldehyde-fixed NTHIF+ also demonstrated an enhanced binding to RSV-exposed cells. Observations by transmission electronic microscopy showed that the mean number of bacteria attached per 100 RSV-exposed A549 cells was higher for NTHIF+ than NTHIF− (99 versus 18; P < 0.001). No intracellular bacteria were identified. UV-irradiated conditioned supernatants collected from RSV-infected A549 cultures (UV-cRSV) also enhanced the attachment of NTHIF+ to A549, suggesting the presence of a preformed soluble mediator(s) in UV-cRSV that enhances the expression of receptors for P5-fimbriae on A549 cells. In summary, RSV infection significantly enhances NTHI attachment to respiratory epithelial cells. P5-fimbria is the critical appendage of NTHI that participates in this attachment. In clinical settings, blocking of the P5-fimbria-mediated attachment of NTHIF+ by passive or active immunity may reduce the morbidity due to NTHI during RSV infection.

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Synergistic Upregulation of Interleukin-8 Secretion from Pulmonary Epithelial Cells by Direct and Monocyte-Dependent Effects of Respiratory Syncytial Virus Infection

Journal of Virology ◽

10.1128/jvi.74.18.8425-8433.2000 ◽

2000 ◽

Vol 74 (18) ◽

pp. 8425-8433 ◽

Cited By ~ 26

Author(s):

Lynette H. Thomas ◽

Melissa I. Y. Wickremasinghe ◽

Mike Sharland ◽

Jon S. Friedland

Keyword(s):

Respiratory Syncytial Virus ◽

Epithelial Cells ◽

A549 Cells ◽

Interleukin 8 ◽

Respiratory Epithelial Cells ◽

Necrosis Factor Alpha ◽

Leukocyte Influx ◽

Rsv Infection ◽

Syncytial Virus ◽

Respiratory Epithelial

ABSTRACT Respiratory syncytial virus (RSV) infection is the major cause of severe bronchiolitis in infants. Pathology of this infection is partly due to excessive proinflammatory leukocyte influx mediated by chemokines. Although direct infection of the respiratory epithelium by RSV may induce chemokine secretion, little is known about the role of cytokine networks. We investigated the effects of conditioned medium (CM) from RSV-infected monocytes (RSV-CM) on respiratory epithelial (A549) cell chemokine release. RSV-CM, but not control CM (both at a 1:5 dilution), stimulated interleukin-8 (IL-8) secretion from A549 cells within 2 h, and secretion increased over 72 h to 11,360 ± 1,090 pg/ml without affecting cell viability. In contrast, RSV-CM had only a small effect on RANTES secretion. RSV-CM interacted with direct RSV infection to synergistically amplify IL-8 secretion from respiratory epithelial cells (levels of secretion at 48 h were as follows: RSV-CM alone, 8,140 ± 2,160 pg/ml; RSV alone, 12,170 ± 300 pg/ml; RSV-CM plus RSV, 27,040 ± 5,260 pg/ml; P < 0.05). RSV-CM induced degradation of IκBα within 5 min but did not affect IκBβ. RSV-CM activated transient nuclear binding of NF-κB within 1 h, while activation of NF-IL6 was delayed until 8 h and was still detectable at 24 h. Promoter-reporter analysis demonstrated that NF-κB binding was essential and that NF-IL6 was important for IL-8 promoter activity in RSV-CM-activated cells. Blocking experiments revealed that the effects of RSV-CM depended on monocyte-derived IL-1 but that tumor necrosis factor alpha was not involved in this network. In summary, RSV infection of monocytes results in and amplifies direct RSV-mediated IL-8 secretion from respiratory epithelial cells by an NF-κB-dependent, NF-IL6-requiring mechanism.

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Analysis of respiratory syncytial virus fusion protein from clinical isolates of Korean children in palivizumab era, 2009–2015

Journal of Infection and Chemotherapy ◽

10.1016/j.jiac.2019.02.013 ◽

2019 ◽

Vol 25 (7) ◽

pp. 514-519

Author(s):

Soo-Han Choi ◽

Ki Sup Park ◽

Yae-Jean Kim

Keyword(s):

Respiratory Syncytial Virus ◽

Fusion Protein ◽

Clinical Isolates ◽

Korean Children ◽

Virus Fusion ◽

Syncytial Virus

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Surveillance of Clinical Isolates of Respiratory Syncytial Virus for Palivizumab (Synagis)–Resistant Mutants

The Journal of Infectious Diseases ◽

10.1086/423213 ◽

2004 ◽

Vol 190 (5) ◽

pp. 975-978 ◽

Cited By ~ 45

Author(s):

John P. DeVincenzo ◽

Caroline B. Hall ◽

David W. Kimberlin ◽

Pablo J. Sánchez ◽

William J. Rodriguez ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

Clinical Isolates ◽

Resistant Mutants ◽

Syncytial Virus

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Syncytia Induction by Clinical Isolates of Human Respiratory Syncytial Virus A

Intervirology ◽

10.1159/000480014 ◽

2017 ◽

Vol 60 (1-2) ◽

pp. 56-60 ◽

Cited By ~ 2

Author(s):

Talita Bianca Gagliardi ◽

Miriã Ferreira Criado ◽

José Luiz Proença-Módena ◽

Ariane Mirela Saranzo ◽

Marisa Akiko Iwamoto ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

Human Respiratory Syncytial Virus ◽

Clinical Isolates ◽

Syncytial Virus

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Respiratory syncytial virus increases IL-8 gene expression and protein release in A549 cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1995.269.6.l865 ◽

1995 ◽

Vol 269 (6) ◽

pp. L865-L872 ◽

Cited By ~ 13

Author(s):

M. A. Fiedler ◽

K. Wernke-Dollries ◽

J. M. Stark

Keyword(s):

Gene Expression ◽

Respiratory Syncytial Virus ◽

Viral Replication ◽

Mrna Expression ◽

A549 Cells ◽

Protein Release ◽

Tnf Alpha ◽

Epithelial Cell Line ◽

Airway Epithelial ◽

Syncytial Virus

The mechanism of respiratory syncytial virus (RSV)-induced inflammation in the airways of infants and children is not fully understood. We hypothesized that RSV directly induces interleukin (IL)-8 gene expression in airway epithelial cells, independent of IL-1 beta and tumor necrosis factor-alpha (TNF-alpha) production. Exposure of A549 cells (an airway epithelial cell line) to RSV resulted in increased IL-8 mRNA expression and IL-8 protein release from the cells as early as 2 h after treatment. Neither IL-1 beta nor TNF-alpha (mRNA or protein) were detected. Viral replication was not necessary for the effects of RSV on IL-8 mRNA expression and protein release early in the infectious process. However, sustained levels of increased IL-8 production required RSV replication. A dose-response relationship was observed between the multiplicity of infection and IL-8 production with both active and nonreplicative RSV at the 2-h time point. Both active RSV and nonreplicative RSV increased the transcriptional activity of the 1.6-kb 5' flanking region of the IL-8 gene. Neither active RSV nor nonreplicative RSV increased the stability of the IL-8 mRNA in A549 cells. We conclude that RSV increases IL-8 gene expression in A549 cells in a biphasic pattern independent of viral replication early (2 h) but dependent on viral replication late (24 h).

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Oxidative stress modulates the expression of toll‑like receptor 3 during respiratory syncytial virus infection in human lung epithelial A549 cells

Molecular Medicine Reports ◽

10.3892/mmr.2018.9089 ◽

2018 ◽

Cited By ~ 2

Author(s):

Min‑Min Wang ◽

Min Lu ◽

Chuan‑Long Zhang ◽

Xuan Wu ◽

Jing‑Xian Chen ◽

...

Keyword(s):

Oxidative Stress ◽

Respiratory Syncytial Virus ◽

Virus Infection ◽

Respiratory Syncytial Virus Infection ◽

Human Lung ◽

A549 Cells ◽

Toll Like Receptor ◽

Lung Epithelial ◽

Syncytial Virus

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Respiratory Syncytial Virus Infection Upregulates NLRC5 and Major Histocompatibility Complex Class I Expression through RIG-I Induction in Airway Epithelial Cells

Journal of Virology ◽

10.1128/jvi.00349-15 ◽

2015 ◽

Vol 89 (15) ◽

pp. 7636-7645 ◽

Cited By ~ 20

Author(s):

Xuancheng Guo ◽

Taixiang Liu ◽

Hengfei Shi ◽

Jingjing Wang ◽

Ping Ji ◽

...

Keyword(s):

Respiratory Syncytial Virus ◽

A549 Cells ◽

Class I ◽

Complex Class ◽

Major Histocompatibility ◽

Class I Mhc ◽

Mhc I ◽

Histocompatibility Complex ◽

Rsv Infection ◽

Syncytial Virus

ABSTRACTRespiratory syncytial virus (RSV) is the leading cause of acute respiratory tract viral infection in infants, causing bronchiolitis and pneumonia. The host antiviral response to RSV acts via retinoic acid-inducible gene I (RIG-I). We show here that RSV infection upregulates major histocompatibility complex class I (MHC-I) expression through the induction of NLRC5, a NOD-like, CARD domain-containing intracellular protein that has recently been identified as a class I MHC transactivator (CITA). RSV infection of A549 cells promotes upregulation of NLRC5 via beta interferon (IFN-β) production, since the NLRC5-inducing activity in a conditioned medium from RSV-infected A549 cells was removed by antibody to IFN-β, but not by antibody to IFN-γ. RSV infection resulted in RIG-I upregulation and induction of NLRC5 and MHC-I. Suppression of RIG-I induction significantly blocked NLRC5, as well as MHC-I, upregulation and diminished IRF3 activation. Importantly, Vero cells deficient in interferon production still upregulated MHC-I following introduction of the RSV genome by infection or transfection, further supporting a key role for RIG-I. A model is therefore proposed in which the host upregulates MHC-I expression during RSV infection directly via the induction of RIG-I and NLRC5 expression. Since elevated expression of MHC-I molecules can sensitize host cells to T lymphocyte-mediated cytotoxicity or immunopathologic damage, the results have significant implications for the modification of immunity in RSV disease.IMPORTANCEHuman respiratory syncytial virus (RSV) is the leading cause of bronchiolitis and pneumonia in infants and young children worldwide. Infection early in life is linked to persistent wheezing and allergic asthma in later life, possibly related to upregulation of major histocompatibility class I (MHC-I) on the cell surface, which facilitates cytotoxic T cell activation and antiviral immunity. Here, we show that RSV infection of lung epithelial cells induces expression of RIG-I, resulting in induction of a class I MHC transactivator, NLRC5, and subsequent upregulation of MHC-I. Suppression of RIG-I induction blocked RSV-induced NLRC5 expression and MHC-I upregulation. Increased MHC-I expression may exacerbate the RSV disease condition due to immunopathologic damage, linking the innate immune response to RSV disease.

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