scholarly journals Respiratory Syncytial Virus-Inducible BCL-3 Expression Antagonizes the STAT/IRF and NF-κB Signaling Pathways by Inducing Histone Deacetylase 1 Recruitment to the Interleukin-8 Promoter

2005 ◽  
Vol 79 (24) ◽  
pp. 15302-15313 ◽  
Author(s):  
Mohammad Jamaluddin ◽  
Sanjeev Choudhary ◽  
Shaofei Wang ◽  
Antonella Casola ◽  
Ruksana Huda ◽  
...  

ABSTRACT Respiratory syncytial virus (RSV) is a paramyxovirus that produces airway inflammation, in part by inducing interleukin-8 (IL-8) expression, a CXC-type chemokine, via the NF-κB/RelA and STAT/IRF signaling pathways. In RSV-infected A549 cells, IL-8 transcription attenuates after 24 h in spite of ongoing viral replication and persistence of nuclear RelA, suggesting a mechanism for transcriptional attenuation. RSV infection induces B-cell lymphoma protein -3 (Bcl-3) expression 6 to 12 h after viral infection, at times when IL-8 transcription is inhibited. By contrast, 293 cells, deficient in inducible Bcl-3 expression, show no attenuation of IL-8 transcription. We therefore examined Bcl-3's role in terminating virus-inducible IL-8 transcription. Transient expression of Bcl-3 potently inhibited virus-inducible IL-8 transcription by disrupting both the NF-κB and STAT/IRF pathways. Although previously Bcl-3 was thought to capture 50-kDa NF-κB1 isoforms in the cytoplasm, immunoprecipitation (IP) and electrophoretic mobility shift assays indicate that nuclear Bcl-3 associates with NF-κB1 without affecting DNA binding. Additionally, Bcl-3 potently inhibited the STAT/IRF pathway. Nondenaturing co-IP assays indicate that nuclear Bcl-3 associates with STAT-1 and histone deacetylase 1 (HDAC-1), increasing HDAC-1 recruitment to the IL-8 promoter. Treatment with the HDAC inhibitor trichostatin A blocks attenuation of IL-8 transcription. A nuclear targeting-deficient Bcl-3 is unable to enhance HDAC-1-mediated chemokine repression. Finally, small inhibitory RNA-mediated Bcl-3 “knockdown” resulted in enhanced RSV-induced chemokine expression in A549 cells. These data indicate that Bcl-3 is a virus-inducible inhibitor of chemokine transcription by interfering with the NF-κB and STAT/IRF signaling pathways by complexing with them and recruiting HDAC-1 to attenuate target promoter activity.

2000 ◽  
Vol 26 (1) ◽  
pp. 13-26 ◽  
Author(s):  
Weizu Chen ◽  
Martha M. Monick ◽  
Aaron B. Carter ◽  
Gary W. Hunninghake

2000 ◽  
Vol 74 (18) ◽  
pp. 8425-8433 ◽  
Author(s):  
Lynette H. Thomas ◽  
Melissa I. Y. Wickremasinghe ◽  
Mike Sharland ◽  
Jon S. Friedland

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.


1995 ◽  
Vol 269 (6) ◽  
pp. L865-L872 ◽  
Author(s):  
M. A. Fiedler ◽  
K. Wernke-Dollries ◽  
J. M. Stark

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).


1995 ◽  
Vol 14 (10) ◽  
pp. 919 ◽  
Author(s):  
S. Biswas ◽  
J. S. Friedland ◽  
D. G. Remick ◽  
E. G. Davies ◽  
M. Sharland

2012 ◽  
Vol 9 (1) ◽  
pp. 190 ◽  
Author(s):  
Ruth Levitz ◽  
Rachel Wattier ◽  
Pamela Phillips ◽  
Alexandra Solomon ◽  
Jessica Lawler ◽  
...  

2015 ◽  
Vol 89 (15) ◽  
pp. 7636-7645 ◽  
Author(s):  
Xuancheng Guo ◽  
Taixiang Liu ◽  
Hengfei Shi ◽  
Jingjing Wang ◽  
Ping Ji ◽  
...  

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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