Desialylation of airway epithelial cells during influenza virus infection enhances pneumococcal adhesion via galectin binding

Type A human seasonal influenza (FluA) virus infection causes exacerbations of bronchial asthma and chronic obstructive pulmonary disease (COPD). l-carbocisteine, a mucolytic agent, reduces the frequency of common colds and exacerbations in COPD. However, the inhibitory effects of l-carbocisteine on FluA virus infection are uncertain. We studied the effects of l-carbocisteine on FluA virus infection in airway epithelial cells. Human tracheal epithelial cells were pretreated with l-carbocisteine and infected with FluA virus (H3N2). Viral titers in supernatant fluids, RNA of FluA virus in the cells, and concentrations of proinflammatory cytokines in supernatant fluids, including IL-6, increased with time after infection. l-carbocisteine reduced viral titers in supernatant fluids, RNA of FluA virus in the cells, the susceptibility to FluA virus infection, and concentrations of cytokines induced by virus infection. The epithelial cells expressed sialic acid with an α2,6-linkage (SAα2,6Gal), a receptor for human influenza virus on the cells, and l-carbocisteine reduced the expression of SAα2,6Gal. l-carbocisteine reduced the number of acidic endosomes from which FluA viral RNA enters into the cytoplasm and reduced the fluorescence intensity from acidic endosomes. Furthermore, l-carbocisteine reduced NF-κB proteins including p50 and p65 in the nuclear extracts of the cells. These findings suggest that l-carbocisteine may inhibit FluA virus infection, partly through the reduced expression of the receptor for human influenza virus in the human airway epithelial cells via the inhibition of NF-κB and through increasing pH in endosomes. l-carbocisteine may reduce airway inflammation in influenza virus infection.

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Gene silencing of β-galactosamide α-2,6-sialyltransferase 1 inhibits human influenza virus infection of airway epithelial cells

BMC Microbiology ◽

10.1186/1471-2180-14-78 ◽

2014 ◽

Vol 14 (1) ◽

pp. 78 ◽

Cited By ~ 9

Author(s):

Dong Wu ◽

Wenbo Huang ◽

Yutao Wang ◽

Wenda Guan ◽

Runfeng Li ◽

...

Keyword(s):

Influenza Virus ◽

Epithelial Cells ◽

Virus Infection ◽

Gene Silencing ◽

Influenza Virus Infection ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Human Influenza ◽

Human Influenza Virus

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Clarithromycin Inhibits Type A Seasonal Influenza Virus Infection in Human Airway Epithelial Cells

Journal of Pharmacology and Experimental Therapeutics ◽

10.1124/jpet.109.162149 ◽

2009 ◽

Vol 333 (1) ◽

pp. 81-90 ◽

Cited By ~ 51

Author(s):

Mutsuo Yamaya ◽

Kyoko Shinya ◽

Yukimasa Hatachi ◽

Hiroshi Kubo ◽

Masanori Asada ◽

...

Keyword(s):

Influenza Virus ◽

Epithelial Cells ◽

Virus Infection ◽

Seasonal Influenza ◽

Influenza Virus Infection ◽

Type A ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Human Airway ◽

Human Airway Epithelial Cells

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Local Blockade of Epithelial PDL-1 in the Airways Enhances T Cell Function and Viral Clearance during Influenza Virus Infection

Journal of Virology ◽

10.1128/jvi.02423-13 ◽

2013 ◽

Vol 87 (23) ◽

pp. 12916-12924 ◽

Cited By ~ 41

Author(s):

Beth McNally ◽

Fang Ye ◽

Meredith Willette ◽

Emilio Flaño

Keyword(s):

T Cells ◽

Influenza Virus ◽

T Cell ◽

Virus Infection ◽

Cell Function ◽

Death Receptor ◽

Influenza Virus Infection ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

T Cell Function

In order to maintain the gas exchange function of the lung following influenza virus infection, a delicate orchestration of positive and negative regulatory pathways must be maintained to attain viral eradication while minimizing local inflammation. The programmed death receptor 1 ligand/programmed death receptor 1 (PDL-1/PD-1) pathway plays an important immunoregulatory role, particularly in the context of T cell function. Here, we have shown that influenza virus infection of primary airway epithelial cells strongly enhances PDL-1 expression and does so in an alpha interferon receptor (IFNAR) signaling-dependent manner. PD-1 is expressed primarily on effector T cells in the lung, compared to effector memory and central memory cells, and shortly after influenza virus infection, an increased number of PD-1+T cells are recruited to the airways. Usingin vitrococultures of airway epithelial cells and T cells andin vivomodels of influenza virus infection, we have demonstrated that blockade of airway epithelial PDL-1 improves CD8 T cell function, defined by increased production of gamma interferon (IFN-γ) and granzyme B and expression of CD107ab. Furthermore, PDL-1 blockade in the airways served to accelerate influenza virus clearance and enhance infection recovery. Our findings suggest that local manipulation of the PDL-1/PD-1 axis in the airways may represent a therapeutic alternative during acute influenza virus infection.

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Infection of Differentiated Porcine Airway Epithelial Cells by Influenza Virus: Differential Susceptibility to Infection by Porcine and Avian Viruses

PLoS ONE ◽

10.1371/journal.pone.0028429 ◽

2011 ◽

Vol 6 (12) ◽

pp. e28429 ◽

Cited By ~ 33

Author(s):

Darsaniya Punyadarsaniya ◽

Chi-Hui Liang ◽

Christine Winter ◽

Henning Petersen ◽

Silke Rautenschlein ◽

...

Keyword(s):

Influenza Virus ◽

Epithelial Cells ◽

Differential Susceptibility ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Susceptibility To Infection ◽

Avian Viruses

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The Interferon-Inducible Proteoglycan Testican-2/SPOCK2 Functions as a Protective Barrier against Virus Infection of Lung Epithelial Cells

Journal of Virology ◽

10.1128/jvi.00662-19 ◽

2019 ◽

Vol 93 (20) ◽

Author(s):

Narae Ahn ◽

Woo-Jong Kim ◽

Nari Kim ◽

Han Wook Park ◽

Seung-Woo Lee ◽

...

Keyword(s):

Influenza Virus ◽

Epithelial Cells ◽

Virus Infection ◽

Heparan Sulfate ◽

Cell Attachment ◽

Core Protein ◽

Influenza Virus Infection ◽

Lung Epithelial Cells ◽

Extracellular Compartment ◽

Lung Epithelial

ABSTRACT Proteoglycans function not only as structural components of the extracellular compartment but also as regulators of various cellular events, including cell migration, inflammation, and infection. Many microbial pathogens utilize proteoglycans to facilitate adhesion and invasion into host cells. Here we report a secreted form of a novel heparan sulfate proteoglycan that functions against virus infection. The expression of SPOCK2/testican-2 was significantly induced in virus-infected lungs or in interferon (IFN)-treated alveolar lung epithelial cells. Overexpression from a SPOCK2 expression plasmid alone or the treatment of cells with recombinant SPOCK2 protein efficiently blocked influenza virus infection at the step of viral attachment to the host cell and entry. Moreover, mice treated with purified SPOCK2 were protected against virus infection. Sialylated glycans and heparan sulfate chains covalently attached to the SPOCK2 core protein were critical for its antiviral activity. Neuraminidase (NA) of influenza virus cleaves the sialylated moiety of SPOCK2, thereby blocking its binding to the virus. Our data suggest that IFN-induced SPOCK2 functions as a decoy receptor to bind and block influenza virus infection, thereby restricting entry of the infecting virus into neighboring cells. IMPORTANCE Here we report a novel proteoglycan protein, testican-2/SPOCK2, that prevents influenza virus infection. Testican-2/SPOCK2 is a complex type of secreted proteoglycan with heparan sulfate GAG chains attached to the core protein. SPOCK2 expression is induced upon virus infection or by interferons, and the protein is secreted to an extracellular compartment, where it acts directly to block virus-cell attachment and entry. Treatment with purified testican-2/SPOCK2 protein can efficiently block influenza virus infection in vitro and in vivo. We also identified the heparan sulfate moiety as a key regulatory module for this inhibitory effect. Based on its mode of action (cell attachment/entry blocker) and site of action (extracellular compartment), we propose testican-2/SPOCK2 as a potential antiviral agent that can efficiently control influenza virus infection.

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L-Carbocisteine Inhibits Respiratory Syncytial Virus Infection In Human Airway Epithelial Cells

10.1164/ajrccm-conference.2012.185.1_meetingabstracts.a3292 ◽

2012 ◽

Author(s):

Mutsuo Yamaya ◽

Yukimasa Hatachi ◽

Hiroshi Kubo ◽

Hidekazu Nishimura

Keyword(s):

Respiratory Syncytial Virus ◽

Epithelial Cells ◽

Virus Infection ◽

Respiratory Syncytial Virus Infection ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Human Airway ◽

Syncytial Virus ◽

Human Airway Epithelial Cells

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Avian Influenza Virus A/HK/483/97(H5N1) NS1 Protein Induces Apoptosis in Human Airway Epithelial Cells

Journal of Virology ◽

10.1128/jvi.01712-07 ◽

2008 ◽

Vol 82 (6) ◽

pp. 2741-2751 ◽

Cited By ~ 84

Author(s):

W. Y. Lam ◽

Julian W. Tang ◽

Apple C. M. Yeung ◽

Lawrence C. M. Chiu ◽

Joseph J. Y. Sung ◽

...

Keyword(s):

Influenza Virus ◽

Epithelial Cells ◽

Avian Influenza ◽

Western Blot ◽

Influenza A ◽

Fas Ligand ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Ns1 Protein ◽

Induced Apoptosis

ABSTRACT Avian H5N1 influenza virus causes a remarkably severe disease in humans, with an overall case fatality rate of greater than 50%. Human influenza A viruses induce apoptosis in infected cells, which can lead to organ dysfunction. To verify the role of H5N1-encoded NS1 in inducing apoptosis, the NS1 gene was cloned and expressed in human airway epithelial cells (NCI-H292 cells). The apoptotic events posttransfection were examined by a terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick-end-labeling assay, flow cytometric measurement of propidium iodide, annexin V staining, and Western blot analyses with antibodies specific for proapoptotic and antiapoptotic proteins. We demonstrated that the expression of H5N1 NS1 protein in NCI-H292 cells was sufficient to induce apoptotic cell death. Western blot analyses also showed that there was prominent cleavage of poly(ADP-ribose) polymerase and activation of caspase-3, caspase-7, and caspase-8 during the NS1-induced apoptosis. The results of caspase inhibitor assays further confirmed the involvement of caspase-dependent pathways in the NS1-induced apoptosis. Interestingly, the ability of H5N1 NS1 protein to induce apoptosis was much enhanced in cells pretreated with Fas ligand (the time posttransfection required to reach >30% apoptosis was reduced from 24 to 6 h). Furthermore, 24 h posttransfection, an increase in Fas ligand mRNA expression of about 5.6-fold was detected in cells transfected with H5N1 NS1. In conclusion, we demonstrated that the NS1 protein encoded by avian influenza A virus H5N1 induced apoptosis in human lung epithelial cells, mainly via the caspase-dependent pathway, which encourages further investigation into the potential for the NS1 protein to be a novel therapeutic target.

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