Cross-talk between Staphylococcus aureus leukocidins-intoxicated macrophages and lung epithelial cells triggers chemokine secretion in an inflammasome-dependent manner

This study evaluated the cytotoxicity of mixtures of citral (CTR) and either benzisothiazolinone (BIT, Mix-CTR-BIT) or triclosan (TCS, Mix-CTR-TCS) in human A549 lung epithelial cells. We investigated the effects of various mix ratios of these common air freshener ingredients on cell viability, cell proliferation, reactive oxygen species (ROS) generation, and DNA damage. Mix-CTR-BIT and Mix-CTR-TCS significantly decreased the viability of lung epithelial cells and inhibited cell growth in a dose-dependent manner. In addition, both mixtures increased ROS generation, compared to that observed in control cells. In particular, cell viability, growth, and morphology were affected upon increase in the proportion of BIT or TCS in the mixture. However, comet analysis showed that treatment of cells with Mix-CTR-BIT or Mix-CTR-TCS did not increase DNA damage. Taken together, these data suggested that increasing the content of biocides in air fresheners might induce cytotoxicity, and that screening these compounds using lung epithelial cells may contribute to hazard assessment.

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Inhibition of acute lethal pulmonary inflammation by the IDO–AhR pathway

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1615280114 ◽

2017 ◽

Vol 114 (29) ◽

pp. E5881-E5890 ◽

Cited By ~ 16

Author(s):

Soung-Min Lee ◽

Ha Young Park ◽

Young-Sill Suh ◽

Eun Hye Yoon ◽

Juyang Kim ◽

...

Keyword(s):

T Cells ◽

Epithelial Cells ◽

Pulmonary Inflammation ◽

Lung Parenchyma ◽

Lung Epithelial Cells ◽

Dependent Manner ◽

Independent Manner ◽

Hematopoietic Stem ◽

Lung Epithelial ◽

Ifn Γ

The lung is a prototypic organ that was evolved to reduce immunopathology during the immune response to potentially hazardous endogenous and exogenous antigens. In this study, we show that donor CD4+ T cells transiently induced expression of indoleamine 2,3-dioxygenase (IDO) in lung parenchyma in an IFN-γ–dependent manner early after allogeneic hematopoietic stem cell transplantation (HSCT). Abrogation of host IDO expression by deletion of the IDO gene or the IFN-γ gene in donor T cells or by FK506 treatment resulted in acute lethal pulmonary inflammation known as idiopathic pneumonia syndrome (IPS). Interestingly, IL-6 strongly induced IDO expression in an IFN-γ–independent manner when deacetylation of STAT3 was inhibited. Accordingly, a histone deacetylase inhibitor (HDACi) could reduce IPS in the state where IFN-γ expression was suppressed by FK506. Finally, l-kynurenine produced by lung epithelial cells and alveolar macrophages during IPS progression suppresses the inflammatory activities of lung epithelial cells and CD4+ T cells through the aryl hydrocarbon receptor pathway. Taken together, our results reveal that IDO is a critical regulator of acute pulmonary inflammation and that regulation of IDO expression by HDACi may be a therapeutic approach for IPS after HSCT.

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SARS-CoV-2 spike protein induces inflammation via TLR2-dependent activation of the NF-κB pathway

10.1101/2021.03.16.435700 ◽

2021 ◽

Author(s):

Shahanshah Khan ◽

Mahnoush S. Shafiei ◽

Christopher Longoria ◽

John Schoggins ◽

Rashmin C. Savani ◽

...

Keyword(s):

Epithelial Cells ◽

Inflammatory Response ◽

Inflammatory Cytokines ◽

Lung Epithelial Cells ◽

Dependent Manner ◽

S Protein ◽

Cytokines And Chemokines ◽

Lung Epithelial ◽

Mouse Macrophages ◽

Human And Mouse

Pathogenesis of COVID-19 is associated with a hyperinflammatory response; however, the precise mechanism of SARS-CoV-2-induced inflammation is poorly understood. Here we investigated direct inflammatory functions of major structural proteins of SARS-CoV-2. We observed that spike (S) protein potently induces inflammatory cytokines and chemokines including IL-6, IL-1b, TNFa, CXCL1, CXCL2, and CCL2, but not IFNs in human and mouse macrophages. No such inflammatory response was observed in response to membrane (M), envelope (E), and neucleocapsid (N) proteins. When stimulated with extracellular S protein, human lung epithelial cells A549 also produce inflammatory cytokines and chemokines. Interestingly, epithelial cells expressing S protein intracellularly are non-inflammatory, but elicit an inflammatory response in macrophages when co-cultured. Biochemical studies revealed that S protein triggers inflammation via activation of the NF-kB pathway in a MyD88-dependent manner. Further, such an activation of the NF-kB pathway is abrogated in Tlr2-deficient macrophages. Consistently, administration of S protein induces IL-6, TNF-a, and IL-1b in wild-type, but not Tlr2-deficient mice. Together these data reveal a mechanism for the cytokine storm during SARS-CoV-2 infection and suggest that TLR2 could be a potential therapeutic target for COVID-19.

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Urokinase induces its own expression in Beas2B lung epithelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00395.2001 ◽

2002 ◽

Vol 283 (2) ◽

pp. L319-L328 ◽

Cited By ~ 20

Author(s):

Sreerama Shetty ◽

Usha R. Pendurthi ◽

Prathap Kumar Shetty Halady ◽

Ali O. Azghani ◽

Steven Idell

Keyword(s):

Epithelial Cells ◽

Tyrosine Kinase ◽

Lung Inflammation ◽

Cellular Proliferation ◽

Kinase Inhibitor ◽

Lung Epithelial Cells ◽

Cell Surface Receptor ◽

Dependent Manner ◽

Amino Terminal ◽

Lung Epithelial

The urokinase-type plasminogen activator (uPA) interacts with its receptor (uPAR) to promote local proteolysis as well as cellular proliferation and migration. These functions contribute to the pathogenesis of lung inflammation and remodeling as well as the growth and invasiveness of lung neoplasms. In this study, we sought to determine if uPA alters its own expression in lung epithelial cells. Using immunoprecipitation and Western and Northern blotting techniques, we found that uPA treatment enhanced uPA expression in Beas2B lung epithelial cells in a time- and concentration-dependent manner. The induction of uPA expression is mediated through its cell surface receptor uPAR and does not require uPA enzymatic activity. The amino-terminal fragment of uPA, lacking the catalytic domain, is sufficient to induce uPA expression. The serine protease plasmin and the protease inhibitor aprotinin failed to alter uPA-mediated uPA expression, whereas α-thrombin potentiated the response. Pretreatment of Beas2B cells with a tyrosine kinase inhibitor, herbimycin, suggests that activation of tyrosine kinase(s) is involved in the uPA-mediated uPA expression. Induction of uPA expression by exposure of lung-derived epithelial cells to uPA is a newly defined pathway by which this protease could influence expression of local fibrinolytic activity and other uPA-dependent cellular responses germane to lung inflammation or neoplasia.

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Cytosolic phospholipase A2α activation induced by S1P is mediated by the S1P3 receptor in lung epithelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00393.2007 ◽

2008 ◽

Vol 295 (2) ◽

pp. L326-L335 ◽

Cited By ~ 23

Author(s):

Li-Yuan Chen ◽

Grzegorz Woszczek ◽

Sahrudaya Nagineni ◽

Carolea Logun ◽

James H. Shelhamer

Keyword(s):

Epithelial Cells ◽

Rho Kinase ◽

A549 Cells ◽

Lung Epithelial Cells ◽

Calcium Flux ◽

Lipid Mediator ◽

Dependent Manner ◽

Cytosolic Phospholipase ◽

Lung Epithelial ◽

Sphingosine 1 Phosphate

Cytosolic phospholipase A2α (cPLA2α) activation is a regulatory step in the control of arachidonic acid (AA) liberation for eicosanoid formation. Sphingosine 1-phosphate (S1P) is a bioactive lipid mediator involved in the regulation of many important proinflammatory processes and has been found in the airways of asthmatic subjects. We investigated the mechanism of S1P-induced AA release and determined the involvement of cPLA2α in these events in A549 human lung epithelial cells. S1P induced AA release rapidly within 5 min in a dose- and time-dependent manner. S1P-induced AA release was inhibited by the cPLA2α inhibitors methyl arachidonyl fluorophosphonate (MAFP) and pyrrolidine derivative, by small interfering RNA-mediated downregulation of cPLA2α, and by inhibition of S1P-induced calcium flux, suggesting a significant role of cPLA2α in S1P-mediated AA release. Knockdown of the S1P3 receptor, the major S1P receptor expressed on A549 cells, inhibited S1P-induced calcium flux and AA release. The S1P-induced calcium flux and AA release was associated with sphingosine kinase 1 (Sphk1) expression and activity. Furthermore, Rho-associated kinase, downstream of S1P3, was crucial for S1P-induced cPLA2α activation. Our data suggest that S1P acting through S1P3, calcium flux, and Rho kinase activates cPLA2α and releases AA in lung epithelial cells. An understanding of S1P-induced cPLA2α activation mechanisms in epithelial cells may provide potential targets to control inflammatory processes in the lung.

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Cigarette Smoke Causes A Residue-Specific Histone Methylation And Its Cross-Talk With Histone Acetylation In Human Lung Epithelial Cells

10.1164/ajrccm-conference.2012.185.1_meetingabstracts.a3474 ◽

2012 ◽

Author(s):

Hongwei Yao ◽

Sangwoon Chung ◽

Isaac K. Sundar ◽

Irfan Rahman

Keyword(s):

Epithelial Cells ◽

Histone Acetylation ◽

Cigarette Smoke ◽

Cross Talk ◽

Histone Methylation ◽

Human Lung ◽

Lung Epithelial Cells ◽

Lung Epithelial ◽

Human Lung Epithelial Cells

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Thrombin Induces NF-κB Activation and IL-8/CXCL8 Expression in Lung Epithelial Cells by a Rac1-dependent PI3K/Akt Pathway

Journal of Biological Chemistry ◽

10.1074/jbc.m110.112433 ◽

2011 ◽

Vol 286 (12) ◽

pp. 10483-10494 ◽

Cited By ~ 40

Author(s):

Chien-Huang Lin ◽

Hui-Wen Cheng ◽

Hon-Ping Ma ◽

Chih-Hsiung Wu ◽

Chuang-Ye Hong ◽

...

Keyword(s):

Epithelial Cells ◽

Human Lung ◽

Luciferase Activity ◽

Lung Epithelial Cells ◽

Akt Pathway ◽

Dependent Manner ◽

Akt Inhibitor ◽

Iκb Kinase ◽

Lung Epithelial ◽

Human Lung Epithelial Cells

We previously showed that thrombin induces interleukin (IL)-8/CXCL8 expression via the protein kinase C (PKC)α/c-Src-dependent IκB kinase α/β (IKKα/β)/NF-κB signaling pathway in human lung epithelial cells. In this study, we further investigated the roles of Rac1, phosphoinositide 3-kinase (PI3K), and Akt in thrombin-induced NF-κB activation and IL-8/CXCL8 expression. Thrombin-induced IL-8/CXCL8 release and IL-8/CXCL8-luciferase activity were attenuated by a PI3K inhibitor (LY294002), an Akt inhibitor (1-l-6-hydroxymethyl-chiro-inositol-2-((R)-2-O-methyl-3-O-octadecylcarbonate)), and the dominant negative mutants of Rac1 (RacN17) and Akt (AktDN). Treatment of cells with thrombin caused activation of Rac and Akt. The thrombin-induced increase in Akt activation was inhibited by RacN17 and LY294002. Stimulation of cells with thrombin resulted in increases in IKKα/β activation and κB-luciferase activity; these effects were inhibited by RacN17, LY294002, an Akt inhibitor, and AktDN. Treatment of cells with thrombin induced Gβγ, p85α, and Rac1 complex formation in a time-dependent manner. These results imply that thrombin activates the Rac1/PI3K/Akt pathway through formation of the Gβγ, Rac1, and p85α complex to induce IKKα/β activation, NF-κB transactivation, and IL-8/CXCL8 expression in human lung epithelial cells.

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Proteome data from a host-pathogen interaction study with Staphylococcus aureus and human lung epithelial cells

Data in Brief ◽

10.1016/j.dib.2016.03.027 ◽

2016 ◽

Vol 7 ◽

pp. 1031-1037 ◽

Cited By ~ 1

Author(s):

Kristin Surmann ◽

Marjolaine Simon ◽

Petra Hildebrandt ◽

Henrike Pförtner ◽

Stephan Michalik ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Epithelial Cells ◽

Human Lung ◽

Lung Epithelial Cells ◽

Interaction Study ◽

Host Pathogen Interaction ◽

Lung Epithelial ◽

Host Pathogen ◽

Human Lung Epithelial Cells

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An In Vitro Model to Assess Early Immune Markers following Co-Exposure of Epithelial Cells to Carbon Black (nano)Particles in the Presence of S. Aureus: Differential Induction of Cytokines.

10.21203/rs.3.rs-907832/v1 ◽

2021 ◽

Author(s):

Scott M Brown ◽

Stephen J Evans ◽

Michael J Burgum ◽

Llinos G Harris ◽

Rowena E Jenkins ◽

...

Keyword(s):

Epithelial Cell ◽

Epithelial Cells ◽

Carbon Black ◽

Human Skin ◽

Lung Epithelial Cells ◽

Nano Particles ◽

Ageing Population ◽

Dependent Manner ◽

Lung Epithelial

Abstract Human exposure to carbon black (CB) is inevitable due to its widespread applications in the medical, industrial and consumer sectors. With an ageing population, it is imperative that the effects of (nano)particle exposure in individuals with compromised immunity or infection are considered. Since barrier immunity provides the first line of defence against CB and the human skin and lung pathogen, Staphylococcus aureus, this work focuses on studying the impact of CB exposure upon compromised immunity during infection on human skin and lung epithelial cells in vitro. The principal aim of the work was to develop an epithelial cell model to characterise (co-)exposure to CB and S. aureus. The work used two human epithelial cell lines, HaCaT (skin) and A549 (lung), ELISA technology to assess the (pro-)inflammatory response, aseptic microbiology techniques to grow S. aureus and a Zetasizer, EDX spectroscopy, and both scanning and transmission electron microscopy (SEM and TEM) to characterise the CB under the conditions used in the study. Physicochemical characterisation of CB confirmed its shape, dramatic polydispersity and potential to aggregate. CB significantly inhibited S. aureus growth, but in a biological media dependent manner. CB did not induce cytokines or antimicrobial peptides from skin and lung epithelial cells, when given alone. In contrast, S. aureus induced a robust interleukin (IL)-8 response in both skin and lung epithelial cells. IL-6 and human beta defensin (hβD)-2 could only be detected when cells were stimulated with S. aureus. However, co-exposure to CB (100µg/ml) and S. aureus resulted in significant inhibition of IL-8 (compared to S. aureus only induced levels). Furthermore, the same co-exposure induced significantly more hβD-2 (compared to S. aureus alone). The ability to detect pathogen responses to particle, in addition to epithelial responses to particle and pathogen is an advance on assessing cell responses under ‘healthy’ conditions and supports the need for developing exposure models under stressed or immunosuppressed conditions. This model will be useful for studying mechanisms of exposure in at-risk groups, including factory workers, the elderly and immunocompromised. Advanced models, that better represent human pathophysiology are essential for understanding cellular mechanisms of toxicity in the 21st Century.

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