Induction of IL-8 byMycoplasma pneumoniaemembrane in BEAS-2B cells

Mycoplasma pne umoniae is an extracellular pathogen, residing on mucosal surfaces of the respiratory and genital tracts. The lack of cell walls in mycoplasmas facilitates the direct contact of the bacterial membrane with the host cell. The cell membrane of mycoplasma is the major inducer of the host pathogenic response. Airway diseases caused by M. pneumoniae include bronchiolitis, bronchitis, and rarely bronchiectasis. In such disorders, neutrophil infiltration of the airways predominates. More recently, M. pneumoniae has been implicated in the pathogenesis of asthma. Epithelial cells play an important role in recruiting inflammatory cells into the airways. Since M. pneumoniae infection of human epithelial cells induces expression of IL-8—a potent activator of neutrophils—we investigated the signaling and transcriptional mechanisms by which mycoplasma membrane induces expression of this chemokine. In BEAS-2B human bronchial epithelial cells, mycoplasma membrane fraction (MMF) increased IL-8 mRNA and protein production. Activation of the transcriptional elements activating protein-1, nuclear factor-interleukin-6, and particularly NF-κB are essential for optimal IL-8 production by MMF. The mitogen-activated protein kinases individually played a modest role in MMF-induced IL-8 production. Toll-like receptor-2 did not play a significant role in MMF-induction of IL-8. Antibiotics with microbicidal activity against M. pneumoniae are also known to have anti-inflammatory effects. Whereas clarithromycin, azithromycin, and moxifloxacin individually were able to inhibit TNF-α-induction of IL-8, each failed to inhibit MMF-induction of IL-8.

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Activation of MAPKs in human bronchial epithelial cells exposed to metals

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1998.275.3.l551 ◽

1998 ◽

Vol 275 (3) ◽

pp. L551-L558 ◽

Cited By ~ 59

Author(s):

James M. Samet ◽

Lee M. Graves ◽

Jacqueline Quay ◽

Lisa A. Dailey ◽

Robert B. Devlin ◽

...

Keyword(s):

Epithelial Cells ◽

Bronchial Epithelial Cells ◽

Human Bronchial Epithelial Cells ◽

Subsequent Increase ◽

Induced Expression ◽

Bronchial Epithelial ◽

Mitogen Activated Protein ◽

Metallic Compounds ◽

Factor Α

We have previously shown that in vitro exposure to metallic compounds enhances expression of interleukin (IL)-6, IL-8, and tumor necrosis factor-α in human bronchial epithelial cells. To characterize signaling pathways involved in metal-induced expression of inflammatory mediators and to identify metals that activate them, we studied the effects of As, Cr, Cu, Fe, Ni, V, and Zn on the mitogen-activated protein kinases (MAPK) extracellular receptor kinase (ERK), c-Jun NH2-terminal kinase (JNK), and P38 in BEAS cells. Noncytotoxic concentrations of As, V, and Zn induced a rapid phosphorylation of MAPK in BEAS cells. Activity assays confirmed marked activation of ERK, JNK, and P38 in BEAS cells exposed to As, V, and Zn. Cr and Cu exposure resulted in a relatively small activation of MAPK, whereas Fe and Ni did not activate MAPK under these conditions. Similarly, the transcription factors c-Jun and ATF-2, substrates of JNK and P38, respectively, were markedly phosphorylated in BEAS cells treated with As, Cr, Cu, V, and Zn. The same acute exposure to As, V, or Zn that activated MAPK was sufficient to induce a subsequent increase in IL-8 protein expression in BEAS cells. These data suggest that MAPK may mediate metal-induced expression of inflammatory proteins in human bronchial epithelial cells.

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Expression of lipocortins in human bronchial epithelial cells: effects of IL-1β , TNF-α, LPS and dexamethasone

Mediators of Inflammation ◽

10.1155/s0962935196000300 ◽

1996 ◽

Vol 5 (3) ◽

pp. 210-217

Author(s):

M. M. Verheggen ◽

H. I. M. de Bont ◽

P. W. C. Adriaansen-Soeting ◽

B. J. A. Goense ◽

C. J. A. M. Tak ◽

...

Keyword(s):

Epithelial Cells ◽

Bronchial Epithelium ◽

Northern Blotting ◽

Bronchial Epithelial Cells ◽

Human Bronchial Epithelial Cells ◽

Bronchial Epithelial ◽

Annexin I ◽

Tnf Α

In this study, we investigated the expression of lipocortin I and II (annexin I and I in the human bronchial epithelium, bothin vivoandin vitro. A clear expression of lipocortin I and II protein was found in the epithelium in sections of bronchial tissue. In cultured human bronchial epithelial cells we demonstrated the expression of lipocortin I and II mRNA and protein using Northern blotting, FACScan analysis and ELISA. No induction of lipocortin I or II mRNA or protein was observed after incubation with dexamethasone. Stimulation of bronchial epithelial cells with IL-1β, TNF-α or LPS for 24 h did not affect the lipocortin I or II mRNA or protein expression, although PGE2and 6-keto-PGF1αproduction was significantly increased. This IL-1β- and LPS-mediated increase in eicosanoids could be reduced by dexamethasone, but was not accompanied by an increase in lipocortin I or II expression. In human bronchial epithelial cells this particular glucocorticoid action is not mediated through lipocortin I or II induction.

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Stimulation of protein kinase C activity by tumor necrosis factor-α in bovine bronchial epithelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1997.273.5.l1007 ◽

1997 ◽

Vol 273 (5) ◽

pp. L1007-L1012 ◽

Cited By ~ 16

Author(s):

Todd A. Wyatt ◽

Harumasa Ito ◽

Thomas J. Veys ◽

John R. Spurzem

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Tumor Necrosis Factor ◽

Epithelial Cells ◽

Tumor Necrosis ◽

Bronchial Epithelial ◽

Calphostin C ◽

Kinase C ◽

Tnf Α ◽

Necrosis Factor

Bronchial epithelial cell migration, attachment, and proliferation are important processes in response to airway injury. We have shown that tumor necrosis factor (TNF)-α stimulates the migration of bovine bronchial epithelial cells (BBEC) in vitro. We hypothesized that protein kinase C (PKC) may be one of the intracellular signaling mediators of TNF-α in BBEC. In this study, we have identified multiple PKC isoforms in BBEC and measured total cellular PKC activity. Polyclonal antibodies to the PKC-α, -β2, -δ, and -ε isoforms recognized protein bands around 80–90 kDa. BBEC primary cultures treated with either 500 U/ml TNF-α for 2–4 h or 100 ng/ml 12- O-tetradecanoylphorbol 13-acetate for 15 min resulted in three- to fivefold increases in PKC activity in the particulate fractions of crude cell lysates. This activity was inhibited by 1 μM calphostin C or 10 μM H-7. Similarly, TNF-α-stimulated BBEC migration was reduced at least twofold in the presence of H-7 or calphostin C. These studies suggest that the activation of PKC is necessary for TNF-α-stimulated BBEC migration.

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Ssc-novel-miR-106-5p reduces lipopolysaccharide-induced inflammatory response in porcine endometrial epithelial cells by inhibiting the expression of the target gene mitogen-activated protein kinase kinase kinase 14 (MAP3K14)

Reproduction Fertility and Development ◽

10.1071/rd19097 ◽

2019 ◽

Vol 31 (10) ◽

pp. 1616

Author(s):

Yu Lian ◽

Yu Hu ◽

Lu Gan ◽

Yuan-Nan Huo ◽

Hong-Yan Luo ◽

...

Keyword(s):

Protein Kinase ◽

Epithelial Cells ◽

Target Gene ◽

Mitogen Activated Protein Kinase ◽

Luciferase Reporter ◽

Nuclear Factor ◽

Tnf Α ◽

Mitogen Activated Protein ◽

Endometrial Epithelial Cells ◽

Protein Kinase Kinase

As an important gram-negative bacterial outer membrane component, lipopolysaccharide (LPS) plays an important role in bacterial-induced endometritis in sows. However, how LPS induces endometritis is unclear. We stimulated sow endometrial epithelial cells (EECs) with LPS and detected cell viability and tumour necrosis factor-α (TNF-α) and interleukin-1 (IL-1) secretion. LPS affected EEC viability and TNF-α and IL-1 secretion in a dose-dependent manner. LPS induced differential expression in 10 of 393 miRNAs in the EECs (downregulated, nine; upregulated, one). MicroRNA (miRNA) high-throughput sequencing of the LPS-induced EECs plus bioinformatics analysis and the dual-luciferase reporter system revealed a novel miRNA target gene: mitogen-activated protein kinase kinase kinase 14 (MAP3K14). Ssc-novel-miR-106-5p mimic, inhibitor and the nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IκBα) phosphorylation inhibitor Bay11–7085 were used to detect EEC nuclear factor-κB phosphorylation levels (p-NF-κB) and TNF-α and IL-1 secretion. MiR-106-5p mimic downregulated MAP3K14 mRNA and protein expression levels, inhibited p-NF-κB levels and decreased IL-1 and TNF-α secretion, whereas miR-106-5p inhibitor had the opposite effect. Bay11–7085 inhibited p-NF-κB expression and TNF-α and IL-1 secretion. These results suggest that LPS downregulates ssc-novel-miR-106-5p expression in sow EECs to increase MAP3K14 expression, which increases p-NF-κB to promote IL-1 and TNF-α secretion.

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IL-4 induces ICAM-1 expression in human bronchial epithelial cells and potentiates TNF-α

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1999.277.1.l58 ◽

1999 ◽

Vol 277 (1) ◽

pp. L58-L64 ◽

Cited By ~ 9

Author(s):

Ilja Striz ◽

Tadashi Mio ◽

Yuichi Adachi ◽

Peggy Heires ◽

Richard A. Robbins ◽

...

Keyword(s):

Epithelial Cell ◽

Epithelial Cells ◽

Adhesion Molecule ◽

Airway Epithelial Cells ◽

Bronchial Epithelial Cells ◽

Intercellular Adhesion Molecule ◽

Human Bronchial Epithelial Cells ◽

Bronchial Epithelial ◽

Macrophage Cells ◽

Tnf Α

Interleukin (IL)-4 is thought to contribute to the Th2 type of immune response and hence the development of allergic reactions such as asthma. In asthmatic patients, the airway epithelium expresses increased amounts of the cell surface adhesion molecule intercellular adhesion molecule (ICAM)-1 (CD54). One cytokine capable of inducing ICAM-1 in airway epithelial cells, tumor necrosis factor-α (TNF-α), is present in asthma. This study evaluated if IL-4 either alone or together with TNF-α costimulation might modulate CD54 expression by human bronchial epithelial cells (HBECs). CD54 positivity increased in response to IL-4 (16 ± 2% positive vs. 3 ± 1%, P < 0.01); greater induction of CD54 resulted from TNF-α (45 ± 2%, P < 0.001). Costimulation with TNF-α plus IL-4 further augmented expression (56 ± 1%, P < 0.05). Immunoperoxidase results were confirmed by flow cytometry. RT-PCR revealed no increase in ICAM-1 mRNA expression under control conditions or after stimulation with IL-4 alone. TNF-α increased IL-4 mRNA, and IL-4 potentiated this. Functionally, IL-4 augmented the adhesion of THP-1 monocyte/macrophage cells to monolayers of HBECs both alone and in the presence of TNF-α. We conclude that 1) IL-4 augments epithelial cell ICAM-1 expression, 2) IL-4 potentiates the adhesion of THP-1 monocyte/macrophage cells to epithelial cells, and 3) modulation of epithelial cell ICAM-1 expression by IL-4 may play a role in the immunopathology of bronchial asthma.

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cAMP-dependent protein kinase activation decreases cytokine release in bronchial epithelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00373.2013 ◽

2014 ◽

Vol 307 (8) ◽

pp. L643-L651 ◽

Cited By ~ 15

Author(s):

Todd A. Wyatt ◽

Jill A. Poole ◽

Tara M. Nordgren ◽

Jane M. DeVasure ◽

Art J. Heires ◽

...

Keyword(s):

Cell Migration ◽

Protein Kinase ◽

Epithelial Cells ◽

Wound Repair ◽

Bronchial Epithelial Cells ◽

Dependent Protein Kinase ◽

Bronchial Epithelial ◽

Cyclic Monophosphate ◽

Tnf Α ◽

Dependent Protein

Lung injury caused by inhalation of dust from swine-concentrated animal-feeding operations (CAFO) involves the release of inflammatory cytokine interleukin 8 (IL-8), which is mediated by protein kinase C-ε (PKC-ε) in airway epithelial cells. Once activated by CAFO dust, PKC-ε is responsible for slowing cilia beating and reducing cell migration for wound repair. Conversely, the cAMP-dependent protein kinase (PKA) stimulates contrasting effects, such as increased cilia beating and an acceleration of cell migration for wound repair. We hypothesized that a bidirectional mechanism involving PKA and PKC regulates epithelial airway inflammatory responses. To test this hypothesis, primary human bronchial epithelial cells and BEAS-2B cells were treated with hog dust extract (HDE) in the presence or absence of cAMP. PKC-ε activity was significantly reduced in cells that were pretreated for 1 h with 8-bromoadenosine 3′,5′-cyclic monophosphate (8-Br-cAMP) before exposure to HDE ( P < 0.05). HDE-induced IL-6, and IL-8 release was significantly lower in cells that were pretreated with 8-Br-cAMP ( P < 0.05). To exclude exchange protein activated by cAMP (EPAC) involvement, cells were pretreated with either 8-Br-cAMP or 8-(4-chlorophenylthio)-2'- O-methyladenosine-3',5'-cyclic monophosphate (8-CPT-2Me-cAMP) (EPAC agonist). 8-CPT-2Me-cAMP did not activate PKA and did not reduce HDE-stimulated IL-6 release. In contrast, 8-Br-cAMP decreased HDE-stimulated tumor necrosis factor (TNF)-α-converting enzyme (TACE; ADAM-17) activity and subsequent TNF-α release ( P < 0.001). 8-Br-cAMP also blocked HDE-stimulated IL-6 and keratinocyte-derived chemokine release in precision-cut mouse lung slices ( P < 0.05). These data show bidirectional regulation of PKC-ε via a PKA-mediated inhibition of TACE activity resulting in reduced PKC-ε-mediated release of IL-6 and IL-8.

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