Paraoxonase-2 deficiency enhancesPseudomonas aeruginosaquorum sensing in murine tracheal epithelia

2007 ◽  
Vol 292 (4) ◽  
pp. L852-L860 ◽  
Author(s):  
David A. Stoltz ◽  
Egon A. Ozer ◽  
Carey J. Ng ◽  
Janet M. Yu ◽  
Srinivasa T. Reddy ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Quorum Sensing ◽  
Airway Epithelial Cell ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Airway Epithelia ◽  
Tracheal Epithelial Cells ◽  
Human Airway ◽  
Tracheal Epithelial

Pseudomonas aeruginosa is an important cause of nosocomial infections and is frequently present in the airways of cystic fibrosis patients. Quorum sensing mediates P. aeruginosa's virulence and biofilm formation through density-dependent interbacterial signaling with autoinducers. N-3-oxododecanoyl homoserine lactone (3OC12-HSL) is the major autoinducer in P. aeruginosa. We have previously shown that human airway epithelia and paraoxonases (PONs) degrade 3OC12-HSL. This study investigated the role of PON1, PON2, and PON3 in airway epithelial cell inactivation of 3OC12-HSL. All three PONs were present in murine tracheal epithelial cells, with PON2 and PON3 expressed at the highest levels. Lysates of tracheal epithelial cells from PON2, but not PON1 or PON3, knockout mice had impaired 3OC12-HSL inactivation compared with wild-type mice. In contrast, PON1-, PON2-, or PON3-targeted deletions did not affect 3OC12-HSL degradation by intact epithelia. Overexpression of PON2 enhanced 3OC12-HSL degradation by human airway epithelial cell lysates but not by intact epithelia. Finally, using a quorum-sensing reporter strain of P. aeruginosa, we found that quorum sensing was enhanced in PON2-deficient airway epithelia. In summary, these results show that loss of PON2 impairs 3OC12-HSL degradation by airway epithelial cells and suggests that diffusion of 3OC12-HSL into the airway cells can be the rate-limiting step for degradation of the molecule.

scholarly journals Influenza Virus Receptor Specificity and Cell Tropism in Mouse and Human Airway Epithelial Cells

2006 ◽  
Vol 80 (15) ◽  
pp. 7469-7480 ◽  
Author(s):  
Aida Ibricevic ◽  
Andrew Pekosz ◽  
Michael J. Walter ◽  
Celeste Newby ◽  
John T. Battaile ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Airway Epithelial Cell ◽  
Airway Epithelial Cells ◽  
Influenza Viruses ◽  
Mouse Lung ◽  
Airway Epithelial ◽  
Human Airway ◽  
Human Airway Epithelial Cells

ABSTRACT Recent human infections caused by the highly pathogenic avian influenza virus H5N1 strains emphasize an urgent need for assessment of factors that allow viral transmission, replication, and intra-airway spread. Important determinants for virus infection are epithelial cell receptors identified as glycans terminated by an α2,3-linked sialic acid (SA) that preferentially bind avian strains and glycans terminated by an α2,6-linked SA that bind human strains. The mouse is often used as a model for study of influenza viruses, including recent avian strains; however, the selectivity for infection of specific respiratory cell populations is not well described, and any relationship between receptors in the mouse and human lungs is incompletely understood. Here, using in vitro human and mouse airway epithelial cell models and in vivo mouse infection, we found that the α2,3-linked SA receptor was expressed in ciliated airway and type II alveolar epithelial cells and was targeted for cell-specific infection in both species. The α2,6-linked SA receptor was not expressed in the mouse, a factor that may contribute to the inability of some human strains to efficiently infect the mouse lung. In human airway epithelial cells, α2,6-linked SA was expressed and functional in both ciliated and goblet cells, providing expanded cellular tropism. Differences in receptor and cell-specific expression in these species suggest that differentiated human airway epithelial cell cultures may be superior for evaluation of some human strains, while the mouse can provide a model for studying avian strains that preferentially bind only the α2,3-linked SA receptor.

Growth and differentiation of mouse tracheal epithelial cells: selection of a proliferative population

2002 ◽  
Vol 283 (6) ◽  
pp. L1315-L1321 ◽  
Author(s):  
Yingjian You ◽  
Edward J. Richer ◽  
Tao Huang ◽  
Steven L. Brody
Keyword(s):  
Gene Expression ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Airway Epithelial Cell ◽  
Airway Epithelial ◽  
Tracheal Epithelial Cells ◽  
Proliferation And Differentiation ◽  
Tracheal Epithelial

Highly regulated programs for airway epithelial cell proliferation and differentiation during development and repair are often disrupted in disease. These processes have been studied in mouse models; however, it is difficult to isolate and identify epithelial cell-specific responses in vivo. To investigate these processes in vitro, we characterized a model for primary culture of mouse tracheal epithelial cells. Small numbers of cells seeded at low density (7.5 × 104 cells/cm2) rapidly proliferated and became polarized. Subsequently, supplemented media and air-liquid interface conditions resulted in development of highly differentiated epithelia composed of ciliated and nonciliated cells with gene expression characteristic of native airways. Genetically altered or injured mouse tracheal epithelial cells also reflected in vivo patterns of airway epithelial cell gene expression. Passage of cells resulted in continued proliferation but limited differentiation after the first passage, suggesting that transit-amplifying cell populations were present but with independent programs for proliferation and differentiation. This approach provides a high-fidelity in vitro model for evaluation of gene regulation and expression in mouse airway epithelial cells.

scholarly journals FOXO3a regulates rhinovirus-induced innate immune responses in airway epithelial cells

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Joao Gimenes-Junior ◽  
Nicole Owuar ◽  
Hymavathi Reddy Vari ◽  
Wuyan Li ◽  
Nathaniel Xander ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Lung Inflammation ◽  
Inflammatory Cytokine ◽  
Airway Epithelial Cell ◽  
Critical Role ◽  
Airway Epithelial Cells ◽  
Type I ◽  
Airway Epithelial ◽  
Antiviral Responses

AbstractForkhead transcription factor class O (FOXO)3a, which plays a critical role in a wide variety of cellular processes, was also found to regulate cell-type-specific antiviral responses. Airway epithelial cells express FOXO3a and play an important role in clearing rhinovirus (RV) by mounting antiviral type I and type III interferon (IFN) responses. To elucidate the role of FOXO3a in regulating antiviral responses, we generated airway epithelial cell-specific Foxo3a knockout (Scga1b1-Foxo3a−/−) mice and a stable FOXO3a knockout human airway epithelial cell line. Compared to wild-type, Scga1b1-Foxo3a−/− mice show reduced IFN-α, IFN-β, IFN-λ2/3 in response to challenge with RV or double-stranded (ds)RNA mimic, Poly Inosinic-polycytidylic acid (Poly I:C) indicating defective dsRNA receptor signaling. RV-infected Scga1b1-Foxo3a−/− mice also show viral persistence, enhanced lung inflammation and elevated pro-inflammatory cytokine levels. FOXO3a K/O airway epithelial cells show attenuated IFN responses to RV infection and this was associated with conformational change in mitochondrial antiviral signaling protein (MAVS) but not with a reduction in the expression of dsRNA receptors under unstimulated conditions. Pretreatment with MitoTEMPO, a mitochondrial-specific antioxidant corrects MAVS conformation and restores antiviral IFN responses to subsequent RV infection in FOXO3a K/O cells. Inhibition of oxidative stress also reduces pro-inflammatory cytokine responses to RV in FOXO3a K/O cells. Together, our results indicate that FOXO3a plays a critical role in regulating antiviral responses as well as limiting pro-inflammatory cytokine expression. Based on these results, we conclude that FOXO3a contributes to optimal viral clearance and prevents excessive lung inflammation following RV infection.

Erythromycin increases bactericidal activity of surface liquid in human airway epithelial cells

2005 ◽  
Vol 289 (4) ◽  
pp. L565-L573 ◽  
Author(s):  
Kota Ishizawa ◽  
Tomoko Suzuki ◽  
Mutsuo Yamaya ◽  
Yu Xia Jia ◽  
Seiichi Kobayashi ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Bactericidal Activity ◽  
Culture Medium ◽  
Airway Epithelial Cells ◽  
Airway Surface Liquid ◽  
Airway Epithelial ◽  
Tracheal Epithelial Cells ◽  
Tracheal Epithelial ◽  
Surface Liquid ◽  
Number Of Bacteria

Macrolide antibiotics have clinical benefits in patients with diffuse panbronchiolitis and in patients with cystic fibrosis. Although many mechanisms have been proposed, the precise mechanisms are still uncertain. We examined the effects of erythromycin on bactericidal activity of airway surface liquid secreted by cultured human tracheal epithelial cells. Airway surface liquid was collected by washing the surface of human tracheal epithelial cells with a sodium solution (40 meq/l). Methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa were incubated with airway surface liquid, and the number of surviving bacteria was examined. The number of bacteria in airway surface liquid from the cells cultured in medium alone was significantly lower than that in the sodium solution. Furthermore, the number of bacteria in airway surface liquid from the cells treated with erythromycin was significantly lower than that in airway surface liquid from the cells treated with solvent alone. The production of mRNA and protein of human β-defensin-1 and human β-defensin-2 was significantly increased by erythromycin. Bactericidal activity of airway surface liquid was observed at low concentrations (40 meq/l) of sodium but not at higher concentrations (≥80 meq/l). Airway surface liquid did not contain significant amounts of antibiotics supplemented in the culture medium. Erythromycin at the levels in airway surface liquid and in culture medium did not inhibit bacterial growth. These results suggest that erythromycin may increase bactericidal activity of airway surface liquid in human airway epithelial cells through human β-defensins production and reduce susceptibility of the airway to bacterial infection.

Hog barn dust extract augments lymphocyte adhesion to human airway epithelial cells

2004 ◽  
Vol 96 (5) ◽  
pp. 1738-1744 ◽  
Author(s):  
T. Mathisen ◽  
S. G. Von Essen ◽  
T. A. Wyatt ◽  
D. J. Romberger
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Cell Function ◽  
Airway Epithelial Cell ◽  
Airway Epithelial Cells ◽  
Intercellular Adhesion Molecule ◽  
Airway Epithelial ◽  
Intercellular Adhesion Molecule 1 ◽  
Lymphocyte Adhesion ◽  
Dust Extract

The dust of hog confinement facilities induces airway inflammation. Mechanisms by which this dust modulates inflammation are not completely defined, although it is clear that exposure to dust can modulate both epithelial cell and inflammatory cell function. In this work, we demonstrate that airway epithelial cell (BEAS-2B) treatment with hog barn dust extract (HDE) results in augmentation of peripheral blood lymphocyte adhesion to epithelial cell cultures in vitro. The augmentation of lymphocyte adhesion to epithelial cells is dependent on the concentration of HDE and time of HDE exposure, with twofold increases observed by 3 h and maintained at 24 h. Similar results are seen with primary human bronchial epithelial cells in culture. Lymphocyte adhesion to epithelial cells is inhibited in a concentration-dependent fashion by the treatment of epithelial cells with antibody to intercellular adhesion molecule-1 (ICAM-1). In addition, HDE exposure of epithelial cells results in an approximate twofold increase in ICAM-1 expression as determined by flow cytometry analysis. Pretreatment of epithelial cells with a protein kinase C-α (PKC-α) inhibitor, Gö-6976, also inhibited subsequent lymphocyte adhesion to HDE-exposed epithelial cells. These data suggest that airway epithelial cell HDE exposure enhances subsequent lymphocyte adhesion to epithelial cells that is mediated in part by HDE modulation of ICAM-1 expression and PKC-α.

scholarly journals Cooperative effects of rhinovirus and TNF-α on airway epithelial cell chemokine expression

2007 ◽  
Vol 293 (4) ◽  
pp. L1021-L1028 ◽  
Author(s):  
Dawn C. Newcomb ◽  
Umadevi S. Sajjan ◽  
Deepti R. Nagarkar ◽  
Adam M. Goldsmith ◽  
J. Kelley Bentley ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Airway Epithelial Cell ◽  
Chronic Obstructive ◽  
Airway Epithelial ◽  
Obstructive Pulmonary Disease ◽  
Cooperative Effects ◽  
Tracheal Epithelial Cells ◽  
Chemokine Expression ◽  
Tnf Α

Rhinovirus (RV) infections trigger exacerbations of airways disease, but underlying mechanisms remain unknown. We hypothesized that RV and cytokines present in inflamed airways combine to induce augmented airway epithelial cell chemokine expression, promoting further inflammation. To test this hypothesis in a cellular system, we examined the combined effects of RV39 and TNF-α, a cytokine increased in asthma and chronic obstructive pulmonary disease, on airway epithelial cell proinflammatory gene expression. Costimulation of 16HBE14o- human bronchial epithelial cells and primary mucociliary-differentiated tracheal epithelial cells with RV and TNF-α induced synergistic increases in IL-8 and epithelial neutrophil attractant-78 production. Similar synergism was observed for IL-8 promoter activity, demonstrating that the effect is transcriptionally mediated. Whereas increases in ICAM-1 expression and viral load were noted 16–24 h after costimulation, cooperative effects between RV39 and TNF-α were evident 4 h after stimulation and maintained despite incubation with blocking antibody to ICAM-1 given 2 h postinfection or UV irradiation of virus, implying that effects were not solely due to changes in ICAM-1 expression. Furthermore, RV39 infection induced phosphorylation of ERK and transactivation of the IL-8 promoter AP-1 site, which functions as a basal level enhancer, leading to enhanced TNF-α responses. We conclude that RV infection and TNF-α stimulation induce cooperative increases in epithelial cell chemokine expression, providing a cellular mechanism for RV-induced exacerbations of airways disease.

scholarly journals Insulin signaling via the PI3-kinase/Akt pathway regulates airway glucose uptake and barrier function in a CFTR-dependent manner

2017 ◽  
Vol 312 (5) ◽  
pp. L688-L702 ◽  
Author(s):  
Samuel A. Molina ◽  
Hannah K. Moriarty ◽  
Daniel T. Infield ◽  
Barry R. Imhoff ◽  
Rachel J. Vance ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Epithelial Cells ◽  
Small Molecules ◽  
Glucose Uptake ◽  
Glucose Transporter ◽  
Airway Epithelial Cells ◽  
Airway Epithelial ◽  
Airway Epithelia ◽  
Human Airway ◽  
Airway Cells

Cystic fibrosis-related diabetes is the most common comorbidity associated with cystic fibrosis (CF) and correlates with increased rates of lung function decline. Because glucose is a nutrient present in the airways of patients with bacterial airway infections and because insulin controls glucose metabolism, the effect of insulin on CF airway epithelia was investigated to determine the role of insulin receptors and glucose transport in regulating glucose availability in the airway. The response to insulin by human airway epithelial cells was characterized by quantitative PCR, immunoblot, immunofluorescence, and glucose uptake assays. Phosphatidylinositol 3-kinase/protein kinase B (Akt) signaling and cystic fibrosis transmembrane conductance regulator (CFTR) activity were analyzed by pharmacological and immunoblot assays. We found that normal human primary airway epithelial cells expressed glucose transporter 4 and that application of insulin stimulated cytochalasin B-inhibitable glucose uptake, consistent with a requirement for glucose transporter translocation. Application of insulin to normal primary human airway epithelial cells promoted airway barrier function as demonstrated by increased transepithelial electrical resistance and decreased paracellular flux of small molecules. This provides the first demonstration that airway cells express insulin-regulated glucose transporters that act in concert with tight junctions to form an airway glucose barrier. However, insulin failed to increase glucose uptake or decrease paracellular flux of small molecules in human airway epithelia expressing F508del-CFTR. Insulin stimulation of Akt1 and Akt2 signaling in CF airway cells was diminished compared with that observed in airway cells expressing wild-type CFTR. These results indicate that the airway glucose barrier is regulated by insulin and is dysfunctional in CF.

Sign in / Sign up

Export Citation Format

Share Document