Induction of Proinflammatory Cytokines from Human Respiratory Epithelial Cells after Stimulation by NontypeableHaemophilus influenzae

ABSTRACT Nontypeable Haemophilus influenzae (NTHi) causes repeated respiratory infections in patients with chronic lung diseases. These infections are characterized by a brisk inflammatory response which results in the accumulation of polymorphonucleated cells in the lungs and is dependent on the expression and secretion of proinflammatory cytokines. We hypothesize that multiple NTHi molecules, including lipooligosaccharide (LOS), mediate cellular interactions with respiratory epithelial cells, leading to the production of proinflammatory cytokines. To address this hypothesis, we exposed 9HTEo− human tracheal epithelial cells to NTHi and compared the resulting profiles of cytokine gene expression and secretion using multiprobe RNase protection assays and enzyme-linked immunosorbent assays (ELISA), respectively. Dose-response experiments demonstrated a maximum stimulation of most cytokines tested, using a ratio of 100 NTHi bacterial cells to 1 9HTEo− tracheal epithelial cell. Compared with purified LOS, NTHi bacterial cells stimulated 3.6- and 4.5-fold increases in epithelial cell expression of interleukin-8 (IL-8) and IL-6 genes, respectively. Similar results were seen with epithelial cell macrophage chemotactic protein 1, IL-1α, IL-1β, and tumor necrosis factor alpha expression. Polymyxin B completely inhibited LOS stimulation but only partially reduced NTHi whole cell stimulation. Taken together, these results suggest that multiple bacterial molecules including LOS contribute to the NTHi stimulation of respiratory epithelial cell cytokine production. Moreover, no correlation was seen between NTHi adherence to epithelial cells mediated by hemagglutinating pili, Hia, HMW1, HMW2, and Hap and epithelial cytokine secretion. These data suggest that bacterial molecules beyond previously described NTHi cell surface adhesins and LOS play a role in the induction of proinflammatory cytokines from respiratory epithelial cells.

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Regulation of Proinflammatory Cytokines in Human Lung Epithelial Cells Infected with Mycoplasma pneumoniae

Infection and Immunity ◽

10.1128/iai.70.7.3649-3655.2002 ◽

2002 ◽

Vol 70 (7) ◽

pp. 3649-3655 ◽

Cited By ~ 85

Author(s):

Jun Yang ◽

W. Craig Hooper ◽

Donald J. Phillips ◽

Deborah F. Talkington

Keyword(s):

Protein Synthesis ◽

Epithelial Cells ◽

Mycoplasma Pneumoniae ◽

Proinflammatory Cytokines ◽

Human Lung ◽

Lung Epithelial Cells ◽

Cytokine Gene Expression ◽

Respiratory Epithelial Cells ◽

Lung Epithelial ◽

Respiratory Epithelial

ABSTRACT Mycoplasma pneumoniae is a small bacterium without a cell wall that causes tracheobronchitis and atypical pneumonia in humans. It has also been associated with chronic conditions, such as arthritis, and extrapulmonary complications, such as encephalitis. Although the interaction of mycoplasmas with respiratory epithelial cells is a critical early phase of pathogenesis, little is known about the cascade of events initiated by infection of respiratory epithelial cells by mycoplasmas. Previous studies have shown that M. pneumoniae can induce proinflammatory cytokines in several different study systems including cultured murine and human monocytes. In this study, we demonstrate that M. pneumoniae infection also induces proinflammatory cytokine expression in A549 human lung carcinoma cells. Infection of A549 cells resulted in increased levels of interleukin-8 (IL-8) and tumor necrosis factor alpha mRNA, and both proteins were secreted into culture medium. IL-1β mRNA also increased after infection and IL-1β protein was synthesized, but it remained intracellular. In contrast, levels of IL-6 and gamma interferon mRNA and protein remained unchanged or undetectable. Using protease digestion and antibody blocking methods, we found that M. pneumoniae cytadherence is important for the induction of cytokines. On the other hand, while M. pneumoniae protein synthesis and DNA synthesis do not appear to be prerequisites for the induction of cytokine gene expression, A549 cellular de novo protein synthesis is responsible for the increased cytokine protein levels. These results suggest a novel role for lung epithelial cells in the pathogenesis of M. pneumoniae infection and provide a better understanding of M. pneumoniae pathology at the cellular level.

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P2‐40: Expression of the SARS‐CoV‐2 receptor ACE2 and proinflammatory cytokines induced by the periodontopathic bacterium Fusobacterium nucleatum in human respiratory epithelial cells

Respirology ◽

10.1111/resp.14150_136 ◽

2021 ◽

Vol 26 (S3) ◽

pp. 128-129

Keyword(s):

Epithelial Cells ◽

Proinflammatory Cytokines ◽

Fusobacterium Nucleatum ◽

Respiratory Epithelial Cells ◽

Human Respiratory Epithelial Cells ◽

Respiratory Epithelial

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Bioassay of a tracheal smooth muscle-constricting factor released by respiratory epithelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1992.263.1.l137 ◽

1992 ◽

Vol 263 (1) ◽

pp. L137-L141 ◽

Cited By ~ 5

Author(s):

J. H. Wilkens ◽

A. Becker ◽

H. Wilkens ◽

M. Emura ◽

M. Riebe-Imre ◽

...

Keyword(s):

Smooth Muscle ◽

Epithelial Cell ◽

Epithelial Cells ◽

Muscle Tone ◽

Lung Epithelial Cells ◽

Epithelial Cell Line ◽

Cell Column ◽

Respiratory Epithelial Cells ◽

Lung Epithelial ◽

Respiratory Epithelial

Epithelium-derived factors of unknown identity have been proposed to modulate airway smooth muscle tone. We developed a novel sensitive bioassay system that allows serial perfusion of cultured respiratory epithelial cells and guinea pig trachea (GPT). GPT responses were assessed as diameter changes by computerized video microscopy (resolution, 15 microns). A permanent hamster lung epithelial cell line was grown on microcarrier beads and perfused in a cell column. When the outflow tubing from the epithelial cell column was connected to the inflow cannula, the detector GPT contracted, reaching 28 +/- 6% of the maximum methacholine (100 microM)-induced contraction (n = 12, P less than 0.001). Perfusion of the cell column with diclofenac (10 microM) or lysin-mono-acetylsalicylic acid (100 microM) abolished the GPT contraction, whereas selective perfusion of the detector GPT with either agent did not block the contraction. Analysis of the effluent of the epithelial cell column demonstrated a significant basal release of prostaglandins F2 alpha and E2 (PGF2 alpha and PGE2) and 6-ketoprostaglandin F1 alpha, whereas only marginal amounts of thromboxane B2 were detected. When given exogenously, PGF2 alpha, PGE2, PGI2, and U-46619 all contracted the GPT. It is concluded that lung epithelial cells can contract GPT by releasing a transferable factor. This factor is likely to be a constrictor cyclooxygenase product that is not produced in epithelium-denuded GPT.

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Zinc chelators inhibit eotaxin, RANTES, and MCP-1 production in stimulated human airway epithelium and fibroblasts

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00406.2002 ◽

2003 ◽

Vol 285 (3) ◽

pp. L719-L729 ◽

Cited By ~ 35

Author(s):

Martin Richter ◽

André M. Cantin ◽

Claudia Beaulieu ◽

Alexandre Cloutier ◽

Pierre Larivée

Keyword(s):

Epithelial Cells ◽

Airway Epithelium ◽

Rnase Protection Assay ◽

Zinc Content ◽

Lung Epithelial Cells ◽

Respiratory Epithelial Cells ◽

Rnase Protection ◽

Human Airway Epithelium ◽

Zinc Chelator ◽

Respiratory Epithelial

Asthma is characterized by an increased production of eosinophil-active C-C chemokines by the airway epithelium. Recent studies have identified the presence of important quantities of labile zinc in the conducting airways. We hypothesized that modulation of this labile zinc could influence the production of proinflammatory chemokines in respiratory epithelial cells. The zinc chelator N,N,N′ ,N′-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) and the heavy metal chelator 2,3-dimercapto-1-propanesulfonic acid (DMPS) were used to reduce the labile zinc content of A549, BEAS-2B, and HFL-1 cells. Northern blot analysis and RNase protection assay were used to study the effects of the zinc chelators on mRNA expression. DMPS and TPEN specifically inhibited the production of eotaxin, regulated on activation, normal T-cell expressed, and presumably secreted, and monocyte chemotactic protein-1 in TNF-α-stimulated respiratory epithelial cells and fibroblasts through labile zinc chelation. The inhibitory effects of DMPS and TPEN were associated with the decreased binding of the zinc-finger transcription factor GATA-1, whereas no change in NF-κB activation was observed. Together these results demonstrate that modulation of the labile pool of zinc can regulate gene expression and protein synthesis of C-C chemokines in lung epithelial cells and fibroblasts.

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CO-CULTURES WITH RESPIRATORY EPITHELIAL CELLS MODULATE CYTOKINE GENE EXPRESSION IN HUMAN MACROPHAGES

Transplantation Journal ◽

10.1097/00007890-201007272-00943 ◽

2010 ◽

Vol 90 ◽

pp. 505

Author(s):

L. Kolesar ◽

E. Brabcova ◽

Y. Pavlova ◽

A. Slavcev ◽

I. Striz

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Cytokine Gene Expression ◽

Cytokine Gene ◽

Respiratory Epithelial Cells ◽

Human Macrophages ◽

Respiratory Epithelial

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Acidosis increases the susceptibility of respiratory epithelial cells toPseudomonas aeruginosa-induced cytotoxicity

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00524.2016 ◽

2017 ◽

Vol 313 (1) ◽

pp. L126-L137 ◽

Cited By ~ 6

Author(s):

Iviana M. Torres ◽

Sally Demirdjian ◽

Jennifer Vargas ◽

Britton C. Goodale ◽

Brent Berwin

Keyword(s):

Epithelial Cell ◽

Epithelial Cells ◽

Antimicrobial Peptides ◽

Bacterial Infection ◽

Cell Cytotoxicity ◽

Bacterial Survival ◽

Ph Homeostasis ◽

Respiratory Epithelial Cells ◽

Underlying Mechanisms ◽

Respiratory Epithelial

Bacterial infection can lead to acidosis of the local microenvironment, which is believed to exacerbate disease pathogenesis; however, the mechanisms by which changes in pH alter disease progression are poorly understood. We test the hypothesis that acidosis enhances respiratory epithelial cell death in response to infection with Pseudomonas aeruginosa. Our findings support the idea that acidosis in the context of P. aeruginosa infection results in increased epithelial cell cytotoxicity due to ExoU intoxication. Importantly, enforced maintenance of neutral pH during P. aeruginosa infection demonstrates that cytotoxicity is dependent on the acidosis. Investigation of the underlying mechanisms revealed that host cell cytotoxicity correlated with increased bacterial survival during an acidic infection that was due to reduced bactericidal activity of host-derived antimicrobial peptides. These findings extend previous reports that the activities of antimicrobial peptides are pH-dependent and provide novel insights into the consequences of acidosis on infection-derived pathology. Therefore, this report provides the first evidence that physiological levels of acidosis increase the susceptibility of epithelial cells to acute Pseudomonas infection and demonstrates the benefit of maintaining pH homeostasis during a bacterial infection.

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