Disparate oxidant gene expression of airway epithelium compared to alveolar macrophages in smokers.
Ontology highlight
ABSTRACT:
SUBMITTER: Carolan BJ
PROVIDER: S-EPMC2787510 | biostudies-literature | 2009 Nov
REPOSITORIES: biostudies-literature
Publications
Disparate oxidant gene expression of airway epithelium compared to alveolar macrophages in smokers.
Carolan Brendan J BJ Harvey Ben-Gary BG Hackett Neil R NR O'Connor Timothy P TP Cassano Patricia A PA Crystal Ronald G RG
Respiratory research 20091117
<h4>Background</h4>The small airway epithelium and alveolar macrophages are exposed to oxidants in cigarette smoke leading to epithelial dysfunction and macrophage activation. In this context, we asked: what is the transcriptome of oxidant-related genes in small airway epithelium and alveolar macrophages, and does their response differ substantially to inhaled cigarette smoke?<h4>Methods</h4>Using microarray analysis, with TaqMan RT-PCR confirmation, we assessed oxidant-related gene expression i ...[more]
Similar Datasets
Project description:Disparate Oxidant-related Gene Expression of Human Small Airway Epithelium Compared to Autologous Alveolar Macrophages in Response to the In Vivo Oxidant Stress of Cigarette Smoking The oxidant burden of cigarette smoking induces lung cell dysfunction, and play a significant role in the pathogenesis of lung disease. Two cell populations directly exposed to the oxidants in cigarette smoke are the small airway epithelium and alveolar macrophages. Of these, the epithelium appears to be more vulnerable to smoking, becoming disordered in differentiation, repair and function, while alveolar macrophages become activated, without becoming diseased. In this context, we asked: for the same individuals, what is the baseline trancriptome of oxidant-related genes in small airway epithelium compared to alveolar macrophages and do the responses of the transcriptome of these 2 cell populations differ substantially to inhaled cigarette smoke? To address these questions we used microarray gene expression and TaqMan analysis to assess the gene expression profile of known oxidant-related genes in paired samples recovered by bronchoscopy from small airway epithelium and alveolar macrophages from the same healthy nonsmokers and normal smokers. Of the 155 oxidant-related genes surveyed, 122 (77%) were expressed in both cell populations in nonsmokers. However, of the genes expressed by both cell populations, oxidant related gene expression levels were higher in alveolar macrophages (67 genes, 43%) than small airway epithelium (37 genes, 24%). There were more oxidant-related genes uniquely expressed in the small airway epithelium (17%), than in alveolar macrophages (5%). In healthy smokers, the majority of oxidant-related genes were expressed in both cell populations, but there were marked differences in the numbers of oxidant-related genes that smoking up- or down-regulated. While smoking up-regulated 15 genes (10%) and down-regulated 7 genes (5%) in the small airway epithelium, smoking had far less effect on alveolar macrophages [only 4 (3%) genes up-regulated, and only 1 (0.6%) down-regulated]. Only a small number of smoking responsive oxidant-related genes overlapped between the two cell types (2 up-regulated, and no down-regulated genes). Consistent with this observation, pathway analysis of smoking-responsive genes in the small airway epithelium showed oxidant-related pathways dominated, but in alveolar macrophages immune-response pathways dominated. Thus, the responses of the oxidant-related transcriptome of cells with an identical genome and exposed to the same oxidant stress of cigarette smoking are very different, with responses of oxidant-related genes of alveolar macrophages far more subdued than that of small airway epithelium, consistent with the clinical observation that, while the small airway epithelium is vulnerable, alveolar macrophages are not "diseased" in response to the oxidant stress of cigarette smoking. Gene expression profiles of known oxidant-related genes in paired samples recovered by bronchoscopy from small airway epithelium and alveolar macrophages from the same healthy nonsmokers and normal smokers.
2011-09-11 | E-GEOD-13931 | biostudies-arrayexpress
Project description:Disparate Oxidant-related Gene Expression of Human Small Airway Epithelium Compared to Autologous Alveolar Macrophages in Response to the In Vivo Oxidant Stress of Cigarette Smoking The oxidant burden of cigarette smoking induces lung cell dysfunction, and play a significant role in the pathogenesis of lung disease. Two cell populations directly exposed to the oxidants in cigarette smoke are the small airway epithelium and alveolar macrophages. Of these, the epithelium appears to be more vulnerable to smoking, becoming disordered in differentiation, repair and function, while alveolar macrophages become activated, without becoming diseased. In this context, we asked: for the same individuals, what is the baseline trancriptome of oxidant-related genes in small airway epithelium compared to alveolar macrophages and do the responses of the transcriptome of these 2 cell populations differ substantially to inhaled cigarette smoke? To address these questions we used microarray gene expression and TaqMan analysis to assess the gene expression profile of known oxidant-related genes in paired samples recovered by bronchoscopy from small airway epithelium and alveolar macrophages from the same healthy nonsmokers and normal smokers. Of the 155 oxidant-related genes surveyed, 122 (77%) were expressed in both cell populations in nonsmokers. However, of the genes expressed by both cell populations, oxidant related gene expression levels were higher in alveolar macrophages (67 genes, 43%) than small airway epithelium (37 genes, 24%). There were more oxidant-related genes uniquely expressed in the small airway epithelium (17%), than in alveolar macrophages (5%). In healthy smokers, the majority of oxidant-related genes were expressed in both cell populations, but there were marked differences in the numbers of oxidant-related genes that smoking up- or down-regulated. While smoking up-regulated 15 genes (10%) and down-regulated 7 genes (5%) in the small airway epithelium, smoking had far less effect on alveolar macrophages [only 4 (3%) genes up-regulated, and only 1 (0.6%) down-regulated]. Only a small number of smoking responsive oxidant-related genes overlapped between the two cell types (2 up-regulated, and no down-regulated genes). Consistent with this observation, pathway analysis of smoking-responsive genes in the small airway epithelium showed oxidant-related pathways dominated, but in alveolar macrophages immune-response pathways dominated. Thus, the responses of the oxidant-related transcriptome of cells with an identical genome and exposed to the same oxidant stress of cigarette smoking are very different, with responses of oxidant-related genes of alveolar macrophages far more subdued than that of small airway epithelium, consistent with the clinical observation that, while the small airway epithelium is vulnerable, alveolar macrophages are not "diseased" in response to the oxidant stress of cigarette smoking.
2011-09-12 | GSE13931 | GEO
Project description:Cigarette smoking is the leading cause of the respiratory diseases collectively known as chronic obstructive pulmonary disease (COPD). While the pathogenesis of COPD is complex, there is abundant evidence that alveolar macrophages (AM) play an important role. Based on the concept that COPD is a slow-progressing disorder likely involving multiple mediators released by AM activated by cigarette smoke, the present study focuses on the identification of previously unrecognized genes that may be linked to early events in the molecular pathogenesis of COPD, as opposed to factors associated with the presence of disease. To accomplish this, microarray analysis using Affymetrix microarrays was used to carry out an unbiased survey of the differences in gene expression profiles in the AM of phenotypically normal, ~20 pack-yr smokers compared to healthy non-smokers. Although smoking did not alter the global gene expression pattern of AM, 75 genes were modulated by smoking, with 40 genes up-regulated and 35 down-regulated in the AM of smokers compared to non-smokers. Most of these genes belong to the functional categories of immune/inflammatory response, cell adhesion and extracellular matrix, proteolysis and antiproteolysis, lysosomal function, antioxidant-related, signal transduction and regulation of transcription. Of these 75 genes, 69 have not been previously recognized to be up- or down-regulated in alveolar macrophages in association with smoking or COPD, including genes coding for proteins belonging to all of the above categories, and others belonging to various functional categories or of unknown function. These observations suggest that gene expression responses of alveolar macrophages associated with the stress of cigarette smoking are more complex than previously thought, and offer a variety of new insights into the complex pathogenesis of smoking-induced lung diseases. Keywords: Comparison of gene expression profile in smokers vs non-smokers
2005-09-26 | GSE3212 | GEO
Project description:Lectins are innate immune defense proteins that recognize bacterial cell wall components. Based on the knowledge that cigarette smoking is associated with an increased risk of infections, we hypothesized that cigarette smoking may modulate the expression of lectin genes in airway epithelium. Affymetrix microarrays were used to survey the expression of lectin genes in large airway epithelium from nine nonsmokers and 20 healthy smokers and in small airway epithelium from 13 nonsmokers and 20 healthy smokers. There were no changes (>2-fold change; p < 0.05) in lectin gene expression among healthy smokers compared with nonsmokers except for down-regulation of intelectin 1, a lectin that binds to galactofuranosyl residues in bacterial cell walls (large airway epithelium, p < 0.01; small airway epithelium, p < 0.01). This was confirmed by TaqMan RT-PCR in both large (p < 0.05) and small airway epithelium (p < 0.02). Immunohistochemistry assessment of airway biopsies demonstrated that intelectin 1 was expressed in secretory cells, while Western analysis confirmed the decreased expression of intelectin 1 in airway epithelium of healthy smokers compared with healthy nonsmokers (p < 0.02). Finally, compared with healthy nonsmokers, intelectin 1 expression was also decreased in small airway epithelium of smokers with lone emphysema and normal spirometry (n = 13, p < 0.01) and smokers with established chronic obstructive pulmonary disease (n = 14, p < 0.01). In the context that intelectin 1 plays a role in defense against bacteria, its down-regulation in response to cigarette smoking is another example of the immunomodulatory effects of smoking on the immune system and may contribute to the increase in susceptibility to infections observed in smokers.
| S-EPMC2651682 | biostudies-literature
Project description:The tissue-resident macrophages of barrier organs constitute the first line of defence against pathogens at the systemic interface with the ambient environment. In the lung, resident alveolar macrophages (AMs) provide a sentinel function against inhaled pathogens. Bacterial constituents ligate Toll-like receptors (TLRs) on AMs, causing AMs to secrete proinflammatory cytokines that activate alveolar epithelial receptors, leading to recruitment of neutrophils that engulf pathogens. Because the AM-induced response could itself cause tissue injury, it is unclear how AMs modulate the response to prevent injury. Here, using real-time alveolar imaging in situ, we show that a subset of AMs attached to the alveolar wall form connexin 43 (Cx43)-containing gap junction channels with the epithelium. During lipopolysaccharide-induced inflammation, the AMs remained sessile and attached to the alveoli, and they established intercommunication through synchronized Ca(2+) waves, using the epithelium as the conducting pathway. The intercommunication was immunosuppressive, involving Ca(2+)-dependent activation of Akt, because AM-specific knockout of Cx43 enhanced alveolar neutrophil recruitment and secretion of proinflammatory cytokines in the bronchoalveolar lavage. A picture emerges of a novel immunomodulatory process in which a subset of alveolus-attached AMs intercommunicates immunosuppressive signals to reduce endotoxin-induced lung inflammation.
| S-EPMC4117212 | biostudies-literature
Project description:The earliest morphologic evidence of changes in the airways associated with chronic cigarette smoking is in the small airways. To help understand how smoking modifies small airway structure and function, we developed a strategy using fiberoptic bronchoscopy and brushing to sample the human small airway (10th-12th order) bronchial epithelium to assess gene expression (Affymetrix HG-U133A array) in phenotypically normal smokers (n=6, 24 ± 4 pack-yr) compared to matched non-smokers (n=5). Compared to samples from the large (2nd to 3rd order) bronchi, the small airway samples had a higher proportion of ciliated cells, but less basal, undifferentiated, and secretory cells. The small, but not large, airway samples included Clara cells, a cell found only in the small airway epithelium, and the small, but not the large, airway epithelium expressed genes for the surfactant apoproteins. Despite the fact that the smokers were phenotypically normal, analysis of the small airway epithelium of the smokers compared to the non-smokers demonstrated up- and -down-regulation of genes in multiple categories relevant to the pathogenesis of chronic obstructive lung disease (COPD), including genes coding for cytokines/innate immunity, apoptosis, pro-fibrosis, mucin, responses to oxidants and xenobiotics, antiproteases and general cellular processes. In the context that COPD starts in the small airways, these changes in gene expression in the small airway epithelium in phenotypically normal smokers are candidates for the development of therapeutic strategies to prevent the onset of COPD. Keywords: response to cigarette smoking
2005-10-30 | GSE3320 | GEO
Project description:Lectins are proteins present on cell surfaces or as shed extracellular proteins that function in innate immune defense as phagocytic receptors to recognize specific bacterial cell wall components. Based on the knowledge that cigarette smoking is associated with increased risk of bacterial infection, we hypothesized that cigarette smoking may modulate the expression of lectin genes in the airway epithelium. Affymetrix HG U133 Plus 2.0 microarrays were used to survey expression of lectin genes in large (3rd to 4th order bronchi) airway epithelium from 9 normal nonsmokers and 20 phenotypic normal smokers and small (10th to 12th order bronchi) airway epithelium from 13 normal nonsmokers and 20 phenotypic normal smokers. From the 72 lectin genes that were surveyed, there were no changes (>2-fold change, p<0.05) in gene expression in either large or small airway epithelium among normal smokers compared to nonsmokers except for a striking down regulation in both large and small airway epithelium of normal smokers of intelectin 1, a recently described lectin that participates in the innate immune response by recognizing and binding to galactofuranosyl residues in the cell walls of bacteria (large airway epithelium, p<0.003; small airway epithelium, p<0.002). TaqMan RT-PCR confirmed the observation that intelectin 1 was down-regulated in both large (p<0.05) and small airway epithelium (p<0.02) of normal smokers compared to normal nonsmokers. Immunohistochemistry assessment of biopsies of the large airway epithelium of normal nonsmokers demonstrated intelectin 1 was expressed in secretory cells, with qualitatively decreased expression in biopsies from normal smokers. Western analysis confirmed the decreased expression of intelectin 1 in airway epithelium of normal smokers compared to normal nonsmokers (p<0.02). Finally, compared to normal nonsmokers, intelectin 1 expression was decreased in small airway epithelium of smokers with early COPD (n= 13, p<0.001) and smokers with established COPD (n= 14, p<0.001), in a fashion similar to that of normal smokers. In the context that intelectin 1 is an epithelial molecule that likely plays a role in defense against bacteria, the down regulation of expression of intelectin 1 in response to cigarette smoking may contribute to the increase in susceptibility to infections observed in smokers, including those with COPD. Keywords: COPD
2008-12-19 | GSE10006 | GEO
Project description:Prior microarray studies of smokers at high risk for lung cancer have demonstrated that heterogeneity in bronchial airway epithelial cell gene expression response to smoking can serve as an early diagnostic biomarker for lung cancer. As a first step in applying functional genomic analysis to population studies, we have examined the relationship between gene expression variation and genetic variation in a central molecular pathway (NRF2-mediated antioxidant response) associated with smoking exposure and lung cancer. We assessed global gene expression in histologically normal airway epithelial cells obtained at bronchoscopy from smokers who developed lung cancer (SC, n = 20), smokers without lung cancer (SNC, n = 24), and never smokers (NS, n = 8). Functional enrichment analysis showed that the NRF2-mediated, antioxidant response element (ARE)-regulated genes, were significantly lower in SC, when compared with expression levels in SNC. Importantly, we found that the expression of MAFG (a binding partner of NRF2) was correlated with the expression of ARE genes, suggesting MAFG levels may limit target gene induction. Bioinformatically we identified single nucleotide polymorphisms (SNPs) in putative ARE genes and to test the impact of genetic variation, we genotyped these putative regulatory SNPs and other tag SNPs in selected NRF2 pathway genes. Sequencing MAFG locus, we identified 30 novel SNPs and two were associated with either gene expression or lung cancer status among smokers. This work demonstrates an analysis approach that integrates bioinformatics pathway and transcription factor binding site analysis with genotype, gene expression and disease status to identify SNPs that may be associated with individual differences in gene expression and/or cancer status in smokers. These polymorphisms might ultimately contribute to lung cancer risk via their effect on the airway gene expression response to tobacco-smoke exposure.
| S-EPMC2914741 | biostudies-literature
Project description:The earliest morphologic evidence of changes in the airways associated with chronic cigarette smoking is in the small airways. To help understand how smoking modifies small airway structure and function, we developed a strategy using fiberoptic bronchoscopy and brushing to sample the human small airway (10th-12th order) bronchial epithelium to assess gene expression (Affymetrix HG-U133A array) in phenotypically normal smokers (n=6, 24 ± 4 pack-yr) compared to matched non-smokers (n=5). Compared to samples from the large (2nd to 3rd order) bronchi, the small airway samples had a higher proportion of ciliated cells, but less basal, undifferentiated, and secretory cells. The small, but not large, airway samples included Clara cells, a cell found only in the small airway epithelium, and the small, but not the large, airway epithelium expressed genes for the surfactant apoproteins. Despite the fact that the smokers were phenotypically normal, analysis of the small airway epithelium of the smokers compared to the non-smokers demonstrated up- and -down-regulation of genes in multiple categories relevant to the pathogenesis of chronic obstructive lung disease (COPD), including genes coding for cytokines/innate immunity, apoptosis, pro-fibrosis, mucin, responses to oxidants and xenobiotics, antiproteases and general cellular processes. In the context that COPD starts in the small airways, these changes in gene expression in the small airway epithelium in phenotypically normal smokers are candidates for the development of therapeutic strategies to prevent the onset of COPD. Experiment Overall Design: 6 smokers Experiment Overall Design: 5 non-smokers Experiment Overall Design: no replicates
2007-09-06 | E-GEOD-3320 | biostudies-arrayexpress
Project description:Lectins are proteins present on cell surfaces or as shed extracellular proteins that function in innate immune defense as phagocytic receptors to recognize specific bacterial cell wall components. Based on the knowledge that cigarette smoking is associated with increased risk of bacterial infection, we hypothesized that cigarette smoking may modulate the expression of lectin genes in the airway epithelium. Affymetrix HG U133 Plus 2.0 microarrays were used to survey expression of lectin genes in large (3rd to 4th order bronchi) airway epithelium from 9 normal nonsmokers and 20 phenotypic normal smokers and small (10th to 12th order bronchi) airway epithelium from 13 normal nonsmokers and 20 phenotypic normal smokers. From the 72 lectin genes that were surveyed, there were no changes (>2-fold change, p<0.05) in gene expression in either large or small airway epithelium among normal smokers compared to nonsmokers except for a striking down regulation in both large and small airway epithelium of normal smokers of intelectin 1, a recently described lectin that participates in the innate immune response by recognizing and binding to galactofuranosyl residues in the cell walls of bacteria (large airway epithelium, p<0.003; small airway epithelium, p<0.002). TaqMan RT-PCR confirmed the observation that intelectin 1 was down-regulated in both large (p<0.05) and small airway epithelium (p<0.02) of normal smokers compared to normal nonsmokers. Immunohistochemistry assessment of biopsies of the large airway epithelium of normal nonsmokers demonstrated intelectin 1 was expressed in secretory cells, with qualitatively decreased expression in biopsies from normal smokers. Western analysis confirmed the decreased expression of intelectin 1 in airway epithelium of normal smokers compared to normal nonsmokers (p<0.02). Finally, compared to normal nonsmokers, intelectin 1 expression was decreased in small airway epithelium of smokers with early COPD (n= 13, p<0.001) and smokers with established COPD (n= 14, p<0.001), in a fashion similar to that of normal smokers. In the context that intelectin 1 is an epithelial molecule that likely plays a role in defense against bacteria, the down regulation of expression of intelectin 1 in response to cigarette smoking may contribute to the increase in susceptibility to infections observed in smokers, including those with COPD. Keywords: COPD Comparison of gene expression in airway epithelial cells of normal non-smokers, phenotypic normal smokers, smokers with early COPD, and smokers with COPD.
2008-12-19 | E-GEOD-10006 | biostudies-arrayexpress