Project description:Human airway epithelial cells cultured in vitro at air-liquid interface (ALI) form a pseudostratified epithelium that forms tight junctions and cilia, and produces mucin, and are widely used as a model of differentiation, injury, and repair. To assess how closely the transcriptome of ALI epithelium matches that of in vivo airway epithelial cells, we used microarrays to compare the transcriptome of human large airway epithelial cells cultured at ALI with the transcriptome of large airway epithelium obtained via bronchoscopy and brushing. Gene expression profiling showed global gene expression correlated well between ALI cells and brushed cells, but there were some differences. Gene expression patterns mirrored differences in proportions of cell types (ALI have higher percentages of basal cells, brushed cells have higher percentages of ciliated cells), with ALI cells expressing higher levels of basal cell-related genes and brushed cells expressing higher levels of cilia-related genes. Pathway analysis showed ALI cells had increased expression of cell cycle and proliferation genes, while brushed cells had increased expression of cytoskeletal organization and humoral immune response genes. Overall, ALI cells are a good representation of the in vivo airway epithelial transcriptome, but for some biologic questions, the differences in the in vitro vs in vivo environments need to be considered. Affymetrix arrays were used to assess the gene expression of large airway cells cultured in vitro at air-liquid interface (12 samples) and large airway epithelial cells obtained by fiberoptic bronchoscopy of 20 healthy nonsmokers. *** Air-liquid interface Samples not provided in this Series. ***
Project description:The unsurpassed simplicity of the fruitflyâs airway epithelium, that is made of homogenous epithelial cells only, favours its use as a model to study general features and response characteristics of airway epithelia in general. All epithelial cells are able to launch an immune response as characterized by the expression of antimicrobial peptide genes. Infection induces a complex change in the expression profile of these epithelial cells. Outstanding are a priming of the immune system and the launch of a survival program, presumably to counteract infection induced apoptotic signals, which comprises the concurrent expression of known longevity genes such as dFoxo, and dThor. In regions of the airway epithelium with strong immune reactions, a complex remodelling of the airways can be observed, which is characterized by metaplasia and presumably also by hyperplasia of the affected epithelial cells. At the transcriptional level, this reorganization of the airway epithelium is mirrored by a recapitulation of genetic programs that are characteristic for early phases of airway development. Taken together, the response characteristics of the flyâs airway epithelium towards infections discloses features that are known from inflammatory diseases of the human lung, thus opening the opportunity to study fundamental aspects of these diseases in the fly. Keywords:infection, Erwinia c., third instar larva, airway epithelium, two-colour microarray Infection of the airway epithelium by the gram-negativ bacteria Erwinia carotovora. For the infection experiments third instar larvae of the GFP-reporter strain YW DD1 were used and only isolated when the whole epithelium of the airway epithelium showed GFP expression. Uninfected larvae were used as controls. In general, four replicates were performed including dye-swaps. A table of significantly-regulated genes from the SAM-output and GeneTraffic-output has been linked as a supplementary file at the foot of this record.
Project description:Human airway epithelial cells cultured in vitro at air-liquid interface (ALI) form a pseudostratified epithelium that forms tight junctions and cilia, and produces mucin, and are widely used as a model of differentiation, injury, and repair. To assess how closely the transcriptome of ALI epithelium matches that of in vivo airway epithelial cells, we used microarrays to compare the transcriptome of human large airway epithelial cells cultured at ALI with the transcriptome of large airway epithelium obtained via bronchoscopy and brushing. Gene expression profiling showed global gene expression correlated well between ALI cells and brushed cells, but there were some differences. Gene expression patterns mirrored differences in proportions of cell types (ALI have higher percentages of basal cells, brushed cells have higher percentages of ciliated cells), with ALI cells expressing higher levels of basal cell-related genes and brushed cells expressing higher levels of cilia-related genes. Pathway analysis showed ALI cells had increased expression of cell cycle and proliferation genes, while brushed cells had increased expression of cytoskeletal organization and humoral immune response genes. Overall, ALI cells are a good representation of the in vivo airway epithelial transcriptome, but for some biologic questions, the differences in the in vitro vs in vivo environments need to be considered.
Project description:The unsurpassed simplicity of the fruitfly’s airway epithelium, that is made of homogenous epithelial cells only, favours its use as a model to study general features and response characteristics of airway epithelia in general. All epithelial cells are able to launch an immune response as characterized by the expression of antimicrobial peptide genes. Infection induces a complex change in the expression profile of these epithelial cells. Outstanding are a priming of the immune system and the launch of a survival program, presumably to counteract infection induced apoptotic signals, which comprises the concurrent expression of known longevity genes such as dFoxo, and dThor. In regions of the airway epithelium with strong immune reactions, a complex remodelling of the airways can be observed, which is characterized by metaplasia and presumably also by hyperplasia of the affected epithelial cells. At the transcriptional level, this reorganization of the airway epithelium is mirrored by a recapitulation of genetic programs that are characteristic for early phases of airway development. Taken together, the response characteristics of the fly’s airway epithelium towards infections discloses features that are known from inflammatory diseases of the human lung, thus opening the opportunity to study fundamental aspects of these diseases in the fly. Keywords:infection, Erwinia c., third instar larva, airway epithelium, two-colour microarray
Project description:Field of cancerization in the airway epithelium has been increasing examined to understand early pathogenesis of non-small cell lung cancer. This study uses microarray high-throughput technologies to characterize the molecular aberrations in the terminal airway and bronchoalveolar cells in the context of field cancerization in high-risk smokers and lung cancer patients. We collected peripheral airway brushings from the contral-lateral lung of the tumor from cancer patients (n=17) and smoker controls (n=13); Total RNA were obtained from the peripheral airway epithelium.
Project description:Field of cancerization in the airway epithelium has been increasing examined to understand early pathogenesis of non-small cell lung cancer. This study uses microarray high-throughput technologies to characterize the molecular aberrations in the terminal airway and bronchoalveolar cells in the context of field cancerization in high-risk smokers and lung cancer patients. We collected peripheral airway brushings from the contral-lateral lung of the tumor from cancer patients (n=17) and smoker controls (n=13); Total RNA were obtained from the peripheral airway epithelium.
Project description:The regeneration of the airway mucociliary epithelium involves several sequential events including migration, proliferation, polarization and final differentiation (i.e ciliogenesis). The airway mucociliary epithelium is consituted of three main cell types : ciliated cells, secretory cells and basal cells. We used microRNA microrrays to investigate the signature of microRNA during the four step of regeneration of the airway epithelium.