Project description:To identify transcriptomic signature of human airway epithelium as it undergoes full differentiation into mucociliated epithelial cells under air-liquid interface. We used microarrays to detail the global gene expression pattern from day 0 through day 28 following air-liquid interface in human airway epithelial cells and identified distinct clusters of gene expression during this process.
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 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. Four time points (ALI-D0, ALI-D7, ALI-D14, ALI-D21) of regeneration of the airway epithelium for 3 donors.
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:In the process of seeking novel lung host defense regulators by analyzing genome-wide RNA sequence data from normal human airway epithelium, we detected expression of POU2AF1, a known transcription co-factor previously thought to be expressed only in lymphocytes. Lymphocyte contamination of human airway epithelial samples obtained by bronchoscopy and brushing was excluded by immunohistochemistry staining, the observation of up-regulation of POU2AF1 in purified airway basal stem/progenitor cells undergoing differentiation and analysis of differentiating single basal cell clones. Lentivirus-mediated up-regulation of POU2AF1 in airway basal cells induced up-regulation of host defense genes, including MX1, IFIT3, IFITM and known POU2AF1 downstream genes HLA-DRA, ID2, ID3, IL6, BCL6. Interestingly, expression of these genes paralleled changes of POU2AF1 expression during airway epithelium differentiation in vitro, suggesting POU2AF1 helps to maintain a "host defense tone" even in pathogen-free condition. Cigarette smoke, a known risk factor for airway infection, suppressed POU2AF1 expression both in vivo in humans and in vitro in human airway epithelial cultures, accompanied by deregulation of POU2AF1 downstream genes. Finally, enhancing POU2AF1 expression in human airway epithelium attenuated the suppression of host defense genes by smoking. Together, these findings suggest a novel function of POU2AF1 as a potential regulator of host defense genes in the human airway epithelium. Methods: Massive parallel RNA sequencing was used to compare the transcriptome of lentivirus mediated POU2AF1 or RFP (control) gene expression in human primary airway epithelial cells (3 samples per group). Uninfected basal cell was used as a further control. Conclusions: The genes up-regulated by POU2AF1 in human airway epithelial cells are mainly related to the intracellular or extracellular anti-pathogen response, suggesting POU2AF1 plays a role in airway epithelial host defense. This Series represents samples complementary to those in GSE60989.
Project description:Despite being exposed to respiratory syncytial virus (RSV) infection multiple times in our lives, infants, older-adults, and immunocompromised patients are vulnerable to RSV-associated severe diseases, such as bronchiolitis and pneumonia. Respiratory viral infections are known to promote pulmonary fibrosis formation, which are often associated with a cellular remodeling process epithelial-mesenchymal transition (EMT). However, there is no information on whether RSV causes EMT in bronchial epithelial cells. Our results suggest that RSV-infection does not induce EMT in three different in vitro lung models: epithelial A549 cell line, primary normal human bronchial epithelial cells, and pseudostratified airway epithelium. Interestingly, RSV infection increased cell surface area and perimeter in the infected airway epithelium, which is distinct from the TGF-β1 driven cell elongation. Genome-wide transcriptome analysis also revealed that RSV infection is not involved in cell motility and locomotion. Thus, our results suggest that RSV infection does not induce EMT in the airway epithelium
Project description:Modification of Gene Expression of the Small Airway Epithelium in Response to Cigarette Smoking 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 (HG-133 Plus 2.0 array) in phenotypically normal smokers (n=10, 33 ± 7 pack-yr) compared to matched non-smokers (n=12). Even though 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, mucin, response to oxidants and xenobiotics, and general cellular processes. In the context that COPD starts in the small airways, these gene expression changes in the small airway epithelium in phenotypically normal smokers are candidates for the development of therapeutic strategies to prevent the onset of COPD. Keywords: smokers vs non-smokers