Transcriptome in alveolar epithelial progenitor cells isolated from adult human lung
Ontology highlight
ABSTRACT: Resident stem/progenitor cells in the lung are important for tissue homeostasis and repair. However, a progenitor population for alveolar type II (ATII) cells in adult human lungs have not been identified. Here we isolated alveolar epithelial progenitor cells (AEPCs) from adult human lungs. AEPCs showed mesenchymal stem cell (MSC)-like characteristics combined with ATII cell-phenotypes. AEPCs had the capability for self-renewal and the potential to generate ATII cells in vitro. Furthermore, cells expressing similar markers were present within alveolar walls in normal lungs and these cells were significantly increased in ATII cell hyperplasias. These results suggest that adult human lungs contain a progenitor population for ATII cells.
Project description:Resident stem/progenitor cells in lungs are important for tissue homeostasis and repair. We isolated human lung progenitor cells and named alveolar epithelial progenitor cells (AEPCs)(Fujino N, et al. 2011. Lab Invest. 91:363). AEPCs have phenotypes of both alveolar epithelial type II (ATII) cells and mesenchymal stem cells. AEPCs had the potential to generate ATII-like cells in vitro. ATII-like cells derived from AEPCs expressed protein and mRNA of pulmonary surfactant, and displayed lamellar bodies containing the surfactants. However, it has not been evaluated whether global gene expression of the ATII-like cells from AEPCs was similar to that of mature ATII cells isolated from human lung tissues. This study demonstrated gene expression profiles of ATII-like cells from AEPCs. In addition, transcriptomes in AEPCs and mature ATII cells were deposited in the GEO website (GSE21095 and GSE29133, respectively).
Project description:Resident stem/progenitor cells in lungs are important for tissue homeostasis and repair. We isolated human lung progenitor cells and named alveolar epithelial progenitor cells (AEPCs)(Fujino N, et al. 2011. Lab Invest. 91:363). AEPCs have phenotypes of both alveolar epithelial type II (ATII) cells and mesenchymal stem cells. AEPCs had the potential to generate ATII-like cells in vitro. ATII-like cells derived from AEPCs expressed protein and mRNA of pulmonary surfactant, and displayed lamellar bodies containing the surfactants. However, it has not been evaluated whether global gene expression of the ATII-like cells from AEPCs was similar to that of mature ATII cells isolated from human lung tissues. This study demonstrated gene expression profiles of ATII-like cells from AEPCs. In addition, transcriptomes in AEPCs and mature ATII cells were deposited in the GEO website (GSE21095 and GSE29133, respectively). We isolated AEPCs from tissue samples obtained from patients who underwent lung resection at Department of Thoracic Surgery, Tohoku University Hospital. We induced differentiation of AEPCs to ATII-like cells on extracellular matrix with medium containing KGF, cAMP and IBMX, as previously described (Fujino N, et al. 2011. Lab Invest. 91:363). We profiled the gene expression in three different batches of the ATII-like cells. We extracted total RNA from the differentiated cells. This study was approved by the Ethics Committee at Tohoku University School of Medicine. All subjects gave informed consent.
Project description:Alveolar epithelial type II (ATII) cells play a critical role in homeostasis and repair process of the lungs. In lung diseases such as chronic obstructive pulmonary disease (COPD), ATII cells are damaged and fall into apoptosis or senescence. Until to date, global gene expression of ATII cells in COPD lungs has not been analyzed. We isolated ATII cells from three non-COPD and three COPD patients using a FACS method. Then, we performed microarray analysis to compare gene expression profiles of ATII cells between non-COPD and COPD patients.
Project description:Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, irreversible, and lethal lung disease. The initiation of IPF involves microinjuries to and/or dysfunction of the alveolar epithelium, but factors that determine fibrosis progression or normal tissue repair are largely unknown. We previously demonstrated that autophagy inhibition-mediated epithelial-mesenchymal transition (EMT) in human alveolar epithelial type II (ATII) cells augments local myofibroblast differentiation in pulmonary fibrosis by paracrine signalling. Here, we report that liver kinase B1 (LKB1) inactivation in ATII cells induces autophagy inhibition and EMT as a consequence. In IPF lungs, this is caused by a downregulation of CAB39L, a key subunit within the LKB1 complex. 3D co-cultures of ATII cells and lung fibroblast MRC5 coupled with RNA sequencing (RNA-seq) confirmed that paracrine signalling between LKB1-depleted ATII cells and fibroblasts augmented myofibroblast differentiation. Together these data suggest that reduced autophagy caused by LKB1 inhibition can induce EMT in ATII cells and contribute to fibrosis via aberrant epithelial–fibroblast crosstalk.
Project description:Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, irreversible, and lethal lung disease. The initiation of IPF involves microinjuries to and/or dysfunction of the alveolar epithelium, but factors that determine fibrosis progression or normal tissue repair are largely unknown. We previously demonstrated that autophagy inhibition-mediated epithelial-mesenchymal transition (EMT) in human alveolar epithelial type II (ATII) cells augments local myofibroblast differentiation in pulmonary fibrosis by paracrine signalling. Here, we report that liver kinase B1 (LKB1) inactivation in ATII cells induces autophagy inhibition and EMT as a consequence. In IPF lungs, this is caused by a downregulation of CAB39L, a key subunit within the LKB1 complex. 3D co-cultures of ATII cells and lung fibroblast MRC5 coupled with RNA sequencing (RNA-seq) confirmed that paracrine signalling between LKB1-depleted ATII cells and fibroblasts augmented myofibroblast differentiation. Together these data suggest that reduced autophagy caused by LKB1 inhibition can induce EMT in ATII cells and contribute to fibrosis via aberrant epithelial–fibroblast crosstalk.
Project description:Alveolar epithelial type II (ATII)-like cells can be generated from murine embryonic stem cells (ESCs), although to date, no robust protocols applying specific differentiation factors are established. We hypothesized that the keratinocyte growth factor (KGF), an important mediator of lung organogenesis and primary ATII cell maturation and proliferation, together with dexamethasone, 8-bromoadenosine-cAMP, and isobutylmethylxanthine (DCI), which induce maturation of primary fetal ATII cells, also support the alveolar differentiation of murine ESCs. Here we demonstrate that the above stimuli synergistically potentiate the alveolar differentiation of ESCs as indicated by increased expression of the surfactant proteins (SP-) C and SP-B. This effect is most profound if KGF is supplied not only in the late stage, but at least also during the intermediate stage of differentiation. Our results indicate that KGF most likely does not enhance the generation of (mes)endodermal or NK2 homeobox 1 (Nkx2.1) expressing progenitor cells but rather, supported by DCI, accelerates further differentiation/maturation of respiratory progeny in the intermediate phase and maturation/proliferation of emerging ATII cells in the late stage of differentiation. Ultrastructural analyses confirmed the presence of ATII-like cells with intracellular composite and lamellar bodies. Finally, induced pluripotent stem cells (iPSCs) were generated from transgenic mice with ATII cell-specific lacZ reporter expression. Again, KGF and DCI synergistically increased SP-C and SP-B expression in iPSC cultures, and lacZ expressing ATII-like cells developed. In conclusion, ATII cell-specific reporter expression enabled the first reliable proof for the generation of murine iPSC-derived ATII cells. In addition, we have shown KGF and DCI to synergistically support the generation of ATII-like cells from ESCs and iPSCs. Combined application of these factors will facilitate more efficient generation of stem cell-derived ATII cells for future basic research and potential therapeutic application. 10 samples in total. mESCs at d8 of differentiation (Control) mESCs at d8 of differentiation with KGF treatment mESCs at d17 of differentiation (Control) mESCs at d17 of differentiation with KGF treatment mESCs at d17 of differentiation with DCI treatment mESCs at d17 of differentiation with KGF and DCI treatment mESCs at d24 of differentiation (Control) mESCs at d24 of differentiation with KGF treatment mESCs at d24 of differentiation with DCI treatment mESCs at d24 of differentiation with KGF and DCI treatment
Project description:We performed single cell RNA sequencing of CD45-negative cells sorted from WT and p47phox-KI lungs with ALI to characterize the impacts of the loss of p47phox phosphorylation in blood cells on pulmonary endothelial and epithelial cells. We found many genes are pertinent to enhancement of pulmonary vasculature integrity, maintain alveolar roles, promote ATII cell proliferation and lower oxidative stress state in p47phox-KI lungs.
Project description:Alveolar epithelial type II (ATII)-like cells can be generated from murine embryonic stem cells (ESCs), although to date, no robust protocols applying specific differentiation factors are established. We hypothesized that the keratinocyte growth factor (KGF), an important mediator of lung organogenesis and primary ATII cell maturation and proliferation, together with dexamethasone, 8-bromoadenosine-cAMP, and isobutylmethylxanthine (DCI), which induce maturation of primary fetal ATII cells, also support the alveolar differentiation of murine ESCs. Here we demonstrate that the above stimuli synergistically potentiate the alveolar differentiation of ESCs as indicated by increased expression of the surfactant proteins (SP-) C and SP-B. This effect is most profound if KGF is supplied not only in the late stage, but at least also during the intermediate stage of differentiation. Our results indicate that KGF most likely does not enhance the generation of (mes)endodermal or NK2 homeobox 1 (Nkx2.1) expressing progenitor cells but rather, supported by DCI, accelerates further differentiation/maturation of respiratory progeny in the intermediate phase and maturation/proliferation of emerging ATII cells in the late stage of differentiation. Ultrastructural analyses confirmed the presence of ATII-like cells with intracellular composite and lamellar bodies. Finally, induced pluripotent stem cells (iPSCs) were generated from transgenic mice with ATII cell-specific lacZ reporter expression. Again, KGF and DCI synergistically increased SP-C and SP-B expression in iPSC cultures, and lacZ expressing ATII-like cells developed. In conclusion, ATII cell-specific reporter expression enabled the first reliable proof for the generation of murine iPSC-derived ATII cells. In addition, we have shown KGF and DCI to synergistically support the generation of ATII-like cells from ESCs and iPSCs. Combined application of these factors will facilitate more efficient generation of stem cell-derived ATII cells for future basic research and potential therapeutic application.
Project description:Pulmonary research requires models that represent the physiology of alveolar epithelium but concerns with reproducibility, consistency and the technical and ethical challenges of using primary or stem cells has resulted in widespread use of continuous cancer or other immortalized cell lines. The A549 ‘alveolar’ cell line has been available for over four decades but there is an inconsistent view as to its suitability as an appropriate model for primary alveolar type II (ATII) cells. Since most work with A549 cells involves short term culture of proliferating cells, we postulated that culture conditions that reduced proliferation of the cancer cells would promote a more differentiated ATII cell phenotype. We examined A549 cell growth in different media over long term culture and then used microarray analysis to investigate temporal regulation of pathways involved in cell cycle and ATII differentiation; we also made comparisons with gene expression in freshly isolated human ATII cells. Analyses indicated that long term culture in Ham’s F12 resulted in substantial modulation of cell cycle genes to result in a quiescent population of cells with significant up-regulation of autophagic, differentiation and lipidogenic pathways. There were also increased numbers of up- and down-regulated genes shared with primary cells suggesting adoption of ATII characteristics and multilamellar body (MLB) development. Subsequent Oil Red-O staining and Transmission Electron Microscopy confirmed MLB expression in the differentiated A549 cells. This work defines a set of conditions for promoting ATII differentiation characteristics in A549 cells that may be advantageous for studies with this cell line.
Project description:Pulmonary research requires models that represent the physiology of alveolar epithelium but concerns with reproducibility, consistency and the technical and ethical challenges of using primary or stem cells has resulted in widespread use of continuous cancer or other immortalized cell lines. The A549 ‘alveolar’ cell line has been available for over four decades but there is an inconsistent view as to its suitability as an appropriate model for primary alveolar type II (ATII) cells. Since most work with A549 cells involves short term culture of proliferating cells, we postulated that culture conditions that reduced proliferation of the cancer cells would promote a more differentiated ATII cell phenotype. We examined A549 cell growth in different media over long term culture and then used microarray analysis to investigate temporal regulation of pathways involved in cell cycle and ATII differentiation; we also made comparisons with gene expression in freshly isolated human ATII cells. Analyses indicated that long term culture in Ham’s F12 resulted in substantial modulation of cell cycle genes to result in a quiescent population of cells with significant up-regulation of autophagic, differentiation and lipidogenic pathways. There were also increased numbers of up- and down-regulated genes shared with primary cells suggesting adoption of ATII characteristics and multilamellar body (MLB) development. Subsequent Oil Red-O staining and Transmission Electron Microscopy confirmed MLB expression in the differentiated A549 cells. This work defines a set of conditions for promoting ATII differentiation characteristics in A549 cells that may be advantageous for studies with this cell line.