Project description:We used microfluidic single cell RNA-seq on adult isolated CC10-CreERT2 (negative) integrin beta4(pos) cells lung epithelial cells in order to determine the transcriptional profile of this putative progenitor population. CC10-CreERT2 / tdTomato (negative) integrin beta4(pos) cells were isolated by FACS, as were Krt5-CreERT2 / tdTomato (positive) cells. These cells were pooled and loaded onto the Fluidigm C1 device.
Project description:We used microfluidic single cell RNA-seq on adult isolated CC10-CreERT2 (negative) integrin beta4(pos) cells lung epithelial cells in order to determine the transcriptional profile of this putative progenitor population.
Project description:Aberrant expansion of KRT5+ basal cells in the distal lung accompanies progressive alveolar epithelial cell loss and tissue remodelling during fibrogenesis in idiopathic pulmonary fibrosis (IPF). The mechanisms determining activity of KRT5+ cells in IPF have not been delineated. Here, we show an association between KRT5+ cells in human fibrotic lung and regional differences in collagen topography. In vitro, KRT5+ cell migratory characteristics and expression of remodelling genes are modulated by extracellular matrix (ECM) composition and organisation. Mass spectrometry-based proteomics revealed compositional differences in the matrisome secreted by primary human lung fibroblasts (HLF) from IPF patients compared to controls. Over-expression of ECM glycoprotein, Secreted Protein Acidic and Cysteine Rich (SPARC) in the IPF HLF matrisome restricts KRT5+ cell migration in vitro. Together, our findings demonstrate that changes to the ECM in IPF directly influence KRT5+ cell behaviour and function contributing to remodelling events in the fibrotic niche.
Project description:Transcriptome analysis of urothelial KRT5-traced and KRT8-traced YFP-sorted cells with and without combinatorial loss of Trp53 and Pten. Bladders from 2-month-old KRT5-CreERT2, Rosa26YFP/LacZ mice, 2-month-old KRT8-CreERT2, Rosa26YFP/LacZ mice, 5-month-old KRT5-CreERT2, p53flox/flox, Ptenflox/flox, Rosa26YFP/+ mice, and 5-month-old KRT8-CreERT2, p53flox/flox, Ptenflox/flox, Rosa26YFP/+ mice were enzymatically dissociated, sorted for YFP by FACS, harvested, resuspended in Trizol and snap frozen for subsequent molecular analysis.
Project description:Although mutations in Kras are present in 21% of lung tumors, there is a high level of heterogeneity in phenotype and outcomes amongst lung cancer patients suggesting the importance of other pathways. Wnt/β-catenin signaling is a known oncogenic pathway that plays a well defined role in colon and skin cancer but its role in lung cancer remains unclear. We show that activation of Wnt/β-catenin in the bronchiolar epithelium of the adult lung does not promote tumor development by itself. However, activation of Wnt/β- catenin signaling leads to a dramatic increase in tumor formation both in overall tumor number and size compared to KrasG12D alone. We show that activation of Wnt/β- catenin signaling significantly alters the KrasG12D tumor phenotype resulting in a phenotypic switch from bronchiolar epithelium to the highly proliferative distal progenitors found in the embryonic lung. This is associated with a decrease in E- cadherin expression at the cell surface which may increase metastasis in Wnt/β-catenin signaling positive tumors. Together, these data suggest that activation of Wnt/β-catenin signaling in combination with other oncogenic pathways in lung epithelium may lead to a more aggressive phenotype due to the imposition of an embryonic distal progenitor phenotype accompanied by decreased E-cadherin expression. We performed microarray analysis of control murine lung, CC10-cre:KrasG12D, and CC10-cre:Ctnnb1ex3flox:LSL-KrasG12D double mutant micro-dissected murine lung tumors to determine their transcriptional phenotype. Lungs of five-month-old mice were PBS inflated and all the tumors in each lobe were dissected. The total number of tumors obtained from three out of the 5 pulmonar lobes of each animal was called a sample the other two lobes were saved in case there were problems and the array needed to be repeated. Trizol was used to isolate RNA for microarray analysis. Samples & Genotypes: control murine lung n=2 animals, CC10-cre:KrasG12D n=2 animals, and CC10-cre:Ctnnb1ex3flox:LSL-KrasG12D n=2 animals.
Project description:The distal lung contains terminal bronchioles and alveoli that facilitate gas exchange. Three-dimensional in vitro human distal lung culture systems would strongly facilitate investigation of pathologies including interstitial lung disease, cancer, and SARS-CoV-2-associated COVID-19 pneumonia. We generated long-term feeder-free, chemically-defined culture of distal lung progenitors as organoids derived from single adult human alveolar epithelial type II (AT2) or KRT5+ basal cells. AT2 organoids exhibited AT1 transdifferentiation potential while basal cell organoids developed lumens lined by differentiated club and ciliated cells. Single cell analysis of basal organoid KRT5+ cells revealed a distinct ITGA6+ITGB4+ mitotic population whose proliferation further segregated to a TNFRSF12Ahi subfraction comprising ~10% of KRT5+ basal cells, residing in clusters within terminal bronchioles and exhibiting enriched clonogenic organoid growth activity. Distal lung organoids were created with apical-out polarity to display ACE2 on the exposed external surface, facilitating SARS-CoV-2 infection of AT2 and basal cultures and identifying club cells as a novel target population. This long-term, feeder-free organoid culture of human distal lung, coupled with single cell analysis, identifies unsuspected basal cell functional heterogeneity and establishes a facile in vitro organoid model for human distal lung infections including COVID-19-associated pneumonia.
Project description:The possibility of lung regeneration has been long discounted due to the irreversible nature of chronic lung diseases. However, patients who sustain massive loss of lung tissue during acute infections often recover full pulmonary function. Correspondingly, we previously demonstrated lung regeneration in mice following H1N1 influenza virus infection and implicated p63+Krt5+ distal airway stem cells, or DASCp63/Krt5, in this process. We show here that rare, preexisting DASCp63/K5 undergo a proliferative expansion in response to influenza and lineage-trace to nascent alveoli assembled at sites of interstitial inflammation. We also show that the ablation of DASCp63/Krt5 in vivo prevents the regeneration of lung tissue following influenza leading to pre-fibrotic lesions and deficient oxygen exchange. Finally, we demonstrate that exogenously cloned and propagated DASCp63/Krt5 readily contribute to lung regeneration following transplantation. The transplanted DASC ameliorated influenza-induced lung injury. These data suggest that DASCp63/K5 are required for lung regeneration and may have therapeutic utility in acute and chronic lung diseases. Transplanted DASC cells incorporated into damaged host lung were laser capture microdissected and analyzed. Duplicate mice were included. We used the Affymetrix Mouse Exon 1.0 ST platform
Project description:The possibility of lung regeneration has been long discounted due to the irreversible nature of chronic lung diseases. However, patients who sustain massive loss of lung tissue during acute infections often recover full pulmonary function. Correspondingly, we previously demonstrated lung regeneration in mice following H1N1 influenza virus infection and implicated p63+Krt5+ distal airway stem cells, or DASCp63/Krt5, in this process. We show here that rare, preexisting DASCp63/K5 undergo a proliferative expansion in response to influenza and lineage-trace to nascent alveoli assembled at sites of interstitial inflammation. We also show that the ablation of DASCp63/Krt5 in vivo prevents the regeneration of lung tissue following influenza leading to pre-fibrotic lesions and deficient oxygen exchange. Finally, we demonstrate that exogenously cloned and propagated DASCp63/Krt5 readily contribute to lung regeneration following transplantation. The transplanted DASC ameliorated influenza-induced lung injury. These data suggest that DASCp63/K5 are required for lung regeneration and may have therapeutic utility in acute and chronic lung diseases. DASC stem cells were ablated by Dtox treatment in Krt6:DTR mouse model. Control and stem cell ablated lungs were analyzed. We used the Affymetrix Mouse Exon 1.0 ST platform
Project description:The possibility of lung regeneration has been long discounted due to the irreversible nature of chronic lung diseases. However, patients who sustain massive loss of lung tissue during acute infections often recover full pulmonary function. Correspondingly, we previously demonstrated lung regeneration in mice following H1N1 influenza virus infection and implicated p63+Krt5+ distal airway stem cells, or DASCp63/Krt5, in this process. We show here that rare, preexisting DASCp63/K5 undergo a proliferative expansion in response to influenza and lineage-trace to nascent alveoli assembled at sites of interstitial inflammation. We also show that the ablation of DASCp63/Krt5 in vivo prevents the regeneration of lung tissue following influenza leading to pre-fibrotic lesions and deficient oxygen exchange. Finally, we demonstrate that exogenously cloned and propagated DASCp63/Krt5 readily contribute to lung regeneration following transplantation. The transplanted DASC ameliorated influenza-induced lung injury. These data suggest that DASCp63/K5 are required for lung regeneration and may have therapeutic utility in acute and chronic lung diseases. Stem cells before and after in vitro differentiation were subjected to whole genome microarray analysis. Duplicates were included for each sample. We used the Affymetrix Mouse Exon 1.0 ST platform