Project description:Mechanisms of epithelial renewal in the alveolar compartment remain incompletely understood. To this end, we aimed to characterize alveolar progenitors. Single-cell RNA-seq (scRNA-seq) analysis of the HTII-280 positive and HTII-280+ /EpCAM+populations from total 6 donors from periferal tissue was performed, and analysis revealed subclusters enriched for stem cell signature genes. We found that these alveolar progenitors in organoid culture in vitro show phenotypic lineage plasticity as they can yield alveolar or bronchial cell type progeny. The direction of the differentiation is dependent on the presence of the GSK-3β inhibitor, CHIR99021. By RNA-seq analysis of GSK-3 βknockdown organoids, we identify additional functional candidate target genes and pathways which contribute to alveolar differentiation independent of Wnt signaling
Project description:Mechanisms of epithelial renewal in the alveolar compartment remain incompletely understood. To this end, we aimed to characterize alveolar progenitors. Single-cell RNA-sequencing (scRNA-seq) analysis of the HTII-280+/EpCAM+ population from adult human lung revealed subclusters enriched for adult stem cell signature (ASCS) genes. We found that alveolar progenitors in organoid culture in vitro show phenotypic lineage plasticity as they can yield alveolar or bronchial cell-type progeny. The direction of the differentiation is dependent on the presence of the GSK-3β inhibitor, CHIR99021. By RNA-seq profiling of GSK-3β knockdown organoids we identified additional candidate target genes of the inhibitor, among others FOXM1 and EGF. This gives evidence of Wnt pathway independent regulatory mechanisms of alveolar specification. Following influenza A virus (IAV) infection organoids showed a similar response as lung tissue explants which confirms their suitability for studies of sequelae of pathogen-host interaction.
Project description:Lung injury activates potential stem cells or progenitors for alveolar repair and regeneration. However, the activation program and source of injury-induced facultative progenitors remain incompletely known. Here, we find that lung injury induces emergence of p63-expressing progenitors, which rapidly proliferate and differentiate into alveolar type-1 (AT1) and type-2 (AT2) cells. scRNA-seq analysis uncovers that a subset of p63+ progenitors exhibit two distinct parallele transient stages before differentiation into mature AT1 and AT2 cells, respectively. Dual recombinases-mediated sequential genetic tracing reveals that facultative p63+ progenitors originate from the distal airway secretory cells and subsequently regenerate alveoli. Functioanlly, secretory cell-specific knockout of p63 significantly impairs their contribution to alveolar epithelium during lung regeneration. Our study identified secretory cell-derived facultative p63+ progenitors that contribute to alveolar regeneration, indicating a potential therapeutic target for lung treatment after injuires.
Project description:During development of the human cerebral cortex, multipotent neural progenitors generate excitatory neurons and glial cells. This process is faithfully recapitulated in brain organoids. By using telencephalic brain organoids grown using a dual reporter cell line to isolate neural progenitors and neurons we generated a cell type and developmental stage-specific transcriptome dataset..
Project description:During development of the human cerebral cortex, multipotent neural progenitors generate excitatory neurons and glial cells. This process is faithfully recapitulated in brain organoids. By using telencephalic brain organoids grown using a dual reporter cell line to isolate neural progenitors and neurons we generated a cell type and developmental stage-specific ATAC-seq dataset.
Project description:We established a novel alveolar epithelial culture method, called "On-Gel" culture. To characterize the "On-Gel" culture, we compared each transcriptome of the cultured cells in "On-Gel", fibroblast dependent-alveolar organoids (FD-AO) and fibroblast-free alveolar organoids (FF-AO) and their progenitor cells (CPMhigh Lung Progenitors).
Project description:Underdeveloped lungs are a primary cause of morbidity and mortality in premature infants, but our ability to help these patients by speeding up lung development are hindered by a lack of understanding of human lung developmental biology. Here, we performed single cell RNA sequencing of the human fetal lung from samples spanning from 11.5 weeks gestation to 21 weeks gestation from the distal lung, middle airways, and the tracheal epithelium. The primary goal of this experiment was to define fetal cell states to serve as a gold standard for pluripotent stem cell-derived lung cells and tissues, and to identify potential signaling pathways that drive differentiation of lung progenitor cells to mature cell types. Additionally, we generated bud tip progenitor organoids from 12 week human fetal lung bud tip progenitors. We show that treatment of bud tip progenitor organoids with a short pulse of dual SMAD activation (BMP4+TGFb1) led to the upregulation of lung basal cell markers, a cell type that serves as a critical stem cell for the adult airway, and that further treatment with dual SMAD inhibition leads to the generation of airway-like organoids containing differentiated cell types of the adult airway, including basal stem cells.