Project description:We investigated whether in vitro expansion of human alveolar epithelial type II cells is possible. We found that human endogenous human alveolar epithelial type II cells can be cultured and passaged. The culture system enabled retroviral gene transduction into human alveolar epithelial type II cells. We performed RNA sequencing of human alveolar epithelial type II cells transduced with mutant surfactant protein C or control vector.
Project description:We induced differentiation from human induced pluripotent stem cell (hiPSC)-derived alveolar type2 (AT2) cells into hiPSC-derived 2D alveoalr type 1 (2D-iAT1) cells. Single cell RNA sequencing revealed that 2D-iAT1 cells were composed of three clusters.
Project description:Following lung injury, alveolar regeneration is characterized by the transformation of alveolar type 2 (AT2) cells, via a transitional KRT8+ state, into alveolar type 1 (AT1) cells. In lung disease, dysfunctional intermediate cells accumulate, AT1 cells are diminished and fibrosis occurs. Using single cell RNA sequencing datasets of human interstitial lung disease, we found that interleukin-11 (IL11) is specifically expressed in aberrant KRT8 expressing KRT5-/KRT17+ and basaloid cells. Stimulation of AT2 cells with IL11 or TGFβ1 caused EMT, induced KRT8+ and stalled AT1 differentiation, with TGFβ1 effects being IL11 dependent. In bleomycin injured mouse lung, IL11 was increased in AT2-derived KRT8+ cells and deletion of Il11ra1 in lineage labeled AT2 cells reduced KRT8+ expression, enhanced AT1 differentiation and promoted alveolar regeneration, which was replicated in therapeutic studies using anti-IL11. These data show that IL11 maintains AT2 cells in a dysfunctional transitional state, impairs AT1 differentiation and blocks alveolar regeneration across species.
Project description:The alveolar type 1 (AT1) cell covers >95% of the gas exchange surface and is extremely thin to facilitate passive gas diffusion. The development of this highly specialized cell is poorly understood including fundamental questions regarding cell number and morphology. Using new molecular stereology and single cell imaging methods, we show that AT1 cells develop via a non-proliferative two-step process while maintaining proliferative potential. In the flattening step, AT1 cells remodel cell junctions and undergo molecular specification. In the folding step, AT1 cells are sculptured to match secondary septa formation, resulting in a single AT1 cell spanning multiple alveoli. AT1 cells grow in size by >10-fold, fueling most of the postnatal lung growth. Strikingly AT1 cells proliferate upon ectopic SOX2 expression and undergo stage-dependent cell fate reprogramming. These results contradict the traditional view of AT1 cells being terminally differentiated and provide insights to alveolar maturation. In this experiment, we conducted next-generation sequencing on flow-sorter AT1 cells isolated from mouse lungs ectopically expressing Sox2 under the control of the AT1-specific promoter Scnn1a versus control AT1 cells. Two samples of Sox2-expressing AT1 cells versus two control AT1 samples.
Project description:Comparison of rat freshly-isolated alveolar epithelial type I cells, freshly-isolated type II cells, and type II cells cultured for 7 days Keywords = rat, alveolar epithelial type I cells, cultured type II cells Keywords: parallel sample
Project description:Sepsis is a serious systemic inflammatory reaction, which often leads to acute lung injury, and then affects lung function. This study aimed to explore the molecular mechanism of the interaction between il1b+ alveolar resident macrophages and pulmonary endothelial cells during sepsis induced lung injury using single-cell RNA sequencing technology.
