Project description:Lung fibroblasts include several subpopulations. We used single cell RNA sequencing (scRNAseq) to analyze the heterogeneity of lung fibroblasts.
Project description:Analysis of transcriptional profile of lung resident macrophages during acute and resolution phase of LPS inhalation induced lung injury. Because macrophages coordinate both the induction and resolution of inflammatory lung injury, we examined the transcriptional signatures of resident lung macrophages isolated from LysM-GFP mice during baseline (0h), peak of injury (4h), and during the resolution phase (24h).
Project description:We studied the role of p16INK4a+ fibroblasts in lung fibrosis. We used single cell RNA seq (scRNA-seq) to characterize p16INK4a+ fibroblasts in fibrotic lung.
Project description:A specialized population of memory CD8+ T-cells resides in the epithelium of the respiratory tract to maintain protection against recurring infections. These cells express CD69 and the integrin αβ7 (CD103) and correspond to tissue resident memory T-cells (TRM) also described in intestine, liver and brain. A less well characterized population of CD103- CD8+ T-cells also resides in lungs and expresses markers characteristic of effector memory T-cells (TEM). We determined the transcriptional profiles of these memory CD8+ T-cell subsets retrieved from human lung resection samples and compared these with corresponding T-cell populations from peripheral blood of the same individuals. Our results demonstrate that each of the populations exhibits a distinct transcriptional identity. We found that the lung environment has a major impact on gene expression profiles. Thus, transcriptomes from CD103+ and CD103- subsets from lungs are much more resemblant to one another than to those from CD103+ or CD103- memory CD8+ T-cells from blood. TRM express specific sets of chemokine receptors, in accordance with their unique migratory properties. Furthermore, these cells constitutively express cytokine and cytotoxic genes for immediate effector function and chemokines to attract auxiliary immune cells. At the same time, multiple genes encoding inhibitory regulators are also expressed. This suggests that rapid ability to unleash effector functions is counterbalanced by programmed restraint, a combination that may be critical in the exposed but delicate tissue of the lung. Comprehensive sets of transcription factors were identified that characterize the memory CD8+ populations in the lungs. Prominent among these were components of the Notch pathway. Using mice genetically lacking expression of the NOTCH1 and NOTCH2 receptors in T-cells, we demonstrated that Notch controls both the number of lung TRM as well as the function of lung TEM. Our data illustrate the adaptation of lung resident T-cells to the requirements of the respiratory epithelial environment. Defining the molecular imprinting of these cells is important for rational vaccine design and may help to improve the properties of T-cells for adoptive cellular therapy. Material was collected from a total of 6 subjects. Three patients underwent a lobectomy for a peripheral primary lung tumor and three received lung transplantation because of end-stage pulmonary disease (COPD). Lung mononuclear cells where isolated after digestion of the partial or complete human lung resection material. Paired peripheral blood mononuclear cells were also isolated. CD8+CD16-CD56- T-cells were sorted for expression of CD103 (ITGAE). Lung and blood derived CD103+ and CD103- T-cell fractions were directly lysed after FACS sorting or stimulated overnight with antiCD3/28 beads. Due to the low frequency of resting (non-stimulated) CD103+ T-cells in peripheral blood this subset was obtained from five non-related buffy coat donors. RNA was isolated from 36 sorted cell samples and hybridized on Illumina HumanHT-12 V4.0 microarrays. Eight microarray samples (including two samples from the buffy coat donors) were excluded after hybridization since their average signal was too low.
Project description:Idiopathic pulmonary fibrosis (IPF) is a devastating disease with only three to five years of the median survival. Fibroblast proliferation is a hallmark of IPF as well as secretion of extracellular matrix proteins from fibroblasts. However, it is still uncertain how IPF fibroblasts acquire the ability to progressively proliferate. Periostin is a matricellular protein that is highly expressed in the lung tissues of IPF patients and plays a critical role in the pathogenesis of pulmonary fibrosis. However, it remains undetermined whether periostin affects proliferation of lung fibroblasts. In this study, we first comprehensively tried to identify periostin-dependently expressed genes in lung fibroblasts finding that many cell-cycle–related genes are involved in the gene profile. We confirmed that periostin silencing downregulates expression of several cell-cycle–related molecules including the cyclin family, the CDK family, the E2F family, and the transcriptional factors such as B-MYB and FOXM1 in lung fibroblasts. Accordingly, periostin silencing slowed proliferation of lung fibroblasts and affects the distribution of cell cycle particularly at the G1/S checkpoint and drives the cells into G1 arrest. Lung fibroblasts derived from IPF patients also required periostin for maximum proliferation. Moreover, CP4715, a potent inhibitor against integrin V3, a periostin receptor, downregulated proliferation along with expression of cell-cycle–related genes in IPF lung fibroblasts as well as normal lung fibroblasts. These results demonstrate that periostin plays a critical role in proliferation of lung fibroblasts and provide us a beneficial basis to apply the inhibitors against the periostin/integrin V3 interaction to IPF patients.