Project description:Pulmonary fibrosis results from dysregulated repair of damaged tissue caused by persistent injury of lung epithelium. Multiple cell types in the lung are involved in the process of repair. During lung fibrogenesis, normal endothelial cells (EC) are re-programmed into fibrosis-associated EC. Transcriptional factors that control re-programming are poorly understood. Using single cell RNA-sequencing of EC from donor and idiopathic pulmonary fibrosis (IPF) lungs, and lungs from bleomycin-treated mice, we identified endothelial transcription factors (TF) that were differentially expressed during fibrosis. Focusing on one of endothelial TF, FOXF1, we demonstrated that FOXF1 is decreased in EC within human IPF and mouse bleomycin-injured fibrotic lungs.
Project description:Sepsis patients are at increased risk for hospital-acquired pulmonary infections, potentially due to post-septic immunosuppression known as the compensatory anti-inflammatory response syndrome (CARS). CARS has been attributed to leukocyte dysfunction, with an unclear role for endothelial cells. The pulmonary circulation is lined by an endothelial glycocalyx, a heparan sulfate-rich layer essential to pulmonary homeostasis. Heparan sulfate degradation occurs early in sepsis, leading to lung injury. Endothelial synthesis of new heparan sulfates subsequently allows for glycocalyx reconstitution and endothelial recovery. We hypothesized that remodeling of the reconstituted endothelial glycocalyx, mediated by alterations in the endothelial machinery responsible for heparan sulfate synthesis, contributes to CARS. Our experimental animal model of CARS recapitulated post-septic immunosuppression, coincidentally with structural remodeling of endothelial glycocalyx heparan sulfate. We used microarray to identify which heparan sulfate modifying enzyme is responsible for the remodeling of post-septic reconstituted glycocalyx, characterized with enrichment of heparan sulfate disaccharides sulfated at the 6-O position of glucosamine.
Project description:Pulmonary fibrosis results from dysregulated repair of damaged tissue caused by persistent injury of lung epithelium. Multiple cell types in the lung are involved in the process of repair. During lung fibrogenesis, normal endothelial cells (EC) are re-programmed into fibrosis-associated EC. Transcriptional factors that control re-programming are poorly understood. Using single cell RNA-sequencing of EC from donor and idiopathic pulmonary fibrosis (IPF) lungs, and lungs from bleomycin-treated mice, we identified endothelial transcription factors (TF) that were differentially expressed during fibrosis. Focusing on one of endothelial TF, FOXF1, we demonstrated that FOXF1 is decreased in EC within human IPF and mouse bleomycin-injured fibrotic lungs.
Project description:Pulmonary fibrosis results from dysregulated repair of damaged tissue caused by persistent injury of lung epithelium. Multiple cell types in the lung are involved in the process of repair. During lung fibrogenesis, normal endothelial cells (EC) are re-programmed into fibrosis-associated EC. Transcriptional factors that control re-programming are poorly understood. Using single cell RNA-sequencing of EC from donor and idiopathic pulmonary fibrosis (IPF) lungs, and lungs from bleomycin-treated mice, we identified endothelial transcription factors (TF) that were differentially expressed during fibrosis. Focusing on one of endothelial TF, FOXF1, we demonstrated that FOXF1 is decreased in EC within human IPF and mouse bleomycin-injured fibrotic lungs.
Project description:Disruption of pulmonary vascular homeostasis is a central feature of viral pneumonia, wherein endothelial cell (EC) death and subsequent angiogenic responses represent critical determinants of the outcome of severe lung injury. A more granular understanding of the fundamental mechanisms driving reconstitution of the lung endothelium is necessary to facilitate therapeutic targeting of vascular repair. Here, we applied single-cell RNA sequencing (scRNA-seq) to profile lung ECs from mice on D0, D20 and D30 post influenza infection. Our data revealed the dynamics of endothelial subsets during influenza injury.
Project description:Endothelial cell (EC) dysfunction plays a key role in the pathogenesis of pulmonary arterial hypertension (PAH). To avoid cell cultures and whole lung tissue samples, we have, for the first time, used CD31 antibody coated magnetic beads in conjunction with genome scale RNA expression microarrays to profile ECs in vivo at any stage of PAH. We hypothesized that targeting early stages of the disease would identify novel mediators of PAH and genes linked to bone morphogenetic protein receptor 2 (BMPR2) signaling. Rats were treated with either monocrotaline (60mg/kg) or saline as control with 4 animals in each experimental group. Gene expression profiling was performed on primary pulmonary endothelial cells directly after isolation from whole lung tissue 5 days after treatment.
Project description:Pulmonary arterial hypertension (PAH) is a severe and incurable pulmonary vascular disease. One of the primary origins of PAH is pulmonary endothelial dysfunction leading to vasoconstriction, aberrant angiogenesis and smooth muscle cell proliferation, endothelial-to-mesenchymal transition, thrombosis and inflammation. Our objective was to study the epigenetic variations in pulmonary endothelial cells (PEC) through a specific pattern of DNA methylation.
Project description:Pulmonary arterial hypertension (PAH) is a severe and incurable pulmonary vascular disease. One of the primary origins of PAH is pulmonary endothelial dysfunction leading to vasoconstriction, aberrant angiogenesis and smooth muscle cell proliferation, endothelial-to-mesenchymal transition, thrombosis and inflammation. Our objective was to study the epigenetic variations in pulmonary endothelial cells (PEC) through a specific pattern of DNA methylation. DNA was extracted from cultured PEC from patients with idiopathic PAH (n=11), heritable PAH (n=10) and controls (n=18). ). DNA methylation was assessed using the Illumina HumanMethylation450 Assay. After normalization, samples and probes were clustered according to their methylation profile. Differential clusters were functionally analysed using bioinformatics tools.