Project description:Fibrosis refers to the abnormal proliferation and excessive accumulation of fibrous tissue in an organ or tissue, typically caused by chronic injury or inflammation. Fibroblasts play a crucial role in the initiation and progression of fibrosis, with their excessive activation and overproduction of ECM being key mechanisms in fibrotic diseases. In this study, we constructed decellularized lung scaffolds from normal mice and bleomycin-induced lung decellularized scaffolds to analyze and compare the differential gene expression in control human fibroblasts, TGFβ-induced human fibroblasts, fibroblasts co-cultured with normal lung decellularized scaffolds, and fibroblasts co-cultured with bleomycin-induced lung decellularized scaffolds. This investigation aims to explore the impact of ECM on fibroblast activation and its underlying mechanisms.
Project description:Idiopathic pulmonary fibrosis (IPF) is the prototypic progressive fibrotic lung disease with a median survival of 2-4 years. Injury to and/or dysfunction of alveolar epithelium are strongly implicated in IPF disease initiation, but what factors determine why fibrosis progresses rather than normal tissue repair occurs remain poorly understood. We previously demonstrated that ZEB1-mediated epithelial-mesenchymal transition (EMT) in human alveolar epithelial type II (ATII) cells augments TGF-β-induced profibrogenic responses in underlying lung fibroblasts by paracrine signalling. Here we investigated bi-directional epithelial-mesenchymal crosstalk and its potential to drive fibrosis progression. RNA sequencing (RNA-seq) of lung fibroblasts exposed to conditioned media from ATII cells undergoing RAS-induced EMT identified many differentially expressed genes including those involved in cell migration and extracellular matrix (ECM) regulation. We confirmed that paracrine signalling between AS-activated ATII cells and fibroblasts augmented fibroblast recruitment and demonstrated that this involved a ZEB1-tissue plasminogen activator (tPA) axis. In a reciprocal fashion, paracrine signalling from TGF-β-activated lung fibroblasts or IPF fibroblasts induced RAS activation in ATII cells, at least partially via the secreted protein, SPARC. Together these data identify that aberrant bi-directional epithelial-mesenchymal crosstalk in IPF drives a chronic feedback loop that maintains a wound-healing phenotype and provides self-sustaining pro-fibrotic signals.
Project description:Azithromycin has been shown to have anti-fibrotic effects on idiopathic lung fibroblasts (IPF). We thus wanted to investigate involved genes and pathways by microarray analysis. We treated normal human lung fibroblasts with Azithromycin (50uM) for 24h and compared them to non-treated samples.
Project description:Pulmonary fibrosis is a chronic, progressive, and lethal interstitial lung disease. It is characterized by extracellular matrix deposition, fibroblast proliferation, and accumulation. Fibroblasts from normal or UIP histology were cultured and analyzed. Keywords: Fibroblasts from normal histology lung tissue or UIP histology lung tissue
