Project description:Idiopathic pulmonary fibrosis (IPF) is a devastating fibrotic lung disease of unknown etiology and limited therapeutic options. In this report, we characterize what we believe is a novel CCR10+ epithelial cell population in IPF lungs. There was a significant increase in the percentage of CCR10+ epithelial cells in IPF relative to normal lung explants and their numbers significantly correlated to lung remodeling in humanized NSG mice. Cultured CCR10-enriched IPF epithelial cells promoted IPF lung fibroblast invasion and collagen 1 secretion. Single-cell RNA sequencing analysis showed distinct CCR10+ epithelial cell populations enriched for inflammatory and profibrotic transcripts. Consistently, cultured IPF but not normal epithelial cells induced lung remodeling in humanized NSG mice, where the number of CCR10+ IPF, but not normal, epithelial cells correlated with hydroxyproline concentration in the remodeled NSG lungs. A subset of IPF CCR10hi epithelial cells coexpress EphA3 and ephrin A signaling induces the expression of CCR10 by these cells. Finally, EphA3+CCR10hi epithelial cells induce more consistent lung remodeling in NSG mice relative to EphA3-CCR10lo epithelial cells. Our results suggest that targeting epithelial cells, highly expressing CCR10, may be beneficial in IPF.
Project description:Idiopathic pulmonary fibrosis (IPF) is a prevalent, progressive, and incurable fibroproliferative lung disease. The phenotype of IPF fibroblasts is characterized by their ability to elude the proliferation-suppressive properties of polymerized type I collagen. The mechanism underlying this pathological response is incompletely understood but involves aberrant activation of the phosphatidylinositol 3-kinase-Akt signaling pathway owing to inappropriately low phosphatase and tensin homolog phosphatase activity. Akt can phosphorylate and inactivate the forkhead box O3a (FoxO3a) transcriptional factor, which, when transcriptionally active, increases the expression of the CDK inhibitor p27 and promotes cell cycle arrest. Herein, we demonstrate that IPF fibroblasts display high levels of inactive FoxO3a compared with nonfibrotic control fibroblasts because of their high Akt activity. We found that p27 levels are decreased in IPF compared with control fibroblasts cultured on polymerized collagen. Furthermore, overexpression of FoxO3a in IPF fibroblasts increases p27 levels and suppresses the ability of IPF fibroblasts to proliferate on polymerized collagen. In contrast, the expression of dominant-negative FoxO3a augmented control fibroblast proliferation. IHC examination of fibroblastic foci in IPF lung tissue demonstrates the presence of inactive FoxO3a in cells within fibroblastic foci. These data indicate that the ability of IPF fibroblasts to circumvent the proliferation-suppressive properties of polymerized collagen involves inactivation of FoxO3a by high Akt activity, resulting in down-regulation of p27.
Project description:RNA sequencing has been performed to investigate the transcriptomic profile of fibroblasts derived from apical and basal regions of idiopathic pulmonary fibrosis (IPF) and control (CTR) lungs. Lung fibroblasts were cultured onto T25 flasks until full confluence was reached. Fibroblasts were then harvested by trypsinization using 0.05% trypsin-EDTA and washed in Phosphate Buffered Saline (PBS). RNA was extracted using the RNeasy Mini kit protocol. Samples were then sent to the Australian Genome Research Facility (AGRF) where 1μg of RNA was submitted for next-generation sequencing. Once raw data returned, bioinformatics analysis was conducted. Results revealed little difference at the transcriptomic level between apical lung fibroblasts isolated from IPF and CTR donors. In contrast, there was a significant difference in gene expression between IPF and CTR lung basal fibroblasts with 90 differentially expressed genes (DEGs) identified in IPF basal fibroblasts. Gene ontology analysis of these 90 DEGs suggested that the most important functions were associated with receptor ligand activity, cell adhesion molecule binding, and integrin binding. Furthermore, fibroblasts isolated from the basal and apical sites of control lung were not significantly different. Interestingly, the lung basal fibroblasts from IPF patients were significantly different in their transcriptomic profile to that of apical fibroblasts from the same patients. 303 DEGs were identified in IPF basal fibroblasts compared with IPF apical fibroblasts. According to the GO analysis on these 303 DEGs, the most important function of the identified dysregulated genes was associated with the composition and function of the extracellular (ECM). Further pathway analysis identified 4 signaling pathways, namely arrhythmogenic right ventricular cardiomyopathy, calcium signaling pathway, dilated cardiomyopathy, and hematopoietic cell lineage. An interesting finding was that these IPF basal fibroblasts were clustered into two groups (Group 1 and Group 2). Analysis on these two groups found 3594 DEGs in Group 1 compared to Group 2. Go analysis suggested most of the identified dysregulated genes was involved in the composition and function of the ECM. Pathway analysis identified 28 dysregulated signaling pathways, including PI3K-Akt signaling pathway, TGF-β signaling pathway and Wnt signaling pathway. The results of the transcriptome analysis intimate that the IPF is more predominant in the basal lungs and the fibroblast-derived from the basal region of the fibrotic lungs may serve as a central role in IPF. Moreover, the dramatic difference between two groups of IPF basal fibroblasts might be linked to the differential response to the same drug occurred in IPF patients.
Project description:Rationale: Declining lung function in patients with interstitial lung disease is accompanied by epithelial remodeling and progressive scarring of the gas-exchange region. There is a need to better understand the contribution of basal cell hyperplasia and associated mucosecretory dysfunction to the development of idiopathic pulmonary fibrosis (IPF).Objectives: We sought to decipher the transcriptome of freshly isolated epithelial cells from normal and IPF lungs to discern disease-dependent changes within basal stem cells.Methods: Single-cell RNA sequencing was used to map epithelial cell types of the normal and IPF human airways. Organoid and air-liquid interface cultures were used to investigate functional properties of basal cell subtypes.Measurements and Main Results: We found that basal cells included multipotent and secretory primed subsets in control adult lung tissue. Secretory primed basal cells include an overlapping molecular signature with basal cells obtained from the distal lung tissue of IPF lungs. We confirmed that NOTCH2 maintains undifferentiated basal cells and restricts basal-to-ciliated differentiation, and we present evidence that NOTCH3 functions to restrain secretory differentiation.Conclusions: Basal cells are dynamically regulated in disease and are specifically biased toward the expansion of the secretory primed basal cell subset in IPF. Modulation of basal cell plasticity may represent a relevant target for therapeutic intervention in IPF.
Project description:Specific common and rare single nucleotide variants (SNVs) increase the likelihood of developing sporadic idiopathic pulmonary fibrosis (IPF). We performed target-enriched sequencing on three loci previously identified by a genome-wide association study to gain a deeper understanding of the full spectrum of IPF genetic risk and performed a two-stage case-control association study. A total of 1.7 Mb of DNA from 181 IPF patients was deep sequenced (>100×) across 11p15.5, 14q21.3 and 17q21.31 loci. Comparisons were performed against 501 unrelated controls and replication studies were assessed in 3968 subjects. 36 SNVs were associated with IPF susceptibility in the discovery stage (p<5.0×10-8). After meta-analysis, the strongest association corresponded to rs35705950 (p=9.27×10-57) located upstream from the mucin 5B gene (MUC5B). Additionally, a novel association was found for two co-inherited low-frequency SNVs (<5%) in MUC5AC, predicting a missense amino acid change in mucin 5AC (lowest p=2.27×10-22). Conditional and haplotype analyses in 11p15.5 supported the existence of an additional contribution of MUC5AC variants to IPF risk. This study reinforces the significant IPF associations of these loci and implicates MUC5AC as another key player in IPF susceptibility.
Project description:Idiopathic pulmonary fibrosis (IPF) is a disease related to AT2 cell. We used flow cytometry to analyze the epithelial component of donor and IPF lungs. From the live cells, we first excluded the CD31PosCD45Pos and then selected the EPCAMPos cells for further analysis using the human AT2 cell marker HTll-280 and the surface marker PD-L1. Our data indicate that, the bona fide differentiated AT2 cells (HTll-280High PD-L1Neg), were drastically reduced in the context of IPF. More interestingly, the number of HTll-280Low/Neg PD-L1High was drastically increased, suggesting that HTll-280Low PD-L1High epithelial cells could represent a pool of progenitors linked to the deficient AT2 lineage. The aim of this experiment is further characterization of AT2 and PDL1+ cells in donor and IPF.
Project description:Idiopathic pulmonary fibrosis (IPF) is a devastating disease for patients and their loved ones. Since initial efforts to characterize this disease in the 1960s, understanding of IPF has evolved considerably. Such evolution has continually challenged prior diagnostic and treatment paradigms, ushering in an era of higher confidence diagnoses with less invasive procedures and more effective treatments. This review details how research and clinical experience over the past half century have led to a rethinking of IPF. Here, the evolution in understanding of IPF pathogenesis, diagnostic evaluation and treatment approach is discussed.
Project description:The aim of the current study is to find plasma-based biomarker candidates for Idiopathic Pulmonary Fibrosis (IPF). Incidence of IPF seems to be increasing in Europe and there is significant mortality associated with IPF. There are no sensistive biomarkers for IPF and diagnosis is entirely clinical and/or histopathological which is often delayed. Minimally invasive biomarkers of IPF would be expected to aid clinicians perfrom early diagnosis of IPF enabling better management of the disease.