ScRNA-seq in FFPE lung tissues of patients with IPF
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ABSTRACT: We performed scRNA-seq in FFPE lung tissues of patients with IPF to identify the cellular source of a transcriptomic signature in lungs of patients with IPF
Project description:BACKGROUND: Idiopathic Pulmonary Fibrosis (IPF) is a lethal lung disease of unknown etiology. A major limitation in transcriptomic profiling of lung tissue in IPF has been a dependence on snap-frozen fresh tissues (FF). In this project we sought to determine whether RNA-Seq could be used to identify IPF expression profiles from archived Formalin-Fixed Paraffin-Embedded (FFPE) lung fibrotic tissue. RESULTS: We isolated total RNA from 7 IPF and 5 control FFPE lung tissues (median archived time 6 years) and performed 50 bp paired-end sequencing on Illumina 2000 HiSeq. TopHat2 was used to map sequencing reads to the human genome. On average ~62 million reads (53.4% of ~116 million reads) were mapped per sample. Cufflinks calculated FPKM values (Fragments per Kilobase of exon per Million) and identified differentially expressed genes between the IPF and control samples. Here we show that RNA-Seq data obtained from FFPE lung tissues is comparable to microarray data obtained from IPF fresh frozen tissues. Pathway enrichment and network analysis confirmed numerous IPF relevant genes and pathways. CONCLUSION: Our results demonstrate that transcriptomic analysis of RNA obtained from archived FFPE lung tissues is feasible. Therefore FFPE IPF lungs can be used as a valid and reliable source for transcriptomic profiling in IPF
Project description:Tertiary lymphoid structures (TLS) are commonly observed in human idiopathic pulmonary fibrosis (IPF) lungs. The specific immune and non-immune cells in the TLS of IPF patients, and the factors that drive TLS formation, remain largely unknown. Here we spatially deconvoluted immune and non-immune cells in the TLS of human IPF lungs, and examined the signals underlying TSL development in IPF patients. We identified a novel subset of CCL19hi-IPF-associated-mural cells (CCL19hiIAMC) that enveloped the vessels inside the TLS. CCL19hiIAMCs were the major source of CCL19 inside the TLS of IPF lungs, attracting T/B lymphocytes and unique CCR7+DCs to drive TLS formation. CCL19hiIAMCs also provided other pro-TLS and proinflammatory molecules to promote lymphocyte maturation and tissue inflammation. Our data also reveal that various IPF-associated fibroblasts surrounded the TLS, promoting TLS development and plasma cells dissemination via CXCL12/CXCR4 signaling. CCR7 and CXCR4 signaling attracted lymphocytes and DCs that upregulated pro-TLS genes in the IPF microenvironment to enhance TLS formation. Together, these findings have deconvoluted the cell subsets and their transcriptomes in the TLS of IPF lungs and suggest that novel CCL19hiIAMCs may drive TLS formation in collaboration with various immune cells and fibroblasts.
Project description:Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease characterized by repetitive alveolar injuries with excessive deposition of extracellular matrix (ECM) proteins. A crucial need in understanding IPF pathogenesis is identifying cell types associated with histopathological regions, particularly local fibrosis centers known as fibroblast foci. To address this, we integrated published spatial transcriptomics and single-cell RNA sequencing (scRNA-seq) transcriptomics and adopted the Query method and the Overlap method to determine cell type enrichments in histopathological regions. Distinct fibroblast cell types are highly associated with fibroblast foci, and transitional alveolar type 2 and aberrant KRT5-/KRT17+ epithelial cells are associated with morphologically normal alveoli in human IPF lungs. Furthermore, we employed laser capture microdissection directed mass spectrometry to profile proteins. By comparing with another published similar dataset, common differentially expressed proteins and enriched pathways related to ECM structure organization and collagen processing were identified in fibroblast foci. Importantly, cell type enrichment results from innovative spatial proteomics and scRNA-seq data integration accord with those from spatial transcriptomics and scRNA-seq data integration, supporting the capability and versatility of the entire approach. In summary, we integrated spatial multi-omics with scRNA-seq data to identify disease-associated cell types and potential targets for novel therapies in IPF intervention. The approach can be further applied to other disease areas characterized by spatial heterogeneity.
Project description:The activated fibroblast is the central effector cell for the progressive fibrotic process that characterizes idiopathic pulmonary fibrosis (IPF). An understanding of the genomic phenotype of this cell in isolation is essential to the understanding of disease pathogenesis and is integral to strategizing therapeutic trials. Employing a unique technique that minimizes cellular phenotypic alterations, we characterized the genomic phenotype of non-cultured pulmonary fibroblasts from the lungs of patients with advanced IPF. This approach revealed several novel genes and pathways previously unreported in IPF fibroblasts. Specifically, we demonstrate altered expression in proteasomal constituents, ubiquitination mediators, the Wnt pathway and several cell cycle regulators suggestive of loss of normal cell cycle controls. The pro-inflammatory cytokine CXCL12 was also up-regulated which may provide a mechanism for fibrocytes’ recruitment, while up-regulated oncogenic KIT may promote fibroblast over proliferation. Paradoxically, pro-apoptotic inducers such as death inducing ligand TRAIL (TNFSF10) and pro-apoptotic Bax were also up-regulated. This comprehensive description of altered gene expression within IPF fibroblasts sheds further light on the complex interactions that characterize IPF. Further studies including therapeutic interventions directed at these pathways hold promise for the treatment of this devastating disease. 58 samples of total RNA isolated from 12 lungs of patients with end-stage idiopathic pulmonary fibrosis and 6 donors of normal lungs (controls) who were designated brain dead, non-diseased donors whose lungs failed criteria for transplantation and who were organ donors for research. RNA extraction followed the Qiagen RNeasy Kit using QIshredder columns for shredding of DNA contiminants. Experimental/control samples were amplified amino-allylated RNA labeled with Cy5 and Stratagene Reference RNA was amplified and amino-allylated and labeled with Cy3. Amplification was one round using Ambion MessageAmp II kit with amino-allylated UTP according to the protocol of the Duke University Institute for Genome Sciences and Policy. Amplification and amino-allylation of the Stratagene Reference RNA and Hybridization of Reference with patient samples and controls was done by the Duke Institute for Genomic Sciences and Policy.
Project description:Idiopathic pulmonary fibrosis (IPF) is a progressive lethal interstitial lung disease of unkown etiology with limited effective therapies. The pathogenic mechanisms of IPF remain unkown. Emerging evidences indicate that abnormal behaviors of fibroblasts in IPF are associated with a variety of genetic alterations and aberrant reactivation of developmental signaling pathways. We compared gene expression profiles in fibrotic lung tissues from IPF patients and normal lung tissues from patients with primary spontaneous pneumothorax using cDNA microarray to examine the mechnisms involved in the pathogenesis of IPF.
Project description:To understand the cellular composition and transcriptional phenotype of fibrotic lung tissue we performed single-cell RNA-seq on stromal, immune, epithelial, and endothelial cell populations from human lung explants. Tissue was collected from normal control lungs, patients with idiopathic pulmonary fibrosis (IPF), and patients with systemic sclerosis associated interstitial lung disease (SSc-ILD). Using the 10X Genomics Chromium platform, we generated transcriptional profiles of approximately 200,500 cells across 4 IPF, 3 SSc-ILD and 3 normal control lungs.
Project description:To further understand the pathologic microenvironment in IPF, we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to distinguish normal and IPF lung in normal-looking, fibrotic foci and hyperplastic areas of IPF lung. Four IPF lungs were dissected into normal-looking, fibrotic foci and hyperplastic areas by Laser-Capture-Microdissection. Gene expression analysis showed that 638 significantly different genes were identified that clearly distinguished the different IPF microenvironments . Among them, MMP19 was revealed as one of the most significantly up-regulated genes that distinguished normal looking epithelial cells (N) to hyperplastic epithelial cells, MMP19 up-regulation in IPF lungs was verified by immunohistochemical (IHC), qRT-PCR and Western-blot. IPF lungs are heterogeneity complex, which comprise normal looking area, fibrotic foci and hyperplastic area. In this study we separated the normal, fibrotic foci and hyperplastic area by LCM and employed Agilent whole genome gene expression microarray profiling to identify genes with the potential to distinguish the unique microenironment of IPF
Project description:Viruses in acute exacerbations of idiopathic pulmonary fibrosis Keywords: viral detection BAL from patients with acute exacerbations of IPF and stable IPF were hybridized to a pan-viral cDNA microarray to evaluate the presence of virus during these episodes
Project description:Accelerated senescence in lung epithelial cells is known to play a key role in the pathogenesis of idiopathic pulmonary fibrosis (IPF). However, the exact mechanisms underlying the IPF-related epithelial cell phenotype have yet to be elucidated. Increasing evidence supports the concept that extracellular vesicles (EVs), including exosomes and microvesicles, mediate intercellular communication that contributes to diverse aspects of physiology and pathogenesis. Here, we demonstrate that lung fibroblasts (LFs) from IPF patients accelerate epithelial cell senescence via EV-mediated transfer of LF-derived pathogenic cargo to lung epithelial cells. Mechanistically, IPF LF-derived EVs increase mitochondrial reactive oxygen species (mtROS) and associated mitochondrial damage in lung epithelial cells, leading to mtROS-mediated activation of the DNA damage response and subsequent epithelial cell senescence. We show that IPF LF-derived EVs contain elevated levels of miR-23b-3p and miR-494-3p that are responsible for suppressing SIRT3, resulting in the EV-induced phenotypic changes of lung epithelial cells. Furthermore, we observe that miR-23b-3p and miR-494-3p expression increases in lung epithelial cells from IPF patients’ lungs. Finally, the levels of miR-23b-3p and 494-3p found in IPF LF-derived EVs correlate positively with IPF disease severity. These findings reveal that the accelerated epithelial cell mitochondrial damage and senescence observed during IPF pathogenesis are caused by a novel mechanism in which SIRT3 is suppressed by miR-containing EVs derived from IPF fibroblasts.