Project description:This SuperSeries is composed of the following subset Series: GSE23303: Gene expression profiling of human atherosclerotic plaque: Laser capture microscopy of smooth muscle cells and macrophages GSE23304: Gene expression profiling of human atherosclerotic plaque: 101 peripheral plaques GSE24495: Gene expression profiling of human atherosclerotic plaque: Carotid plaque GSE24702: Gene expression profiling of human atherosclerotic plaque: 290 peripheral plaques Refer to individual Series
Project description:In order to identify potential new biomarkers of atherosclerotic plaque composition we performed a large scale analysis of gene expression patterns in human atherosclerotic lesions. Whole genome expression analysis of 101 peripheral plaques identified a robust gene signature (1514 genes) dominated by inflammatory processes, and cholesterol metabolism and storage genes. Specific pathways enriched in this signature included activation of the Toll-like receptor signaling pathway, T-cell activation, cholesterol efflux, oxidative stress response, inflammatory cytokine production, vasoconstriction and lysosomal activity. Analysis of gene expression in plaque micro-dissected material revealed that the signature is strongly up-regulated in macrophage-rich regions and down-regulated in regions with high smooth muscle cell content. A smaller qPCR biomarker panel and inflammatory composite score (ICS) were developed to facilitate clinical translation of discoveries from gene expression profiling. We found that ICS correlates with histological features related to plaque vulnerability. In addition, ICS is able to separate groups of plaques obtained from symptomatic and asymptomatic patients undergoing carotid endarerectomy. In summary, we identified a robust mRNA biomarker panel associated with histo-pathological as well as clinical hallmarks of vulnerable atherosclerotic plaque. This panel may be used as a diagnostic and prognostic tool in clinical setting to evaluate novel anti-atherosclerotic therapies. 6 human carotid plaques were sectioned in 1 mm thick slices. Alternative slices were used for gene expression profiling in Affymetrix/Merck custom 1.0 arrays (GPL10687), or for immunohistochemistry studies (CD68, Actin)
Project description:In order to identify potential new biomarkers of atherosclerotic plaque composition we performed a large scale analysis of gene expression patterns in human atherosclerotic lesions. Whole genome expression analysis of 101 peripheral plaques identified a robust gene signature (1514 genes) dominated by inflammatory processes, and cholesterol metabolism and storage genes. Specific pathways enriched in this signature included activation of the Toll-like receptor signaling pathway, T-cell activation, cholesterol efflux, oxidative stress response, inflammatory cytokine production, vasoconstriction and lysosomal activity. Analysis of gene expression in plaque micro-dissected material revealed that the signature is strongly up-regulated in macrophage-rich regions and down-regulated in regions with high smooth muscle cell content. A smaller qPCR biomarker panel and inflammatory composite score (ICS) were developed to facilitate clinical translation of discoveries from gene expression profiling. We found that ICS correlates with histological features related to plaque vulnerability. In addition, ICS is able to separate groups of plaques obtained from symptomatic and asymptomatic patients undergoing carotid endarerectomy. In summary, we identified a robust mRNA biomarker panel associated with histo-pathological as well as clinical hallmarks of vulnerable atherosclerotic plaque. This panel may be used as a diagnostic and prognostic tool in clinical setting to evaluate novel anti-atherosclerotic therapies.
Project description:Plaque rupture and subsequent thrombus formation is responsible for the majority of clinical complications of atherosclerosis and nonetheless our understanding of what underlies plaque vulnerability and rupture is still sparse and mostly deductively based on animal models and in vitro studies. We adopted five different -omics platforms to compare ruptured atherosclerotic and advanced-stable tissue within the same carotid plaque specimen from 24 carotid endarterectomy patients. Segments designated as stable feature either a fibrous cap atheroma or pathological intimal thickening. Segments designated as ruptured include a thrombus and/or presented intraplaque hemorrhage. For the present study only those samples were selected for further analysis that were flanked by two segments of identical classification, be it stable (S) or ruptured (R); and were derived from CEA specimen that contained plaque segments of both classifications.
Project description:Background: Carotid atherosclerosis is a multifaceted disease orchestrated by a myriad of cell-cell communication that drives progression along a clinical continuum (asymptomatic to symptomatic). Extracellular vesicles (EVs) are lipid bilayer membrane-enclosed cell-derived nanoparticles that represent a new paradigm in cellular communication. Little is known about their biological cargo, cellular origin/destination, and functional roles in human atherosclerotic plaque. Methods: EVs were enriched via size exclusion chromatography from human carotid endarterectomy samples dissected into plaque and marginal zones (n= 29 patients, paired plaque and marginal zone; symptomatic n=16, asymptomatic n=13), with further density gradient ultracentrifugation for proteomic analysis. EV cargoes were assessed via whole transcriptome miRNA sequencing and mass spectrometry-based proteomics. EV multi-omics were integrated with publicly available bulk and single cell RNA-sequencing (scRNA-seq) datasets to predict EV cellular origin and ligand-receptor interactions and multi-modal biological network integration of EV-cargo was completed. EV functional impact was assessed with endothelial angiogenesis assays. Results: Human carotid plaques contained greater quantities of EVs than adjacent marginal zones. EV-miRNA and protein content was different in diseased plaque versus adjacent marginal zones, with differential functions in key atherogenic pathways. EV cellular origin analysis suggested that tissue EV signatures originated from endothelial cells (EC), smooth muscle cells (SMC), and immune cells. Furthermore, EV signatures from SMCs and immune cells were most enriched in the marginal and plaque zones, respectively. Integrated tissue vesiculomics and scRNA-seq indicated complex EV-vascular cell communication strategies that changed with disease progression and plaque vulnerability (symptomatic disease). Plaques from symptomatic patients, but not asymptomatic patients, were characterized by increased involvement of endothelial pathways and more complex ligand-receptor interactions, relative to their marginal zones. Plaque-EVs were predicted to mediate communication with ECs and together with pathway enrichment analysis delineated a strong endothelial signature with potential roles in angiogenesis and neovascularization – well-known indices of plaque instability. This was corroborated functionally, wherein human carotid symptomatic plaque EVs induced sprouting angiogenesis (number and length of sprouts) in comparison to their matched marginal zones. Conclusion: Our findings indicate that EVs may drive dynamic changes in plaques through EV-vascular cell communication and effector functions that typify vulnerability to rupture, precipitating symptomatic disease. The discovery of endothelial-directed processes mediated by EVs creates new avenues for novel therapeutics in atherosclerosis.
Project description:The aim of this study was to understand if gene expression in atherosclerotic plaque macrophages is altered by diabetes. Laser capture microdissection (LCM) was used to specifically isolate macrophage enriched regions from human carotid atherosclerotic plaque samples. RNA isolated was then sent for sequencing using the Illumina bead array system. Gene expression data revealed that 106 genes from diabetic macrophages are differentially expressed (FDR<0.2) and provide mechanistic evidence for the involvement of Runt-related transcription factor 1 (RUNX1) in the development of diabetic atherosclerosis.
Project description:In order to identify potential new biomarkers of atherosclerotic plaque composition we performed a large scale analysis of gene expression patterns in human atherosclerotic lesions. Whole genome expression analysis of 101 peripheral plaques identified a robust gene signature (1514 genes) dominated by inflammatory processes, and cholesterol metabolism and storage genes. Specific pathways enriched in this signature included activation of the Toll-like receptor signaling pathway, T-cell activation, cholesterol efflux, oxidative stress response, inflammatory cytokine production, vasoconstriction and lysosomal activity. Analysis of gene expression in plaque micro-dissected material revealed that the signature is strongly up-regulated in macrophage-rich regions and down-regulated in regions with high smooth muscle cell content. A smaller qPCR biomarker panel and inflammatory composite score (ICS) were developed to facilitate clinical translation of discoveries from gene expression profiling. We found that ICS correlates with histological features related to plaque vulnerability. In addition, ICS is able to separate groups of plaques obtained from symptomatic and asymptomatic patients undergoing carotid endarerectomy. In summary, we identified a robust mRNA biomarker panel associated with histo-pathological as well as clinical hallmarks of vulnerable atherosclerotic plaque. This panel may be used as a diagnostic and prognostic tool in clinical setting to evaluate novel anti-atherosclerotic therapies. Total RNA from peripheral plaque (n=101) profiled in the Merck/Agilent 44k v1.1 against a reference pool of total RNA from 7 carotid plaques.