Project description:Human monocytes are phagocytic leucocytes which circulate in the peripheral blood and play important roles in immunity and inflammation. They also represent circulating metabolic sentinels in plasma, uptake lipids following food intake, and contribute to atherosclerotic plaque formation. We therefore investigated their homeostatic responses to food intake in vivo and to determine the response of human monocytes to food intake. We isolated monocyte subsets from the blood of healthy volunteers one hour before and four hours after a western type lunch.
Project description:Phenotypic and functional diversity between macrophage subpopulations reflects their plasticity to respond to microenvironmental signals. Apart from detecting differences in expression profiles, the comparison of the transcriptomes of different macrophage populations may also allow the definition of molecular similarities between these subsets. Transcriptome analysis of human Kuppfer cells, alveolar, splenic and atherosclerotic plaque residing macrophages using microarrays, identified 42 genes that are specifically expressed in atherosclerotic plaque macrophages. We also focus on the similarities in the transcriptome of human Kupffer cells, alveolar, splenic and atherosclerotic plaque residing macrophages. We hypothesized that these macrophages share a common expression signature. We performed microarray analysis on mRNA from these macrophage subsets (n = 4 patients) and developed a novel statistical method to identify genes with significantly similar expression levels. This method calculates the maximum difference in expression level of a gene, based on the estimated confidence interval on that genes expression variance. We listed the genes by equivalence ranking relative to their expression level. False Discovery Rate (FDR) estimation was used to determine significance. We identified 500 genes that had significantly equivalent expression levels in the macrophage subsets at an 5.5% FDR using a 90% confidence interval. Equivalently expressed genes, identified by this newly developed method, may not only help to dissect common molecular mechanisms, but also to identify cell or condition specific sets of marker genes that can be used for drug targeting and molecular imaging. Overall design: Macrophages were isolated from N=4 tissues, being atherosclerotic plaques from carotid artery (CA), and from three none-atherosclerotic tissues, being lung (LU), spleen (SP), and liver (LI). This was done within four individual patients, defined as 275, 282, 288 and 289. Each of the N=16 biological samples was hybridized in duplicate against a common reference RNA, resulting in a total of N=16 microarray hybridizations.
Project description:Small non-coding microRNAs (miRs) have emerged to play critical roles in cardiovascular biology. Monocytes critically drive atherosclerotic plaque formation, and can be subdivided into a classical and non-classical subset. Here we scrutinized the miR signature of human classical and non-classical monocytes, and compared miR expression profiles of atherosclerotic plaques from human carotid arteries and healthy arteries. Overall design: This study includes cell samples from human sorted classical and non-classical monocyte subset, as well as pooled sample from carotid artery plaque and Ae. mammaria.
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:Transcriptional profiling of stable and unstable atherosclerotic plaque segments from human carotid endatrerectomies Objective Comparison of gene expression in stable versus unstable atherosclerotic plaque may be confounded by interpatient variability. The aim of this study was to identify differences in gene expression between stable and unstable segments of plaque obtained from the same patient. Human carotid endarterectomy specimens were segmented and macroscopically classified using a morphological classification system. Two analytical methods, an intraplaque and an interplaque analysis, revealed 170 and 1916 differentially expressed genes, respectively using Affymetrix gene chip analysis. A total of 115 genes were identified from both analyses. The differential expression of 27 genes was also confirmed using quantitative-polymerase chain reaction on a larger panel of samples. Eighteen of these genes have not been associated previously with plaque instability, including the metalloproteinase, ADAMDEC1 (37-fold), retinoic acid receptor responder-1 (5-fold), and cysteine protease legumain (3-fold). Matrix metalloproteinase-9 (MMP-9), cathepsin B, and a novel gene, legumain, a potential activator of MMPs and cathepsins, were also confirmed at the protein level. The differential expression of 18 genes not previously associated with plaque rupture has been confirmed in stable and unstable regions of the same atherosclerotic plaque. These genes may represent novel targets for the treatment of unstable plaque or useful diagnostic markers of plaque instability. Differential gene expression in stable and unstable plaque was assessed by whole transcriptome analysis. Intraplaque analysis by QT-PCR confirmed the differential expression of 18 genes not associated previously with plaque rupture. These genes may represent novel targets for the treatment of unstable plaque or useful diagnostic markers of plaque instability
Project description:Atherosclerosis is a chronic inflammatory disease. Lesion progression is primarily mediated by cells of the monocyte/macrophage lineage. Interleukin-17A is a pro-inflammatory cytokine, which modulates immune cell trafficking and is involved inflammation in (auto)immune and infectious diseases. But the role of IL-17A still remains controversial. In the current study we investigated effects of IL-17A on advanced murine and human atherosclerosis, the common disease phenotype in clinical care. 26-weeks old apolipoprotein E-deficient (Apoe-/-) mice were fed a standard chow diet and treated either with IL-17A mAb (n=15) or irrelevant immunoglobulin (n=10) for 16 weeks. Furthermore, essential mechanisms of IL-17A in atherogenesis were studied in vitro. Inhibition of IL-17A markedly prevented atherosclerotic lesion progression (P=0.001) by reducing inflammatory burden and cellular infiltration (P=0.01) and improved lesion stability (P=0.01). In vitro experiments showed that IL-17A plays a role in chemoattractance, monocyte adhesion, sensitization of antigen-presenting cells toward pathogen-derived TLR4 ligands. Also, IL-17A induced a unique transcriptome pattern in monocyte-derived macrophages distinct from known macrophage types. Stimulation of human carotid plaque tissue ex vivo with IL-17A induced a pro-inflammatory milieu and up-regulation of molecules expressed by the IL-17A-induced macrophage subtype. We here show for the first time that functional blockade of IL-17A prevents atherosclerotic lesion progression and induces plaque stabilization in advanced lesions in Apoe-/- mice. The underlying mechanisms involve reduced inflammation and distinct effects of IL-17A on monocyte / macrophage lineage. In addition, translational experiments underline the relevance for the human system. Effects of IL-17A on human monocyte-derived macrophages were assessed (n=2 per group).
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs. Overall design: One-condition experment, gene expression of 3A6