Project description:We report the C/EBP beta transcription factor binding landscape in human macrophages and oxLDL-induced foam cells ChIP-seq for C/EBP beta binding was performed in human macrophages and oxLDL induced-foam cells with quadruple biological replicates
Project description:Background: Cardiovascular diseases remain the leading cause of morbidity and mortality worldwide, most of which are caused by atherosclerosis. Discerning processes that participate in macrophage-to-foam cell formation are critical for understanding the basic mechanisms underlying atherosclerosis. To explore the molecular mechanisms of foam cell formation, the differentially expressed proteins were identified. Methods: In this paper, human monocytes, macrophage colony-stimulating factor induced macrophages, and oxidized low-density lipoprotein induced foam cells were cultured, and tandem mass tag (TMT) labeling combined with mass spectrometry (MS) were performed to find associations between foam cell transformation and proteome profiles. Results: Totally, 5146 quantifiable proteins were identified, among which 1515 and 182 differentially expressed proteins (DEPs) were found in macrophage/monocyte and foam cell/macrophage, respectively, using a cutoff of 1.5-fold change. Subcellular localization analysis revealed that downregulated DEPs of macrophages/monocytes were mostly located in the nucleus and upregulated DEPs of foam cells/macrophages mostly located in the plasma membrane and extracellular. Functional analysis of DEPs demonstrated that cholesterol metabolism related proteins were upregulated in foam cells, whereas the immune response-related proteins were downregulated in foam cells. The protein-interaction network showed that the DEPs with the highest interaction intensity between macrophages and foam cells were mainly concentrated in lysosomes and the endoplasmic reticulum. Conclusions: This study for the first time to perform quantitative proteomic investigation by TMT labeling and LC-MS/MS to identify differentially expressed proteins in human monocyte, macrophage, and foam cell. The results confirmed cholesterol metabolism was upregulated in foam cells, while immune response was suppressed, which suggested that foam cells were not the population that promote inflammation. In addition, KEGG enrichment analysis and protein-protein interaction indicated that the differentially expressed proteins locating in the endoplasmic reticulum and lysosomes may be key targets to regulate foam cell formation. These data provide a basis for identifying the potential proteins associated with the molecular mechanism involved in the transformation of macrophages to foam cells.
Project description:Foam cells were one of the hallmarks of atherosclerosis, and microRNAs (miRNAs) played an important role in the formation of foam cells. In order to explore the roles of miRNA in the formation of foam cells, In the present study, to understand the molecular mechanisms of miRNAs involved in AS, we provide insights into the genome-wide dynamic profiles of miRNAs by using high-throughput sequencing technology.
Project description:We report the enhancer landscape in primary human macrophages and foam cells using ChIP-seq for the H3K27ac histone mark CD14+ monocytes were isolated from the blood of 2 healthy male volunteers. Monocytes were differentiated into macrophages by culture for 7 days with 50ng/ml macrophage colony stimulating factor and then treated for 48 hours with either oxidized low density lipoprotein (oxLDL) to induce foam cell formation or with a control buffer that lacked oxLDL. The resulting 4 samples were then subjected to ChIP-seq for H3K27ac.
Project description:We report the open chromatin landscape in primary human macrophages and foam cells using FAIRE-seq CD14+ monocytes were isolated from the blood of 3 healthy volunteers. Monocytes were differentiated into macrophages by culture for 7 days with 50ng/ml macrophage colony stimulating factor and then treated for 48 hours with either oxidized low density lipoprotein (oxLDL) to induce foam cell formation or with a control buffer that lacked oxLDL. The resulting six samples were then subjected to FAIRE-seq using an established protocol (Simon JM, Giresi PG, Davis IJ, Lieb JD. Using formaldehyde-assisted isolation of regulatory elements (FAIRE) to isolate active regulatory DNA. Nature protocols 2012;7:256-67).
Project description:In atherosclerosis, several immune cells are involved in plaque formation. Foam cell formation is a major cellular process in atherosclerotic lesion. It is important to understand which cells participate in foam cell formation. To characterize the immune cells and foam cells in atherosclerotic aorta, we performed single cell RNA sequencing of aortic CD45+ leukocytes from Ldlr-/- mice and foamy cells from ApoE-/- mice. The single cell RNA-seq analyses revealed the heterogeneity of aortic macrophages and foam cells in atherosclerotic aorta.
Project description:Formation of foam cell macrophages (FCMs), which sequester extracellular modified lipids, is a key event in atherosclerosis. How lipid loading affects macrophage phenotype is controversial, with evidence suggesting either pro- or anti-inflammatory consequences. To investigate this further, we compared the transcriptomes of foamy and non-foamy macrophages (NFMs) that accumulate in the subcutaneous granulomas of fed-fat ApoE null mice and normal chow fed wild-type mice in vivo. Consistent with previous studies, LXR/RXR pathway genes were significantly over-represented among the genes up-regulated in foam cell macrophages. Unexpectedly, the hepatic fibrosis pathway, associated with platelet derived growth factor and transforming growth factor-? action, was also over-represented. Several collagen polypeptides and proteoglycan core proteins as well as connective tissue growth factor and fibrosis-related FOS and JUN transcription factors were up-regulated in foam cell macrophages. Increased expression of several of these genes was confirmed at the protein level in foam cell macrophages from subcutaneous granulomas and in atherosclerotic plaques. Moreover, phosphorylation and nuclear translocation of SMAD2, which is downstream of several transforming growth factor-? family members, was also detected in foam cell macrophages. We conclude that foam cell formation in vivo leads to a pro-fibrotic macrophage phenotype, which could contribute to plaque stability, especially in early lesions that have few vascular smooth muscle cells. Samples (n=4/group): Foam cell macrophages (FCM) isolated from inflammatory sponges placed in ApoE null mice fed a high-fat diet (n=4), non-foamy macrophages (NFM) isolated from inflammatory sponges placed in control mice fed a normal diet (n=4).