Response of Atf3-/- and WT BMDMs to treatment with LPS for 4 h
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE32574 | GEO | 2012/03/23
SECONDARY ACCESSION(S): PRJNA147101
REPOSITORIES: GEO
Similar Datasets
Project description:Atherosclerosis is a chronic inflammatory disease characterized by the accumulation of lipid-loaded macrophages in the arterial wall. Intimal macrophages internalize modified lipoproteins such as oxidized LDL (oxLDL) through scavenger receptors, leading to storage of excess cholesteryl esters in lipid bodies and a "foam cell" phenotype. In addition, stimulation of macrophage Toll-like receptors (TLRs) has been shown to promote lipid body proliferation. We investigated the possibility that there are transcriptional regulators that are common to both pathways for stimulating foam cell formation (modified lipoproteins and TLR stimulation), and identified the transcription factor ATF3 as a candidate regulator. In this specific microarray study, we re-analyzed a subset of the data from a 2006 microarray experiment (Gilchrist et al., Nature, 441:173-178, 2006) in which wild-type and Atf3-/- murine macrophages were stimulated with LPS. The goal of this analysis was to identify genes whose LPS responses are significantly affected by loss of ATF3 in macrophages, using up-to-date genome annotations. The raw microarray data files included in this submission were originally released to the public as a part of a larger microarray dataset that accompanied the Gilchrist et al. study (ArrayExpress accession # E-TABM-102). These data were re-analyzed using the CustomCDF v13 ENSG probesets as a part of a transcriptomic study of the response of macrophages to stimuli, including LPS, that induce foam cell formation (see GSE32358 and GSE32359). In the Gilchrist study, the experiment design was as follows: Female mice of the indicated strains were sacrificed at 8-12 weeks of age, and macrophages were derived from the femoral bone marrow using rhM-CSF. On day six, macrophages were plated and LPS introduced into the medium as indicated. After four hours, RNA was isolated using Trizol. Labeled cRNA derived from the RNA samples was hybridized to Affymetrix Mouse Genome 430 2.0 GeneChips. For the current study, probe-level instensity data were re-processed using gene-level probesets from the CustomCDF project (ENSG, v13), and are in log2 scale.
2012-03-23 | E-GEOD-32574 | biostudies-arrayexpress
Project description:Atherosclerosis is a chronic inflammatory disease characterized by the accumulation of lipid-loaded macrophages in the arterial wall. Intimal macrophages internalize modified lipoproteins such as oxidized LDL (oxLDL) through scavenger receptors, leading to storage of excess cholesteryl esters in lipid bodies and a "foam cell" phenotype. In addition, stimulation of macrophage Toll-like receptors (TLRs) has been shown to promote lipid body proliferation. We investigated the possibility that there are transcriptional regulators that are common to both pathways for stimulating foam cell formation (modified lipoproteins and TLR stimulation), and identified the transcription factor ATF3 as a candidate regulator. In this specific microarray experiment, we studied the effect of genetic knockout of ATF3 on the transcriptional response of macrophages to oxLDL. Murine bone marrow-derived macrophages from two different mouse strains (Atf3-/- and WT) were incubated in the presence or absence of oxidized low-density lipoprotein (oxLDL), and then transcriptionally profiled using the Affymetrix Mouse Exon Array 1.0 ST. The goal was to study the pattern of differential expression between WT and Atf3-/- strains, in oxLDL-induced foam cells and in non-foamy control cells, to identify cellular pathways that may be dysregulated under loss of the transcription factor ATF3 in macrophage foam cells. Twelve female mice (six Atf3-/-, and six WT control mice) were sacrificed at 8-12 weeks of age, and macrophages were derived from the femoral bone marrow using rhM-CSF. oxLDL was introduced into the medium for six samples (3 WT and 3 Atf3-/-) at 25 ug/mL on day seven, and after 24 h of incubation, RNA was isolated using Trizol. Labeled cRNA derived from the RNA samples was hybridized to Affymetrix Mouse Exon Array 1.0 ST GeneChips. Microarray data were processed using transcript-level probesets, and are in log2 scale.
2012-03-23 | E-GEOD-32358 | biostudies-arrayexpress
Project description:Atherosclerosis is a chronic inflammatory disease characterized by the accumulation of lipid-loaded macrophages in the arterial wall. Intimal macrophages internalize modified lipoproteins such as oxidized LDL (oxLDL) through scavenger receptors, leading to storage of excess cholesteryl esters in lipid bodies and a "foam cell" phenotype. In addition, stimulation of macrophage Toll-like receptors (TLRs) has been shown to promote lipid body proliferation. We investigated the possibility that there are transcriptional regulators that are common to both pathways for stimulating foam cell formation (modified lipoproteins and TLR stimulation), and identified the transcription factor ATF3 as a candidate regulator. In this specific microarray experiment, we studied the transcriptional response of murine macrophages to stimulation with the TLR4 agonist, LPS. Bone marrow-derived macrophages from C57BL/6J mice were incubated in the presence or absence of LPS for 4 h, and then transcriptionally profiled using the Affymetrix Mouse Exon Array 1.0 ST. The goal was to study the pattern of transcript-level differential expression between the unstimulated and LPS-stimulated cells.
2012-03-23 | GSE32359 | GEO
Project description:Atherosclerosis is a chronic inflammatory disease characterized by the accumulation of lipid-loaded macrophages in the arterial wall. Intimal macrophages internalize modified lipoproteins such as oxidized LDL (oxLDL) through scavenger receptors, leading to storage of excess cholesteryl esters in lipid bodies and a "foam cell" phenotype. In addition, stimulation of macrophage Toll-like receptors (TLRs) has been shown to promote lipid body proliferation. We investigated the possibility that there are transcriptional regulators that are common to both pathways for stimulating foam cell formation (modified lipoproteins and TLR stimulation), and identified the transcription factor ATF3 as a candidate regulator. In this specific microarray experiment, we studied the effect of genetic knockout of ATF3 on the transcriptional response of macrophages to oxLDL. Murine bone marrow-derived macrophages from two different mouse strains (Atf3-/- and WT) were incubated in the presence or absence of oxidized low-density lipoprotein (oxLDL), and then transcriptionally profiled using the Affymetrix Mouse Exon Array 1.0 ST. The goal was to study the pattern of differential expression between WT and Atf3-/- strains, in oxLDL-induced foam cells and in non-foamy control cells, to identify cellular pathways that may be dysregulated under loss of the transcription factor ATF3 in macrophage foam cells.
2012-03-23 | GSE32358 | GEO
Project description:Atherosclerosis is a chronic inflammatory disease characterized by the accumulation of lipid-loaded macrophages in the arterial wall. Intimal macrophages internalize modified lipoproteins such as oxidized LDL (oxLDL) through scavenger receptors, leading to storage of excess cholesteryl esters in lipid bodies and a "foam cell" phenotype. In addition, stimulation of macrophage Toll-like receptors (TLRs) has been shown to promote lipid body proliferation. We investigated the possibility that there are transcriptional regulators that are common to both pathways for stimulating foam cell formation (modified lipoproteins and TLR stimulation), and identified the transcription factor ATF3 as a candidate regulator. In this specific microarray experiment, we studied the transcriptional response of murine macrophages to stimulation with the TLR4 agonist, LPS. Bone marrow-derived macrophages from C57BL/6J mice were incubated in the presence or absence of LPS for 4 h, and then transcriptionally profiled using the Affymetrix Mouse Exon Array 1.0 ST. The goal was to study the pattern of transcript-level differential expression between the unstimulated and LPS-stimulated cells. Three female mice (strain C57BL/6J) were sacrificed at 8-12 weeks of age, and macrophages were derived from the femoral bone marrow using rhM-CSF. On day six, macrophages were divided into two treatment groups per animal, for a total of six samples. LPS was introduced into the medium for three samples (one from each animal) at 10 ng/mL on day seven, and after 4 h of incubation, RNA was isolated using Trizol. Labeled cRNA derived from the RNA samples was hybridized to Affymetrix Mouse Exon Array 1.0 ST GeneChips. Microarray data were processed using transcript-level probesets, and are in log2 scale.
2012-03-23 | E-GEOD-32359 | biostudies-arrayexpress
Project description:The accumulation of lipid-laden macrophages (foam cells) in the arterial wall is a crucial early step in atherosclerotic plaque development. Modified low-density lipoprotein (LDL) is the primary cholesterol source for foam cells, taken up in an unregulated manner through scavenger receptors. This type of cells exhibit reduced migratory capacity while producing elevated levels of pro-inflammatory cytokines, thereby promoting inflammation and plaque progression. Still our understanding of the transcriptomic changes during macrophage-to-foam cell conversion remains limited. In this experiment, we aimed to identify genes responsible for the accumulation of cholesterol in human monocyte-derived macrophages exposed to modified and native LDL. The monocyte samples collected from healthy individuals were purified and exposed to modified and native LDLs obtained from plasm of atherosclerotic patients. RNA extracted after 24h of incubation was sequenced with polyA selection. The resulting data was normalised with limma and undergone DEG analysis followed by upstream analysis workflow with TRANSPATH and TRANSFAC databases to discover master regulator molecules.
2023-08-14 | E-MTAB-13261 | biostudies-arrayexpress
Project description:Lipoprotein lipase (LPL) is an extracellular lipase that preferentially hydrolyses triglycerides in triglyceride-rich lipoproteins within the circulation. LPL expression in macrophages contributes to atherosclerosis. In addition, the hydrolysis products liberated from lipoprotein lipids by LPL causes lipid accumulation and impairs cholesterol efflux ability in macrophages. However, the effects of LPL hydrolysis products in modulating the transcript profiles within macrophages and their roles in foam cell formation are not completely understood. We performed microarray analyses on THP-1 macrophages incubated with LPL hydrolysis products to identify differentially expressed genes.
2017-02-15 | GSE84791 | GEO
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).
2015-07-23 | E-GEOD-70126 | biostudies-arrayexpress
Project description:Poly-ethylene-glycol (PEG)-based nanoparticles (NPs) - including cylindrical micelles (CNPs), spherical micelles (SNPs), and PEGylated liposomes (PLs) - are hypothesized to be cleared in vivo by opsonization followed by liver macrophage phagocytosis. This hypothesis has been used to explain the rapid and significant localization of NPs to the liver after administration into the mammalian vasculature. Here, we show that the opsonization-phagocytosis nexus is not the major factor driving PEG-NP – macrophage interactions. First, mouse and human blood proteins had insignificant affinity for PEG-NPs. Second, PEG-NPs bound macrophages in the absence of serum proteins. Third, lipoproteins blocked PEG-NP binding to macrophages. Because of these findings, we tested the postulate that PEG-NPs bind (apo)lipoprotein receptors. Indeed, PEG-NPs triggered an in vitro macrophage transcription program that was similar to that triggered by lipoproteins and different from that triggered by lipopolysaccharide (LPS) and group A Streptococcus. Unlike LPS and pathogens, PLs did not increase transcripts involved in phagocytosis or inflammation. High-density lipoprotein (HDL) and SNPs triggered remarkably similar mouse bone-marrow-derived macrophage transcription programs. Unlike opsonized pathogens, CNPs, SNPs, and PLs lowered macrophage autophagosome levels and either reduced or did not increase the secretion of key macrophage pro-inflammatory cytokines and chemokines. Thus, the sequential opsonization and phagocytosis process is likely a minor aspect of PEG-NP – macrophage interactions. Instead, PEG-NP interactions with (apo)lipoprotein and scavenger receptors appear to be a strong driving force for PEG-NP – macrophage binding, entry, and downstream effects. We hypothesize that the high presence of these receptors on liver macrophages and on liver sinusoidal endothelial cells is the reason PEG-NPs localize rapidly and strongly to the liver. To investigate the response of macrophages to nanoparticles, we incubated PEGylated liposomes (PLs), spherical nanoparticles (SNPs), high-density lipoproteins (HDL), low-density lipoproteins (LDL), Group A Streptococcus pathogens (JRS4), and lipopolysaccharide (LPS) with RAW264.7 and primary bone-marrow derived mouse macrophages
2023-12-27 | GSE249596 | GEO
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-β 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-β 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.
2015-07-23 | GSE70126 | GEO