The activation profiles of macrophages under different immune and inflammatory conditions have generated great interest. LPS, in particular, is a commonly used in vitro model of infection and inflammation studies in macrophages. We have used gene expression microarrays to define the effects of each of three variables; LPS dose, LPS vs. interferons beta and gamma, and genetic background on the transcriptional response of mouse bone marrow-derived macrophages
Analysis of the transcriptional networks underpinning the activation of murine macrophages by inflammatory mediators.
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View SamplesTemporal changes of gene expression from 1-wk- to 5-wk-old rat in kidney and lung, and the effect of prior growth inhibition on these genetic changes.
Coordinated postnatal down-regulation of multiple growth-promoting genes: evidence for a genetic program limiting organ growth.
Age, Specimen part
View SamplesAnalysis of gene expression in two large schizophrenia cohorts identifies multiple changes associated with nerve terminal function.
Analysis of gene expression in two large schizophrenia cohorts identifies multiple changes associated with nerve terminal function.
Sex, Age
View SamplesTranscriptional analysis of the superior temporal cortex (BA22) in schizophrenia: Pathway insight into disease pathology and drug development
Transcription and pathway analysis of the superior temporal cortex and anterior prefrontal cortex in schizophrenia.
Sex, Age, Specimen part, Disease, Disease stage
View SamplesIFNg is a pro-inflammatory and pro-atherogenic cytokine that leads to macrophage activation. Adenosine has well-documented anti-inflammatory properties. We used microarrays to compare the global gene expression profile in mouse macrophages stimulated with IFNg alone and those cells treated with IFNg and adenosine.
Adenosine blocks IFN-gamma-induced phosphorylation of STAT1 on serine 727 to reduce macrophage activation.
No sample metadata fields
View SamplesTemporal changes of gene expression from 1-wk- to 4-wk and 8-wk-old mouse in heart, kidney and lung. Mammalian somatic growth is rapid in early postnatal life but then slows and eventually ceases in multiple tissues. We hypothesized that there exists a postnatal gene expression program that is common to multiple tissues and is responsible for this coordinate growth deceleration. Consistent with this hypothesis, microarray analysis identified >1600 genes that were regulated with age coordinately in kidney, lung, and heart of juvenile mice, including many genes that regulate proliferation. As examples, we focused on three growth-promoting genes, Igf2, Mest, and Peg3, that were markedly downregulated with age. We conclude that there exists an extensive genetic program occurring during postnatal life. Many of the involved genes are regulated coordinately in multiple organs, including many genes that regulate cell proliferation. At least some of these are themselves apparently regulated by growth, suggesting that, in the embryo, a gene expression pattern is established that allows for rapid somatic growth of multiple tissues but then, during postnatal life, this growth leads to negative-feedback changes in gene expression that in turn slow and eventually halt somatic growth, thus imposing a fundamental limit on adult body size.
An extensive genetic program occurring during postnatal growth in multiple tissues.
Sex, Age, Specimen part
View SamplesThe growth in popularity of RNA expression microarrays has been accompanied by concerns about the reliability of the data especially when comparing between different platforms. Here we present an evaluation of the reproducibility of microarray results using two platforms, Affymetrix GeneChips and Illumina BeadArrays. The study design is based on a dilution series of two human tissues (blood and placenta), tested in duplicate on each platform. By a variety of measures the two platforms yielded data of similar quality and properties. The results of a comparison between the platforms indicate very high agreement, particularly for genes which are predicted to be differentially expressed between the two tissues. Agreement was strongly correlated with the level of expression of a gene. Concordance was also improved when probes on the two platforms could be identified as being likely to target the same set of transcripts of a given gene. These results shed light on the causes or failures of agreement across microarray platforms. The set of probes we found to be most highly reproducible can be used by others to help increase confidence in analyses of other data sets using these platforms.
Experimental comparison and cross-validation of the Affymetrix and Illumina gene expression analysis platforms.
No sample metadata fields
View SamplesIn the analysis of peripheral blood gene expression, timely processing of samples is essential to ensure that measurements reflect in vivo biology, rather than ex vivo sample processing variables. The effect of processing delays on global gene expression patterns in peripheral blood mononuclear cells (PBMC) was assessed by isolating and stabilizing PBMC-derived RNA from three individuals either immediately after phlebotomy or following a 4 hour delay. RNA was labeled using NuGEN Ovation labeling and probed using the Affymetrix HG U133plus 2.0 GeneChip. Comparison of gene expression levels (p<0.05 and 2-fold expression change) identified 327 probe sets representing genes with increased expression and 46 indicating decreased expression after 4 hours. The trends in expression patterns associated with delayed processing were also apparent in an independent set of 276 arrays of RNA from human PBMC samples with varying processing times. These data indicate that the time between sample acquisition, initiation of processing, and when the RNA is stabilized should be a prime consideration when designing protocols for translational studies involving PBMC gene expression analysis.
Gene Expression Profiles from Peripheral Blood Mononuclear Cells Are Sensitive to Short Processing Delays.
Specimen part, Subject, Time
View SamplesOBJECTIVE: To determine whether macrophages, a type of cell implicated in the pathogenesis of ankylosing spondylitis (AS), exhibit a characteristic gene expression pattern. METHODS: Macrophages were derived from the peripheral blood of 8 AS patients (median disease duration 13 years [range <1-43 years]) and 9 healthy control subjects over 7 days with the use of granulocyte-macrophage colony-stimulating factor. Cells were stimulated for 24 hours with interferon-gamma (IFNgamma; 100 units/ml), were left untreated for 24 hours, or were treated for 3 hours with lipopolysaccharide (LPS; 10 ng/ml). RNA was isolated and examined by microarray and real-time quantitative reverse transcription-polymerase chain reaction analysis. RESULTS: Microarray analysis revealed 198 probe sets detecting the differential expression of 141 unique genes in untreated macrophages from AS patients compared with healthy controls. Clustering and principal components analysis clearly distinguished AS patients and controls. Of the differentially expressed genes, 78 (55%) were IFN-regulated, and their relative expression indicated a reverse IFN signature in AS patient macrophages, where IFNgamma-up-regulated genes were underexpressed and down-regulated genes were overexpressed. Treatment of macrophages with exogenous IFNgamma normalized the expression of these genes between patients and controls. In addition, the messenger RNA encoded by the IFNgamma gene was approximately 2-fold lower in AS patient macrophages at baseline (P = 0.004) and was poorly responsive to LPS (P = 0.018), as compared with healthy controls. CONCLUSIONS: Our findings reveal consistent differences in gene expression in macrophages from AS patients, with evidence of a striking reverse IFN signature. Together with poor expression and responsiveness of the IFNgamma gene, these results suggest that there may be a relative defect in IFNgamma gene regulation, with autocrine consequences and implications for disease pathogenesis.
Gene expression analysis of macrophages derived from ankylosing spondylitis patients reveals interferon-gamma dysregulation.
No sample metadata fields
View SamplesObjective. To identify gene expression differences in peripheral blood from patients with early and late onset juvenile idiopathic arthritis (JIA).
Biologic similarities based on age at onset in oligoarticular and polyarticular subtypes of juvenile idiopathic arthritis.
Sex, Specimen part, Race
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