In 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.
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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
View SamplesObjective. Previous observations suggest that active systemic juvenile idiopathic arthritis (sJIA) is associated with a prominent erythropoiesis gene expression signature. The aim of this study was to determine the association of this signature with peripheral blood mononuclear cell (PBMC) subpopulations and its specificity for sJIA as compared to related conditions.
Immature cell populations and an erythropoiesis gene-expression signature in systemic juvenile idiopathic arthritis: implications for pathogenesis.
Sex, Specimen part, Race
View SamplesBiotinylated cRNA was synthesized from total RNA (Enzo; Farmingdale, NY) and processed according to the Affymetrix GeneChip Expression Analysis Technical Manual (Affymetrix; Santa Clara, CA). 57 samples: 5 pauciarticular PBMC, 15 polyarticular PBMC, 11 control PMBC, 6 JSpA PBMC, 5 pauciarticular SFMC, 10 polyarticular PBMC, 5 JSpA SFMC classified by course.
Gene expression in juvenile arthritis and spondyloarthropathy: pro-angiogenic ELR+ chemokine genes relate to course of arthritis.
No sample metadata fields
View SamplesSystemic Juvenile Idiopathic Arthritis (sJIA) has been strongly associated with macrophage activation syndrome (MAS). To better understand the pathogenesid of sJIA and to facilitate the search for MAS biomarkers, we examine gene expression profiles in untreated new onset sJIA.
Gene expression profiling of peripheral blood from patients with untreated new-onset systemic juvenile idiopathic arthritis reveals molecular heterogeneity that may predict macrophage activation syndrome.
No sample metadata fields
View SamplesObjective. Microarray analysis was used to determine whether children with recent onset polyarticular juvenile idiopathic arthritis (JIA) exhibit biologically or clinically informative gene expression signatures in peripheral blood mononuclear cells (PBMC). Methods. Peripheral blood samples were obtained from 59 healthy children and 61 children with polyarticular JIA prior to treatment with second-line medications, such as methotrexate or biological agents. RNA was purified from Ficoll-isolated mononuclear cells, fluorescently labeled and then hybridized to Affymetrix U133 Plus 2.0 GeneChips. Data were analyzed using ANOVA at a 5% false discovery rate threshold after Robust Multi-Array Average pre-processing and Distance Weighted Discrimination normalization. Results. Initial analysis revealed 873 probe sets for genes that were differentially expressed between polyarticular JIA and controls. Hierarchical clustering of these probe sets distinguished three subgroups within polyarticular JIA. Prototypical subjects within each subgroup were identified and used to define subgroup-specific gene expression signatures. One of these signatures was associated with monocyte markers, another with transforming growth factor-beta-inducible genes, and a third with immediate-early genes. Correlation of these gene expression signatures with clinical and biological features of JIA subgroups suggests direct relevance to aspects of disease activity and supports the division of polyarticular JIA into distinct subsets. Conclusions. PBMC gene expression signatures in recent onset polyarticular JIA reflect discrete disease processes and offer a molecular classification of disease.
Gene expression signatures in polyarticular juvenile idiopathic arthritis demonstrate disease heterogeneity and offer a molecular classification of disease subsets.
Sex, Specimen part, Race
View SamplesObjective: A multi-center study of recent onset juvenile idiopathic arthritis (JIA) subjects prior to treatment with DMARDS or biologics was undertaken to identify peripheral blood gene expression differences between JIA subclasses and controls. Methods: PBMC from 59 healthy children and 136 JIA subjects (28 enthesitis-related arthritis[ERA], 42 persistent oligoarthritis, 45 RF- polyarthritis, and 21 systemic) were isolated on Ficoll. Poly-A RNA was labeled using NuGEN Ovation and gene expression profiles were obtained using Affymetrix HG-U133 plus 2.0 Arrays. Results: 9,501 differentially expressed probe sets were identified among JIA subtypes and controls (ANOVA, FDR 5%). Specifically, 193, 1036, 873 and 7595 probe sets were different between controls and ERA, persistent oligoarthritis, RF- polyarthritis and systemic JIA samples respectively. In persistent oligoarthritis, RF- polyarthritis and systemic JIA subtypes, up-regulation of gene associated with IL-10 signaling was prominent. A hemoglobin cluster was identified that was under-expressed in ERA patients but over-expressed in systemic JIA. The influence of JAK/STAT, ERK/MAPK, IL-2 and B cell receptor signaling pathways was evident in persistent oligoarthritis. In systemic JIA, up regulation of innate immune pathways, including IL-6, TLR/IL1R, and PPAR signaling were noted, along with down regulation of gene networks related to NK and T cells. Complement and coagulation pathways were up-regulated in systemic JIA with a subset of these components differentially-expressed in the other three subtypes. Conclusions: Expression analysis identified differentially expressed genes in PBMCs between subclasses of JIA early in disease and controls, thus providing evidence for immunobiologic differences between these forms of childhood arthritis.
Subtype-specific peripheral blood gene expression profiles in recent-onset juvenile idiopathic arthritis.
Sex, Specimen part, Race
View SamplesHere we analyse single cell transcriptome profiles of EZH2-deficient human embroynic stem cells Overall design: Single cell transcriptome (mRNA-Seq) from Ezh2-/- (Null) and EZH2+/+ (WT) human ESC
Deletion of the Polycomb-Group Protein EZH2 Leads to Compromised Self-Renewal and Differentiation Defects in Human Embryonic Stem Cells.
Specimen part, Subject
View SamplesAcute lung injury (ALI) or acute respiratory distress syndrome (ARDS) is a severe syndrome affecting more than 200,000 patients annually in the U.S. New studies are needed to understand the biological and clinical mechanisms that impair alveolar epithelial function. Also, innovative therapies are needed for the resolution of pulmonary edema in ARDS. We and other investigators have reported that bone marrow derived mesenchymal stem cells (MSCs) are effective in preclinical models of ALI due to their ability to secrete several paracrine factors that can regulate lung endothelial and epithelial permeability, including growth factors, anti-inflammatory cytokines, and antimicrobial peptides. So in this study we will test the therapeutic value of human MSCs in an in vitro model of acute lung injury induced by pro-inflammatory cytokines.
Human Mesenchymal Stem (Stromal) Cells Promote the Resolution of Acute Lung Injury in Part through Lipoxin A4.
Specimen part
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