Objective: 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 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 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 SamplesJuvenile idiopathic arthritis (JIA) is the most common chronic childhood rheumatic disease in the Western world. To identify novel JIA predisposing loci, a genome-wide association study (GWAS) in 814 Caucasian JIA cases and 3058 Caucasian controls was completed. After adjusting for the most significant HLA associations, the strongest novel associations included rs6479891 (10q21, odds ratio (OR)=1.59, P=1.3x10-8) and rs10761747 (OR=1.34, P=4.0x10-5) within JMJD1C; rs12719740 (15q26, OR=1.47, P=3.3x10-7) near FAM169B; rs4688011 (3q13, OR=1.33, P=1.1x10-4) within C3orf1 and rs4254850 (4q31, OR=0.85, P=7.8x10-3) near IL15. Eleven SNPs were genotyped in Caucasian replication cohorts (1744 cases, 7010 controls) and meta-analysis continued to provide evidence for association with three of the SNPs (rs6479891, P=4.3x10-5; rs12719740, P=5.2x10-4; rs4688011, P=3.6x10-7). Analysis of expression data from 68 JIA cases and 23 controls overlapping in the GWAS cohort1 and published lymphoblastoid cell lines (LCL)2 showed cis eQTL associations for JMJD1C SNPs (P=0.01 and P=1.6x10-6, respectively), and the C3orf1 SNP (P=5.7x10-6).
Genome-wide association analysis of juvenile idiopathic arthritis identifies a new susceptibility locus at chromosomal region 3q13.
Sex, Specimen part, Disease, Disease stage, 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 SamplesFamilial hemophagocytic lymphohistiocytosis (FHL) is a rare, genetically heterogeneous autosomal recessive immune disorder that results when the critical regulatory pathways that mediate immune defense mechanisms and the natural termination of immune/inflammatory responses are disrupted or overwhelmed. In order to advance the understanding of FHL, we performed gene expression profiling of peripheral blood mononuclear cells (PBMCs) from 11 children with untreated FHL. Total RNA was isolated and gene expression levels were determined using microarray analysis. Comparisons between patients with FHL and normal pediatric controls (n = 30) identified 915 down-regulated and 550 up-regulated genes with 2.5-fold difference in expression (P = 0.05). The expression of genes associated with natural killer cell functions, innate and adaptive immune responses, pro-apoptotic proteins, and B- and T-cell differentiation were down-regulated in patients with FHL. Genes associated with the canonical pathways of IL-6, IL-10 IL-1, IL-8, TREM1, LXR/RXR activation, and PPAR signaling and genes encoding of anti-apoptotic proteins were overexpressed in patients with FHL. This, first study of genome-wide expression profiling in children with FHL demonstrates the complexity of gene expression patterns, which underly the immunobiology of FHL.
Gene expression profiling of peripheral blood mononuclear cells from children with active hemophagocytic lymphohistiocytosis.
Specimen part
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 SamplesThis SuperSeries is composed of the SubSeries listed below.
No associated publication
Specimen part, Cell line
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
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