Project description:Oligonucleotide and complementary DNA microarrays are being used to subclassify histologically similar tumours, monitor disease progress, and individualize treatment regimens. However, extracting new biological insight from high-throughput genomic studies of human diseases is a challenge, limited by difficulties in recognizing and evaluating relevant biological processes from huge quantities of experimental data. Here we present a structured network knowledge-base approach to analyse genome-wide transcriptional responses in the context of known functional interrelationships among proteins, small molecules and phenotypes. This approach was used to analyse changes in blood leukocyte gene expression patterns in human subjects receiving an inflammatory stimulus (bacterial endotoxin). We explore the known genome-wide interaction network to identify significant functional modules perturbed in response to this stimulus. Our analysis reveals that the human blood leukocyte response to acute systemic inflammation includes the transient dysregulation of leukocyte bioenergetics and modulation of translational machinery. These findings provide insight into the regulation of global leukocyte activities as they relate to innate immune system tolerance and increased susceptibility to infection in humans. Keywords: Gene expression profiling of human blood leukocytes in response to in vivo endotoxin administration.
Project description:Oligonucleotide and complementary DNA microarrays are being used to subclassify histologically similar tumours, monitor disease progress, and individualize treatment regimens. However, extracting new biological insight from high-throughput genomic studies of human diseases is a challenge, limited by difficulties in recognizing and evaluating relevant biological processes from huge quantities of experimental data. Here we present a structured network knowledge-base approach to analyse genome-wide transcriptional responses in the context of known functional interrelationships among proteins, small molecules and phenotypes. This approach was used to analyse changes in blood leukocyte gene expression patterns in human subjects receiving an inflammatory stimulus (bacterial endotoxin). We explore the known genome-wide interaction network to identify significant functional modules perturbed in response to this stimulus. Our analysis reveals that the human blood leukocyte response to acute systemic inflammation includes the transient dysregulation of leukocyte bioenergetics and modulation of translational machinery. These findings provide insight into the regulation of global leukocyte activities as they relate to innate immune system tolerance and increased susceptibility to infection in humans.
Project description:Several inflammatory diseases respond to TNFα inhibitors, implicating TNFα signaling in the pathogenesis of these conditions. Here, we set out to map the systemic genome-wide transcriptome influenced by TNFα release. We performed an intravenous endotoxin challenge in 16 healthy subjects, half of whom were pretreated with the soluble TNF receptor fusion protein, etanercept. Whole-blood leukocyte total RNA was isolated using the PAXgeneTM tube and PAXgeneTM RNA isolation system (PreAnalytiXTM, Qiagen) as described by the manufacturer. Total RNA yield and purity (260nm:280nm) were determined spectrophotometrically. The integrity of the re-suspended total RNA was determined using the RNA Nano Chip Kit on the Bioanalyzer 2100 and the 2100 Expert software (Agilent). To increase the sensitivity of our gene expression assay, the overload of globin mRNA of whole blood samples was reduced by applying the human GLOBINclear kit (Ambion/Appied Biosystems). Synthesis, amplification and purification of anti-sense RNA was performed using 300 ng of enriched mRNA per sample and the Illumina TotalPrep RNA Amplification Kit (Ambion/Applied Biosystems) following the Illumina Sentrix Array Matrix expression protocol. A total of 750 ng biotinylated cRNA was hybridized onto the HumanHT-12v3 expression BeadChips (Illumina). The BeadChips were scanned according to the protocol described in the Illumina Whole Genome Gene Expression for BeadStation Manual v3.2, Revision A using scanning software BeadScan 3.5.31. The GenomeStudio® Data Analysis Software (Illumina) was used for data collection. Missing values were imputed by using the k-nearest-neighbor algorithm (k=15). The raw scan and imputed data were read using the lumi available through Bioconductor. This was carried out using the R statistical package (version 2.10.1; R Foundation for Statistical Computing, Vienna, Austria). Quality control checks of the raw non-normalized data included visualization of the similarity matrix and hierarchical clustering analysis. Samples for one placebo-treated individual did not pass our quality control checks, and thus were removed from subsequent normalization and analysis. Total RNA isolated from a collection of human tissue-derived cell lines was used as an internal control; this sample also was omitted from subsequent data normalization. Variance stabilizing normalization (Biconductor library vsn) was applied to all other samples. All subsequent analyses were performed on vsn-transformed intensity values. This study investigated the genome-wide transcriptional response to endotoxin-induced TNF-alpha-mediated signaling in whole-blood leukocytes. Total RNA was isolated from PAXgene-treated whole blood of 16 healthy volunteers before and 4 hours after infusion of 1ng/kg E. coli lipopolysaccharide. Eight of these subjects were treated with the TNF-alpha inhibitor, etanercept.
Project description:Genome-wide gene expression was measured in peripheral blood mononuclear cells (PBMC) from healthy humans donors, four hours post stimulation of a single or double treatment of LPS and compared to untreated control PBMCs. We show that a second treatment with LPS induces endotoxin tolerance, with a transcription profile similar to that seen during alternative polarization (M2) of mononuclear cells. Microarray processing was performed by the Genome BC Microarray Platform. Total RNA obtained from PBMCs from blood from healthy humans after single treatment with LPS, two treatments with LPS, or untreated. Comparison of LPS or LPS/LPS to untreated cells shows the gene expression pattern of endotoxin tolerance.
Project description:In animal production, the use of probiotics supplements to promote animal health is increasing. The objective of this study was to assess the impact of probiotics administration on global gene expression in dairy cows. Lactating Holstein-Friesian cows (n=10) from the North Carolina Agricultural and Technical State University dairy herd were used for the study. Treatment was a 50 ml oral drench of FASTtrak microbial pack (Probiotics) (Conklin Company, Kansas City, MO) at the recommended dose in sterile endotoxin-free water or sterile endotoxin-free water only (control). This treatment was carried out for 60 days. Whole blood was collected at the beginning (Day 0) and end of the study (Day 60) for microarray analysis. We employed microarray expression profiling as a discovery platform to identify genes with potential association with probiotics supplementation in cows. Gene expression analysis identified 10,859 differentially expressed genes- 1168 upregulated genes and 9691 downregulated gene. Results for pathway analysis showed significant pathways associated with innate immunity such as the Toll-like receptor (TLR) pathway, inflammation response and Wingless (Wnt) signaling pathway. Real-time PCR was used to validate the expression of the Wnt signaling pathway and immune response genes. Probiotic treatment impacted global gene expression, and particularly, the expression of immune response and Wnt signaling pathway genes. Oral administration of probiotics to dairy cows impacts global gene expression and particularly the expression of innate immune genes in dairy cows.
Project description:Genome-wide DNA methylation profile of peripheral blood leukocyte samples taken from patients under clozapine treatment. The Infinium MethylationEPIC BeadChip was analyzed to obtain DNA methylation profiles in samples from 31 patients with psychotic disorders under treatment with clozapine and 56 patients with psychiatric disorders naïve to psychopharmacological treatment
Project description:Rationale: Obstructive sleep apnea (OSA) has been associated with a number of chronic disorders that may improve with effective therapy. However, the molecular pathways affected by continuous positive airway pressure (CPAP) treatment are largely unknown. We sought to assess the system-wide consequences of CPAP therapy by transcriptionally profiling peripheral blood leukocytes (PBLs). Methods: Subjects diagnosed with severe OSA were treated with CPAP, and whole-genome expression measurement of PBLs was performed at baseline and following therapy. We used Gene Set Enrichment Analysis (GSEA) to identify gene sets that were differentially enriched. Network analysis was then applied to identify key drivers of pathways influenced by CPAP. Results: 18 subjects with severe OSA (apnea hypopnea index ≥ 30 events/hour) underwent CPAP therapy and microarray analysis of their PBLs. Treatment with CPAP improved AHI, daytime sleepiness and blood pressure but did not affect anthropometric measures. GSEA revealed a number of enriched gene sets, many of which were involved in neoplastic processes and displayed down-regulated expression patterns in response to CPAP. Network analysis identified several densely connected genes that are important modulators of cancer and tumor growth. Conclusions: Effective therapy of OSA with CPAP is associated with alterations in circulating leukocyte gene expression. Functional enrichment and network analyses highlighted transcriptional suppression in cancer-related pathways suggesting potentially novel mechanisms linking OSA with neoplastic signatures. Total RNA from peripheral blood leukocytes of 18 subjects with severe sleep apnea at baseline and after effective CPAP therapy was hybridized to 36 Affymetrix Genechip Human Gene 1.0 ST microarrays
Project description:The objective of the study was to utilize DNA methylation to quantify human leukocyte subsets in human blood. This file contains data from an Illumina custom VeraCode GGMA microarray for human leukocyte subtypes (purified from whole blood samples via magnetic activated cell sorting (MACS) and purity confirmed by flourescence activated cell sorting (FACS)) as well as for complex mixtures of DNA from those samples, and for human whole blood samples.