In E. coli the phosphate homeostasis is regulated by the Pst system and the two-component system PhoB/R. Pathogens like E. coli O157:H7 are responsible for many outbreaks and can be found and survive in poor inorganic phosphate (Pi) environments.
PhoB activates Escherichia coli O157:H7 virulence factors in response to inorganic phosphate limitation.
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View SamplesChronic lymphocytic leukemia (CLL) is a biologically and clinically heterogeneous disease. The somatic hypermutation status of the immunoglobulin heavy chain variable (IGHV) genes has been identified as one of the most robust prognostic markers in CLL. Patients with unmutated IGHV status (U-CLL) typically experience an inferior outcome compared to those whose clones express mutated IGHV genes (M-CLL). We conducted a genome-wide DNA methylation analysis in CD19+ B-cells from a group of 43 CLL patients using reduced representation bisulfite sequencing (RRBS). Using base-pair resolution methylation sequencing, 2323 differentially methylated regions between CLL and normal B-cells (CLL-specific DMRs) and 569 between M-CLL and U-CLL samples (IGHV-specific DMRs) were identified in the CLL genomes. The IGHV-specific DMRs are mostly unique when compared to the CLL-specific DMRs. Less than 10% of the IGHV-specific DMRs are located in promoter regions; however, more than half of these overlap with known DNase I hypersensitive sites, enhancer regions marked by histone modification (H3K4Me1 and H3K27Ac), and transcription factor binding sites in the ENCODE datasets, which indicates that these DMRs contain regulatory sequences. Distinctive DNA methylation patterns were observed in M-CLL and U-CLL samples. Overall, U-CLL was found to contain 50% more hypermethylated regions than M-CLL samples. The hypermethylated loci observed in the U-CLL samples also appear to be hypermethylated in normal naïve B-cells as compared memory B-cells, suggesting that M-CLL and U-CLL differ in differentiation status corresponding to normal B-cell differentiation stages. RNA-seq analysis performed using matched samples (n=34), in which both DNA methylation and gene expression data were available, demonstrated excellent correlation between DNA methylation and gene expression. Several genes whose expression status was previously shown to be associated with CLL prognosis such as ZAP70, CRY1, LDOC1, SEPT10, LAG3, and LPL were differentially methylated in the promoter regions between M-CLL and U-CLL samples indicating that DNA methylation plays an important role in defining the gene expression patterns of these prognostic genes. We further validated 9 genes with IGHV-specific DMRs in the promoter regions using bisulfite pyrosequencing, and the results demonstrated excellent correlation between differential methylation and IGHV mutation status. These novel differentially methylated genes could be developed into biomarkers for CLL prognosis. In addition, DNA hypomethylation was observed in a significant number of genes involved in lymphocyte activation such as PDCD1, NFAT1, and CD5. DNA hypomethylation was observed in the proximal promoter and far up-stream enhancer regions of CD5, an important cell surface marker that uniquely identifies CLL. Overall, the DNA methylation landscape in CLL patients indicates that CLL B cells possess an active B-cell phenotype; at the same time, U-CLL and M-CLL are faithfully committed to their lineage resembling either naïve or memory B-cells. In summary, this comprehensive DNA methylation analysis has identified a large number of novel epigenetic changes in CLL patients. The results from this study will further advance our understanding of the epigenetic contribution to molecular subtypes in CLL. Overall design: To perform a transcriptome analysis in CLL, we generated sequencing libraries from total RNA isolated from purified B-cells of CLL patients and healthy donnors. The RNA-seq libraries were sequenced using Illumina HiSeq2000 sequencer with a read length of 100bp. 11 CLL B-cell samples, 3 normal control samples including one each of normal CD19+ B cells were studied. We generated 20-30 million Illumina sequencing reads for each sample.
Hypomethylation coordinates antagonistically with hypermethylation in cancer development: a case study of leukemia.
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View SamplesBacillus anthracis is a gram-positive, aerobic, spore-forming, rod-shaped bacterium which has recently been used as an agent of bioterrorism. Because there is a significant delay between the initial contact of the spore with the host and clinical evidence of disease, there appears to be temporary containment of the pathogen by the innate immune system. Contact with the human alveolar macrophage (HAM) plays a key role in the innate immune response to B. anthracis spores. Therefore, the early macrophage response to anthrax exposure is important in understanding the pathogenesis of this disease. The majority of genes modulated by spores were upregulated, and a lesser number were downregulated. The data was subjected to Ingenuity Pathway analysis, the Database for Annotation, Visualization and Integrated Discovery (DAVID) analysis, and the Promoter Analysis and Interaction Network Toolset (PAINT). Among the upregulated genes, we identified a group of chemokine ligands, apoptosis genes and, interestingly, keratin filament genes. Central hubs regulating the activated genes were TNF-alpha, NF-B and their ligands/receptors. Other activated genes included IL-1alpha and IL-18. RNA for these, and several additional cytokines including IL-6, IL-1gamma, IP-10 and GM-CSF, were differentially expressed from 1.6- to 27-fold. The microarray cytokine data is consistent with our previously published findings which demonstrated that there was 4- to 43-fold induction of these cytokines at the transcriptional and translational levels as determined by RNase protection assays and ELISA. The PAINT analysis revealed that the majority of the genes affected by spores contain the binding site for c-Rel, a member of the NF-B family of transcription factors. Other transcription regulatory elements contained in many of the upregulated genes were c-Myb, CP2, Barbie Box, E2F and CRE-BP1. This study is the first detailed microarray analysis to describe the HAM response to B. anthracis.
Gene expression profiling of human alveolar macrophages infected by B. anthracis spores demonstrates TNF-alpha and NF-kappab are key components of the innate immune response to the pathogen.
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View SamplesSle1c is a sublocus of the NZM2410-derived Sle1 major susceptibility locus. We have previously shown that Sle1c contributes to lupus pathogenesis by conferring CD4+ T cell-intrinsic hyperactivation and increased susceptibility to chronic graft-versus-host disease (cGVHD) that mapped to the centromeric portion of the locus. In this study, we have refined the centromeric sublocus to a 675Kb interval, termed Sle1c2. Recombinant congenic strains expressing Sle1c2 exhibited a T cell-intrinsic CD4+ T cell hyperactivation and cGVHD susceptibility, similar to mice with the parental Sle1c.
Murine lupus susceptibility locus Sle1c2 mediates CD4+ T cell activation and maps to estrogen-related receptor γ.
Sex, Age, Specimen part
View SamplesMany reports show an association between the Pst system, the Pho regulon related genes and bacterial virulence. Our previous results showed that a functional Pst system is required for full virulence, resistance to serum, polymyxin B and acid shock. However, the interplay between the Pst system and virulence has an unknown molecular basis. To understand global APEC virulent strain responses to Pho regulon activation, we conducted transcriptome profiling experiments comparing the APEC chi7122 strain and its isogenic Pst mutant grown in rich phosphate medium using the Affymetrix GeneChip E. coli Genome 2.0 Array. The Affymetrix GeneChip E. coli Genome 2.0 Array contains the genome of the E. coli MG1655 and three pathogenic E. coli strain (EDL933, Sakai and CFT073) representing 20,366 genes. While comparing genes expression between Pst mutant and the wild type chi7122 strain, 471 genes are either up- (254) or down-regulated (217) of at least 1.5-fold, with a p-value inferior or equal to 0.05 and a false discovery rate of 2.71%.
Genome-wide transcriptional response of an avian pathogenic Escherichia coli (APEC) pst mutant.
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View SamplesAnalysis of Nestin-GFP+ pericytes flow sorted from 3-day-old mouse cutaneous adipose tissue, comparing controls with wild type PDGFRa, and mutants with increased PDGFRa signaling driven by a Cre/lox-inducible D842V knockin mutation in the PDGFRa kinase domain. The control cells have adipogenic properties in vitro or when transplanted subcutaneously into recipient mice. The D842V mutant cells show altered behavior in the same assays, with poor adipogenic differentiation but a propensity to transition into profibrotic cells that secrete collagen Overall design: 3 Nes-GFP+ cells samples; 3 Nes-GFP;Nes-Cre;PDGFRa+/[S]D842V samples
PDGFRα signaling drives adipose tissue fibrosis by targeting progenitor cell plasticity.
No sample metadata fields
View SamplesBACKGROUND. Human prostate cancer LNCaP and PC-3 cell lines have been extensively used as prostate cancer cell models to study prostate cancer progression and to develop therapeutic agents. Although LNCaP and PC-3 cells are generally assumed to represent early and late stages of prostate cancer development, respectively, there is limited information regarding comprehensive gene expression patterns between these two cells lines and relating these cells to prostate cancer progression based on their gene expression.
Unique patterns of molecular profiling between human prostate cancer LNCaP and PC-3 cells.
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View SamplesA major problem in cancer research is the lack of a tractable model for delayed metastasis. Herein we show that cancer cells suppressed by SISgel, a gel-forming normal ECM material derived from Small Intestine Submucosa (SIS), in flank xenografts show properties of suppression and re-activation that are very similar to normal delayed metastasis and suggest these suppressed cells can serve as a novel model for developing therapeutics to target micrometastases or suppressed cancer cells. Co-injection with SISgel suppressed the malignant phenotype of highly invasive J82 bladder cancer cells and highly metastatic JB-V bladder cancer cells in nude mouse flank xenografts. Cells could remain viable up to 120 days without forming tumors and appeared much more highly differentiated and less atypical than tumors from cells co-injected with Matrigel. In 40% of SISgel xenografts, growth resumed in the malignant phenotype after a period of suppression or dormancy for at least 30 days and was more likely with implantation of 3 million or more cells. Ordinary Type I collagen did not suppress malignant growth, and tumors developed about as well with collagen as with Matrigel. A clear signal in gene expression over different cell lines was not seen by transcriptome microarray analysis, but in contrast, Reverse Phase Protein Analysis of 250 proteins across 4 cell lines identified Integrin Linked Kinase (ILK) signaling that was functionally confirmed by an ILK inhibitor. We suggest that cancer cells suppressed on SISgel could serve as a model for dormancy and re-awakening to allow for the identification of therapeutic targets for treating micrometastases.
Suppression and activation of the malignant phenotype by extracellular matrix in xenograft models of bladder cancer: a model for tumor cell "dormancy".
Cell line
View SamplesThe respiratory system is a complex network of many cell types, including subsets of macrophages and dendritic cels, that work together to maintain steady-state respiration. Due to limitations in acquiring cells from healthy human lung, these subsets remain poorly characterized transcriptionally and phenotypically. We set out to systemically identify these subsets in human airways, by developing a schema of isolating large numbers of cells by whole lung bronchoalveolar lavage. Six subsets of phagocytic antigen presenting cells were consistently observed, which varied in their ability to internalize bacterial particles. Subsets could be further separated by their inherent capacities to upregulate CD83, CD86, and CCR7. Whole genome transcriptional profiling revealed a clade of true dendritic cells distinct from a macrophage/monocyte clade. Each clade, and each member of both clades, could be discerned by specific genes of increased expression, which would serve as markers for future studies in healthy and diseased states.
Transcriptional Classification and Functional Characterization of Human Airway Macrophage and Dendritic Cell Subsets.
Sex, Age
View SamplesTh1/Th17-type T-cell responses are upregulated in Behcets disease (BD). However, signaling pathways associated with this aberrant immune response are not clarified. Whole-genome microarray profiling was performed with human U133 (Plus 2.0) chips using mRNA of isolated CD14+ monocytes and CD4+ T-cells from PBMC in patients with BD (n=9) and healthy controls (HC) (n=9). Flow cytometric analysis of unstimulated (US) and stimulated (PHA) STAT3 and pSTAT3 expressions of PBMCs were also analysed (BD and HC, both n=26). JAK1 was observed to be upregulated in both CD14+ monocytes (1.94 fold) and CD4+ T-lymphocytes (1.40 fold) of BD patients. Using canonical pathway enrichment analysis, JAK/STAT signaling was identified as activated in both CD14+ monocytes (p=2.95E-06) and in CD4+ lymphocytes (p=8.13E-04) in BD. Interferon (p=1.02E-07) and IL-6 (p=8.91E-03) signaling pathways were also prominent in CD14+ monocytes. Basal unstimulated total STAT3 expression was significantly higher in BD (1.2 vs 3.45, p<0.05). The JAK1/STAT3 signaling pathway is activated in BD, possibly through the activation of Th1/Th17-type cytokines such as IL-2, IFN, IL-6, IL-17 and IL-23.
Activation of the JAK/STAT pathway in Behcet's disease.
Specimen part, Disease
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