Young adult fer-15;fem-1 Caenorhabditis elegans were infected with Staphylococcus aureus for 8 h to determine the transcriptional host response to Staphylococcus aureus. Analysis of differential gene expression in C. elegans young adults exposed to two different bacteria: E. coli strain OP50 (control), wild-type Staphylococcus aureus RN6390. Samples were analyzed at 8 hours after exposure to the different bacteria. These studies identified C. elegans genes induced by pathogen infection.
Distinct pathogenesis and host responses during infection of C. elegans by P. aeruginosa and S. aureus.
Disease, Disease stage
View SamplesThe nematode Caenorhabditis elegans offers currently untapped potential for carrying out high-throughput, live-animal screens of low molecular weight compound libraries to identify molecules that target a variety of cellular processes. We previously used a bacterial infection assay in C. elegans to identify 119 compounds that affect host-microbe interactions among 37,214 tested. We subsequently found that one of these small molecules, RPW-24, protects C. elegans from bacterial infection by stimulating the host immune response of the nematode. Using transcriptome profiling, epistasis pathway analyses with C. elegans mutants, and an RNAi screen, we showed that RPW-24 promotes resistance to Pseudomonas aeruginosa infection by inducing the transcription of a remarkably small number of C. elegans genes (~1.3% of all genes) in a manner that partially depends on the evolutionarily-conserved p38 MAP kinase pathway and the transcription factor ATF-7. These data demonstrated that the immunostimulatory activity of RPW-24 is required for its efficacy and define a novel C. elegans-based strategy to identify compounds with activity against antibiotic-resistant bacterial pathogens. Here we present the microarray data that were used to define the genes that are differentially regulated in wild-type nematodes following exposure to RPW-24.
Stimulation of host immune defenses by a small molecule protects C. elegans from bacterial infection.
Specimen part, Treatment
View SamplesMany pathogens secrete toxins that target key host processes resulting in the activation of immune pathways. The secreted Pseudomonas aeruginosa toxin Exotoxin A (ToxA) disrupts intestinal protein synthesis which triggers the induction of a subset of P. aeruginosa-response genes in the nematode Caenorhabditis elegans. We found that losing one ToxA-induced C. elegans gene, the Tribbles pseudokinase ortholog nipi-3, results in hypersusceptibility to both P. aeruginosa and ToxA. We determined that NIPI-3 mediates the post-developmental expression of intestinal immune genes and proteins and primarily functions in parallel to known immune pathways, including p38 PMK-1 MAPK signaling. Here we present the microarray data that was used to determine that (1) nipi-3 regulates immune gene expression and that (2) nipi-3 and pmk-1 regulate non-overlapping gene sets consistent with them functioning in parallel.
Tribbles ortholog NIPI-3 and bZIP transcription factor CEBP-1 regulate a Caenorhabditis elegans intestinal immune surveillance pathway.
Specimen part
View SamplesAcute Myeloid Leukemia AML is a cancer in which the process of normal cell hematopoietic differentiation is disrupted. Evidence exists that AML comprises a hierarchy with leukemic stem cells giving rise to more differentiated, but immature and functionally incompetent populations. The similarity of these AML subpopulations to normal stages of hematopoietic differentiation has not been dissected comprehensively at the transcriptional level. Here we introduce Normal Memory Analysis (NorMA), a data analysis method that extracts from omic data the remnants of the healthy normal-like phenotype. Applying NorMA to gene expression data from AML uncovered a wealth of information in the normal-like component of data: the normal hematopoietic memory of AML tumor cells. We found significant variation within the patient population, and we found strong association of this normal hematopoietic memory with survival. We found that undifferentiated NorMA phenotype has significantly worse survival than differentiated NorMA phenotype, showing that the NorMA classification of tumors captures a biologically meaningful stratification of patients, with highly significant survival association. Patients with NorMA phenotype in the undifferentiated Hematopoietic Stem Cell HSC stage had the worst survival, with median survival time under 6 months. We further found significant survival differences between tumor groups with differentiated NorMA phenotype, depending on their hematopoietic path: AML patients with NorMA phenotype in megakaryocyte-erythroid progenitor MEP stage had significantly better survival than those with NorMA phenotype in granulocyte-macrophage progenitor GMP stage. Thus NorMA produced a stratification of AML cohorts by differentiation stage, with significant outcome differences. It also provided clean molecular signatures for these stages. NorMA can be used in many other contexts, to explore for example the tumor cell of origin, or disease predisposition.
An LSC epigenetic signature is largely mutation independent and implicates the HOXA cluster in AML pathogenesis.
Specimen part
View SamplesIn response to the cytokines, macrophage colony-stimulating factor and receptor activator of NF-kB ligand, monocyte precursors differentiate into bone marrow-derived macrophages (BMDMs) that ultimately fuse to form multi-nucleated osteoclasts, following a tightly controlled genetic program where specific sets of genes are differentially expressed.
Osteoclast-mediated bone resorption is controlled by a compensatory network of secreted and membrane-tethered metalloproteinases.
Age, Specimen part, Time
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Large-scale hypomethylated blocks associated with Epstein-Barr virus-induced B-cell immortalization.
Specimen part, Time
View SamplesTo determine what DNA methylation and gene expression changes occur following EBV transformation. B-cells were isolated from 3 donors. Resting, CD40 activated and EBV transfromed cells from each donor was analyzed. Each sample was assayed using Affymetrix expression arrays and whole genome bisulfite sequenicng. Additional time points during transformation and activation were sequenced as well, but not assayed for expression.
Large-scale hypomethylated blocks associated with Epstein-Barr virus-induced B-cell immortalization.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Age and sun exposure-related widespread genomic blocks of hypomethylation in nonmalignant skin.
Sex, Age, Specimen part
View SamplesGene expression profiling of epidermal samples obtained from sun-exposed and sun-protected body sites from younger (<35 years old) and older (>60 years old) individuals. The Affymetrix U133A plus 2.0 array was used to obtain gene expression data. Samples included 4 younger sun exposed epidermal samples, 4 older sun exposed epidermal samples, 3 younger sun protected epidermal samples, 5 older sun protected epidermal samples.
Age and sun exposure-related widespread genomic blocks of hypomethylation in nonmalignant skin.
Sex, Age, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Donor cell type can influence the epigenome and differentiation potential of human induced pluripotent stem cells.
Specimen part
View Samples