Gene expression profiles of M. tuberculosis constitutively expressing the transcriptional regulator DosR (Rv3133c).
ABSTRACT: Background: Conflicting results have been reported about the role of the two-component sensor and transcriptional regulator DosS/DosR, controlling the expression of the dormancy DosR regulon, for in vivo virulence of M. tuberculosis. Here, we have used a new approach to further analyze the relevance of the dosRS system, by driving DosR (Rv3133c) expression under the control of a constitutive promoter (phsp60). Methodology/Principal Findings: M. tuberculosis H37Rv constitutively expressing the transcriptional regulator DosR (Mtb::DosR) was compared to wild type M. tuberculosis (Mtb+/+) for in vitro growth kinetics and expression of the target genes of the DosR dormancy regulon, for in vivo virulence and for immunogenicity in mice. Under aerobic conditions, hsp60-driven DosR induced the expression of 28 out of 39 tested DosR regulon genes. In vitro growth characteristics were comparable for both strains, but Mtb::DosR showed an attenuated in vivo phenotype in immunocompetent mice, as indicated by reduced bacterial replication, reduced pulmonary immunopathology, reduced cachexia and significantly prolonged survival time as compared Mtb+/+. In immunodeficient SCID mice, Mtb::DosR was fully virulent. RT-qPCR analysis revealed a strong and comparable pulmonary TNF-?? and IL-23 expression following intratracheal infection, whereas IL-12 and IL-17 expression was slightly higher with wild type Mtb+/+. Finally, mice persistently infected with Mtb::DosR for 8 months showed five to tenfold higher lung IFN-?? responses against ten of the 48 DosR regulon encoded antigens (Rv1733c, Rv1734, Rv1738, Rv1996, Rv1997, Rv2029c, Rv2623, Rv2627c, Rv2628 and Rv3127) than mice actively infected with Mtb+/+. In spleen however, DosR regulon encoded antigen specific IFN-?? responses were similar in both groups. Conclusions/Significance. Collectively, these results suggest that increased DosR regulon encoded antigen specific pulmonary T cell responses are responsible for the attenuated phenotype of Mtb::DosR and that infection with Mtb::DosR could be used as a new animal model for studying key aspects of latent tuberculosis. Set of arrays that are part of repeated experiments
Project description:In this report we demonstrated that under aerobic conditions, Mycobacterium bovis BCG expressing an hsp60-driven second copy of the hypoxia-related transcriptional regulator DosR increased 2-fold or greater the expression of 38 out of the 48 genes belonging to the DosR regulon, including the latency antigens Rv1733c, Rv2029, Rv2627, and Rv2628. Expression of DosR under these conditions slightly delayed in vitro growth, but did not promote a non-replicating state as opposed to microaerobic and hypoxic adaptation. Our results suggest BCG producing DosR can be cultured under standard in vitro conditions, allowing evaluation of this strain as a latency-specific vaccine candidate. Set of arrays that are part of repeated experiments
Project description:ABSTRACT Background. Acute Kawasaki disease (KD) is difficult to distinguish from other acute rash/fever illnesses, in part because the etiologic agent(s) and pathophysiology remain poorly characterized. As a result, diagnosis and critical therapies may be delayed. Methods. We used DNA microarrays to identify possible diagnostic features of KD. We compared gene expression patterns in the blood of 23 children with acute KD and 18 age-matched febrile children with three illnesses that resemble KD. Results. Genes associated with platelet and neutrophil activation were expressed at higher levels in KD patients than in patients with acute adenovirus infections or systemic adverse drug reactions but not in patients with scarlet fever; genes associated with B cell activation were also expressed at higher levels in KD patients than in controls. A striking absence of interferon-stimulated gene expression in the KD patients was confirmed in an independent cohort of KD subjects. We successfully predicted the diagnosis in 21 of 23 KD patients and 7 of 8 adenovirus patients using a set of 38 gene transcripts. Conclusions. These findings provide insight into the molecular features that distinguish KD from other febrile illnesses, and support the feasibility of developing novel diagnostic reagents for KD based on the host response. A disease state experiment design type is where the state of some disease such as infection, pathology, syndrome, etc is studied. Disease State: One of Kawasaki Disease (KD) or control (C) of Scarlet fever (C-sf), adenovirus infection (C-ai) or drug reaction (C-dr) disease_state_design
Project description:Pancreatobiliary cancers have among the highest mortality rates of any cancer type. Discovering the full spectrum of molecular genetic alterations may suggest new avenues for therapy. To catalogue genomic alterations, we carried out array-based genomic profiling of 31 exocrine pancreatic cancers and 6 distal bile duct cancers, expanded as xenografts to enrich the tumor cell fraction. We identified numerous focal DNA amplifications and deletions, including in 19% of pancreatobiliary cases gain at cytoband 18q11.2, a locus uncommonly amplified in other tumor types. The smallest shared amplification at 18q11.2 included GATA6, a transcriptional regulator previously linked to normal pancreas development. When amplified, GATA6 was overexpressed at both the mRNA and protein level, and strong immunostaining was observed in 25 of 54 (46%) primary pancreatic cancers compared to 0 of 33 normal pancreas specimens surveyed. GATA6 expression in xenografts was associated with specific microarray gene-expression patterns, enriched for GATA binding sites and mitochondrial oxidative phosphorylation activity. siRNA mediated knockdown of GATA6 in pancreatic cancer cell lines with amplification led to reduced cell proliferation, cell cycle progression, and colony formation. Our findings indicate that GATA6 amplification and overexpression contribute to the oncogenic phenotypes of pancreatic cancer cells, and implicate GATA6 as a lineage-specific oncogene in pancreatobiliary cancer, with implications for novel treatment strategies. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Tissue type: cancer xenograft from diff tissues Keywords: Logical Set cDNA microarrays from the Stanford Functional Genomics Facility were used to perform gene expression profiling on 28 out of 31 of the exocrine pancreatic cancer and all 6 distal bile duct cancer xenografts. Using regression correlation
Project description:This SuperSeries is composed of the following subset Series: GSE13914: Molecular profiling of breast cancer cell lines defines relevant tumor models (aCGH) GSE15361: Molecular profiling of breast cancer cell lines defines relevant tumor models (gene expression) Refer to individual Series
Project description:This SuperSeries is composed of the following subset Series: GSE12166: TJ411(fer-15(b26)II; age-1(hx542)II) vs. BA713(fer-15(b26)II) GSE12167: TJ1081)fer-15(b26)II; daf-16(m26)I) vs. BA713(fer-15(b26)II) GSE12168: Aging Time course Refer to individual Series
Project description:This SuperSeries is composed of the following subset Series: GSE13206: Human shSIRT6 TNF-alpha timecourse GSE13207: Mouse Sirt6-/- TNF-alpha timecourse GSE13208: Mouse Sirt6-/- tissues GSE13209: Mouse Sirt6-/- RelA+/- tissues Refer to individual Series
Project description:Treatment of PBMC with 0.6 pM cytokine from 0-24h Abstract: Background Interferons are key modulators of the immune system, and are central to the control of many diseases. The response of immune cells to stimuli in complex populations is the product of direct and indirect effects, homotypic and heterotypic cell interactions. Dissecting the global transcriptional profiles of immune cell populations may provide insights into this regulatory interplay. The host transcriptional response may also be useful in discriminating between disease states, and in understanding pathophysiology. The transcriptional programs of cell populations in health therefore provide a paradigm for deconvoluting disease-associated gene expression profiles. Results: We used human cDNA microarrays to (1) compare the gene expression programs in human peripheral blood mononuclear cells (PBMCs) elicited by 6 major mediators of the immune response: interferons a, b, w and g, IL12 and TNFa; and (2) characterise the transcriptional responses of purified immune cell populations (CD4+ and CD8+ T cells, B cells, NK cells and monocytes) to IFNg stimulation. We defined a highly stereotyped response to type I interferons, while responses to IFNg and IL12 were largely restricted to a subset of type I interferon-inducible genes. TNFa stimulation resulted in a distinct pattern of gene expression. Cell type-specific transcriptional programs were identified, highlighting the pronounced response of monocytes to IFNg, and emergent properties associated with IFN-mediated activation of mixed cell populations. Conclusions: This information provides a detailed view of cellular activation by immune mediators, and contributes an interpretive framework for the detection and definition of host immune responses in a variety of disease settings. PBMC extraction and stimulation Human primary peripheral blood mononuclear cells (PBMCs) were purified from whole blood of healthy donors using Ficoll-Paque PLUS (GE Healthcare) according to manufacturers instructions. PBMCs were incubated at 1.5-2.0 x 106 cells/well for 24 h before stimulation in RPMI 1640 medium supplemented with 10% heat-inactivated foetal calf serum and 2 mM L-glutamine (Invitrogen) at 37C, 5% CO2. Cells were treated with 0.006 pM, 0.6 pM or 60 pM recombinant IFNg (R&D Systems), and sampled at time intervals from 0.5 h to 12 h after stimulation. Additionally, cells were treated with 0.1 % BSA/PBS alone and used for untreated (mock) control time courses. RNA extraction and amplification Total RNA was extracted in TRIzol LS (Invitrogen) followed by standard chloroform purification and isopropanol precipitation. RNA was resuspended in RNase-free water, quantitated on the NanoDrop ND-1000 spectrophotometer (NanoDrop Technologies) and stored at -80C. 500 ng total RNA was amplified using the MessageAmp modified Eberwine linear amplification procedure (Applied Biosystems). All samples to be compared were extracted and amplified together. Microarray analysis 4 ug amplified RNA was labelled with Cy5-dUTP (GE Healthcare) and combined with 3 ug of Cy3-labelled reference cDNA derived from a pool of RNA derived from a panel of 11 human cell lines (Stratagene Universal Human Reference RNA). The samples were washed and concentrated using MinElute columns (Qiagen) and competitively hybridised to custom printed cDNA microarrays containing 37,632 elements for approximately 18,000 unique human genes. The hybridised slides were scanned using a GenePix 4000A microarray scanner (Axon Instruments). Comparative spot intensities were calculated from the images, and areas of poor quality excluded from further analysis using GenePix Pro 6.0 (Axon Instruments). Data were deposited in the Stanford Microarray Database. Analysis was restricted to cDNA elements with a regression correlation of > 0.6, fluorescence intensities of > 2.5 fold signal/background in Cy3 or Cy5 channels and a minimum signal intensity of > 100 in both channels for at least 80% of the arrays. The expression ratios were normalised for array variation, and the data zero-transformed using a custom-designed Microsoft Excel macro (C. Liu, Stanford). The statistical package SAM (Significance Analysis of Microarrays, version 1.15) was used to identify genes significantly differentially expressed in the normalised data sets by pairwise comparison with a minimum 2 fold cutoff at a false discovery rate of < 1% of the median. The transformed datasets were then hierarchically clustered using Cluster 2.11 and the results displayed using Treeview 1.60. A compound treatment design type is where the response to administration of a compound or chemical (including biological compounds such as hormones) is assayed.
Project description:These 12 arrays are the basis for Figure 1 of the "An interferon-response induced by tumor-stroma interaction in a subset of human breast cancers" manuscript. Figure 1: Effect of heterotypic interaction between breast cancer cell line MDA-MB231 and CCL-171 fibroblast. Biologically independent replicates of the mono-cultured fibroblast CCL-171, the breast cancer cell line MDA-MB231 and the mixed co-culture of CCL-171 and MDA-MB231 were grown for 48h at low serum conditions and characterized by DNA microarray hybridization. Hierarchical clustering of a total of 4333 elements that display a greater than 3-fold variance in expression in more than 3 different experimental samples. Data from individual elements or genes are represented as single rows, and different experiments are shown as columns. Red and green denote expression levels of the samples. The intensity of the color reflects the magnitude of the deviation from baseline. Unsupervised hierarchical clustering of the experiments grouped the biological replicates together. Gene expression varied considerably between fibroblast and MDA-MB231 as expected for cells of mesenchymal or epithelial origin respectively. The co-culture profile showed mainly intermediate expression levels. However, the vertical black bar marks a cluster of genes induced in all co-cultures compared to both mono-cultures indicating that they are induced by heterotypic interaction Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Computed
Project description:Primary skin fibroblasts from four Niemann-Pick type C patients homozygous for the I1061T mutation and four control individuals were cultured under identical conditions in DMEM containing 10% fetal bovine serum. Cells were harvested at 50-70% confluency. mRNA was isolated with the FastTrack 2.0 mRNA isolation kit according to the manufacturer's instructions (Invitrogen, Carlsbad, CA). A reference RNA comprised of 10 cell lines was used as the control for each hybridized sample (Stratagene, La Jolla, CA). Both sample and reference RNAs were amplified using the MessageAmp II aRNA amplification kit (Ambion, Austin, TX). Set of arrays that are part of repeated experiments Biological Replicate Complex
Project description:5 arrays per condition (covering 3 biological replicate experiments) were performed on Human Foreskin Fibroblasts (HFFs) at 44 hours post infection. The four experimental conditions include uninfected "standard", uninfected "stress", tachyzoite-infected "standard+TZ", and bradyzoite-infected "stress+BZ". Bradyzoite conversion is induced at 4 hours post infection with replacement of standard DMEM+10% FCS with RPMI+1%FCS buffered with 50mM Hepes to pH 8.15. Approximately 20% of cells are infected and bradyzoite conversion is >90% in these experiments. These data are normalized using 2-D loess (span factor .4). The calculations in the manuscript are based on are log2 ratios of normalized channel 2/channel 1 medians. A development or differentiation experiment design type assays events associated with development or differentiation or moving through a life cycle. Development applies to organism(s) acquiring a mature state, and differentiation applies to cells acquiring specialized functions. Developmental Stage: Uninfected (standard or stress medium), or Tachyzoite-infected (standard medium) or Bradyzoite-infected (stress medium) Complex