Salmonella enterica is a Gram-negative bacterium that causes gastroenteritis, bacteremia and typhoid fever in several animal species including humans. Its virulence is greatly dependent on two type III secretion systems (T3SSs), encoded in pathogenicity islands 1 (SPI1) and 2 (SPI2), respectively. These systems translocate proteins called effectors into eukaryotic host cell. Effectors interfere with certain host signal transduction pathways to allow the internalization of pathogens and their survival and proliferation inside vacuoles. SteA is one of the few Salmonella effectors that are substrates of both T3SSs. Nothing is known about the function of this protein inside the host cells. Here, we used gene arrays and bioinformatics analysis to study the genetic response of human epithelial cells to SteA. We found that constitutive synthesis of SteA in epithelial cells leads to induction of genes related to extracellular matrix organization and regulation of cell proliferation and serine/threonine kinase signaling pathways. SteA also represses genes related to immune processes and regulation of purine nucleotide synthesis and pathway-restricted SMAD protein phosphorylation. Consisted with this analysis a cell biology approach revealed that epithelial cells expressing steA show altered cell morphology, reduction of cytotoxicity, cell-cell adhesion and migration capability, and increase in endocytosis.
Global impact of Salmonella type III secretion effector SteA on host cells.
Cell line
View SamplesUntreated HIV-1 infection progresses through acute and asymptomatic stages to AIDS. While each of the three stages has well-known clinical, virologic and immunological characteristics, much less is known of the molecular mechanisms underlying each stage. Here we report lymphatic tissue microarray analyses revealing for the first time stage-specific patterns of gene expression during HIV-1 infection. We show that while there is a common set of key genes with altered expression throughout all stages, each stage has a unique gene-expression signature. The acute stage is most notably characterized by increased expression of hundreds of genes involved in immune activation, innate immune defenses (e.g.MDA-5, TLR-7 and -8, PKR, APOBEC3B, 3F, 3G), adaptive immunity, and in the pro-apoptotic Fas-Fas-L pathway. Yet, quite strikingly, the expression of nearly all acute-stage genes return to baseline levels in the asymptomatic stage, accompanying partial control of infection. In the AIDS stage, decreased expression of numerous genes involved in T cell signaling identifies genes contributing to T cell dysfunction. These common and stage-specific, gene-expression signatures provide new insights into the molecular mechanisms underlying the host response and the slow, natural course of HIV-1 infection.
Microarray analysis of lymphatic tissue reveals stage-specific, gene expression signatures in HIV-1 infection.
Sex, Age, Specimen part, Disease, Disease stage, Race, Subject
View SamplesThis project is based on the hygiene hypothesis that exposure to TB provides a protective mechanism against asthma through specific cytokines and the balance of Th1, Th2 cells. Additionally, expression changes are examined in patients with and without atopy in combination with asthma and PPD status. Expression levels were evaluated in CD4+ cells isolated from peripheral blood of 30 patients. Each patient was evaluated on the entire U133 Affymetrix GeneChip set.
A module-based analytical strategy to identify novel disease-associated genes shows an inhibitory role for interleukin 7 Receptor in allergic inflammation.
No sample metadata fields
View SamplesThymic lymphomas develop spontaneously in LN3 mice. As for T-ALL in general, ex vivo LN3 lymphoma cells require stromal support to remain viable in culture. We found that primary stromal cells from thymic lymphomas, but not from wild-type thymi, support ex vivo lymphoma survival. By FACS sorting stromal populations, we identified dendritic cells in the tumor microenvironment as the cells capable of supporting lymphoma survival.
Endogenous dendritic cells from the tumor microenvironment support T-ALL growth via IGF1R activation.
Sex, Age, Specimen part, Disease, Disease stage
View SamplesTumor cells exhibit aberrant metabolism characterized by high glycolysis even in the presence of oxygen. This metabolic reprogramming, known as the Warburg effect, provides tumor cells with the substrates and redox potential required for the generation of biomass. Here, we show that the mitochondrial NAD-dependent deacetylase SIRT3 is a crucial regulator of the Warburg effect. SIRT3 loss promotes a metabolic profile consistent with high glycolysis required for anabolic processes in vivo and in vitro. Mechanistically, SIRT3 mediates metabolic reprogramming independently of mitochondrial oxidative metabolism and through HIF1a, a transcription factor that controls expression of key glycolytic enzymes. SIRT3 loss increases reactive oxygen species production, resulting in enhanced HIF1a stabilization. Strikingly, SIRT3 is deleted in 40% of human breast cancers, and its loss correlates with the upregulation of HIF1a target genes. Finally, we find that SIRT3 overexpression directly represses the Warburg effect in breast cancer cells. In sum, we identify SIRT3 as a regulator of HIF1a and a suppressor of the Warburg effect.
SIRT3 opposes reprogramming of cancer cell metabolism through HIF1α destabilization.
Specimen part
View Samples10 day old seedlings were treated with 5uM of the cytokinin Benzyladenine(BA)or DMSO at 15min, 45min, 120min, 480min and 1440min
Expression profiling of cytokinin action in Arabidopsis.
Age, Compound, Time
View SamplesBackground: A subset of infants are hyper-susceptible to severe/acute viral bronchiolitis (AVB), for reasons unknown. Purpose: To characterise the cellular/molecular mechanisms underlying infant AVB in circulating cells/local airways tissues. Methods: PBMC and nasal mucosal scrapings (NMS) were obtained from Infants (<18mths) and children (1.5-5yrs) during AVB and post-convalescence. Immune response patterns were profiled by multiplex analysis of plasma cytokines, flow cytometry, and transcriptomics (RNA-Seq). Molecular profiling of group-level data utilised a combination of upstream regulator and coexpression network analysis, followed by individual subject-level data analysis employing personalised N-of-1-pathways methodology. Results: Group-level analyses demonstrated that infant PBMC responses were dominated by monocyte-associated hyper-upregulated type I interferon signalling/pro-inflammatory pathways (drivers: TNF, IL6, TREM1, IL1B), versus a combination of inflammation (PTGER2, IL6) plus growth/repair/remodelling pathways (ERBB2, TGFB1, AREG, HGF) coupled with Th2 and NK-cell signalling in children. Age-related differences were not attributable to differential steroid usage or variations in underlying viral pathogens. Nasal mucosal responses were comparable qualitatively in infants/children, dominated by interferon types I-III, but the magnitude of upregulation was higher in infants (range 6-48-fold) than children (5-17-fold). N-of-1-pathways analysis confirmed differential upregulation of innate immunity in infants and NK cell networks in children, and additionally demonstrated covert AVB response sub-phenotypes that were independent of chronological age. Conclusions: Dysregulated expression of interferon-dependent pathways following respiratory viral infections is a defining immunophenotypic feature of AVB-susceptible infants and a subset of children. Susceptible subjects appear to represent a discrete subgroup who cluster based on (slow) kinetics of postnatal maturation of innate immune competence. Overall design: The study design consisted of PBMC from infants (<18months, n=15 pairs) and pre-school children (2-5yrs, n=16 pairs) sampled during severe acute viral bronchiolitis (acute visit = AV) and following recovery during convalescence (convalescent visit = CV). RNA-Seq profiles were generated by sequencing llumina HiSeq2500, 50bp single-end reads, v4 chemistry. Samples were sequenced across two lanes and collapsed prior analysis.
Personalized Transcriptomics Reveals Heterogeneous Immunophenotypes in Children with Viral Bronchiolitis.
Subject
View SamplesBackground: A subset of infants are hyper-susceptible to severe/acute viral bronchiolitis (AVB), for reasons unknown. Purpose: To characterise the cellular/molecular mechanisms underlying infant AVB in circulating cells/local airways tissues. Methods: PBMC and nasal mucosal scrapings (NMS) were obtained from Infants (<18mths) and children (1.5-5yrs) during AVB and post-convalescence. Immune response patterns were profiled by multiplex analysis of plasma cytokines, flow cytometry, and transcriptomics (RNA-Seq). Molecular profiling of group-level data utilised a combination of upstream regulator and coexpression network analysis, followed by individual subject-level data analysis employing personalised N-of-1-pathways methodology. Results: Group-level analyses demonstrated that infant PBMC responses were dominated by monocyte-associated hyper-upregulated type I interferon signalling/pro-inflammatory pathways (drivers: TNF, IL6, TREM1, IL1B), versus a combination of inflammation (PTGER2, IL6) plus growth/repair/remodelling pathways (ERBB2, TGFB1, AREG, HGF) coupled with Th2 and NK-cell signalling in children. Age-related differences were not attributable to differential steroid usage or variations in underlying viral pathogens. Nasal mucosal responses were comparable qualitatively in infants/children, dominated by interferon types I-III, but the magnitude of upregulation was higher in infants (range 6-48-fold) than children (5-17-fold). N-of-1-pathways analysis confirmed differential upregulation of innate immunity in infants and NK cell networks in children, and additionally demonstrated covert AVB response sub-phenotypes that were independent of chronological age. Conclusions: Dysregulated expression of interferon-dependent pathways following respiratory viral infections is a defining immunophenotypic feature of AVB-susceptible infants and a subset of children. Susceptible subjects appear to represent a discrete subgroup who cluster based on (slow) kinetics of postnatal maturation of innate immune competence. Overall design: The study design consisted of PBMC from infants (<18months, n=15 pairs) and pre-school children (2-5yrs, n=16 pairs) sampled during severe acute viral bronchiolitis (acute visit = AV) and following recovery during convalescence (convalescent visit = CV). RNA-Seq profiles were generated by sequencing llumina HiSeq2500, 50bp single-end reads, v4 chemistry. Samples were sequenced across two lanes and collapsed prior analysis.
Personalized Transcriptomics Reveals Heterogeneous Immunophenotypes in Children with Viral Bronchiolitis.
Subject
View SamplesSystemic vaccination with the attenuated virus SIVmac239-Nef provides sterilizing or partial protection to rhesus monkeys challenged with WT SIV strains, providing important opportunities to study key immunological components of a protective host response. Here we show that intravenous vaccination with SIVmac239-Nef provides two potentially crucial immunological barriers localized at mucosal surfaces that correlate with the vaccines protective effects against WT SIVmac251 vaginal challenge: 1) a conditioned and coordinated response from the mucosal epithelium that blunts the early inflammatory and chemotactic signalling cascade that aids virus propagation and expansion; 2) early on-site generation/diversification of SIV-specific Abs from ectopic germinal center-like lymphoid aggregates. This unique host response to WT SIVmac251 in the female reproductive tract of SIVmac239-Nef-vaccinated animals points to a multi-layered strategy for a protective host response during immunodeficiency virus exposurerapid induction of humroal immunity at mucosal surfaces without the deleterious inflammatory side effects tied to innate recognition of virus. This vaccine-induced host response highlights potential key protective mechanisms needed for an effective HIV vaccine
Live simian immunodeficiency virus vaccine correlate of protection: immune complex-inhibitory Fc receptor interactions that reduce target cell availability.
Sex, Specimen part
View SamplesSide populations have recently been identified in ovarian cancers and may play an important role in post treatment relapse and resistance to chemotherapeutic drugs. In this study, we aimed to identify the differential expression between IGROV1 SP and NSP on Affymetrix HG-U133plus2 microarrays. We found ovarian tumour SP cells frequently over-express the multi-drug resistance associated P-glycoprotein (ABCB1) by Rank Product (FDR<0.05), and by geneset enrichment analysis, embryonic stem cell-associated NOS signature (Notch/Oct4/Sox2 regulated genes) and Polycomb Repressive Complex 2 (PRC2) genes were over-expressed, while PRC2-repressed target genes were significantly under-expressed in the SP from ovarian cell lines compared to non-SP (FDR<10-4).
Ovarian cancer stem cell-like side populations are enriched following chemotherapy and overexpress EZH2.
Specimen part
View Samples