Effective immune responses depend upon appropriate T cell differentiation in accord with the nature of an infectious agent, and the contingency of differentiation depends minimally on T cell antigen receptor, co-receptor, and cytokine signals. In this reverse genetic study we show that the Map Kinase, Erk2, is nonessential for T cell proliferation in the presence of optimum co-stimulation. Instead, it has opposite polar effects on T-bet and Gata3 expression and hence on Th1 and Th2 differentiation. Alternatively, in the presence of TGFbeta, the Erk pathway suppresses a large program of gene expression effectively limiting the differentiation of Foxp3+ T reg cells. In the latter case, the mechanisms involved include suppression of Gata3 and Foxp3, induction of Tbx21, phosphorylation of Smad2,3, and possibly suppression of Socs2, a positive inducer of Stat5 signaling. Consequently, loss of Erk2 severely impeded Th1 differentiation while enhancing the development of Foxp3+ induced T regulatory cells. Selected profiles of gene expression under multiple conditions of T cell activation illustrate the opposing consequences of Erk pathway signaling.
Polar opposites: Erk direction of CD4 T cell subsets.
Specimen part, Time
View SamplesCharacterization of the gene expression profiles of specific cell populations of the human urinary bladder provides an important set of research tools for the study of cellular differentiation and the cancer process. The transcriptome is a definitive identifier of each individual cell types. Surgically resected tissue was digested by collagenase and the different cell types were sorted by antibodies to cluster designation (CD) cell surface antigens. The sorted cells were analyzed by DNA microarrays. The transcriptome datasets were analyzed for differentially expressed genes and plotted on a principal components analysis space for cell lineage relationship. The following bladder cell types were analyzed: CD9+ urothelial, CD104+ basal, CD13+ stromal of lamina propria, CD9+ urothelial carcinoma cancer, and CD13+ urothelial carcinoma-associated stromal. Gene expression differences between the cell types of tumor and their respective non-cancer counterpart provide biomarker candidates. Basal cells of the bladder and prostate, although sharing CD cell surface markers, are quite different in overall gene expression. Furthermore, these cells lack transcript features of stem cell signature of embryonic stem or embryonal carcinoma cells. Cell type-specific transcriptomes are more informative than bulk tissue transcriptomes. The relatedness of different cell types can be determined by transcriptome dataset comparison.
Bladder expression of CD cell surface antigens and cell-type-specific transcriptomes.
Specimen part
View SamplesRetinoic acid (RA), the main active vitamin A metabolite, controls multiple biological processes such as cell proliferation and differentiation through genomic programs and kinase cascades activation. Several breast cancer cells respond to the antiproliferative effects of RA, but others are RA-resistant. In several cases resistance has been correlated to the amplification of the erb-b2 receptor tyrosine kinase 2 (ERBB2) gene, but the overall signaling and transcriptional pathways that are altered in such cells have not been elucidated. Here we compared two human breast cancer cell lines, the MCF7 cell line, which responds to the antiproliferative action of RA and the BT474 cell line, which is RA-resistant subsequent to ERBB2 amplification in a large-scale analysis of the phosphoproteins and in a genome-wide analysis of the RA-regulated genes. Using high-resolution nano-LC-LTQ-Orbitrap mass spectrometry associated to phosphopeptide enrichment, we found that several proteins involved in signaling and in transcription, are differentially phosphorylated after RA addition. The paradigm of these proteins is the RA receptor a (RARa), which was phosphorylated in MCF7 cells but not in BT474 cells. The panel of the RA-regulated genes was also different. Overall our results indicate that ERBB2 amplification interferes with the ability of RA to activate kinases with consequences on the phosphorylation of several proteins involved in transcription and thus on gene expression. Overall design: Two human breast cancer cell lines were compared for their repertoire of genes regulated by retinoic acid (RA): the RA sensitive MCF7 cell line and the RA resistant B7474 cell line
Phosphoproteome and Transcriptome of RA-Responsive and RA-Resistant Breast Cancer Cell Lines.
Specimen part, Cell line, Treatment, Subject
View SamplesThere is a growing need for fast and accurate methods for testing developmental neurotoxicity across industrial, pharmaceutical, and environmental chemical exposures. Current approaches, such as in vivo animal studies, and assays of animal and human primary cell cultures, suffer from challenges related to time, cost, and applicability to human physiology. Prior research demonstrated success employing machine learning to predict developmental neurotoxicity using gene expression data collected from complex human 3D tissue models exposed to various compounds, but the complexity of 3D tissue models require extensive expertise and effort to employ. While a 3D tissue model is more physiologically accurate, by focusing only on the goal of constructing an assay of developmental neurotoxicity, we propose that a simpler 2D tissue model may prove sufficient. We thus compared the accuracy of predictive models trained on data from a 2D tissue model with those trained on prior dataset from a more complex 3D tissue model, and found the accuracy of the 2D model to be substantially better than the 3D model. Furthermore, we found that the 2D tissue model is more robust and consistent under stringent gene set selection, whereas the 3D tissue model suffers substantial degradation of accuracy. While both approaches have advantages and disadvantages, we propose that our described 2D tissue model has the potential to serve as a valuable tool for decision makers when prioritizing neurotoxicity screening. Overall design: H1-NPC cells were thawed and expanded in DF3S+N2B27+5ng/ml FGF2 for 5 days before they were harvested by Accutase treatment. Roughly 1x10e5 cells were then seeded into one well of a 48 well plate in DF3S+N2B27. Chemical treatment started on the same day (day 0). Samples are collected at indicated time points by lysing cells directly on plate with 150ul RLT buffer. Chemical information can be found a separate sheet.
Machine learning to predict developmental neurotoxicity with high-throughput data from 2D bio-engineered tissues.
Cell line, Subject, Compound, Time
View SamplesTwo-year rodent bioassays play a central role in evaluating both the carcinogenic potential of a chemical and generating quantitative information on the dose-response behavior for chemical risk assessments. The bioassays involved are expensive and time-consuming, requiring nearly lifetime exposures (two years) in mice and rats and costing $2 to $4 million per chemical. Since there are approximately 80,000 chemicals registered for commercial use in the United States and 2,000 more are added each year, applying animal bioassays to all chemicals of concern is clearly impossible. To efficiently and economically identify carcinogens prior to widespread use and human exposure, alternatives to the two-year rodent bioassay must be developed. In this study, animals were exposed for 13 weeks to two chemicals that were positive for lung tumors in the two-year rodent bioassay, two chemicals that were negative for tumors, and two vehicle controls. Gene expression analysis was performed on the lungs of the animals to assess the potential for identifying gene expression biomarkers that can predict tumor formation in a two-year bioassay following a 13 week exposure.
A comparison of transcriptomic and metabonomic technologies for identifying biomarkers predictive of two-year rodent cancer bioassays.
Sex, Age, Subject
View SamplesTwo-year rodent bioassays play a central role in evaluating both the carcinogenic potential of a chemical and generating quantitative information on the dose-response behavior for chemical risk assessments. The bioassays involved are expensive and time-consuming, requiring nearly lifetime exposures (two years) in mice and rats and costing $2 to $4 million per chemical. Since there are approximately 80,000 chemicals registered for commercial use in the United States and 2,000 more are added each year, applying animal bioassays to all chemicals of concern is clearly impossible. To efficiently and economically identify carcinogens prior to widespread use and human exposure, alternatives to the two-year rodent bioassay must be developed. In this study, animals were exposed for 13 weeks to two chemicals that were positive for liver tumors in the two-year rodent bioassay, two chemicals that were negative for liver tumors, and two vehicle controls. Gene expression analysis was performed on the livers of the animals to assess the potential for identifying gene expression biomarkers that can predict tumor formation in a two-year bioassay following a 13 week exposure.
A comparison of transcriptomic and metabonomic technologies for identifying biomarkers predictive of two-year rodent cancer bioassays.
Sex, Age, Subject
View SamplesMitochondria are centers of metabolism and signaling whose content and function must adapt to changing cellular environments. The biological signals that initiate mitochondrial restructuring and the cellular processes that drive this adaptive response are largely obscure. To better define these systems, we performed matched quantitative genomic and proteomic analyses of mouse muscle cells as they performed mitochondrial biogenesis. We find that proteins involved in cellular iron homeostasis are highly coordinated with this process, and that depletion of cellular iron results in a rapid, dose-dependent decrease of select mitochondrial protein levels and oxidative capacity. We further show that this process is universal across a broad range of cell types and fully reversed when iron is reintroduced. Collectively, our work reveals that cellular iron is a key regulator of mitochondrial biogenesis, and provides quantitative datasets that can be leveraged to explore post-transcriptional and post-translational processes that are essential for mitochondrial adaptation.
Complementary RNA and protein profiling identifies iron as a key regulator of mitochondrial biogenesis.
Cell line, Treatment
View SamplesWe sequenced mRNA in grossly enlarged testes from 1-year-old Stra8-deficient mice, and in testes from adult male wild-type controls, to verify that Stra8-deficient testes are enriched for genes normally expressed in type A spermatogonia. Overall design: Examination of mRNA levels in 6 whole-testis samples (3 replicates of each genotype). Specifically, we sequenced mRNA in grossly enlarged testes from three 1-year-old Stra8-deficient male mice, and in normal testes from three adult male wild-type controls
Periodic retinoic acid-STRA8 signaling intersects with periodic germ-cell competencies to regulate spermatogenesis.
No sample metadata fields
View SamplesAlthough HSF1 is known to play an important role in regulating the cellular response to proteotoxic stressors, little is known about the structure and function of the HSF1 signaling network under both stressed and unstressed conditions. In this study, we used a combination of chromatin immunoprecipitation (ChIP) microarray analysis and time course gene expression microarray analysis with and without siRNA-mediated inhibition of HSF1 comprehensively identify genes directly and indirectly regulated by HSF1 and examine the structure of the extended HSF1 signaling network. Correlation between promoter binding and gene expression was not significant for all genes bound by HSF1 suggesting that HSF1 binding per se is not sufficient for expression. However, the correlation with promoter binding was significant for genes identified as HSF1-regulated following siRNA knockdown allowing the identification of direct transcriptional targets of HSF1. Among promoters bound by HSF1 following heat shock, a gene ontology (GO) analysis showed significant enrichment only in categories related to protein folding. In contrast, analysis of the extended HSF1 signaling network showed enrichment in a variety of categories related to protein folding, anti-apoptosis, RNA splicing, ubiquitination and others, highlighting a complex transcriptional program directly and indirectly regulated by HSF1.
Genome-wide analysis of human HSF1 signaling reveals a transcriptional program linked to cellular adaptation and survival.
No sample metadata fields
View SamplesWe recently reported the scalable in vitro production of functional stem cell-derived cells. Here we extend this approach to generate SC- cells from Type 1 diabetic patients (T1D), a cell type that is destroyed during disease progression and has not been possible to extensively study. These cells express cell markers, respond to glucose both in vitro and in vivo, prevent alloxan-induced diabetes in mice, and respond to anti-diabetic drugs. Furthermore, we use an in vitro disease model to demonstrate the cells respond to different forms of cell stress. Using these assays, we find no major differences in T1D SC- cells compared to SC- cells derived from non-diabetic patients (ND). These results show that T1D SC- cells can be used for the treatment of diabetes, drug screening, and the study of cell biology.
Generation of stem cell-derived β-cells from patients with type 1 diabetes.
Specimen part
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