Arabidopsis fc2-1 mutants fail to properly de-etiolate after a prolonged period in the dark. Our goal was to monitor whole genome expression during the first 2 hours of de-etiolation to determine the cuase of this growth arrest.
Ubiquitin facilitates a quality-control pathway that removes damaged chloroplasts.
Specimen part
View SamplesTissue-specific comparison of gene expression levels in T65H translocation mice, either with or without uniparental duplications of Chrs 7 & 11. Identification of highly differentially expressed transcripts.
Chromosome-wide identification of novel imprinted genes using microarrays and uniparental disomies.
Specimen part
View SamplesComparison of gene expression levels between MatDp(dist2) and PatDp(dist2) mice (newborn whole head). Identification of highly differentially expressed transcripts.
Transcript- and tissue-specific imprinting of a tumour suppressor gene.
Specimen part
View SamplesConsider the problem of designing a panel of complex biomarkers to predict a patient's health or disease state when one can pair his or her current test sample, called a target sample, with the patient's previously acquired healthy sample, called a reference sample. As contrasted to a population averaged reference, this reference sample is individualized. Automated predictor algorithms that compare and contrast the paired samples to each other could result in a new generation of test panels that compare to a person's healthy reference to enhance predictive accuracy. This study develops such an individualized predictor and illustrates the added value of including the healthy reference for design of predictive gene expression panels. The objective is to predict each subject's state of infection, e.g., neither exposed nor infected, exposed but not infected, pre-acute phase of infection, acute phase of infection, post-acute phase of infection. Using gene microarray data collected in a large-scale serially sampled respiratory virus challenge study, we quantify the diagnostic advantage of pairing a person's baseline reference with his or her target sample.
An individualized predictor of health and disease using paired reference and target samples.
Specimen part, Subject, Time
View SamplesAbstract
Evidence of a functional role for mast cells in the development of type 1 diabetes mellitus in the BioBreeding rat.
No sample metadata fields
View SamplesA persistent and non-resolving inflammatory response to accumulating A peptide species is a cardinal feature in the development of Alzheimer's disease (AD). In response to accumulating A peptide species, microglia, the innate immune cells of the brain, generate a toxic inflammatory response that accelerates synaptic and neuronal injury. Many pro-inflammatory signaling pathways are linked to progression of neurodegeneration. However, endogenous anti-inflammatory pathways capable of suppressing A-induced inflammation represent a relatively unexplored area.
Suppression of Alzheimer-associated inflammation by microglial prostaglandin-E2 EP4 receptor signaling.
Specimen part
View SamplesMicroarray Analysis of Space-flown Murine Thymus Tissue Reveals Changes in Gene Expression Regulating Stress and Glucocorticoid Receptors. We used microarrays to detail the gene expression of space-flown thymic tissue and identified distinct classes of up-regulated genes during this process. We report here microarray gene expression analysis in young adult C57BL/6NTac mice at 8 weeks of age after exposure to spaceflight aboard the space shuttle (STS-118) for a period of 13 days. Upon conclusion of the mission, thymus lobes were extracted from space flown mice (FLT) as well as age- and sex-matched ground control mice similarly housed in animal enclosure modules (AEM). mRNA was extracted and an automated array analysis for gene expression was performed. Examination of the microarray data revealed 970 individual probes that had a 1.5 fold or greater change. When these data were averaged (n=4), we identified 12 genes that were significantly up- or down-regulated by at least 1.5 fold after spaceflight (p0.05). Together, these data demonstrate that spaceflight induces significant changes in the thymic mRNA expression of genes that regulate stress, glucocorticoid receptor metabolism, and T cell signaling activity. These data explain, in part, the reported systemic compromise of the immune system after exposure to the microgravity of space.
Microarray analysis of spaceflown murine thymus tissue reveals changes in gene expression regulating stress and glucocorticoid receptors.
Specimen part
View SamplesMesenchymal stromal cells (MSC) are currently being evaluated in numerous preclinical and clinical cell-based therapy studies. Furthermore, there is an increasing interest in exploring alternative uses of these cells in disease modelling, pharmaceutical screening and regenerative medicine by applying reprogramming technologies. However, the limited availability of MSCs from various sources, restricts their use. Term amniotic fluid has been proposed as an alternative source of MSCs. Previously, only low volumes of term fluid and its cellular constituents have been collected, and current knowledge of the MSCs derived from this fluid is limited. In this study, we collected amniotic fluid at term using a novel collection system and evaluated amniotic fluid MSC content and their characteristics, including their feasibility to undergo cellular reprogramming.
Term amniotic fluid: an unexploited reserve of mesenchymal stromal cells for reprogramming and potential cell therapy applications.
Specimen part
View SamplesThe transcriptional responses of human hosts towards influenza viral pathogens are important for understanding virus-mediated immunopathology. Despite great advances gained through studies using model organisms, the complete temporal host transcriptional responses in a natural human system are poorly understood. In a human challenge study using live influenza (H3N2/Wisconsin) viruses, we conducted a clinically uninformed (unsupervised) factor analysis on gene expression profiles and established an ab initio molecular signature that strongly correlates to symptomatic clinical disease. This is followed by the identification of 42 biomarkers whose expression patterns best differentiate early from late phases of infection. In parallel, a clinically informed (supervised) analysis revealed over-stimulation of multiple viral sensing pathways in symptomatic hosts and linked their temporal trajectory with development of diverse clinical signs and symptoms. The resultant inflammatory cytokine profiles were shown to contribute to the pathogenesis because their significant increase preceded disease manifestation by 36 hours. In subclinical asymptomatic hosts, we discovered strong transcriptional regulation of genes involved in inflammasome activation, genes encoding virus interacting proteins, and evidence of active anti-oxidant and cell-mediated innate immune response. Taken together, our findings offer insights into influenza virus-induced pathogenesis and provide a valuable tool for disease monitoring and management in natural environments.
Temporal dynamics of host molecular responses differentiate symptomatic and asymptomatic influenza a infection.
Specimen part
View SamplesNuclear receptor activation in liver leads to coordinated alteration of the expression of multiple gene products with attendant phenotypic changes of hepatocytes. Peroxisome proliferators including endogenous fatty acids, environmental chemicals, and drugs induce a multi-enzyme metabolic response that affects lipid and fatty acid processing. We studied the signaling network for the peroxisome proliferator-associated receptor alpha (PPAR) in primary human hepatocytes using the selective PPAR ligand, GW7647. We measured gene expression over multiple concentrations and times and conducted ChIP-seq studies at 2 and 24 hours to assess genomic binding of PPAR. Over all treatments there were 192 genes differentially expressed. Of these only 51% showed evidence of PPAR binding either directly at PPAR response elements or via alternative mechanisms. Almost half of regulated genes had no PPAR binding. We then developed two novel bioinformatics methods to visualize the dose-dependent activation of both the transcription factor circuitry for PPAR and the downstream metabolic network in relation to functional annotation categories. Available databases identified several key transcription factors involved with the non-genomic targets after GW7647 treatment, including SP1, STAT1, ETS1, ER, and HNF4. The linkage from PPAR binding through gene expression likely requires intermediate protein kinases to activate these transcription factors. We found enrichment of functional annotation categories for organic acid metabolism and cell lipid metabolism among the differentially expressed genes. Lipid transport processes showed enrichment at the highest concentration of GW7647 (10M). While our strategy for mapping transcriptional networks is evolving, these approaches are necessary in moving from toxicogenomic methods that derive signatures of activity to methods that establish pathway structure, showing the coordination of the activated nuclear receptor with other signaling pathways.
A map of the PPARα transcription regulatory network for primary human hepatocytes.
Age, Subject
View Samples