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GSE21893
Escherichia coli
4 Downloadable Samples
Affymetrix E. coli Genome 2.0 Array (ecoli2)
Description
Avian pathogenic Escherichia coli strains frequently cause extra-intestinal infections and are responsible for significant economic losses in the poultry industry worldwide. APEC isolates are closely related to human extraintestinal pathogenic E.coli strains and may also act as pathogens for humans. In this work, three type VI secretion systems were deleted to analyze which pathogenicity characteristics would change in the mutants, compared to wild type strain (SEPT 362).
Publication Title
The type VI secretion system plays a role in type 1 fimbria expression and pathogenesis of an avian pathogenic Escherichia coli strain.
Sample Metadata Fields
No sample metadata fields
View Samples- Rattus norvegicus
- 8 Downloadable Samples
Illumina HiSeq 2000
Description
In rats, learning and memory performance decline during normal aging, which makes this rodent species a suitable model to evaluate therapeutic strategies. In aging rats, insulin-like growth factor-I (IGF-I), is known to significantly improve spatial memory accuracy as compared to control counterparts. A constellation of gene expression changes underlie the hippocampal phenotype of aging but no studies on the effects of IGF-I on the hippocampal transcriptome of old rodents have been documented. Here, we assessed the effects of IGF-I gene therapy on spatial memory performance in old female rats and compared them with changes in the hippocampal transcriptome. Overall design: Hippocampal RNA-Seq profiles of 28 months old rats intracerebroventricularly injected with an adenovector expressing rat IGF-I was compared with placebo adenovector-injected counterparts (4 samples each group)
Publication Title
IGF-I Gene Therapy in Aging Rats Modulates Hippocampal Genes Relevant to Memory Function.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Although new therapies have doubled the survival of multiple myeloma (MM) patients, this remains an incurable disease. It has been postulated that the so-called MM Cancer Stem Cells (MM-CSC) would be responsible for tumor initiation and relapse but their unequivocal identification remains unclear. Here, we investigated in a panel of MM cell lines the presence of CD20+ cells harboring a MM-CSC phenotype. Among the multiple cell lines investigated, only a small population of CD20dim+ cells (0.3%) in the RPMI-8226 cell line was found. CD20dim+ RPMI-8226 cells expressed the plasma cell markers CD38 and CD138 and were CD19-CD27-. Additionally, CD20dim+ RPMI-8226 cells did not exhibit stem-cell markers as shown by gene expression profiling and the aldehyde dehydrogenase (ALDH) assay. Moreover, we demonstrated that CD20dim+ RPMI-8226 cells are not essential for CB17-SCID mice engraftment and show lower self-renewal potential than the CD20- RPMI-8226 cells. These results do not support CD20+ expression for the identification of MM-CSC.
Publication Title
CD20 positive cells are undetectable in the majority of multiple myeloma cell lines and are not associated with a cancer stem cell phenotype.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Despite recent advances in the treatment of multiple myeloma (MM), it remains an incurable disease potentially due to the presence of resistant myeloma cancer stem cells (MM-CSC). Although the presence of clonogenic cells in MM was described more than 30 years ago, the phenotype of MM-CSC is still a matter of debate, especially with respect to the expression of syndecan- 1 (CD138). Here, we demonstrate the presence of two subpopulations - CD138++ (95-99%) and CD138low (1-5%) - in eight MM cell lines. To find out possible stem-cell-like features, we have phenotypically, genomic and functionally characterized the two subpopulations. Our results show that the minor CD138low subpopulation is morphologically identical to the CD138++ fraction and does not represent a more immature B-cell compartment (with lack of CD19, CD20 and CD27 surface expression). Moreover, both subpopulations have similar gene expression and genomic profiles. Importantly, both CD138++ and CD138low subpopulations have similar sensitivity to bortezomib, melphalan and doxorubicin. Finally, serial engraftment in SCID mice shows that CD138++ as well as CD138low cells have self-renewal potential and they are also phenotypically interconvertible. Overall, our results differ from previously published data which attribute a B-cell phenotype to MM-CSC and urge the need to explore more reliable markers to discriminate true clonogenic myeloma cells.
Publication Title
Phenotypic, genomic and functional characterization reveals no differences between CD138++ and CD138low subpopulations in multiple myeloma cell lines.
Sample Metadata Fields
Disease, Cell line
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
Astrocytes react to brain injury in a heterogeneous manner with only a subset resuming proliferation and acquiring in vitro neural stem cell properties. In order to identify novel regulators of this astrocyte subset, we performed a genome-wide expression analysis of reactive astrocytes isolated 5 days after stab wound injury from the adult mouse cerebral cortex. The expression pattern was compared with astrocytes from normal cortex and adult neural stem cells isolated from the sub-ependymal zone (GSE18765). These comparisons revealed a set of genes up-regulated both in neurogenic neural stem cells and reactive astrocytes, including the lectins Galectin-1 and -3. These results, as well as the pattern of Galectin expression in the lesioned brain, led us to examine the functional significance of these lectins in brains of Galectin-1/3 double-knockout mice.
Publication Title
Astrocyte reactivity after brain injury-: The role of galectins 1 and 3.
Sample Metadata Fields
Sex, Specimen part, Treatment, Time
View Samples- Homo sapiens
- 2 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
The discovery of mammalian cardiac progenitor cells has suggested that the heart consists of not only terminally differentiated beating cardiomyocytes, but also a population of self-renewing stem cells with the potential to generate new cardiomyocytes (Anderson, Self et al. 2007; Bearzi, Rota et al. 2007; Wu, Chien et al. 2008). A consequence of longevity is continual exposure to environmental and xenobiotic stresses, and recent literature suggests that hematopoietic stem cell pools tightly control cell health through upregulation of the integrated stress response and consequent cellular mechanisms such as apoptosis. However, whether or not this biological response is conserved in progenitor cells for later lineages of tissue specific stem cells is not well understood. Using human induced pluripotent stem cells (iPSC) of both cardiac progenitor and mature cardiomyocyte lineages, we found that the integrated stress response was upregulated in the iPSC cardiac progenitors leading to an increased sensitivity for apoptosis relative to the mature cardiomyocytes. Of interest, C/EBP homologous protein (CHOP) signaling plays a mechanistic role in the cell death phenotype observed in iPSC progenitors, by which depletion of CHOP prevents cell death following cellular stress by thapsigargin exposure. Our studies suggest that the integrated stress response plays a unique role in maintaining iPSC cardiac progenitor cellular integrity by removing unhealthy cells via apoptosis following environmental and xenobiotic stresses, thus preventing differentiation and self-renewal of damaged cells.
Publication Title
The Integrated Stress Response Regulates Cell Health of Cardiac Progenitors.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Mus musculus
- 5 Downloadable Samples
- Illumina Genome Analyzer IIx
Description
Regeneration of lung epithelium is vital for maintaining airway function and integrity. An imbalance between epithelial damage and repair is at the basis of numerous chronic lung diseases such as asthma, COPD, pulmonary fibrosis and lung cancer. IGF (Insulin-like Growth Factors) signaling has been associated with most of these respiratory pathologies, although their mechanisms of action in this tissue remain poorly understood. Expression profiles analyses of IGF system genes performed in mouse lung support their functional implication in pulmonary ontogeny. Immuno-localization revealed high expression levels of Igf1r (Insulin-like Growth Factor 1 Receptor) in lung epithelial cells, alveolar macrophages and smooth muscle. To further understand the role of Igf1r in pulmonary homeostasis, two distinct lung epithelial-specific Igf1r mutant mice were generated and studied. The lack of Igf1r disturbed airway epithelial differentiation in adult mice revealed enhanced proliferation and altered morphology in distal airway club cells. During recovery after naphthalene-induced club cell injury, the kinetics of terminal bronchiolar epithelium regeneration was hindered in Igf1r mutants, revealing increased proliferation and delayed differentiation of club and ciliated cells. Amid airway restoration, lungs of Igf1r deficient mice showed increased levels of Igf1, Insr, Igfbp3 and epithelial precursor markers, reduced amounts of Scgb1a1 protein, and alterations in IGF signaling mediators. These results support the role of Igf1r in controlling the kinetics of cell proliferation and differentiation during pulmonary airway epithelial regeneration after injury. Overall design: Lung mRNA profiles of 3 months-old Igf1rfl/fl normal/control transgenic mice were generated by deep sequencing using Illumina GAIIx. ------------------------------------------- Submitter states "we use data on the absolute transcription levels (FPKM) of same IGF system genes on the adult "normal" mouse lung to compare them with those reported in the human adult lung (expressed in both as FPKM) (http://www.proteinatlas.org/)".
Publication Title
Involvement of Igf1r in Bronchiolar Epithelial Regeneration: Role during Repair Kinetics after Selective Club Cell Ablation.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 12 Downloadable Samples
- Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
MicroRNAs (miRNAs) are short noncoding RNA molecules regulating the expression of mRNAs. Target identification of miRNAs is computationally difficult due to the relatively low homology between miRNAs and their targets. We present here an experimental approach to target identification where the cartilage-specific miR-140 was overexpressed and silenced in cells it is normally expressed in separate experiments. Expression of mRNAs was profiled in both experiments and the intersection of mRNAs repressed by miR-140 overexpression and derepressed by silencing of miR-140 was identified. The intersection contained only 49 genes, although both treatments affected the accumulation of hundreds of mRNAs. These 49 genes showed a very strong enrichment for the miR-140 seed sequence implying that the approach is efficient and specific. 21 of these 49 genes were predicted to be direct targets based on the presence of the seed sequence. Interestingly, none of these were predicted by the published target prediction methods we used. One of the potential target mRNAs, Cxcl12, was experimentally validated by Northern blot analysis and a luciferase reporter assay.
Publication Title
Experimental identification of microRNA-140 targets by silencing and overexpressing miR-140.
Sample Metadata Fields
No sample metadata fields
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Genome 430A 2.0 Array (mouse430a2)
Description
Insight into the role of Insulin-like Growth Factor (IGF) in development of lungs has come from the study of genetically modified mice. IGF1 is a key factor during lung development. IGF1 deficiency in the neonatal mouse causes respiratory failure collapsed alveoli and altered alveolar septa. To further characterize IGF1 function during lung development we analyzed Igf1-/- mouse prenatal lungs in a C57Bl/6 genetic background. Mutant lungs showed disproportional hypoplasia, disorganized extracellular matrix and dilated alveolar capillaries. IGF1 target genes during lung maturation were identified by analyzing RNA differential expression in Igf1-/- lungs using microarrays.
Publication Title
Transcriptome analysis in prenatal IGF1-deficient mice identifies molecular pathways and target genes involved in distal lung differentiation.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 5 Downloadable Samples
- IlluminaGenomeAnalyzerIIx
Description
Comparison of expression profile of Ewing''s sarcoma with cell of origin, mesenchymal stem cells with the goal of identifying novel therapeutic targets. Overall design: 3 Ewing''s cell lines compared to 2 MSC cell lines
Publication Title
Exploring the surfaceome of Ewing sarcoma identifies a new and unique therapeutic target.
Sample Metadata Fields
No sample metadata fields
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