Although it is well known that stroke and head trauma are one of the high risk factors for the development of acquired epilepsy, the cellular mechanisms underlying the epileptogenesis is not well understood. Using rodent models of ischemic stroke and head trauma (partial cortical isolation, undercut), we comparatively analyzed transcription profiles between two different models to explore the commonality.
TGFβ signaling is associated with changes in inflammatory gene expression and perineuronal net degradation around inhibitory neurons following various neurological insults.
Sex, Specimen part, Treatment, Time
View SamplesThe immortalized human urothelial cell line, UROtsa, was transformed in six parallel cultures with continual passaging in1 M Cd+2 until the cells were able to attain the ability to form colonies in soft agar and subcutaneous tumors in nude mice. The gene expression profiles between cadmium-transformed and control samples were compared and the differentially expressed genes were identified.
Variation of keratin 7 expression and other phenotypic characteristics of independent isolates of cadmium transformed human urothelial cells (UROtsa).
Cell line
View SamplesAlternative RNA splicing analysis in Hep3B cell cultured under 21% (N1,3,5) or 1.2% (H2,4,6) oxygen
Hypoxia regulates alternative splicing of HIF and non-HIF target genes.
Cell line
View SamplesA critical step in regeneration is recreating the cellular identities and patterns of lost organs long after embryogenesis is complete. In plants, perpetual (indeterminate) organ growth occurs in apical stem cell niches, which have been shown to re-establish quickly when damaged or removed (1,2). Here we ask whether the machinery of perpetual organ growth, stem cell activity, is needed for the phase of regeneration that leads to replenishing lost cell identities and patterning, or, whether organ re-establishment enlists a wider group of pluripotent cells. We adapt a root tip regeneration system to Arabidopsis that permits us to assess the molecular and functional recovery of specific cell fates during organ regeneration. These results suggest a rapid restoration of missing cell fate and function in advance of the recovery of stem cell activity. Surprisingly, plants with mutations that fail to maintain stem cell activity were able to re-pattern their distal tip and re-specify lost cell fates. Thus, although stem cell activity is required to resume indeterminate growth (3), our results show it is not necessary for cell re-specification and patterning steps. This implies a regeneration mechanism that coordinates patterning of the whole organ, as in embryogenesis, but is initiated from different starting morphologies. 1. Feldman, L. J. Denovo Origin of Quiescent Center Regenerating Root Apices of Zea-Mays. Planta 128, 207-212 (1976). 2. Xu, J. et al. A molecular framework for plant regeneration. Science 311, 385-8 (2006). 3. Gordon, S. P. et al. Pattern formation during de novo assembly of the Arabidopsis shoot meristem. Development 134, 3539-48 (2007).
Organ regeneration does not require a functional stem cell niche in plants.
No sample metadata fields
View SamplesMesenchymal stromal cells (MSCs) sense and modulate inflammation and represent potential clinical treatment for immune disorders. However, many details of the bidirectional interaction between MSCs and the innate immune comaprtment are still unsolved. Here we describe an unconventional but functional interaction between pro-inflammatory classically activated macrophages (M1M) and MSCs, with CD54 playing a central role. CD54 was upregulated and enriched specifically at the contact area between M1M and MSCs. Moreover, the specific interaction induced calcium signaling and increased the immunosuppressive capacities of MSCs dependent on CD54 mediation. Our data demonstrate that MSCs can detect an inflammatory microenvironment via a direct and physical interaction with innate immune cells. This finding opens new perspectives for MSC-based cell therapy.
CD54-Mediated Interaction with Pro-inflammatory Macrophages Increases the Immunosuppressive Function of Human Mesenchymal Stromal Cells.
Specimen part
View SamplesBone-marrow mesenchymal stem cells (MSCs) are plastic adherent cells that can differentiate into various tissue lineages, including osteoblasts, adipocytes and chondrocytes. However, this progenitor property is not shared by all cells within the MSC population. In addition, MSCs vary in their proliferation capacities and expression of markers. Because of heterogeneity of CD146 expression in the MSC population, we compared CD146-/Low and CD146High cells under clonal and non-clonal (sorted MSCs) conditions to determine whether this expression is associated with specific functions. CD146-/Low and CD146High MSCs did not differ in colony-forming unit-fibroblast number, osteogenic and adipogenic differentiation or in vitro hematopoietic supportive activity. However, CD146-/Low clones proliferated slightly but significantly faster than did CD146High clones. In addition, a strong expression of CD146 molecule was associated with a commitment towards a vascular smooth muscle cell lineage with upregulation of calponin-1 expression. Thus, within a bone-marrow MSC population, certain subpopulations characterized by high expression of CD146, are committed toward a vascular smooth muscle cell lineage.
CD146 expression on mesenchymal stem cells is associated with their vascular smooth muscle commitment.
Specimen part, Subject
View SamplesEnhanced understanding of differential gene expression and biological pathways associated with distinct phases of intramembranous bone regeneration following femoral marrow ablation surgery will improve future advancements regarding osseointegration of joint replacement implants, biomaterials design, and bone tissue engineering. A rat femoral marrow ablation model was performed and genome-wide microarray data were obtained from samples at 1, 3, 5, 7, 10, 14, 28, and 56 days post-ablation, with intact bones serving as controls at Day 0. Bayesian model-based clustering produced eight distinct groups amongst 9,062 significant gene probe sets based on similar temporal expression profiles, which were further categorized into three major temporal classes of increased, variable, and decreased expression. Differential biological processes and pathways associated with each major temporal group were identified, and significantly expressed genes involved were visually represented by heat maps. It was determined that the increased expression group exclusively contains genes involved in pathways for matrix metalloproteinases (MMPs), Wnt signaling, TGF- signaling, and inflammatory pathway. Only the variable expression group contains genes associated with glycolysis and gluconeogenesis, Notch Signaling Pathway, natural killer cell mediated cytotoxicity, and B cell receptor signaling pathway, among others. The decreased group exclusively consists of genes involved in heme biosynthesis, p53 signaling pathway, and hematopoietic cell lineage. Significant biological pathways and transcription factors expressed at each time point post-ablation were also identified.
Temporal gene expression profiling during rat femoral marrow ablation-induced intramembranous bone regeneration.
Sex, Specimen part, Time
View SamplesMuch has been learned about transcriptional cascades and networks from large-scale systems analyses of high-throughput data sets. However, analysis methods that optimize statistical power through simultaneous evaluation of thousands of ChIP-seq peaks or differentially expressed genes possess substantial limitations in their ability to uncover mechanistic principles of transcriptional control. By examining nascent transcript RNA-seq, ChIP-seq, and binding motif data sets from lipid A-stimulated macrophages with increased attention to the quantitative distribution of signals, we identified unexpected relationships between the in vivo binding properties of inducible transcription factors, motif strength, and transcription. Furthermore, rather than emphasizing common features of large clusters of co-regulated genes, our results highlight the extent to which unique mechanisms regulate individual genes with key biological functions. Our findings demonstrate the mechanistic value of stringent interrogation of well- defined sets of genes as a complement to broader systems analyses of transcriptional cascades and networks. Overall design: Bone marrow-derived macrophages derived from C57Bl/6, Myd88-/-, Trif-/-, Irf3-/-, Ifnar-/-, and RelA-/- mice were stimulated with lipid A; C57Bl/6 macrophages were stimulated with lipid A in the presence of MAPK inhibitors or cycloheximide, or stimulated with PAM3CSK4 for 0, 15, 30, 60, and 120 minutes, or stimulated with lipid A for 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, and 60 minutes. Two biological replicates were generated for each time point for each treatment type.
A Stringent Systems Approach Uncovers Gene-Specific Mechanisms Regulating Inflammation.
No sample metadata fields
View SamplesSandhoff disease, one of the GM2 gangliosidoses, is a lysosomal storage disorder characterized by the absence of b-hexosaminidase A and B activity and the concomitant lysosomal accumulation of its substrate, GM2 ganglioside. It features catastrophic neurodegeneration and death in early childhood. How the lysosomal accumulation of ganglioside might affect the early development of the nervous system is not understood. Recently, cerebral organoids derived from induced pluripotent stem (iPS) cells have illuminated early developmental events altered by disease processes. To develop an early neurodevelopmental model of Sandhoff disease, we first generated iPS cells from the fibroblasts of an infantile Sandhoff disease patient, then corrected one of the mutant HEXB alleles in those iPS cells with CRISPR/Cas9 genome-editing technology, thereby creating isogenic controls. Next, we used the parental Sandhoff disease iPS cells and isogenic HEXB-corrected iPS cell clones to generate cerebral organoids that modeled the first trimester of neurodevelopment. The Sandhoff disease organoids but not the HEXB-corrected organoids accumulated GM2 ganglioside, and exhibited increased size and cellular proliferation compared with the HEXB-corrected organoids. Whole-transcriptome analysis demonstrated that development was impaired in the Sandhoff disease organoids, suggesting that alterations in neuronal differentiation may occur during early development in the GM2 gangliosidoses Overall design: Sandhoff disease and corrected cerebral organoids grown for 8 and 10 weeks were analyzed: four samples at each time point, each consisting of 4–6 pooled organoids, for both Sandhoff and corrected. Whole transcriptome from Sandhoff disease and corrected organoids for both time points were generated by deep sequencing on an Illumina HiSeq 2500.
Cerebral organoids derived from Sandhoff disease-induced pluripotent stem cells exhibit impaired neurodifferentiation.
Specimen part, Subject
View SamplesWe have studied the plasma membrane protein phenotype of human culture-amplified and native Bone Marrow Mesenchymal Stem Cells (BM MSCs). We have found, using microarrays and flow cytometry, that cultured cells express specifically 113 transcripts and 17 proteins that were not detected in hematopoietic cells. These antigens define a lineage-homogenous cell population of mesenchymal cells, clearly distinct from the hematopoietic lineages, and distinguishable from other cultured skeletal mesenchymal cells (periosteal cells and synovial fibroblasts). Among the specific membrane proteins present on cultured MSCs, 9 allowed the isolation from BM mononuclear cells of a minute population of native MSCs. The enrichment in Colony-Forming Units-Fibroblasts was low for CD49b, CD90 and CD105, but high for CD73, CD130, CD146, CD200 and integrin alphaV/beta5. Additionally, the expression of CD73, CD146 and CD200 was down-regulated in differentiated cells. The new marker CD200, because of its specificity and immunomodulatory properties, deserves further in depth studies.
Specific plasma membrane protein phenotype of culture-amplified and native human bone marrow mesenchymal stem cells.
Sex, Age, Specimen part, Treatment
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