Surface topography impacts on cell growth and differentiation, but it is not trivial to generate homogeneous surface structures and to define the specific morphological parameters of relevance. In this study, we have compared gene expression profiles of mesenchymal stem cells (MSCs) on nanostructured groove/ridge surfaces. Patterns were generated in polyimide using multi beam laser interference. These structures affected cell size and orientation of human MSCs. Furthermore, the nano-patterns with a periodicity of 650 nm increased differentiation towards osteogenic and adipogenic lineages. However, in absence of differentiation media the surface structures did neither induce differentiation, nor lineage-specific gene expression changes as assessed by genome wide gene expression profiles with Affymetrix microarray technology. Our results demonstrate that grooves and ridges at a periodicity of 650 nm enhance the propensity of MSCs to differentiate towards adipogenic and/or osteogenic lineages but they do not directly govern lineage-specific gene expression changes.
Surface topography enhances differentiation of mesenchymal stem cells towards osteogenic and adipogenic lineages.
Specimen part, Subject
View SamplesWe have identified desmoglein 2 (DSG2) as the primary high-affinity receptor used by adenovirus (Ad) serotypes Ad3, Ad7, and Ad14. These serotypes represent important human pathogens causing respiratory tract infections. In epithelial cells, adenovirus binding to DSG2 triggers events reminiscent of epithelial-to-mesenchymal transition, leading to transient opening of intercellular junctions. This improves access to receptors, e.g. CD46 and Her2/neu, that are trapped in intercellular junctions. In addition to complete virions, dodecahedral particles (PtDd) formed by viral penton and fiber in excess during viral replication, can trigger DSG2-mediated opening of intercellular junctions as shown by studies with recombinant Ad3 PtDd. Our findings shed light on adenovirus biology and pathogenesis and have implications for cancer therapy.
Desmoglein 2 is a receptor for adenovirus serotypes 3, 7, 11 and 14.
Specimen part
View SamplesHeterozygous and homozygous Pax2 E11.5 embryos were collected and the intermediate mesoderm was dissected and dispersed into single cells.
Evidence for intermediate mesoderm and kidney progenitor cell specification by Pax2 and PTIP dependent mechanisms.
Specimen part
View SamplesEpstein-Barr virus (EBV) is a ubiquitous gammaherpes virus that establishes a life-long latency in over 90% of the world's population. Epstein Barr Nuclear Antigen 1, EBNA1, is the only viral protein consistently detected in all viral latency programs, as well as in all forms of EBV-associated malignancies. EBNA1 plays critical roles in the viral life cycle by fostering the replication and maintenance of the extrachromosomal viral genome as well as enhancing transcription from multiple viral promoters.
Identifying sites bound by Epstein-Barr virus nuclear antigen 1 (EBNA1) in the human genome: defining a position-weighted matrix to predict sites bound by EBNA1 in viral genomes.
No sample metadata fields
View SamplesThe first in vitro tests for developmental toxicity made use of rodent cells. Newer teratology tests, e.g. developed during the ESNATS project, use human cells and measure mechanistic endpoints (such as transcriptome changes). However, the toxicological implications of mechanistic parameters are hard to judge, without functional/morphological endpoints. To address this issue, we developed a new version of the human stem cell-based test STOP-tox(UKN). For this purpose, the capacity of the cells to self-organize to neural rosettes was assessed as functional endpoint: pluripotent stem cells were allowed to differentiate to neuroepithelial cells for six days in the presence or absence of toxicants. Then, both transcriptome changes were measured (standard STOP-tox(UKN)), and cells were allowed to form rosettes. After optimization of staining methods, an imaging algorithm for rosette quantification was implemented and used for an automated rosette formation assay (RoFA). Neural tube toxicants (like valproic acid), which are known to disturb human development at stages when rosette-forming cells are present, were used as positive controls. Established toxicants led to distinctly different tissue organization and differentiation stages. RoFA outcome and transcript changes largely correlated concerning (i) the concentration-dependence, (ii) the time-dependence, and (iii) the set of positive hits identified amongst 24 potential toxicants. Using such comparative data, a prediction model for the RoFA was developed. The comparative analysis was also used to identify gene dysregulations that are particularly predictive for disturbed rosette formation. This ‘RoFA predictor gene set’ may be used for a simplified and less costly setup of the STOP-tox(UKN) assay.
Development of a neural rosette formation assay (RoFA) to identify neurodevelopmental toxicants and to characterize their transcriptome disturbances.
Sex, Specimen part, Cell line, Treatment
View SamplesLiver RNA was collected from three genotypes: WT controls, KCP knockout (KCP-KO) mutants, and KCP-Transgenic (KCP-Tg) overexpressing mice.
The kielin/chordin-like protein KCP attenuates nonalcoholic fatty liver disease in mice.
Specimen part
View SamplesGlomerular RNA comparison between wild-type and podocyte specific deletion of the PTIP gene in 1 month old kidneys. The PTIP gene was deleted using a floxed allele and a Podocin-Cre driver strain.
Altering a histone H3K4 methylation pathway in glomerular podocytes promotes a chronic disease phenotype.
Specimen part
View SamplesGene expression profiles of peripheral blood samples from C57BL/6 mice exposed with ionizing radiation.
Biological pathway selection through Bayesian integrative modeling.
Sex, Specimen part, Treatment, Time
View SamplesLesions of chronic idiopathic urticaria (CIU) showed significant up-regulation of 506 genes and reduced expression of 51 genes.
Gene expression profiles in chronic idiopathic (spontaneous) urticaria.
Specimen part, Subject
View SamplesBacteria are extremely versatile organisms which rapidly adapt to changing environments. When Escherichia coli cells switch from planktonic growth to biofilm, flagellum formation is turned off, and the production of fimbriae and extracellular polysaccharides is switched on. Here we show that BolA protein is a new bacterial transcription factor which modulates the switch from planktonic to sessile lifestyle. BolA negatively modulates flagella biosynthesis and thus swimming capacity. Furthermore, BolA overexpression favors biofilm formation and involvesinvolving fimbriae-like adhesins and curli production. Our results unraveled for the first time that BolA is a protein with high affinity to DNA, involved in the regulation of several genes of E. coli at a genome-wide scale level. Moreover, this observation further demonstrated that the most significant targets of this protein involved a complex network of genes encoding proteins extremely necessary in biofilm development processes. Herein we propose that BolA is a motile/adhesive transcriptional switch, specifically involved in the transition between the planktonic and the attachment stage of biofilm formation process.
BolA is a transcriptional switch that turns off motility and turns on biofilm development.
No sample metadata fields
View Samples