Thymic epithelial cells (TECs) are essential for thymopoiesis and form a complex three-dimensional network, the organization of which is strikingly different from other epithelia. Interestingly, TECs express simple epithelia keratins in the cortex, stratified epithelia keratins in the medulla and epidermal differentiation markers in Hassall's bodies. Here we investigate the relationship between thymic epithelium and epidermal differentiation and show that the thymus of the rat contains a population of clonogenic TECs that can be extensively cultured and cloned using conditions developed for epidermal cell therapy in human. Clonogenic TECs conserve a thymic identity and the capacity to integrate in a thymic epithelial network, but they acquire new functionalities when exposed to an inductive skin microenvironment, permanently adopting the fate of hair follicle multipotent stem cells. This change in fate, maintained over time in serial transplantation, correlates with a down-regulation of transcription factors important for thymic identity, and an up-regulation of epidermal markers. Consequently, the TECs capacity to integrate in a thymic epithelial network is altered or even lost. Our results demonstrate that the thymus contains a population of holoclone-like epithelial cells that can function as bona fide multipotent keratinocyte stem cells, and that microenvironmental cues are sufficient to re-direct epithelial-cell fate, allowing crossing of primitive germ layer boundaries from endoderm to ectoderm.
Microenvironmental reprogramming of thymic epithelial cells to skin multipotent stem cells.
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View SamplesWe have investigated the p53-dependent stress response in medium spiny neurons (MSNs) that degenerate in Huntingtons disease. To induce p53 signaling cascade, we have genetically inactivated by the Cre/loxP system the essential RNA polymerase I (Pol I) transcription factor TIF-IA, leading to stabilization of p53 and induction of p53-dependent apoptosis.
A neuroprotective phase precedes striatal degeneration upon nucleolar stress.
Age, Specimen part
View SamplesMesoangioblasts are vessel-associated progenitor cells that show therapeutic promise for the treatment of muscular dystrophy. Mesoangioblasts have the ability to undergo skeletal muscle differentiation and cross the blood vessel wall regardless of the developmental stage at which they are isolated. Here we show that PW1/Peg3 is expressed at high levels in mesoangioblasts obtained from mouse, dog and human tissues and its level of expression correlates with their myogenic competence. Silencing PW1/Peg3 markedly inhibits myogenic potential of mesoangioblasts in vitro through MyoD degradation. Moreover, lack of PW1/Peg3 abrogates mesoangioblast ability to cross the vessel wall and to engraft into damaged myofibers through the modulation of the junctional adhesion molecule-A. We conclude that PW1/Peg3 function is essential for conferring proper mesoangioblast competence and that the determination of PW1/Peg3 levels in human mesoangioblasts may serve as a biomarker to identify the best donor populations for therapeutic application in muscular dystrophies.
PW1/Peg3 expression regulates key properties that determine mesoangioblast stem cell competence.
Sex, Specimen part
View SamplesPrimary human foreskin fibroblasts (HFF) were infected with wild-type simplex virus 1 (HSV-1) strain 17 at a multiplicity of infection (MOI) of 10. Newly transcribed RNA was labelled by adding 500µM 4-thiouridine (4sU) to the cell culture media for 1h. Total cellular RNA was isolated using Trizol. Newly transcribed RNA was purified following the protocol described in Raedle et al. JoVE 2013. Overall design: Newly transcribed RNA was labelled in one hour intervals during the first eight hours of HSV-1 infection. All nine 4sU-RNA samples as well as total cellular RNA of every second hour of infection were sent for sequencing. Two independent biological replicates were analysed.
Prediction of Poly(A) Sites by Poly(A) Read Mapping.
No sample metadata fields
View SamplesPrimary human foreskin fibroblasts (HFF) were infected with wild-type simplex virus 1 (HSV-1) strain 17 at a multiplicity of infection (MOI) of 10. Ribosome profiling was performed at various times during infection with minor modification to the protocol described in Stern-Ginossar N et al., Science 2012 Overall design: Ribosome profiling was performed a 0, 1, 2, 4, 6 and 8 h post infection. Two biological replicates were analysed.
Widespread disruption of host transcription termination in HSV-1 infection.
No sample metadata fields
View SamplesIn order to comprehensively identify RNA-expression changes after p53-activation, total RNA was isolated and subjected to next generation seqencing (RNA-Seq) after activation of a conditional p53 allele in SW480 cells. Overall design: SW480/pRTR-p53-VSV cells were subjected to RNA-Seq analysis after 48 hours doxycycline-treatment.
p53-Regulated Networks of Protein, mRNA, miRNA, and lncRNA Expression Revealed by Integrated Pulsed Stable Isotope Labeling With Amino Acids in Cell Culture (pSILAC) and Next Generation Sequencing (NGS) Analyses.
No sample metadata fields
View SamplesExpression data from NIH-3T3 cells left uninfected or infected with MCMV for 2, 4 or 6h on total RNA as well as newly transcribed RNA labeled for 1-2, 3-4, and 5-6hpi. For newly transcribed RNA, the isolated RNA was labeled for 1h and separated from total cellular RNA following Trizol RNA preparation and thiol-specific biotinylation. We used microarrays to analyze the effects of MCMV infection in total and newly transcribed RNA.
Real-time transcriptional profiling of cellular and viral gene expression during lytic cytomegalovirus infection.
Disease, Cell line, Time
View SamplesThe apical junctional complex (AJC), composed of tight junctions and adherens junctions, is essential for maintaining epithelial barrier function. Since cigarette smoking and chronic obstructive pulmonary disease (COPD), the major smoking-induced disease, are both associated with increased lung epithelial permeability, we hypothesized that smoking alters the transcriptional program regulating AJC integrity in the small airway epithelium (SAE), the primary site of pathological changes in COPD. Transcriptome analysis revealed a global down-regulation of physiological AJC gene expression in the SAE of healthy smokers (n=53) compared to healthy nonsmokers (n=59), an observation associated with changes in molecular pathways regulating epithelial differentiation such as PTEN signaling and accompanied by induction of cancer-related AJC genes. Genome-wide co-expression analysis identified a smoking-sensitive AJC transcriptional network. The overall expression of AJC-associated genes was further decreased in COPD smokers (n=23). Exposure of human airway epithelial cells to cigarette smoke extract in vitro resulted in down-regulation of several AJC-related genes, accompanied by decreased transepithelial resistance. Thus, cigarette smoking alters the AJC gene expression architecture in the human airway epithelium, providing a molecular basis for the dysregulation of airway epithelial barrier function during the development of smoking-induced lung disease.
Cigarette smoking reprograms apical junctional complex molecular architecture in the human airway epithelium in vivo.
Sex, Age
View SamplesPurpose: study the role of MALT1 auto-proteolysis in T cell receptor mediated activation of NF-kB. Methods: Jurkat cells were generated that express wild type MALT1, the auto-cleavage deficient MALT1-R149A mutant, the catalytic inactive MALT1-C464A mutant or the R149A-C464A double mutant (RACA). Expression of endogenous MALT1 was inactivated using TALEN technology for the Jurkat cells expressing MALT1-R149A (JDM-RA) and MALT1-C464A (JDM-CA). Illumina HISeq 2000 deep sequencing was performed to determine the mRNA profiles for MALT1, JDM-RA, JDM-CA and RACA cells in unstimulated conditions or after treatment with 75ng/ml PMA and 150 ng/ml ionomycin for 3 or 18 hrs. Results: PMA ionomycin stimulation of the MALT1 auto-cleavage defective JDM-RA cells fails to activate NF-kB-dependent transcription like for the MALT1 catalytic inactive JDM-CA cells and the double RACA mutant cells. Conclusion: MALT1 autoproteolysis is essential for transcription of NF-kB target genes Overall design: mRNA profiles of Jurkat expressing MALT1, MALT1-R149A, MALT1-C464A and MALT1-R149A-C464A after 0, 3 and 18 hours of stimulation with PMA and Ionomycin were generated by deep sequencing, in duplicate, using Illumina HISeq 2000
MALT1 auto-proteolysis is essential for NF-κB-dependent gene transcription in activated lymphocytes.
No sample metadata fields
View SamplesIn this study, we evaluated global Mtb-induced gene expression in airway immune cells obtained by bronchoalveolar lavage of individuals with latent tuberculosis infection (LTBI) and in Mtb-naïve control subjects
<i>Mycobacterium tuberculosis</i>-Induced Bronchoalveolar Lavage Gene Expression Signature in Latent Tuberculosis Infection Is Dominated by Pleiotropic Effects of CD4<sup>+</sup> T Cell-Dependent IFN-γ Production despite the Presence of Polyfunctional T Cells within the Airways.
Specimen part, Disease
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