By investigating the germinal center (GC) formation in STAT6ko/WT bone marrow-mixed chimera we found that GC formation in type 2 immune responses is dependent on B cell intrinsic expression of IL-4/IL-13-induced genes. We therefore used microarrays to find Stat6 dependent genes that are important for germinal center formation and/or organization after infection with the nematode Nippostrongylus brasiliensis (N. brasiliensis).
B-cell-intrinsic STAT6 signaling controls germinal center formation.
Specimen part
View SamplesNon-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disorder in industrialized countries. Liver samples from morbidly obese patients (N=45) with all stages of NAFLD and controls (N=18) were analysed by array-based DNA methylation and mRNA expression profiling. NAFLD-specific expression and methylation differences were seen for nine genes coding for key enzymes in intermediate metabolism (including PC, ACLY, PLCG1) and insulin/insulin-like signalling (including IGF1, IGFBP2, PRKCE) and replicated by bisulfite pyrosequening (independent N=39). Transcription factor binding sites at NAFLD-specific CpG sites were >1000-fold enriched for ZNF274, PGC1A and SREBP2. Intra-individual comparison of liver biopsies before and after bariatric surgery showed NAFLD-associated methylation changes to be partially reversible. Post-bariatric and NAFLD-specific methylation signatures were clearly distinct both in gene-ontology and transcription factor binding site analyses, with >400-fold enrichment of NRF1, HSF1 and ESRRA sites. Our findings provide one of the first examples of treatment-induced epigenetic organ remodelling in humans.
DNA methylation analysis in nonalcoholic fatty liver disease suggests distinct disease-specific and remodeling signatures after bariatric surgery.
Sex, Age, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Nijmegen Breakage Syndrome fibroblasts and iPSCs: cellular models for uncovering disease-associated signaling pathways and establishing a screening platform for anti-oxidants.
Specimen part, Disease, Disease stage, Cell line
View SamplesNijmegen Breakage Syndrome (NBS) is a rare autosomal recessive genetic disorder, first described 1981 in Nijmegen, Holland. The characteristics of NBS include genomic instability (resulting in early onset of malignancies), premature aging, microcephaly and other growth retardations, immune deficiency, and impaired puberty and fertility in females. The consequence of these manifestations is a severe decrease in average life span, caused by cancer or infection of the respiratory and urinary tract. We reprogrammed fibroblasts from NBS patients into induced pluripotent stem cells (iPSCS) to bypass premature senescence and to generate an unlimited cell source for modeling purposes. We screened the influence of antioxidants on intracellular levels of ROS and DNA damage and found that EDHB was able to decrease DNA damage in the presence of high oxidative stress. Furthermore, we found that NBS fibroblasts, but not NBS-iPSCs were more susceptible to the induction of DNA damage than their normal counterparts. We performed global transcriptome analysis comparing NBS to normal fibroblasts and NBS-iPSCs to hESCs. There, we found, that TP53 was activated and cell cycle genes broadly down-regulated in NBS fibroblasts and up-regulation of glycolysis specifically in NBS-iPSCs.
Nijmegen Breakage Syndrome fibroblasts and iPSCs: cellular models for uncovering disease-associated signaling pathways and establishing a screening platform for anti-oxidants.
Specimen part, Disease, Disease stage, Cell line
View SamplesNijmegen Breakage Syndrome (NBS) is a rare autosomal recessive genetic disorder, first described 1981 in Nijmegen, Holland. The characteristics of NBS include genomic instability (resulting in early onset of malignancies), premature aging, microcephaly and other growth retardations, immune deficiency, and impaired puberty and fertility in females. The consequence of these manifestations is a severe decrease in average life span, caused by cancer or infection of the respiratory and urinary tract. We reprogrammed fibroblasts from NBS patients into induced pluripotent stem cells (iPSCS) to bypass premature senescence and to generate an unlimited cell source for modeling purposes. We screened the influence of antioxidants on intracellular levels of ROS and DNA damage and found that EDHB was able to decrease DNA damage in the presence of high oxidative stress. Furthermore, we found that NBS fibroblasts, but not NBS-iPSCs were more susceptible to the induction of DNA damage than their normal counterparts. We performed global transcriptome analysis comparing NBS to normal fibroblasts and NBS-iPSCs to hESCs. There, we found, that TP53 was activated and cell cycle genes broadly down-regulated in NBS fibroblasts and up-regulation of glycolysis specifically in NBS-iPSCs.
Nijmegen Breakage Syndrome fibroblasts and iPSCs: cellular models for uncovering disease-associated signaling pathways and establishing a screening platform for anti-oxidants.
Specimen part, Disease, Disease stage
View SamplesThe hepatitis E virus (HEV), a non enveloped RNA virus, causes viral hepatitis. The viral open reading frame 2 (ORF2) protein represents the capsid protein of HEV which is known to cause endoplasmic reticulum stress in ORF2 expressing cells. The initiation of endoplasmic reticulum stress induced apoptosis mainly involves the transcriptional activation of pro-apoptotic gene CHOP which will further trigger the major apoptotic pathways. However, the activation of CHOP by ORF2 protein in this study does not induce apoptotic markers such as Bax translocation to mitochondria. We have used the Affymetrix microarray platform to screen the pro-apoptotic effects induced by the expression of ORF2 protein in human hepatic cell lines (Huh7). The Huh7 cells were transduced either with recombinant adenovirus encoding the HEV ORF2 (Ad-ORF2) or an adenovirus encoding the green fluorescent protein (Ad-GFP). The array results consistently showed an ORF2 specific induction of mRNA corresponding to the chaperones Hsp72, Hsp70B and co-chaperone Hsp40. These studies provide further mechanisms of the ER stress mediated pro apoptotic effects caused by the ORF2 protein and its potential role for the activation of anti-apoptotic activity of the host cell.
Hepatitis E virus ORF2 protein activates the pro-apoptotic gene CHOP and anti-apoptotic heat shock proteins.
Cell line
View SamplesThe activation of hepatic stellate cells (HSC) plays a crucial role in non-alcoholic fatty liver disease (NAFLD), which could further develop to non-alcoholic steatohepatitis (NASH) and liver fibrosis/cirrhosis. Since cGMP-dependent protein kinase 1 (cGK1) deficient (cGK1-KO) mice displayed hepatic insulin resistance we hypothesized that cGK1 modulates HSC activation and its metabolic consequences. First, retinol storage and gene expression were studied in cGK1-KO mice. Second, we investigated the effects of cGK1-silencing on gene expression in the human stellate cell line LX2. Finally, cGK1 expression was investigated in human liver biopsies covering a wide range of liver fat content. Retinyl-ester level in the liver of cGK1-KO mice was lower compared to wild-type animals, which was associated with increased inflammatory gene expression. mRNA regulation in cGK1-silenced LX2 cells showed stronger stellate cell activation profile, altered matrix degradation and elevated chemokine level. On the other hand, activation of LX2 cells suppressed cGK1 expression, which was associated with human data, showing a negative correlation between cGK1 mRNA and liver fat content in liver biopsies. These results suggest that the lack of cGK1 could possibly lead to stellate cell activation, which elevates chemokine expression and inflammatory processes, which in turn disturbs hepatic insulin sensitivity.
No associated publication
Sex, Specimen part
View SamplesDCs are localized under the mucosa of the lungs and the gastrointestinal tract, and therefore come into close contact with A. fumigatus germ tubes during early steps of infection as soon as fungi become invasive. For a more detailed insight into differentially regulated genes, whole genome microarray analysis was performed.
Impact of mycophenolic acid on the functionality of human polymorphonuclear neutrophils and dendritic cells during interaction with Aspergillus fumigatus.
No sample metadata fields
View SamplesMycobacteria can survive and persist in macrophages despite triggering multiple pattern recognition receptors and strong T cell-derived IFN-gamma production. The mycobacterial cord factor trehalose-6,6-dimycolate binds the C-type lectin receptor Mincle and induces inflammatory gene expression through the Syk-Card9 pathway. It is well established that TDM and IFN-gamma synergize to induce expression of iNOS. However, the cord factor may also act to down-regulate IFN-gamma-induced responses and contribute to mycobacterial immune evasion.
No associated publication
Sex, Specimen part
View SamplesImpaired post-ischemic angiogenesis in rats with chronic kidney disease: underlying changes in ischemia-induced early regulation of gene expression
No associated publication
Specimen part
View Samples