The response of human neutrophils to the emerging pathogen Mycobacterium abscessus has not been described. However, M. abscessus infections are frequently associated with neutrophil-rich abscesses. To better understand the reponse of neutrophils to M. abscessus we performed gene expression analysis using Affymetrix HG-U133A Plus 2.0 microarrays. Human neutrophils from healthy donors were stimulated with isogenic rough and smooth morphotypes of M. abscessus. Staphylococcus aureus was used as a control. Gene expression was compared to neutrophils left unstimulated. Neutrophils from four individual donors were isolated on separate days and stimulated with freshly prepared bacteria. Neutrophils (stimulated and control) were left for 2 hours before total RNA was isolated, and biotinylated cRNA was prepared by standard methods. Analysis indicates that M. abscessus morphotypes induce a limited number of genes, when compared to S. aureus, which are enriched in genes for cytokines and chemokines, including neutrophil-specific chemokines. These data suggest that neutrophils have a limited response to M. abscessus, which may contribute to neutrophil-rich abscess formation.overall_design = Human neutrophils from healthy donors were exposed to rough Mab (ATCC 19977T), smooth Mab (ATCC 19977T) and S. aureus (CF clinical strain) for two hours; control cells were exposed to saline.
Mycobacterium abscessus induces a limited pattern of neutrophil activation that promotes pathogen survival.
Specimen part, Disease, Treatment
View SamplesOesophageal exposure to duodenogastroesophageal refluxate is implicated in the development of Barretts Metaplasia, with increased risk of progression to oesophageal adenocarcinoma. The literature proposes that reflux exposure activates NF-kB, driving the aberrant expression of intestine-specific caudal-related homeobox genes. However, early events in the pathogenesis of Barretts Metaplasia from a normal epithelium are poorly understood. To investigate this, our study subjected a 3D model of the normal human oesophageal mucosa to repeated, pulsatile exposure to specific bile components and examined changes in gene expression. Initial 2D experiments with a range of bile salts observed that taurochenodeoxycholate (TCDC) impacted upon NF-kB activation without causing cell death. Informed by this, the 3D human oesophageal model was repeatedly exposed to TCDC in the presence and absence of acid, and the epithelial cells underwent gene expression profiling. We identified ~300 differentially expressed genes following each treatment, with a large and significant overlap between treatments. Enrichment analysis (Broad GSEA, DAVID and Metacore, GeneGo Inc) identified multiple gene sets related to cell signalling, inflammation, proliferation, differentiation and cell adhesion. Specifically NF-kB activation, Wnt signalling, cell adhesion and targets for the transcription factors PTF1A and HNF4 were highlighted. CDX1/2 transcription factors are believed to play a role in BM development; however, in this study their targets were not enriched, suggesting that CDX1/2 activation may not be the one of the initial events for BM formation. Our findings highlight new areas for investigation in the earliest stages of BM pathogenesis of oesophageal diseases and new potential therapeutic targets.
Pulsatile exposure to simulated reflux leads to changes in gene expression in a 3D model of oesophageal mucosa.
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View SamplesTranslation and mRNA decay are intimately connected processes, and translational inhibition often precedes and stimulates transcript degradation. Here, we have focused on methods that allow determination of mRNA stability on a transcriptome-wide scale. We describe experimental and computational methods for the two most commonly used approaches (transcriptional inhibition and metabolic labeling), and we discuss associated caveats. Overall design: Metabolic labeling time courses (1, 2, 4, 8, 12, 24 hr) using 4SU were performed in HEK293.
Determining mRNA half-lives on a transcriptome-wide scale.
Treatment, Subject
View SamplesDistinct shaping of the upper versus lower facial skeleton is essential for function of the vertebrate jaw and middle ear, yet the cellular mechanisms by which this occurs have remained unclear. Here, we show that Endothelin1 (Edn1) signaling accelerates mesenchymal condensation and subsequent cartilage formation in the lower face through antagonism of Jagged-Notch signaling and Prrx1 transcription factors. A genomic analysis of facial skeletal precursors in mutants and overexpression embryos reveals that Jagged-Notch signaling represses genes that are strongly induced as pharyngeal arch neural crest-derived cells begin skeletal differentiation. In wild types, initial Jagged-Notch repression dorsally ensures that barx1+ condensations and cartilage differentiation occur first in ventral-intermediate zones of the pharyngeal arches. Reduced Jagged-Notch signaling results in an expansion of pre-cartilage condensations in the upper face, with loss of barx1 partially restoring dorsal cartilage shapes in jag1b mutants. Further, by studying new mutants for zebrafish prrx1a and prrx1b, we find that Prrx1 genes function in parallel to Jagged-Notch signaling to restrict the formation of dorsal barx1+ pre-cartilage condensations. Consistently, combined losses of jag1b and prrx1a/b robustly rescue ventral barx1+ condensations and lower facial cartilage development in edn1 mutants. Together, our work suggests that Edn1 works through parallel inhibition of Jagged-Notch and Prrx1 pathways to promote an earlier and more extensive establishment of cartilage condensations in the lower face. Overall design: We performed RNAseq on FACS-sorted neural crest-derived pharyngeal arch cells (fli1a:GFP; sox10:DsRed double positive) from wild-type embryos at 3 different stages (20, 28, and 36 hours post fertilization) and embryos with altered levels of Edn1 and Notch signaling (edn1 mutants and hsp70I:Gal4; UAS:Edn1 transgenics; jag1b mutants, dibenzazepine-treated embryos, and hsp70I:Gal4; UAS:NICD transgenics. We also sequenced RNA from heat-shocked UAS:Edn1+ and hsp70I:Gal4+ transgenics and jag1b+/+ controls.
Competition between Jagged-Notch and Endothelin1 Signaling Selectively Restricts Cartilage Formation in the Zebrafish Upper Face.
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View SamplesKrppel-like factor 9 (Klf9), a zinc-finger transcription factor, is implicated in the control of cell proliferation, cell differentiation and cell fate in brain and uterus. Using Klf9 null mutant mice, we have investigated the involvement of Klf9 in small intestine crypt-villus cell renewal and lineage determination. We report the predominant expression of Klf9 gene in small intestine smooth muscle (muscularis externa). Jejunums null for Klf9 have shorter villi, reduced crypt stem/transit cell proliferation, and altered lineage determination as indicated by decreased and increased numbers of Goblet and Paneth cells, respectively. A stimulatory role for Klf9 in villus cell migration was demonstrated by BrdU labeling. Results suggest that Klf9 controls the elaboration, from small intestine smooth muscle, of molecular mediator(s) of crypt cell proliferation and lineage determination, and of villus cell migration.
Dysregulation of intestinal crypt cell proliferation and villus cell migration in mice lacking Kruppel-like factor 9.
No sample metadata fields
View SamplesInsulin resistance represents a hallmark during the development of type 2 diabetes mellitus (T2D) and in the pathogenesis of obesity-associated disturbances of glucose and lipid metabolism 1,2,3. MicroRNA (miR)-dependent posttranscriptional gene silencing has recently been recognized to control gene expression in disease development and progression including that of insulin-resistant T2D. MiRs, whose deregulation alters hepatic insulin sensitivity include miR-143, miR-181 and miR-103/107. Here we report that expression of miR-802 is increased in liver of two obese mouse models and of obese human subjects. Inducible transgenic overexpression of miR-802 in mice causes impaired glucose tolerance and attenuates insulin sensitivity, while reduction of miR-802 expression improves glucose tolerance and insulin action. We identify Hnf1b as a target of miR-802-dependent silencing and shRNA-mediated reduction of Hnf1b in liver causes glucose intolerance, impairs insulin signaling and promotes hepatic gluconeogenesis. In turn, hepatic overexpression of Hnf1b improves insulin sensitivity in db/db mice. Thus, the present study defines a critical role for deregulated expression of miR-802 in the development of obesity-associated impairment of glucose metabolism via targeting Hnf1b and assigns Hnf1b an unexpected role in the control of hepatic insulin sensitivity.
Obesity-induced overexpression of miR-802 impairs glucose metabolism through silencing of Hnf1b.
Sex, Specimen part
View SamplesThe objective of the study was identify hepatic genes with expression by deprivation of gut flora. Two models were used: model 1 (study 1443KR) examined germ-free Sprague Dawley and model 2 (1512KR) examined antibiotic treated Han Wistar rats.
Systemic gut microbial modulation of bile acid metabolism in host tissue compartments.
Specimen part, Treatment
View SamplesPrevious studies have reported that the tumour cells of nasopharyngeal carcinoma (NPC) exhibit both recurrent chromosome abnormalities and changes in the expression of numerous genes. However, it is not known to what extent changes in the copy number of individual genes are associated with the observed expression changes. To address this, a genome wide analysis of chromosome copy number and gene expression was performed in tumour cells micro-dissected from the same NPC biopsies. Significant gene expression changes were identified in tumour suppressor genes (TSGs) and in tumour-promoting genes (TPGs) but almost 60% of these can be either upregulated or downregulated in different types of cancer. This suggests that the simplistic classification of genes as TSGs or TPGs may not be entirely appropriate and that the concept of onco-suppressors may be more extensive than previously recognised. Several genomic regions showing frequent copy number gain or loss were identified. Whereas TSGs were significantly enriched within regions of frequent loss, no significant enrichment of TPGs was observed in regions of frequent gain. However, on a gene by gene basis little correlation was found between DNA copy number and alterations in gene expression except for loss of expression from homozygous deletions and a single highly amplified segment which showed enhanced gene expression.
A global view of the oncogenic landscape in nasopharyngeal carcinoma: an integrated analysis at the genetic and expression levels.
Disease, Disease stage
View SamplesMyeloid progenitors derived from antibiotic-treated mice have cell-intrinsic functional defects. In this microarray dataset, the transcriptomes of bone marrow myeloid progenitors from antibiotic-treated and control mice are compared.
Microbiota-dependent signals are required to sustain TLR-mediated immune responses.
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View SamplesAortic valve calcification is the most common form of valvular heart disease, but the mechanisms of calcific aortic valve disease (CAVD) are unknown. NOTCH1 mutations are associated with aortic valve malformations and adult-onset calcification in families with inherited disease. The Notch signaling pathway is critical for multiple cell differentiation processes, but its role in the development of CAVD is not well understood. The aim of this study was to investigate the molecular changes that occur with inhibition of Notch signaling in the aortic valve. Notch signaling pathway members are expressed in adult aortic valve cusps, and examination of diseased human aortic valves revealed decreased expression of NOTCH1 in areas of calcium deposition. To identify downstream mediators of Notch1, we examined gene expression changes that occur with chemical inhibition of Notch signaling in rat aortic valve interstitial cells (AVICs).
Inhibitory role of Notch1 in calcific aortic valve disease.
Specimen part
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