MiRNAs have the potential to regulate cellular differentiation programs. However, miRNA-deficiency in primary hematopoietic stem cells (HSCs) results in HSC depletion in mice, leaving the question of whether miRNAs play a role in early-lineage decisions unanswered. To address this issue, we deleted Dicer1, which encodes an essential RNaseIII enzyme for miRNA biogenesis, in murine CCAAT/enhancer-binding protein alpha (C/EBPA)-positive myeloid-committed progenitors in vivo. In contrast to the results in HSCs, we found that miRNA depletion affected neither the number of myeloid progenitors nor the percentage of C/EBPA-positive progenitor cells. Analysis of gene-expression profiles from wild type and Dicer1-deficient granulocyte-macrophage progenitors (GMPs) revealed that 20 miRNA families were active in GMPs. Of the derepressed miRNA targets in Dicer1-null GMPs, 27% are normally exclusively expressed in HSCs or are specific for multi-potent progenitors and erythropoiesis, indicating an altered gene-expression landscape. Dicer1-deficient GMPs were defective in myeloid development in vitro and exhibited an increased replating capacity, indicating a regained self-renewal potential of these cells. In mice, Dicer1 deletion blocked monocytic differentiation, depleted macrophages and caused myeloid dysplasia with morphological features of Pelger-Hut anomaly. These results provide evidence for a miRNA-controlled switch for a cellular program of self-renewal and expansion towards myeloid differentiation in GMPs.
Dicer1 deletion in myeloid-committed progenitors causes neutrophil dysplasia and blocks macrophage/dendritic cell development in mice.
Specimen part
View SamplesWe present ScarTrace, a single-cell sequencing strategy that allows us to simultaneously quantify information on clonal history and cell type for thousands of single cells obtained from different organs from adult zebrafish. Using this approach we show that all blood cells types in the kidney marrow arise from a small set of multipotent embryonic. In contrast, we find that cells in the eyes, brain, and caudal tail fin arise from many embryonic progenitors, which are more restricted and produce specific cell types in the adult tissue. Next we use ScarTrace to explore when embryonic cells commit to forming either left or right organs using the eyes and brain as a model system. Lastly we monitor regeneration of the caudal tail fin and identify a subpopulation of resident macrophages that have a clonal origin that is distinct from other blood cell types. Overall design: Single cell sequencing data from cells isolated from zebrafish organs (whole kidney marrow, forebrain, hindbrain, left eye, right eye, left midbrain, right midbrain, and regenerated fin). For each cell, we provide libraries with transcritpome and with clonal information, respectively.
Whole-organism clone tracing using single-cell sequencing.
Specimen part, Subject
View SamplesTo identify cellular and genetic abnormalities involved in interstrand cross link repair-deficient bone marrow failure and its transformation to leukemia, we used an Ercc1 hypomorphic mouse model (Ercc1 -/d).
ICL-induced miR139-3p and miR199a-3p have opposite roles in hematopoietic cell expansion and leukemic transformation.
Age, Specimen part
View SamplesExpression levels of the RNA-binding protein Quaking (QKI) are low in monocytes of early, human atherosclerotic lesions, but abundant in macrophages of advanced plaques. Specific depletion of QKI protein impaired monocyte adhesion, migration, differentiation into macrophages, and foam cell formation in vitro and in vivo. RNA-seq and microarray analysis of human monocyte and macrophage transcriptomes, including those of a unique QKI haploinsufficient patient, revealed striking changes in QKI-dependent mRNA levels and splicing of RNA transcripts. Overall design: RNA-seq analysis of primary monocytes and macrophages from a QKI haploinsufficient patient and their (control) sibling.
Quaking promotes monocyte differentiation into pro-atherogenic macrophages by controlling pre-mRNA splicing and gene expression.
No sample metadata fields
View SamplesIntroduction: In the recently completed Dutch GLUCOLD study, treatment of COPD patients with fluticasone salmeterol reduced the rate of decline in FEV1. These results indicate that ICS can have therapeutic efficacy in COPD. Aim: To explore the molecular mechanisms by which ICS exert their effects, we performed genome-wide gene expression profiling on bronchial biopsies from COPD patients who participated in the GLUCOLD study. Methods: An Affymetrix Human Gene Array ST version 1.0 was performed in a total of 221 bronchial biopsies that were available from 90 COPD patients at baseline and after 6 and 30 months of therapy. Linear mixed effects modeling was used to analyze treatment-specific changes in gene expression. A validation set was included and pathway analysis was performed with Gene Set Enrichment Analysis (GSEA). Results: The expression of 138 genes significantly decreased after both 6 and 30 months of treatment with fluticasone salmeterol versus placebo, whereas the expression of 140 genes increased. A more pronounced treatment-induced change in expression of 51 of these 278 genes was associated with a slower rate of decline in FEV1. Genes that decreased with treatment were involved in pathways related to cell cycle, oxidative phosphorylation, epithelial cell signaling, p53 signaling and T cell signaling. Genes that increased with treatment were involved in pathways related to focal adhesion, gap junction and extracellular matrix deposition. Conclusion: The present study suggests that gene expression in biological pathways of COPD is dynamic with treatment and reflects disease activity. This study opens the gate to targeted and phenotype-driven therapy of COPD.
Airway gene expression in COPD is dynamic with inhaled corticosteroid treatment and reflects biological pathways associated with disease activity.
Age
View SamplesNatural killer T (NKT) cells identified by CD1d-tetramer and TCRb were isolated from the thymi of wild type and Ezh2 knockout mice. The NKT cells were FACS sorted into different stages based on the surface expression of CD44 and NK1.1. Overall design: For both wildtype and knockout mice, RNA was extracted from two biological replicates of CD44+ NK1.1- cells, one replicate of CD44+ NK1.1+ cells and one replicate of CD44- NK1.1- cells. Each RNA sample was divided into four and sequenced on four lanes of an Illumina HiSeq sequencer.
A non-canonical function of Ezh2 preserves immune homeostasis.
Specimen part, Subject
View SamplesBACKGROUND: We have previously reported gene expression changes in the bronchial airway epithelium of active chronic smokers. In this study, we investigate the effects of Acute Smoke Exposure (ASE) from cigarettes on airway epithelial gene expression. METHODS: Bronchial airway epithelial cell brushings were collected via fiberoptic bronchoscopy from 63 individuals without recent exposure to cigarette smoke (> 2 days), at baseline and at 24 hours after smoking three cigarettes. RNA from these samples was profiled on Affymetrix Human Gene 1.0 ST microarrays. Differential gene expression was assessed using linear modeling and compared to previous smoking-related gene-expression signatures using Gene Set Enrichment Analysis (GSEA). RESULTS: We identified 91 genes differentially expressed 24-hours after exposure to three cigarettes (FDR < 0.25). ASE induces genes involved in xenobiotic metabolism, oxidative stress, and inflammation; and represses genes involved in cilium morphogenesis, and cell cycle. Genes induced by in vivo ASE are concordantly altered by ASE in vitro. While many genes altered by ASE are altered similarly in the airway of chronic smokers, metallothionein genes were induced by ASE and suppressed among chronic smokers. Metallothioneins were also suppressed in the bronchial airway of current and former chronic smokers with lung cancer relative to those with benign disease. CONCLUSIONS: Acute exposure to as little as three cigarettes alters gene-expression in bronchial airway epithelium in a manner that largely resembles the changes seen in chronic active smokers. The difference in the short-term and long-term effects of smoking on metallothionein expression and its relationship to lung cancer requires further study given these enzymes role in responding to oxidative stress.
Impact of acute exposure to cigarette smoke on airway gene expression.
Sex
View SamplesThe early life microbiome plays important roles in host immunological and metabolic development. Because type 1 diabetes (T1D) incidence has been increasing substantially in recent decades, we hypothesized that early-life antibiotic use alters gut microbiota that predisposes to disease. Using NOD mice that are genetically susceptible to T1D, we examined the effects of exposure to either continuous low-dose antibiotics or pulsed therapeutic antibiotics (PAT) early in life, mimicking childhood exposures. We found that in mice receiving PAT, T1D incidence was significantly higher, microbial community composition and structure differed compared with controls. In pre-diabetic male PAT mice, the intestinal lamina propria had lower Th17 and T reg proportions and intestinal SAA expression than in controls, suggesting key roles in transducing the altered microbiota signals. PAT affected microbial lipid metabolism and host cholesterol biosynthetic gene expression. These findings show that early-life antibiotic treatments alter the gut microbiota and its metabolic capacities, intestinal gene expression, and T-cell populations, accelerating T1D onset in NOD mice.
Antibiotic-mediated gut microbiome perturbation accelerates development of type 1 diabetes in mice.
Sex, Specimen part, Disease, Disease stage, Treatment
View SamplesAngiopoietin-like protein 4 (ANGPTL4, also referred to as Fiaf) has been proposed as circulating mediator between the gut microbiota and fat storage in adipose tissue. Very little is known about mechanisms of regulation of ANGPTL4 in the colon. Here we show that transcription and subsequent secretion of ANGPTL4 in human T84 and HT-29 colonocytes is highly induced by physiological concentrations of products of bacterial fermentation, the short chain fatty acids (SCFA). Induction of ANGPTL4 by SCFA cannot be mimicked by the histone deacetylase inhibitor Trichostatin A. SCFA induce ANGPTL4 by activating the nuclear receptor PPAR, as shown by use of PPAR antagonist, PPAR knock-down, and transactivation assay, which shows activation of PPAR but not PPAR and PPAR. At concentrations required for PPAR activation and ANGPTL4 induction in colonocytes, SCFA do not stimulate PPAR in mouse 3T3-L1 and human SGBS adipocytes, suggesting that SCFA act as selective PPAR modulators (SPPARM), which is supported by coactivator peptide recruitment assay and structural modelling. Consistent with the notion that fermentation leads to PPAR activation in vivo, feeding mice a diet rich in inulin was associated with induction of PPAR target genes and pathways in the colon, as shown by microarray and subsequent gene set enrichment analysis. It can be concluded that 1) SCFA potently stimulate ANGPTL4 synthesis in human colonocytes; 2) SCFA transactivate and bind to PPAR by serving as selective PPAR modulators. Our data point to activation of PPAR as a novel mechanism of gene regulation by SCFA in the colon.
Short-chain fatty acids stimulate angiopoietin-like 4 synthesis in human colon adenocarcinoma cells by activating peroxisome proliferator-activated receptor γ.
Sex, Age, Specimen part
View SamplesAngiopoietin-like protein 4 (ANGPTL4, also referred to as Fiaf) has been proposed as a circulating mediator between the gut microbiota and fat storage in adipose tissue. Very little is known about the mechanisms of regulation of ANGPTL4 in the colon. Here we show that transcription and subsequent secretion of ANGPTL4 in human T84 and HT-29 colonocytes is highly induced by physiological concentrations of products of bacterial fermentation, the short-chain fatty acids. Short-chain fatty acids induce ANGPTL4 by activating the nuclear receptor PPAR, as shown by microarray, transactivation assays, coactivator peptide recruitment assay, and use of PPAR antagonist. At concentrations required for PPAR activation and ANGPTL4 induction in colonocytes, SCFA do not stimulate PPAR in mouse 3T3-L1 and human SGBS adipocytes, suggesting that SCFA act as selective PPAR modulators (SPPARM), which is supported by coactivator peptide recruitment assay and structural modelling. It can be concluded that 1) SCFA potently stimulate ANGPTL4 synthesis in human colonocytes, and 2) SCFA transactivate and bind to PPAR by serving as selective PPAR modulators. Our data point to activation of PPAR as a novel mechanism of gene regulation by SCFA in the colon.
Short-chain fatty acids stimulate angiopoietin-like 4 synthesis in human colon adenocarcinoma cells by activating peroxisome proliferator-activated receptor γ.
Specimen part, Cell line, Treatment
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