The intestinal epithelium is continuously renewed by a pool of intestinal stem cells expressing Lgr5. We show that deletion of the key autophagy gene Atg7 affects the survival of Lgr5+ intestinal stem cells. Mechanistically, this involves defective DNA repair, oxidative stress, and altered interactions with the microbiota. This study highlights the importance of autophagy in maintaining the integrity of intestinal stem cells.
Essential role for autophagy protein ATG7 in the maintenance of intestinal stem cell integrity.
Specimen part
View SamplesThe corneal endothelium plays a primary role in maintaining corneal homeostasis and clarity, and must be surgically replaced with allogenic donor corneal endothelium in the event of visually significant dysfunction. However, a worldwide shortage of donor corneal tissue has led to a search for alternative sources of transplantable tissue. Cultured human corneal endothelial cells (HCEnC) have been shown to restore corneal clarity in experimental models of corneal endothelial dysfunction in animal models, but characterization of cultured HCEnC remains incomplete. To this end, we utilized next-generation RNA sequencing technology to compare the transcriptomic profile of ex vivo human corneal endothelium (evHCEnC) with that of primary HCEnC and HCEnC lines, and to determine the utility of cultured and immortalized corneal endothelial cells as models of in vivo corneal endothelium. Multidimensional analyses of the transcriptome datasets demonstrated that primary HCEnC have a closer relationship to evHCEnC than do immortalized HCEnC. Subsequent analyses showed that the majority of the genes specifically expressed in HCEnC (not expressed in ex vivo corneal epithelium or fibroblasts) demonstrated a marked variability of expression in cultured cells compared with evHCEnC. In addition, genes associated with either corneal endothelial cell function or corneal endothelial dystrophies were investigated. Significant differences in gene expression and protein levels were observed in the cultured cells compared with evHCEnC for each of the genes tested except for AGBL1 and LOXHD1, which were not detected by RNA-seq or qPCR. Our transcriptomic analysis suggests that at a molecular level primary HCEnC most closely resemble evHCEC and thus represent a viable therapeutic option for managing corneal endothelial dysfunction. Our findings also suggest that investigators should perform an assessment of the entire transcriptome of cultured HCEnC prior to determination of the potential clinical utility of the cultured HCEnC for the management of corneal endothelial cell failure. Overall design: Transcriptomes from ex vivo corneal endothelium, primary cultures and three cell lines were compared. Three samples of each endothelial cell group were submitted for RNA sequencing for a total of 15 samples. The transcriptome for the ex vivo corneal endothelium was used as the reference (i.e., proxy for in vivo corneal endothelium). Transcript abundances for a subset of genes associated with corneal endothelial cell function or disease were validated with qPCR and western blot. Samples of ex vivo endothelium used for validation were independent replicates not used for RNA-sequencing.
Transcriptomic Analysis of Cultured Corneal Endothelial Cells as a Validation for Their Use in Cell Replacement Therapy.
No sample metadata fields
View SamplesDefining the normal and age-dependent HCEnC transcriptome will further refine our understanding of the functional roles that the endothelium plays in the cornea and will provide a basis upon which to compare transcriptomes of normal and dystrophic endothelium for the subsequent development of gene-targeted therapies.
Transcriptome analysis of the human corneal endothelium.
Specimen part
View SamplesAnalysis of the transcriptome of mononuclear side population (SP) and main population (MP) cells of human fetal skeletal muscle from 12 human subjects of gestational age 14-18 weeks.
Regulation of myogenic progenitor proliferation in human fetal skeletal muscle by BMP4 and its antagonist Gremlin.
Specimen part
View SamplesFunctional analysis of ABCB5 in A375 and G3361 melanoma cells, by comparing stably-transfected controls to ABCB5-shRNA-targeted cells.
ABCB5 maintains melanoma-initiating cells through a proinflammatory cytokine signaling circuit.
Specimen part, Cell line
View SamplesTo find BMAL1-regulated genes in mice pituitary gland we performed a differential microarray from wild-type vs Bmal1-/- knock-out mice
Chromatin remodeling as a mechanism for circadian prolactin transcription: rhythmic NONO and SFPQ recruitment to HLTF.
Sex, Specimen part
View SamplesGlucocorticoids remain the most widely used class of anti-inflammatory and immunosuppressive agents. They act primarily by binding to the glucocorticoid receptor, resulting in direct and indirect effects on gene expression. The current understanding of glucocorticoid effects on transcription in human cells is based mostly on studies of cancer cell lines, immortalized cell lines, or highly mixed populations of primary cells (such as peripheral blood mononuclear cells). To advance the understanding of the transcriptome-wide effects of glucocorticoids on highly pure populations of primary human cells, we performed RNA-seq on nine such cell populations at two time points after in vitro exposure to methylprednisolone or vehicle. Overall design: Nine cell types were studied: four hematopoietic (circulating B cells, CD4+ T cells, monocytes, and neutrophils) and five non-hematopoietic (endothelial cells, fibroblasts, myoblasts, osteoblasts, and preadipocytes). Each cell type was obtained from a separate cohort of 4 unrelated healthy human donors (4 biological replicates per cell type: BR1 - BR4). Cells form each donor were independently cultured and exposed in vitro to glucocorticoid or vehicle. Non-hematopoietic cells were incubated until the early plateau phase of growth, then exposed to methylprednisolone or vehicle. Hematopoietic cells were collected from peripheral blood, purified by magnetic selection (negative selection for B cells, CD4+ T cells and neutrophils; positive selection for monocytes). Purified B cells, CD4+ T cells, and monocytes were incubated overnight, then exposed to methylprednisolone or vehicle. Purified neutrophils were cultured for 4 hours, then exposed to methylprednisolone or vehicle. Ethanol was used as a vehicle for methylprednisolone. Estimated final concentrations were 8500 mcg/L (22.7 mcM) for methylprednisolone and 0.07% (15.57 mM) for ethanol (vehicle). For each cell type, samples were collected at two time points after treatment with methylprednisolone or vehicle: 2 hours and 6 hours. Samples were collected into TRIzol reagent and frozen at -80°C prior to RNA extraction. RNA-seq data for all samples is made available in this GEO Series.
Immune regulation by glucocorticoids can be linked to cell type-dependent transcriptional responses.
Specimen part, Subject, Time
View SamplesBackground and Purpose
Upregulated signaling pathways in ruptured human saccular intracranial aneurysm wall: an emerging regulative role of Toll-like receptor signaling and nuclear factor-κB, hypoxia-inducible factor-1A, and ETS transcription factors.
No sample metadata fields
View SamplesMelanoma growth is driven by malignant melanoma initiating cells (MMIC) identified by expression of the ATP-binding cassette (ABC) member, ABCB5. ABCB5+ melanoma subpopulations have been shown to overexpress the vasculogenic differentiation markers CD144 (VE-cadherin) and TIE-1 and are associated with CD31-negative vasculogenic mimicry (VM), an established biomarker associated with increased patient mortality. Here we identify a critical role for VEGFR-1 signaling in ABCB5+ MMIC-dependent VM and tumor growth. Global gene expression analyses, validated by mRNA and protein determinations, revealed preferential expression of VEGFR-1 on ABCB5+ tumor cells purified from clinical melanomas and established melanoma lines. In vitro, VEGF induced in a VEGFR-1-dependent manner expression of CD144 in ABCB5+ subpopulations that constitutively expressed VEGFR-1, but not in ABCB5- bulk populations that were predominantly VEGFR-1-negative. In vivo, melanomaspecific shRNA-mediated knockdown of VEGFR-1 blocked the development of ABCB5+ VM morphology and inhibited ABCB5+ VM-associated production of the secreted melanoma mitogen, laminin. Moreover, melanoma-specific VEGFR-1 knockdown markedly inhibited tumor growth (by >90%). Our results demonstrate that VEGFR-1 function in MMIC regulates VM and associated laminin production, and show that this function represents one mechanism through which MMIC promote tumor growth.
VEGFR-1 expressed by malignant melanoma-initiating cells is required for tumor growth.
Specimen part
View SamplesCholestasis may cause cholemic nephropathy that can be modelled in common bile duct ligated (CBDL) mice. We aimed to explore the therapeutic efficacy and mechanisms of norursodeoxycholic acid (norUDCA) in cholemic nephropathy. To determine whether norUrsodeoxycholic acid (norUDCA) prevents cholemic nephropathy in long-term CBDL mice, a norUDCA-enriched diet (0.125% w/v, corresponding to 200 mg/kg/day for a mouse of 25 g body weight eating about 4g daily) or a standard mouse diet (Sniff, Soest, Germany) were started 5 days prior to CBDL and were continued until harvesting 3 weeks thereafter. For transcriptional profiling using microarray technology, we compared sham-operated (SOP) mice and 3-week CBDL mice that were either fed 0.125% norUDCA-enriched or standard mouse diets.
NorUrsodeoxycholic acid ameliorates cholemic nephropathy in bile duct ligated mice.
Specimen part
View Samples