Oesophageal 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 SamplesMicroarray analysis has been applied to the cell proliferation in a human colonic cel line, Caco-2. We have shown previously that a moderate riboflavin depletion around weaning has a profound impact on the structure and function of the small intestine of the rat, which is not reversible following riboflavin repletion. In this study we have modelled riboflavin deficiency in a human cell line, shown irreversible loss of cell viability associated with impaired mitosis and identified candidate effectors of riboflavin depletion in the cell.
Riboflavin depletion impairs cell proliferation in adult human duodenum: identification of potential effectors.
Cell line
View SamplesBergmann glial cells of the vertebrate cerebellum play essential roles in the development and maintenance of cerebellar structure and function. During development, Bergmann glia provide structural support to the expanding cerebellar anlage and also serve as guides for migrating neurons (granule cells). As the cerebellum matures, Bergmann glia become important in dendritic arborization, synapse maintenance and synaptic function. The molecular mechanisms underlying these diverse and important functions of Bergmann glia remain largely unknown.
Identification of novel glial genes by single-cell transcriptional profiling of Bergmann glial cells from mouse cerebellum.
Specimen part
View SamplesTo identify the gene expression profile of enteric glia and assess the transcriptional similarity between enteric and extraenteric glia, we performed RNA sequencing analysis on PLP1-expressing cells in the mouse intestine. This analysis shows that enteric glia are transcriptionally unique and distinct from other cell types in the nervous system. Enteric glia express many genes characteristic of the myelinating glia, Schwann cells and oli- godendrocytes, although there is no evidence of myelination in the murine ENS. Overall design: Total RNA expression profiles of PLP1 expressing enteric glial cells (GFP+) and non-glial cells (GFP-negative) were obtained from the ileum and colon of juvenile PLP1-eGFP transgenic mice.
Enteric glia express proteolipid protein 1 and are a transcriptionally unique population of glia in the mammalian nervous system.
Specimen part, Cell line, Subject
View SamplesCTLA-4 is thought to inhibit effector T cells both intrinsically, by competing with CD28 for B7 ligands, and extrinsically, through the action of regulatory T cells. We studied in vivo responses of normal and CTLA-4-deficient antigen-specific murine effector CD4+ T cells. In order to do these studies in a physiological model of immunity to foreign antigen, we transferred small numbers of congenically marked RAG2-deficient 5C.C7 T cells with either a normal or knockout allele of CTLA-4 into normal syngeneic B10.A recipient mice. The T cells were then activated by immunization with MCC peptide and LPS. To look for transcriptional signatures of negative regulation of T cell responses by CTLA-4, we used microarray analysis to compare transcripts in wild type and CTLA-4 KO 5C.C7 T cells four days after immunization. This is the first instance in which differences are observed in extent of accumulation of wild type and CTLA-4 KO 5C.C7 T cells.
Cutting edge: CTLA-4 on effector T cells inhibits in trans.
Specimen part
View SamplesThe estrous cycles of Limousin heifers (n = 30) were synchronized by insertion of a controlled internal drug release (CIDR) device (1.94 g progesterone; Pfizer Animal Health) placed into the vagina for 8 days. A 0.5 mg intramuscular injection of a prostaglandin F2a (PG) analogue (PG, Estrumate, Shering-Plough Animal Health, Hertfordshire, UK) was administered 1 day before CIDR removal. Heifers were checked for standing estrus and only those exhibiting estrus (Day 0) were used. All animals were expected to come in heat between 48 and 72 hours after CIDR removal. Cervical tissues were collected at slaughter from heifers 12h after CIDR removal (Group 1: CIDR + 12 h, n = 6), 24h after CIDR removal (Group 2: CIDR + 24 h, n = 6), at the onset of estrus (Group 3: Estrus, n = 4), 12 h after the onset of estrus (Group 4: estrus + 12 h, n = 5), 48 h after the onset of estrus (Group 5: Estrus+48h, n = 4) and on day 7 after the onset of estrus (Group 6: Luteal phase, n = 5). Overall design: Cervical tissue from 30 animals taken at 6 timepoints in the peri-oestrus period. +12hrs post CIDR, Onset of Oestrus,+12hrs post Oestrus, +48hrs post Oestrus, Luteal phase
Molecular aspects of mucin biosynthesis and mucus formation in the bovine cervix during the periestrous period.
Subject, Time
View SamplesA LHX4 transgenic reporter line with high specificity for developing mouse cone photoreceptors was identified and used to purify early stage cone photoreceptors for profiling by single cell RNA sequencing. Overall design: Collection of FACS-sorted LHX4::GFP+ E14.5 early cones and LHX4::GFP- retinal cells for further analysis.
Identification of Genes With Enriched Expression in Early Developing Mouse Cone Photoreceptors.
Specimen part, Cell line, Subject
View SamplesOur studies provide direct evidence that O-glycosylation pathways play a role in the regulation of cell growth through apoptosis and proliferation pathways. Eight small molecular weight analogues of the GalNAc-alpha-1-O-serine/threonine structure based on 1-benzyl-2-acetamido-2- deoxy-alpha-O-D-galactopyranoside have been synthesised and tested in 5 human colorectal cancer cell lines. Three inhibitors, 1-benzyl-2-acetamido-2-deoxy-alpha-O-D-galactopyranoside and the corresponding 2-azido- and C-glycoside analogues, were screened in two colorectal cancer cell lines at 0.5mM and showed induction of apoptosis. Proliferation was down regulated in the same two cell lines with all three inhibitors, as detected by Ki67 staining and gene array. Treatment both cell lines with inhibitors led to changes in glycosylation detected with peanut lectin. The competitive action of the inhibitors resulted in the intracellular formation of 28 aryl-glycan products which were identified by MALDI and electrospray mass spectroscopy. The structures found map onto known O-glycosylation biosynthetic pathways and showed a differential pattern for each of the inhibitors in both cell lines. Gene array analysis of the glycogenes illustrated a pattern of glycosytransferases that matched the glycan structures found in glycoproteins and aryl-glycans formed in the PC/AA/C1/SB10C cells, however there was no action of the three inhibitors on glycogene transcript levels. The inhibitors act at both intermediary metabolic and genomic levels, resulting in altered protein glycosylation and arylglycan formation. These events may play a part in growth arrest.
O-glycan inhibitors generate aryl-glycans, induce apoptosis and lead to growth inhibition in colorectal cancer cell lines.
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View SamplesAnalysis of knockdown of SDHD with or without knockdown of CDKN1C or SLC22A18 at gene expression level.
Parent-of-origin tumourigenesis is mediated by an essential imprinted modifier in SDHD-linked paragangliomas: SLC22A18 and CDKN1C are candidate tumour modifiers.
Specimen part, Cell line
View SamplesCure rates for patients with acute myeloid leukemia (AML) remain low despite ever-increasing dose intensity of cytotoxic therapy. In an effort to identify novel approaches to AML therapy, we recently reported a new method of chemical screening based on the modulation of a gene expression signature of interest. We applied this approach to the discovery of AML-differentiation-promoting compounds. Among the compounds inducing neutrophilic differentiation was DAPH1 (4,5-dianilinophthalimide), previously reported to inhibit epidermal growth factor receptor (EGFR) kinase activity. Here we report that the Food and Drug Administration (FDA)-approved EGFR inhibitor gefitinib similarly promotes the differentiation of AML cell lines and primary patient-derived AML blasts in vitro. Gefitinib induced differentiation based on morphologic assessment, nitro-blue tetrazolium reduction, cell-surface markers, genome-wide patterns of gene expression, and inhibition of proliferation at clinically achievable doses. Importantly, EGFR expression was not detected in AML cells, indicating that gefitinib functions through a previously unrecognized EGFR-independent mechanism. These studies indicate that clinical trials testing the efficacy of gefitinib in patients with AML are warranted.
Gefitinib induces myeloid differentiation of acute myeloid leukemia.
Disease, Disease stage, Cell line
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