Project description:BACKGROUND & AIMS: Stems cells within the intestinal epithelium generate daughter cells which undergo lineage commitment and maturation through the concerted action of the Wnt and Notch signalling cascades. Both pathways, in turn, regulate transcription factor networks which further define differentiation towards either enterocytes or one of three secretory cell lineages (Paneth, goblet or enteroendocrine cells). In this manuscript, we identified the Ets domain transcription factor, Spdef, as a novel lineage maker of goblet and Paneth cells. METHODS: To address the function of Spdef in vivo, we inactivated the Spdef gene and analysed the intestinal phenotype using a range of histological techniques and DNA microarray profiling. RESULTS: In accordance with the expression data we found that loss of Spdef severely impaired the maturation of goblet and Paneth cells and conversely lead to an accumulation of immature secretory progenitors. Moreover, we provide evidence suggesting that Spdef positively and negatively regulates a specific subset of goblet and Paneth cell genes including Cryptdins, Mmp7, Ang4, Kallikreins, and Muc2. CONCLUSION: We propose a model whereby Spdef acts downstream of Math1 to promote terminal differentiation of a secretory progenitor pool towards Paneth and goblet cells. Keywords: expression profiling
Project description:Goblet cell numbers decrease within the conjunctival epithelium in drying and cicatrizing ocular surface diseases. Factors regulating goblet cell differentiation in conjunctival epithelium are unknown. Recent data indicate that the transcription factor SAM-pointed domain epithelial-specific transcription factor (Spdef) is essential for goblet cell differentiation in tracheobronchial and gastrointestinal epithelium of mice. Using Spdef -/- mice, we determined that Spdef is required for conjunctival goblet cell differentiation and that Spdef -/- mice, which lack conjunctival goblet cells, have significantly increased corneal surface fluorescein staining and tear volume, a phenotype consistent with dry eye. Microarray analysis of conjunctival epithelium in Spdef -/- mice identified 43 signficantly upregulated genes and 110 signficantly downregulated genes in the conjunctival epithelium of Spdef -/- mice compared to that of Spdef +/+ control mice (3 fold change, p<0.01). Downregulated genes of particular interested included goblet cell-specific genes (Muc5ac, Tff1, Gcnt3). Upregulated genes included epithelial cell differentiation/keratinization genes (Sprr2h, Tgm1) and pro-inflammatory genes (Il1-α, Il-1β, Tnf-α), all of which are upregulated in dry eye. Interestingly, four Wnt pathway genes were downregulated. Conjunctival epithelium of Spdef +/+ and Spdef -/- mice was collected by laser capture microdissection for RNA extraction and hybridization on Affymetrix microarrays to determine if gene expression patterns in the conjunctival epithelium of Spdef -/- mice is altered compared to that of Spdef +/+ mice.
Project description:Goblet cell numbers decrease within the conjunctival epithelium in drying and cicatrizing ocular surface diseases. Factors regulating goblet cell differentiation in conjunctival epithelium are unknown. Recent data indicate that the transcription factor SAM-pointed domain epithelial-specific transcription factor (Spdef) is essential for goblet cell differentiation in tracheobronchial and gastrointestinal epithelium of mice. Using Spdef -/- mice, we determined that Spdef is required for conjunctival goblet cell differentiation and that Spdef -/- mice, which lack conjunctival goblet cells, have significantly increased corneal surface fluorescein staining and tear volume, a phenotype consistent with dry eye. Microarray analysis of conjunctival epithelium in Spdef -/- mice identified 43 signficantly upregulated genes and 110 signficantly downregulated genes in the conjunctival epithelium of Spdef -/- mice compared to that of Spdef +/+ control mice (3 fold change, p<0.01). Downregulated genes of particular interested included goblet cell-specific genes (Muc5ac, Tff1, Gcnt3). Upregulated genes included epithelial cell differentiation/keratinization genes (Sprr2h, Tgm1) and pro-inflammatory genes (Il1-α, Il-1β, Tnf-α), all of which are upregulated in dry eye. Interestingly, four Wnt pathway genes were downregulated.
Project description:Upon tamoxifen induced recombination, Villin-CreERT2+ Lsd1fl/fl (icKO) mice develop an immature intestinal epithelium characterized by an incomplete differentiation of enterocytes and secretory lineages, reduced number of goblet cells and a complete loss of Paneth cells. The main goal of this experiment was to test whether maturation of intestinal epithelium affects microbiota establishment and development. In addition, this loss of differentiated cell types after Lsd1 recombination is gradual and dependent on renewal times of each specific cell type (i.e. enterocytes take less than a week to be fully replenished while Paneth cells cycle around every 4 weeks). Hence by collecting stool from the same mouse at different time points after tamoxifen induced recombination a relationship between loss of particular cell types and changes in bacterial populations can be established. In addition, we wanted to test whether maturation of intestinal epithelium affects microbiota establishment and development
Project description:Villin-Cre+ Lsd1fl/fl (cKO) mice display an immature intestinal epithelium characterized by an incomplete differentiation of enterocytes and secretory lineages, reduced number of goblet cells and a complete loss of Paneth cells. This experiment aims to elucidate the differences in stool microbial composition derived from WT (Villin-Cre- Lsd1fl/fl) and cKO mice both in adult (2-month-old) and neonatal (14 days postpartum P14) stages. Different timepoints are crucial to understand the role of intestinal maturation in microbiome composition since said maturation is dependent on time-dependent external cues happening at P14-21 (weaning and transition from milk to solid foods).
Project description:Spdef is a transcription factor involved in differentiation of goblet cells. Goblet cells from RedMUC298trTg and Spdef -/-RedMUC298trTg were sorted to analyse the differential gene expression in the absence of Spdef.
Project description:Mice with an intestinal epithelial specific knockout of LSD1 have changes in the intestinal epithelium including loss of Paneth and Goblet cells along with a general status of epithelial immaturity. To assess the influence of these epithelial specific changes on the mucosal immune system we performed a scRNAseq on CD45+ immune cells from the small intestine of mice with an epithelial specific LSD1 deletion (Villin-Cre+; Lsd1f/f) and wild type mice (Villin-Cre -; Lsd1f/f). To rule out a possible influence of the bacterial microbiome in the observed changes in CD45+ cell types we performed the same experiment in mice treated with antibiotics. These data allowed us to pinpoint changes in the cell populations of the mucosal immune system upon loss of LSD1 in the intestinal epithelium such as IgA producing cells and ILCs.
Project description:Chronic obstructive pulmonary disease (COPD) is the 3rd leading cause of death in the United States and is caused primarily by cigarette smoking. Increased numbers of mucus-producing secretory (“goblet”) cells defined as goblet cell metaplasia or hyperplasia (GCMH), contributes significantly to COPD pathophysiology. The objective of this study was to determine whether NOTCH signaling regulates goblet cell differentiation in response to cigarette smoke. To this end, primary human bronchial epithelial cells (HBECs) from nonsmokers and COPD smokers were differentiated in vitro on air-liquid interface and exposed to cigarette smoke extract (CSE) for 7 days. NOTCH signaling activity was modulated using (1) the NOTCH/γ-secretase inhibitor Dibenzazepine (DBZ), (2) lentiviral over-expression of the NOTCH3-intracellular domain (NICD3) or (3) NOTCH3-specific siRNA. Cell differentiation and response to CSE were evaluated by qPCR, Western blotting, immunostaining and RNA-Seq. Our data demonstrate that CSE exposure of nonsmoker airway epithelium induced goblet cell differentiation characteristic of GCMH. Treatment with DBZ suppressed CSE-dependent induction of goblet cell differentiation. Furthermore, CSE induced NOTCH3 activation, as revealed by increased NOTCH3 nuclear localization and elevated NICD3 protein levels. Over-expression of NICD3 increased expression of the goblet cell associated genes SPDEF and MUC5AC, whereas NOTCH3 knockdown suppressed CSE-mediated induction of SPDEF and MUC5AC. Finally, CSE exposure of COPD airway epithelium induced goblet cell differentiation in a NOTCH3-dependent manner. These results identify NOTCH3 activation as one of the important mechanisms by which cigarette smoke induces goblet cell differentiation, thus providing a potential strategy to control GCMH-related pathologies in smokers and patients with COPD.
Project description:The goal of the present study was to determine whether loss of the insulin receptor alters the molecular landscape of the intestinal mucosa, using intestinal-epithelial insulin receptor knockout (IE-irKO) mice and both genetic (IRfl/fl and Villin-cre) controls. Quantitative proteomic analysis by Liquid Chromatography Mass Spectrometry (LC-MS) was deployed on jejunal and colonic mucosa from mice fed a chow- or Western diet (WD). Jejunal mucosa from IE-irKO mice demonstrated alterations in all intestinal cell linages, Paneth, goblet, absorptive and enteroendocrine cells, whereas only goblet and absorptive cells were affected in the colon. There was also a significant effect of the WD on the gut proteome. A significant reduction was detected in Paneth cell proteins with anti-microbial activity, including lysozyme C-1, angiogenin-4, cryptdin-related sequence1C-3 and -2, a-defensin 17 and intelectin-1a. The key protein expressed by goblet cells, mucin-2, was also reduced in the IE-irKO mice. Proteins involved in lipid metabolism, including aldose reductase-related protein 1, 15-hydroxyprostaglandin dehydrogenase [NAD(+)], apolipoprotein A-II and pyruvate dehydrogenase kinase isozyme 4, were increased in the mucosa of WD-fed IE-irKO mice as compared to controls. In contrast, expression of the nutrient-responsive gut hormones, glucose-dependent insulinotropic polypeptide and neurotensin, was reduced in the jejunal mucosa of IE-irKO mice, and there was a reduction in proteins of the P-type ATPases and the solute carrier-transporter family in the colon of WD-fed IE-irKO mice. In conclusion, IE-irKO mice display a distinct molecular phenotype, suggesting a biological role of insulin and its receptor in determining differentiated cell-specificity in the intestinal epithelium.
Project description:To assess the role of LSD1 in mouse small intestinal epithelium, we isolated small intestinal crypts and villus from wild type (WT) (Villin-Cre -; Lsd1f/f) and intestinal-epithelial-specific knock-out (cKO) (Villin-Cre+; Lsd1f/f) mice. This experiment uses a new Cre strain with 100% deletion efficiency. RNA was directly isolated from intestinal crypt and villus, and this was used for RNAseq. Gene expression analysis of cKO derived crypt and villus provides a spatially restricted outlook on the maturation status of the intestinal epithelium in the villi and the absence of Paneth cells in the crypt.