Project description:We isolated and selected intestinal adenoma organoids from Apc1638N/+ and Apc1638N/+; Kras mice. After the selection procedure, we maintained the cultures with or without TGF-beta for 18h. RNA was isolated to determine the effect of oncogenic Kras on the gene expression changes. Total RNA obtained from Apc1638N/+; Kras organoids were compared to Apc1638N/+ samples in the absence or presence of 3 ng/ml TGF-beta (18h).
Project description:Intestinal crypts isolated from Apcflox/flox; villin-CreERT mice were treated with Tamoxifen to induce the deletion of Apc. Tamoxifen-treated organoids were selected in the absence of Wnt agonists and then treated with TGF-beta. Total RNA obtained from Tamoxifen-treated, Apc-deleted intestinal organoids in the absence or presence of 3 ng/ml TGF-beta (18h).
Project description:We isolated and selected intestinal adenoma organoids from Lgr5-EGFP-IRES-CreER; Apcflox/flox mice and added tamoxifen to induce the deletion of the Apc gene in the intestinal stem cells. Gene expressions on day7 and day20 after the addition of tamoxifen were compared, representing two stages with different colorectal cancer stem cell content. Total RNA obtained from Lgr5-EGFP-IRES-CreER; Apcflox/flox organoids were compared 7 days and 20 days after the addition of tamoxifen, cultured without the Wnt-agonist R-Spondin1.
Project description:We isolated and selected intestinal adenoma organoids from villin-CreER; Apcflox/flox and villin-CreER; Apcflox/flox; Prox1flox/flox mice and added tamoxifen to induce the deletion of the Apc and Prox1 genes in the intestinal epitheliul ex vivo. Microarray experiments were carried out 7 days after the addition of tamoxifen. Total RNA obtained from villin-CreER; Apcflox/flox and villin-CreER; Apcflox/flox; Prox1flox/flox organoids were compared 7 days after the addition of tamoxifen and 5 days after the selection for Apc-mutant organoids in the absence of the Wnt-agonist R-Spondin1.
Project description:Pioneering studies within the last few years have allowed the in vitro expansion of tissue-specific adult stem cells from a variety of endoderm-derived organs, including the stomach, small intestine and colon. Here we derived organoids from mouse gallbladder tissue (gallbladder organoids), from mouse liver (including the extrahepatic biliary ducts and gallbladder; liver organoids) and from mouse small intestine tissue (intestinal organoids). RNA was prepared from these organoids and used to assay expression of 21,258 genes using Affymetrix gene expression arrays. RNA was also prepared from mouse gallbladder, liver and small intestine tissues and used to assay gene expression in these tissues. Finally, gallbladder organoids were induced to differentiate by removing R-spondin 1 and noggin from the culture media and subjected to gene expression array analysis. RNA was extracted from mouse gallbladder organoids, differentiated gallbladder organoids, liver organoids, small intestine organoids, gallbladder tissue, liver tissue and small intestine tissue and then used for hybridization of Affymetrix gene expression microarrays.
Project description:Murine small intestinal crypts of six independent mice were isolated and cultured as 3D-Organoids. Expression of NICD and loss of p53 mutagenesis was induced by 24h treatment with 4OH-tamoxifen in three of the cultures, resulting in three mutant organoid lines. The other three organoid lines were not exposed to tamoxifen and served as controls. Of each organoid line a duplicate was taken resulting in six control and six mutant samples that were compared in the analysis.
Project description:PeyerM-bM-^@M-^Ys Patches consist of domains of specialized intestinal epithelium overlying Gut-Associated Lymphoid Tissue (GALT). Luminal antigens reach the GALT by translocation through epithelial gatekeeper cells, so-called M cells. We have recently demonstrated that all epithelial cells required for the digestive functions of the intestine are generated from Lgr5-expressing stem cells. Here, we show that M cells also derive from these crypt-based Lgr5 stem cells. The Ets family transcription factor Spi-B, known to control effector functions of bone marrow-derived immune cells, is specifically expressed in M cells. In Spi-B-/- mice, M cells are entirely absent, which occurs in a cell-autonomous fashion. It has been shown that Tnfsf11 (RankL) can induce M cell development in vivo. In intestinal organoid (M-bM-^@M-^Xmini-gutM-bM-^@M-^Y) culture, we show that stimulation with RankL induces SpiB expression within 24hrs and subsequently of other M cell markers. We conclude that RankL-induced expression of Spi-B is essential for Lgr5 stem cell-derived epithelial precursors to develop into M cells. Small intestinal organoids were derived from wildtype (WT) mice. Recombinant mouse RankL (BioLegend) was added to the organoid culture medium in concentrations of 50-200ng/ml and fresh medium was added at day 2 and day 5. At the indicated time points, organoids were harvested for RNA isolation and microarray analysis to look for gene expression changes in reponse to RanKL.
Project description:In order to unravel the impact of intestinal smooth muscle tissue on the intestinal epithelium, we isolated clean smooth muscle, cultured it for 24h in DMEM-F12, and collected the supernatant (muscle-SN). This supernatant was used to treat small intestinal organoids (made of intestinal epithelium), compared to normal ENR treatment. After 5 days of muscle-SN exposure, we disrupted the organoids, and directly isolate the RNA. RNA-seq was performed in this sample to assess the genetic changes induced by muscle products.
Project description:Differentiation and specialisation of epithelial cells in the small intestine is regulated in two ways. First, there is differentiation along the crypt-villus axis of the intestinal stem cells into absorptive enterocytes, Paneth, goblet, tuft, enteroendocrine or M-cells, which is mainly regulated by WNT. Second, there is specialization along the cephalocaudal axis with different absorptive and digestive functions in duodenum, jejunum and ileum that is controlled by several transcription factors such as GATA4. However, so far it is unknown whether location-specific functional properties are intrinsically programmed within stem cells or if continuous signalling from mesenchymal cells is necessary to maintain the location-specific identity of the small intestine. By using the pure epithelial organoid technique, we show that region-specific gene expression profiles are conserved throughout long-term cultures of both mouse and human intestinal stem cells and correlated with differential Gata4 expression. Furthermore, the human organoid culture system demonstrates that Gata4-regulated gene expression is only allowed in absence of WNT signalling. These data show that location-specific function is intrinsically programmed in the adult stem cells of the small intestine and that their differentiation fate is independent of location-specific extracellular signals. In light of the potential future clinical application of small intestine-derived organoids, our data imply that it is important to generate GATA4-positive and GATA4-negative cultures to regenerate all essential functions of the small intestine. RNA sequencing of intestinal crypts, villi and cultured organoids derived from mouse duodenum, jejunum and ileum
Project description:The adult stem cell marker Lgr5 and its close relative Lgr4 are often co-expressed in Wnt-driven proliferative compartments. Conditional deletion of the two genes in the gut impairs expression of Wnt target genes and results in rapid demise of intestinal crypts, thus phenocopying the effects of Wnt pathway inhibition. By mass-spectrometry, we find that Lgr4 and Lgr5 associate with the endogenous Wnt co-receptors Frizzled-5/7 and Lrp5/6 in HEK293 cells and in colorectal cancer cells. We also find that soluble Rspondin1, a Wnt pathway agonist, specifically binds to endogenous Lgr4 on HEK293 cells. In these cells, soluble Rspondin1 potently enhances canonical Wnt signals initiated by Wnt3A. Removal of Lgr4 does not affect Wnt3A-induced signals, but abrogates the Rspondin1-mediated enhancement of these signals, a phenomenon rescued by re-expression of Lgr4, -5 or -6. Rspondin1 and can be rescued by Wnt pathway activation. Lgr4/5/6 are facultative Wnt receptor components that mediate Wnt signal enhancement by soluble Rspondin proteins. We used two different experimental setups to show that concomitant deletion of Lgr4 and Lgr5 affects the expression of Wnt pathway target genes. First, we determined the downregulated genes after Lgr4/5 deletion in AhCre_Lgr4fl/fl_Lgr5 fl/fl mice on day 1 post-deletion, before any histological changes are apparent in these mice (Lgr4/5 gene signature). Next, we acutely withheld the Wnt agonist Rspondin1 from in vitro crypt organoid cultures and performed differential gene expression before, and 1 day after withdrawal (Rspondin1 withdrawal signature). For better comparison we also deleted the Lgr4 and Lgr5 in vitro in organoids isolated from VillinCre_Lgr4fl/fl_Lgr5 fl/fl mice, and performed microarrays 1 day after deletion in vitro. Furthermore, we used published expression data from Apcfl/fl mice (Apc deletion signature). Deletion of Apc results in the immediate upregulation of Wnt pathway target genes. Comparison of the Lgr4/5 gene signature to both the Rspondin1 withdrawal signature and the Apc deletion signatures using Gene Set Enrichment Analysis (GSEA) showed that the genes deregulated after simultaneous deletion of Lgr4 and -5 are in the majority under the control of the Wnt pathway.