Project description:A detailed understanding of intestinal stem cell (ISC) self-renewal and differentiation is required for better treatment options for a variety of chronic intestinal diseases, however, current models of ISC lineage hierarchy and segregation are still under debate. Here we report the identification of Lgr5+ ISCs that express Flattop (Fltp), a Wnt/planar cell polarity (PCP) reporter and effector gene. Functional analysis and lineage tracing revealed that Wnt/PCP-activated Fltp+ ISCs are primed towards either the enteroendocrine or Paneth cell lineage in vivo, while retaining self-renewal and multi-lineage capacity in vitro. Surprisingly, canonical Wnt/beta-catenin- and non-canonical Wnt/PCP-activated Lgr5+ ISCs are indistinguishable by the expression of stem-cell signature or secretory lineage-specifying genes, suggesting that lineage priming and cell-cycle exit is triggered at the post-transcriptional level by polarity cues and a switch of canonical to non-canonical Wnt signalling. Pseudotemporal ordering of targeted single-cell gene expression data allowed us to delineate the ISC differentiation path into enteroendocrine and Paneth cells. Strikingly, both lineages are directly recruited from ISCs via unipotent transition states, excluding the existence of formerly predicted bi- or multipotent secretory progenitors. Transitory cells that mature into Paneth cells are defined by label-retention and co-expression of stem cell and secretory lineage genes, indicating that these cells are the previously described Lgr5+ label-retaining cells (LRCs). Taken together, we identified the Wnt/PCP pathway as a new niche signal and polarity cue regulating stem cell fate. Active Wnt/PCP signalling represents one of the earliest events in ISC lineage priming towards the Paneth and enteroendocrine cell fate, preceding lateral inhibition and expression of secretory lineage-specifying genes. Thus, our findings provide a better understanding of the niche signals and redefine the mechanisms underlying ISC lineage hierarchy and segregation. Here we establish the Wnt/Planar cell polarity (PCP) gene Flattop (Fltp) as a unique marker for intestinal LRCs and their distinct secretory fate. We show that Fltp+ cells are characterized by a combined stem cell and secretory gene signature. A subset of Fltp+ cells is classified by label-retention and predominantly locates at position +4, indicative of quiescent stem cells. Strikingly, Fltp+ LRCs are specified by Wnt/PCP signaling in contrast to actively cycling stem cells that rely on the canonical Wnt/β-catenin pathway. In mice with disturbed Wnt/PCP signaling, the differentiation of enteroendocrine cells from LRCs is impaired. These findings establish Fltp as a novel marker for intestinal LRCs and implicate Wnt/PCP signaling in cell-cycle exit and commitment of ISCs to the secretory lineage. Taken together, we not only provide a marker to study LRCs in homeostatic and diseased conditions, but also identify the Wnt/PCP signaling pathway as a therapeutic target for colorectal cancer and metabolic disease.
Project description:We performed 7 single-cell RNAseq experiments to identify progenitor cell populations in the small intestine. To also capture rare intestinal cell populations such as stem cells and secretory cells we not only analyzed crypt cells from wildtype mice but also used two reporter mouse lines: i) the FltpZV/+ mouse line of which we mixed live crypt cells with Fltp Venus reporter (FVR) positive cells at different ratios and ii) Foxa2-Venus fusion (FVF) reporter mice. The FVF-enriched samples are part of another manuscript (link to GEO# will be provided). Using this FACS-based enrichment strategy, we could identify a Paneth cell-primed ISC population and potential progenitor populations for all intestinal lineages. To assess the role of Wnt/PCP signaling for enteroendocrine and Paneth cell differentiation, we performed 4 single-cell RNAseq experiments from crypt cells of Celsr1crsh/+; FltpZV/ZV compound mutant mice. When comparing control and mutant cells we found specific transcriptional alterations in the Paneth cell lineage.
Project description:Paneth cells are targets of allo-reactive T cells during acute graft-versus-host disease (GVHD). GVHD-related loss of Paneth cells is connected to intestinal dysbiosis and a decline of antimicrobial peptides. Glucagon-like-peptide-2 (GLP-2) is an enteroendocrine tissue hormone, produced by the intestinal L-cells, that leads to expansion of Paneth cells. Microarray-based analysis of the intestinal tract revealed upregulation of a host-defense gene signature, increased Reg3-γ and Defensin-α-4 in the teduglutide treated group compared to the vehicle treated group. these results indicate that treatment of GVHD mice the GLP-2 analogue, teduglutide, restores intestinal homeostasis with increased Paneth cells and antimicrobial peptides
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:We identify arachidonic acid (AA), as a direct proliferation promoter of intestinal epithelial cells, facilitating small intestinal regeneration. In the transcriptomes, it shows that AA treatment upregulated proliferation-related genes including Wnt signaling target genes, while downregulated differentiation-related genes including enterocyte, goblet cell, Paneth cell, enteroendocrine cell, and tuft cell markers. Additionally, AA could also upregulate stem cell-associated genes which have been highly expressed three days after 12Gy IR injury (e.g. Clu, Lamc2, Anxa1, Areg, and Ly6d). The study shows that AA treatment can be considered a potential therapy for irradiation injury repair and tissue regeneration.
Project description:Enterocytes and four classic secretory cell types derive from intestinal epithelial stem cells. Based on morphology, location, and canonical markers, goblet and Paneth cells are considered distinct secretory types. Here, we report high overlap in their transcripts and sites of accessible chromatin, in marked contrast to those of their enteroendocrine or tuft cell siblings. Mouse and human goblet and Paneth cells express extraordinary fractions of few antimicrobial genes, which reflect specific responses to local niches. Wnt signaling retains some ATOH1+ secretory cells in crypt bottoms, where absence of BMP signaling potently induces Paneth features. Cells that migrate away from crypt bottoms encounter BMPs and thereby acquire goblet properties. These phenotypes and underlying accessible cis-elements interconvert in post-mitotic cells. Thus, goblet and Paneth properties represent alternative phenotypic manifestations of a common signal-responsive terminal cell type. These findings reveal exquisite niche-dependent cell plasticity and cis-regulatory dynamics in likely response to antimicrobial needs
Project description:Enterocytes and four classic secretory cell types derive from intestinal epithelial stem cells. Based on morphology, location, and canonical markers, goblet and Paneth cells are considered distinct secretory types. Here, we report high overlap in their transcripts and sites of accessible chromatin, in marked contrast to those of their enteroendocrine or tuft cell siblings. Mouse and human goblet and Paneth cells express extraordinary fractions of few antimicrobial genes, which reflect specific responses to local niches. Wnt signaling retains some ATOH1+ secretory cells in crypt bottoms, where absence of BMP signaling potently induces Paneth features. Cells that migrate away from crypt bottoms encounter BMPs and thereby acquire goblet properties. These phenotypes and underlying accessible cis-elements interconvert in post-mitotic cells. Thus, goblet and Paneth properties represent alternative phenotypic manifestations of a common signal-responsive terminal cell type. These findings reveal exquisite niche-dependent cell plasticity and cis-regulatory dynamics in likely response to antimicrobial needs.