Notch1 deficient hair matrix keratinocytes have lower mitotic rates, resulting in smaller follicles with fewer cells. In addition, the ratio of melanocytes to keratinocytes is greatly reduced. Microarray was performed to study downstream mechanism of Notch1-deficiency
Bi-compartmental communication contributes to the opposite proliferative behavior of Notch1-deficient hair follicle and epidermal keratinocytes.
No sample metadata fields
View SamplesPro-inflammatory cytokines were shown to promote growth and survival of cancerous cells. TNF induced RelA:p50 NF-B dimer via the canonical pathway is thought to link inflammation with cancer. Integrating biochemical and computational studies we identify that deficiency of non-canonical signal transducer p100 triggers a positive autoregulatory loop, which instead perpetuates an alternate RelB:p50 containing NF-B activity upon TNF treatment. TNF stimulated RelB:p50 dimer is sufficient for mediating NF-B target gene-expressions and suppressing apoptotic cellular death independent of principal NF-B subunit RelA. We further demonstrate that activating mutations in non-canonical NF-B module deplete multiple myeloma cells of p100, thereby, provoking autoregulatory RelB:p50 activation. Finally, autoregulatory control reinforces protracted pro-survival NF-B response, albeit comprising of RelB:p50, upon TNF priming that protects myeloma cells with dysfunctional p100 from subsequent apoptotic insults. In sum, we present evidence for positive autoregulation mediated through the NF-B system and its potential involvement in human neoplasm.
Non-canonical NFκB mutations reinforce pro-survival TNF response in multiple myeloma through an autoregulatory RelB:p50 NFκB pathway.
Specimen part, Treatment
View SamplesLgr5+ adult intestinal stem cells are highly proliferative throughout life. Single Lgr5+ stem cells can be cultured into 3D epithelial organoids containing all cell types at nearnormal ratios. Culture conditions to generate the main cell types have been established previously, but signals inducing the various types of enteroendocrine cells (EECs) have remained elusive. Here we generate quiescent Lgr5+ stem cells in vitro by inhibition of the EGF-receptor (EGFR) and mitogen-associated protein kinase (MAPK) signaling pathways in organoids, a state that can be readily reversed. Quiescent Lgr5+ stem cells gain a distinct molecular signature, biased towards EEC differentiation. Indeed, combined inhibition of Wnt, Notch and MAPK pathways efficiently generates a diversity of EEC subtypes in vitro. Our observations uncouple Wnt-dependent stem cell maintenance from EGF-dependent proliferation and cell fate choice, and provide an in vitro approach for the study of the elusive EECs. Overall design: We established a stable culture of quiescent Lgr5+ intestinal stem cells in culture. These highly resemble quiescent secretory precursors, which has high EEC differentiation potential. Following on this lead, we elucidated what signals are required to generate EEC cells of all varieties, and provide a method to produce these EEC cells in large numbers.
Induced Quiescence of Lgr5+ Stem Cells in Intestinal Organoids Enables Differentiation of Hormone-Producing Enteroendocrine Cells.
Specimen part, Cell line, Subject
View SamplesUnderstanding the development and function of an organ requires the characterization of all of its cell types. Traditional methods for visualizing and isolating sub-populations of cells are based on mRNA or protein expression of only few known marker genes. The unequivocal identification of a specific marker gene, however, poses a major challenge, particularly if this cell type is rare. Identifying rare cell types, such as stem cells, short-lived progenitors, cancer stem cells, or circulating tumor cells is crucial to acquire a better understanding of normal or diseased tissue biology. To address this challenge we sequenced the transcriptome of hundreds of randomly selected cells from mouse intestinal organoids, cultured self-organizing epithelial structures that contain all cell lineages of the mammalian intestine. Organoid buds, like intestinal crypts, harbor stem cells that continuously differentiate into a variety of cell types, occurring at widely different abundances. Since available computational methods can only resolve more abundant cell types, we developed RaceID, an algorithm for rare cell type identification in complex populations of single cells. We demonstrate that this algorithm can resolve cell types represented by only a single cell in a population of randomly sampled organoid cells. We use this algorithm to identify Reg4 as a novel marker for enteroendocrine cells, a rare population of hormone producing intestinal cells. Next, we use Reg4 expression to enrich for these rare cells and investigate the heterogeneity within this population. Reassuringly, RaceID confirmed the existence of known enteroendocrine lineages, and moreover, discovered novel subtypes, which we subsequently validated in vivo. Having validated RaceID by this proof-of-principle experiment we then apply the algorithm to ex vivo isolated LGR5 positive cells and their direct progeny and demonstrate homogeneity of the stem cell pool. We envision broad applicability of our method for discovering rare cell types and the corresponding marker genes in healthy and diseased organs. Overall design: Small intestinal crypts were isolated from a single wild-type C57BL/6 mouse, a Reg4-dsRed-knock-in mouse and an Lgr5-GFP-DTR mouse. The crypts were propagated and expanded in culture as organoids. For each experiment, multiple organoids were harvested and dissociated into single cells. Each experiment was done twice, using different passage of the same organoid culture. We also included a pool-and-split control for 96 Reg4-dsRed positive intetsinal cells and a control library with 5 mouse embryonic stem cells (wells 1-5), 5 mouse embryonic fibroblasts (wells 6-10), 75 random organoid cells (wells 11-85), 5 wells without primer and without template (wells 86 and 93-96), and five wells with primer and without template (wells 87-92). We also sequenced two 96 well plates of Lgr5-EGFP positive single cells isolated ex vivo, and Lgr5 progeny collected after five days of lineage tracing. Label induction was performed using an Lgr5-Cre reporter mouse expressing YFP from Rosa26 promoter with a loxP flanked transcriptional road block in between. Five 96 well plates of YFP positive were sequenced. Sample number four also contains also unrelated samples (single cell barcode 49-96), which should be discarded.
Single-cell messenger RNA sequencing reveals rare intestinal cell types.
No sample metadata fields
View SamplesMammalian epidermal stem cells maintain homeostasis of skin epidermis and contribute to its regeneration throughout adult life. While two-dimensional mouse epidermal stem cell cultures have been established decades ago, a long-term, feeder cell- and serum-free culture system recapitulating murine epidermal architecture has not been available. Here we describe an epidermal organoid culture system that allows long-term, genetically stable expansion of adult epidermal stem cells. Our epidermal expansion media combines atypically high calcium concentrations, activation of cyclic AMP, FGF and R-spondin signaling with inhibition of BMP signaling. Organoids are established robustly from adult mouse skin and expand over at least 6 months, while maintaining the basal-apical organization of the mouse interfollicular epidermis. The system represents a powerful tool to study epidermal homeostasis and disease in vitro. Overall design: We establish an organoid culture system for long-term expansion of mouse epidermal stem cells. Using histological methods as well as low-coverage multiplexed RNA sequencing, we show that cultured organoids resembled interfollicular epidermis. We analyzed a total of 23 samples, including 6 controls that are isolated from the skin of mice. None-passaged as well as cultured organoids were compared with replicates. Differences growth factors and small molecules that allow expansion of organoids were compared with replicates.
Long-term expansion and differentiation of adult murine epidermal stem cells in 3D organoid cultures.
Cell line, Subject
View SamplesThe identification of Lgr5 as an intestinal stem cell marker has made it possible to isolate and study primary stem cells from small intestine. Using the cell cycle specific expression og the mKi67 gene, we generated a novel Ki67-RFP knock-in allele which identifies dividing cells. Using Lgr5-GFP;Ki67-RFP mice, we isolated CBCs with distinct Wnt signaling levels and cell cycle features, and analyzed their global gene expression pattern using microarrays. We concluded that the cycling Lgr5hi stem cells exit the cell cycle in transition into the secretory lineage. Lgr5med Ki67low intermediate precursors reside in the zone of differentiation, resemble quiescent stem cells and generate the Dll1+ secretory precursors and the label retaining cells. Our findings support the cycling stem cell hypothesis and highlight the heterogeneity of early progenitors during lineage commitment.
Mapping early fate determination in Lgr5+ crypt stem cells using a novel Ki67-RFP allele.
Specimen part
View SamplesAs a critical cellular stress sensor, p53 mediates a variety of defensive processes including cell-cycle arrest, apoptosis, and senescence to prevent propagation of hyperproliferative cells or cells with a damaged genome, hence the formation of neoplasia. Transactivation of downstream genes plays an important while sometimes controversial role in regulating these cellular processes. To evaluate the dependence on transcriptional activation in p53s activities, we generated genetically-modified mouse lines carrying mutations in the transactivation domains (TADs) of p53. These transactivatio-deficient mutants serve as unique reagents to probe the dependence on robust transactivation in p53-mediated cellular functions, as well as the underneath mechanisms. To identify genes differentially regulated by these p53 mutants, we performed gene expression profiling analysis on mouse embryonic fibroblast cells (MEFs) from these mice in the context of oncogenic Ras-induced premature cellular senescence.
Distinct p53 transcriptional programs dictate acute DNA-damage responses and tumor suppression.
Specimen part
View SamplesIt is currently accepted that the human brain has a limited neurogenic capacity and an impaired regenerative potential. We have previously shown the existence of CD271-expressing neural stem cells (NSCs) in the subventricular zone (SVZ) of Parkinson's disease (PD) patients, which proliferate and differentiate towards neurons and glial cells in vitro. To study the molecular profile of these NSCs in detail, we performed RNA sequencing and mass spectrometry on CD271+ NSCs isolated from human post-mortem SVZ and on homogenates of the SVZ. CD271+ cells were isolated through magnetic cell separation (MACS). We first compared the molecular profile of CD271+ NSCs to the SVZ homogenate from control donors to assess the CD271+ NSCs gene signature and finally made a comparison between controls and PD patients to establish a specific molecular profile of NSCs and the SVZ in PD. While our transcriptome analysis did not identify any differentially expressed genes in the SVZ between control and PD patients, our proteome analysis revealed several proteins that were differentially expressed in PD. Some of these proteins are involved in cytoskeletal organization and mitochondrial function. Transcriptome and proteome analyses of NSCs from PD revealed changes in the expression of genes and proteins involved in metabolism, transcriptional activity and cytoskeletal organization. Our results not only confirm pathological hallmarks of PD (e.g. impaired mitochondrial function), but also suggest that NSCs may transit into a primed-quiescent state, that is in an “alert” non-proliferative phase in PD. Overall design: From post-mortem human SVZ of control and Parkinson disease donors we isolated CD271+ NSCs and Cd11b+ microglia by MACS and the whole SVZ to generate RNA sequencing libraries using Celseq2 method. We aimed for low coverage sequencing (~2 million mapped to the coding regions) per sample to investigate the gross changes in the transcriptome. Libraries (rpi small primer) were sequenced in 3 runs, 2 on an Illumina NextSeq500 using 75-bp paired-end sequencing at the Utrecht Seuqencing center (USEQ) and the third on a HiSeq4000 using 150-bp paired-end sequencing at Genomescan. All the samples were mapped in a single run to an average depth of ~10 million reads per sample. Reads were mapped to the latest human coding transcriptome using bwa, normalized and analyzed using the standard DESEQ2 package.
Transcriptome and proteome profiling of neural stem cells from the human subventricular zone in Parkinson's disease.
Specimen part, Subject
View SamplesA specialized population of memory CD8+ T-cells resides in the epithelium of the respiratory tract to maintain protection against recurring infections. These cells express CD69 and the integrin 7 (CD103) and correspond to tissue resident memory T-cells (TRM) also described in intestine, liver and brain. A less well characterized population of CD103- CD8+ T-cells also resides in lungs and expresses markers characteristic of effector memory T-cells (TEM). We determined the transcriptional profiles of these memory CD8+ T-cell subsets retrieved from human lung resection samples and compared these with corresponding T-cell populations from peripheral blood of the same individuals. Our results demonstrate that each of the populations exhibits a distinct transcriptional identity. We found that the lung environment has a major impact on gene expression profiles. Thus, transcriptomes from CD103+ and CD103- subsets from lungs are much more resemblant to one another than to those from CD103+ or CD103- memory CD8+ T-cells from blood. TRM express specific sets of chemokine receptors, in accordance with their unique migratory properties. Furthermore, these cells constitutively express cytokine and cytotoxic genes for immediate effector function and chemokines to attract auxiliary immune cells. At the same time, multiple genes encoding inhibitory regulators are also expressed. This suggests that rapid ability to unleash effector functions is counterbalanced by programmed restraint, a combination that may be critical in the exposed but delicate tissue of the lung. Comprehensive sets of transcription factors were identified that characterize the memory CD8+ populations in the lungs. Prominent among these were components of the Notch pathway. Using mice genetically lacking expression of the NOTCH1 and NOTCH2 receptors in T-cells, we demonstrated that Notch controls both the number of lung TRM as well as the function of lung TEM. Our data illustrate the adaptation of lung resident T-cells to the requirements of the respiratory epithelial environment. Defining the molecular imprinting of these cells is important for rational vaccine design and may help to improve the properties of T-cells for adoptive cellular therapy.
Programs for the persistence, vigilance and control of human CD8<sup>+</sup> lung-resident memory T cells.
Specimen part, Subject
View SamplesProliferation of the self-renewing epithelium of the gastric corpus occurs almost exclusively in the isthmus of the glands, from where cells migrate bi-directionally towards pit and base. The isthmus is therefore generally viewed as the stem cell zone. We find that the stem cell marker Troy is expressed at the gland base by a small subpopulation of chief cells. By lineage tracing using a Troy-eGFP-ires-CreERT2 allele, single marked cells are shown to generate entirely labeled gastric units over periods of months. This phenomenon accelerates upon tissue damage. Troy+ chief cells can be cultured to generate long-lived gastric organoids. Troy marks a specific, 'plastic' subset of differentiated chief cells capable of replenishing entire gastric units, essentially serving as a quiescent reserve stem cell.
Differentiated Troy+ chief cells act as reserve stem cells to generate all lineages of the stomach epithelium.
Specimen part
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