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Sample records for intestinal cell kinase

  1. Diacylglycerol kinase regulation of protein kinase D during oxidative stress-induced intestinal cell injury

    International Nuclear Information System (INIS)

    Song Jun; Li Jing; Mourot, Joshua M.; Mark Evers, B.; Chung, Dai H.

    2008-01-01

    We recently demonstrated that protein kinase D (PKD) exerts a protective function during oxidative stress-induced intestinal epithelial cell injury; however, the exact role of DAG kinase (DGK)ζ, an isoform expressed in intestine, during this process is unknown. We sought to determine the role of DGK during oxidative stress-induced intestinal cell injury and whether DGK acts as an upstream regulator of PKD. Inhibition of DGK with R59022 compound or DGKζ siRNA transfection decreased H 2 O 2 -induced RIE-1 cell apoptosis as measured by DNA fragmentation and increased PKD phosphorylation. Overexpression of kinase-dead DGKζ also significantly increased PKD phosphorylation. Additionally, endogenous nuclear DGKζ rapidly translocated to the cytoplasm following H 2 O 2 treatment. Our findings demonstrate that DGK is involved in the regulation of oxidative stress-induced intestinal cell injury. PKD activation is induced by DGKζ, suggesting DGK is an upstream regulator of oxidative stress-induced activation of the PKD signaling pathway in intestinal epithelial cells

  2. Cyclin-dependent kinases regulate apoptosis of intestinal epithelial cells

    Science.gov (United States)

    Bhattacharya, Sujoy; Ray, Ramesh M.; Johnson, Leonard R.

    2014-01-01

    Homeostasis of the gastrointestinal epithelium is dependent upon a balance between cell proliferation and apoptosis. Cyclin-dependent kinases (Cdks) are well known for their role in cell proliferation. Previous studies from our group have shown that polyamine-depletion of intestinal epithelial cells (IEC-6) decreases cyclin-dependent kinase 2 (Cdk2) activity, increases p53 and p21Cip1 protein levels, induces G1 arrest, and protects cells from camptothecin (CPT)-induced apoptosis. Although emerging evidence suggests that members of the Cdk family are involved in the regulation of apoptosis, their roles directing apoptosis of IEC-6 cells are not known. In this study, we report that inhibition of Cdk1, 2, and 9 (with the broad range Cdk inhibitor, AZD5438) in proliferating IEC-6 cells triggered DNA damage, activated p53 signaling, inhibited proliferation, and induced apoptosis. By contrast, inhibition of Cdk2 (with NU6140) increased p53 protein and activity, inhibited proliferation, but had no effect on apoptosis. Notably, AZD5438 sensitized, whereas, NU6140 rescued proliferating IEC-6 cells from CPT-induced apoptosis. However, in colon carcinoma (Caco2) cells with mutant p53, treatment with either AZD5438 or NU6140 blocked proliferation, albeit more robustly with AZD5438. Both Cdk inhibitors induced apoptosis in Caco2 cells in a p53-independent manner. In serum starved quiescent IEC-6 cells, both AZD5438 and NU6140 decreased TNF- /CPT-induced activation of p53 and, consequently, rescued cells from apoptosis, indicating that sustained Cdk activity is required for apoptosis of quiescent cells. Furthermore, AZD5438 partially reversed the protective effect of polyamine depletion whereas NU6140 had no effect. Together, these results demonstrate that Cdks possess opposing roles in the control of apoptosis in quiescent and proliferating cells. In addition, Cdk inhibitors uncouple proliferation from apoptosis in a p53-dependent manner. PMID:24242917

  3. Intestinal Epithelial Cell Tyrosine Kinase 2 Transduces IL-22 Signals To Protect from Acute Colitis.

    Science.gov (United States)

    Hainzl, Eva; Stockinger, Silvia; Rauch, Isabella; Heider, Susanne; Berry, David; Lassnig, Caroline; Schwab, Clarissa; Rosebrock, Felix; Milinovich, Gabriel; Schlederer, Michaela; Wagner, Michael; Schleper, Christa; Loy, Alexander; Urich, Tim; Kenner, Lukas; Han, Xiaonan; Decker, Thomas; Strobl, Birgit; Müller, Mathias

    2015-11-15

    In the intestinal tract, IL-22 activates STAT3 to promote intestinal epithelial cell (IEC) homeostasis and tissue healing. The mechanism has remained obscure, but we demonstrate that IL-22 acts via tyrosine kinase 2 (Tyk2), a member of the Jak family. Using a mouse model for colitis, we show that Tyk2 deficiency is associated with an altered composition of the gut microbiota and exacerbates inflammatory bowel disease. Colitic Tyk2(-/-) mice have less p-STAT3 in colon tissue and their IECs proliferate less efficiently. Tyk2-deficient primary IECs show reduced p-STAT3 in response to IL-22 stimulation, and expression of IL-22-STAT3 target genes is reduced in IECs from healthy and colitic Tyk2(-/-) mice. Experiments with conditional Tyk2(-/-) mice reveal that IEC-specific depletion of Tyk2 aggravates colitis. Disease symptoms can be alleviated by administering high doses of rIL-22-Fc, indicating that Tyk2 deficiency can be rescued via the IL-22 receptor complex. The pivotal function of Tyk2 in IL-22-dependent colitis was confirmed in Citrobacter rodentium-induced disease. Thus, Tyk2 protects against acute colitis in part by amplifying inflammation-induced epithelial IL-22 signaling to STAT3. Copyright © 2015 by The American Association of Immunologists, Inc.

  4. Casein kinase 1-epsilon or 1-delta required for Wnt-mediated intestinal stem cell maintenance.

    Science.gov (United States)

    Morgenstern, Yael; Das Adhikari, Upasana; Ayyash, Muneef; Elyada, Ela; Tóth, Beáta; Moor, Andreas; Itzkovitz, Shalev; Ben-Neriah, Yinon

    2017-10-16

    The intestinal epithelium holds an immense regenerative capacity mobilized by intestinal stem cells (ISCs), much of it supported by Wnt pathway activation. Several unique regulatory mechanisms ensuring optimal levels of Wnt signaling have been recognized in ISCs. Here, we identify another Wnt signaling amplifier, CKIε, which is specifically upregulated in ISCs and is essential for ISC maintenance, especially in the absence of its close isoform CKIδ. Co-ablation of CKIδ/ε in the mouse gut epithelium results in rapid ISC elimination, with subsequent growth arrest, crypt-villous shrinking, and rapid mouse death. Unexpectedly, Wnt activation is preserved in all CKIδ/ε-deficient enterocyte populations, with the exception of Lgr5 + ISCs, which exhibit Dvl2-dependent Wnt signaling attenuation. CKIδ/ε-depleted gut organoids cease proliferating and die rapidly, yet survive and resume self-renewal upon reconstitution of Dvl2 expression. Our study underscores a unique regulation mode of the Wnt pathway in ISCs, possibly providing new means of stem cell enrichment for regenerative medicine. © 2017 The Authors.

  5. An essential role of intestinal cell kinase in lung development is linked to the perinatal lethality of human ECO syndrome

    Science.gov (United States)

    Tong, Yixin; Park, So Hyun; Wu, Di; Xu, Wenhao; Guillot, Stacey J.; Jin, Li; Li, Xudong; Wang, Yalin; Lin, Chyuan-Sheng; Fu, Zheng

    2017-01-01

    Human endocrine-cerebro-osteodysplasia (ECO) syndrome, caused by the loss-of-function mutation R272Q in the ICK (intestinal cell kinase) gene, is a neonatal-lethal developmental disorder. To elucidate the molecular basis of ECO syndrome, we constructed an Ick R272Q knock-in mouse model that recapitulates ECO pathological phenotypes. Newborns bearing Ick R272Q homozygous mutations die at birth due to respiratory distress. Ick mutant lungs exhibit not only impaired branching morphogenesis associated with reduced mesenchymal proliferation, but also significant airspace deficiency in primitive alveoli concomitant with abnormal interstitial mesenchymal differentiation. ICK dysfunction induces elongated primary cilia and perturbs ciliary Hedgehog signaling and autophagy during lung sacculation. Our study identifies an essential role for ICK in lung development and advances the mechanistic understanding of ECO syndrome. PMID:28380258

  6. Excessive L-cysteine induces vacuole-like cell death by activating endoplasmic reticulum stress and mitogen-activated protein kinase signaling in intestinal porcine epithelial cells.

    Science.gov (United States)

    Ji, Yun; Wu, Zhenlong; Dai, Zhaolai; Sun, Kaiji; Zhang, Qing; Wu, Guoyao

    2016-01-01

    High intake of dietary cysteine is extremely toxic to animals and the underlying mechanism remains largely unknown. This study was conducted to test the hypothesis that excessive L-cysteine induces cell death by activating endoplasmic reticulum (ER) stress and mitogen-activated protein kinase (MAPK) signaling in intestinal porcine epithelial cells. Jejunal enterocytes were cultured in the presence of 0-10 mmol/L L-cysteine. Cell viability, morphologic alterations, mRNA levels for genes involved in ER stress, protein abundances for glucose-regulated protein 78, C/EBP homologous protein (CHOP), alpha subunit of eukaryotic initiation factor-2 (eIF2α), extracellular signal-regulated kinase (ERK1/2), p38 MAPK, and c-Jun N-terminal protein kinase (JNK1/2) were determined. The results showed that L-cysteine (5-10 mmol/L) reduced cell viability (P L-cysteine were not affected by the autophagy inhibitor 3-methyladenine. The protein abundances for CHOP, phosphorylated (p)-eIF2α, p-JNK1/2, p-p38 MAPK, and the spliced form of XBP-1 mRNA were enhanced (P L-cysteine induces vacuole-like cell death via the activation of ER stress and MAPK signaling in small intestinal epithelial cells. These signaling pathways may be potential targets for developing effective strategies to prevent the toxicity of dietary cysteine.

  7. Intestinal cell kinase, a protein associated with endocrine-cerebro-osteodysplasia syndrome, is a key regulator of cilia length and Hedgehog signaling.

    Science.gov (United States)

    Moon, Heejung; Song, Jieun; Shin, Jeong-Oh; Lee, Hankyu; Kim, Hong-Kyung; Eggenschwiller, Jonathan T; Bok, Jinwoong; Ko, Hyuk Wan

    2014-06-10

    Endocrine-cerebro-osteodysplasia (ECO) syndrome is a recessive genetic disorder associated with multiple congenital defects in endocrine, cerebral, and skeletal systems that is caused by a missense mutation in the mitogen-activated protein kinase-like intestinal cell kinase (ICK) gene. In algae and invertebrates, ICK homologs are involved in flagellar formation and ciliogenesis, respectively. However, it is not clear whether this role of ICK is conserved in mammals and how a lack of functional ICK results in the characteristic phenotypes of human ECO syndrome. Here, we generated Ick knockout mice to elucidate the precise role of ICK in mammalian development and to examine the pathological mechanisms of ECO syndrome. Ick null mouse embryos displayed cleft palate, hydrocephalus, polydactyly, and delayed skeletal development, closely resembling ECO syndrome phenotypes. In cultured cells, down-regulation of Ick or overexpression of kinase-dead or ECO syndrome mutant ICK resulted in an elongation of primary cilia and abnormal Sonic hedgehog (Shh) signaling. Wild-type ICK proteins were generally localized in the proximal region of cilia near the basal bodies, whereas kinase-dead ICK mutant proteins accumulated in the distal part of bulged ciliary tips. Consistent with these observations in cultured cells, Ick knockout mouse embryos displayed elongated cilia and reduced Shh signaling during limb digit patterning. Taken together, these results indicate that ICK plays a crucial role in controlling ciliary length and that ciliary defects caused by a lack of functional ICK leads to abnormal Shh signaling, resulting in congenital disorders such as ECO syndrome.

  8. The promoter for intestinal cell kinase is head-to-head with F-Box 9 and contains functional sites for TCF7L2 and FOXA factors

    Directory of Open Access Journals (Sweden)

    Cohn Steven M

    2010-05-01

    Full Text Available Abstract Background Intestinal cell kinase (ICK; GeneID 22858 is a conserved MAPK and CDK-like kinase that is widely expressed in human tissues. Data from the Cancer Genome Anatomy Project indicated ICK mRNA is increased in cancer, and that its expression correlated with expression of mRNA for an uncharacterized F-box protein, FBX9 (GeneID: 26268. ICK and FBX9 genes are arranged head-to-head on opposite strands, with start sites for transcription separated by ~3.3 kb. We hypothesized ICK and FBX9 are potentially important genes in cancer controlled by a bidirectional promoter. Results We assessed promoter activity of the intergenic region in both orientations in cancer cell lines derived from breast (AU565, SKBR3, colon (HCT-15, KM12, and stomach (AGS cancers, as well as in embryonic human kidney (HEK293T cells. The intergenic segment was active in both orientations in all of these lines, and ICK promoter activity was greater than FBX9 promoter activity. Results from deletions and truncations defined a minimal promoter for ICK, and revealed that repressors and enhancers differentially regulate ICK versus FBX9 promoter activity. The ICK promoter contains consensus motifs for several FOX-family transcription factors that align when mouse and human are compared using EMBOSS. FOXA1 and FOXA2 increase luciferase activity of a minimal promoter 10-20 fold in HEK293T cells. Consensus sites for TCF7L2 (TCF4 (Gene Id: 6934 are also present in both mouse and human. The expression of β-catenin increased activity of the minimal promoter ~10 fold. ICK reference mRNAs (NM_014920.3, NM_016513 are expressed in low copy number and increased in some breast cancers, using a ten base tag 5'-TCAACCTTAT-3' specific for both ICK transcripts. Conclusion ICK and FBX9 are divergently transcribed from a bidirectional promoter that is GC-rich and contains a CpG island. A minimal promoter for ICK contains functional sites for β-cateinin/TCF7L2 and FOXA. These data are

  9. Administration of Protein kinase D1 induce an immunomodulatory effect on lipopolysaccharide-induced intestinal inflammation in a co-culture model of intestinal epithelial Caco-2 cells and RAW 264.7 macrophage cells

    DEFF Research Database (Denmark)

    Nielsen, Ditte Søvsø Gundelund; Fredborg, Marlene; Andersen, Vibeke

    2017-01-01

    the effects of human PKD1 in relation to intestinal inflammation, using a co-culture model of intestinal epithelial Caco-2 cells and RAW264.7 macrophages. An inflammatory response was induced in the macrophages by lipopolysaccharide (LPS), upregulating the expression of tumour necrosis factor alpha (TNF......-α), interleukin- (IL-) 1β, and IL-6 besides increasing the secretion of TNF-α protein. The effect of administering PKD1 to Caco-2 was evaluated in relation to both amelioration of inflammation and the ability to suppress inflammation initiation. Administration of PKD1 (10–100 ng/ml) following induction...

  10. Phosphorylations of Serines 21/9 in Glycogen Synthase Kinase 3α/β Are Not Required for Cell Lineage Commitment or WNT Signaling in the Normal Mouse Intestine.

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    Fiona Hey

    Full Text Available The WNT signalling pathway controls many developmental processes and plays a key role in maintenance of intestine renewal and homeostasis. Glycogen Synthase Kinase 3 (GSK3 is an important component of the WNT pathway and is involved in regulating β-catenin stability and expression of WNT target genes. The mechanisms underpinning GSK3 regulation in this context are not completely understood, with some evidence suggesting this occurs through inhibitory N-terminal serine phosphorylation in a similar way to GSK3 inactivation in insulin signaling. To investigate this in a physiologically relevant context, we have analysed the intestinal phenotype of GSK3 knockin mice in which N-terminal serines 21/9 of GSK3α/β have been mutated to non-phosphorylatable alanine residues. We show that these knockin mutations have very little effect on overall intestinal integrity, cell lineage commitment, β-catenin localization or WNT target gene expression although a small increase in apoptosis at villi tips is observed. Our results provide in vivo evidence that GSK3 is regulated through mechanisms independent of N-terminal serine phosphorylation in order for β-catenin to be stabilised.

  11. TGF-beta1 modulates focal adhesion kinase expression in rat intestinal epithelial IEC-6 cells via stimulatory and inhibitory Smad binding elements.

    Science.gov (United States)

    Walsh, Mary F; Ampasala, Dinakar R; Rishi, Arun K; Basson, Marc D

    2009-02-01

    TGF-beta and FAK modulate cell migration, differentiation, proliferation and apoptosis, and TGF-beta promotes FAK transcription in intestinal epithelial cells via Smad-dependent and independent pathways. We utilized a 1320 bp FAK promoter-luciferase construct to characterize basal and TGF-beta-mediated FAK gene transcription in IEC-6 cells. Inhibiting JNK or Akt negated TGF-beta-stimulated promoter activity; ERK inhibition did not block the TGF-beta effect but increased basal activity. Co-transfection with Co-Smad4 enhanced the TGF-beta response while the inhibitory Smad7 abolished it. Serial deletions sequentially removing the four Smad binding elements (SBE) in the 5' untranslated region of the promoter revealed that the two most distal SBE's are positive regulators while SBE3 exerts a negative influence. Mutational deletion of two upstream p53 sites enhanced basal but did not affect TGF-beta-stimulated increases in promoter activity. TGF-beta increased DNA binding of Smad4, phospho-Smad2/3 and Runx1/AML1a to the most distal 435 bp containing 3 SBE and 2 AML1a sites by ChIP assay. However, although point mutation of SBE1 ablated the TGF-beta-mediated rise in SV40-promoter activity, mutation of AML1a sites did not. TGF-beta regulation of FAK transcription reflects a complex interplay between positive and negative non-Smad signals and SBE's, the last independent of p53 or AML1a.

  12. Update on small intestinal stem cells

    OpenAIRE

    Tesori, Valentina; Puglisi, Maria Ausiliatrice; Lattanzi, Wanda; Gasbarrini, Giovanni Battista; Gasbarrini, Antonio

    2013-01-01

    Among somatic stem cells, those residing in the intestine represent a fascinating and poorly explored research field. Particularly, somatic stem cells reside in the small intestine at the level of the crypt base, in a constant balance between self-renewal and differentiation. Aim of the present review is to delve into the mechanisms that regulate the delicate equilibrium through which intestinal stem cells orchestrate intestinal architecture. To this aim, special focus will be addressed to id...

  13. Update on small intestinal stem cells.

    Science.gov (United States)

    Tesori, Valentina; Puglisi, Maria Ausiliatrice; Lattanzi, Wanda; Gasbarrini, Giovanni Battista; Gasbarrini, Antonio

    2013-08-07

    Among somatic stem cells, those residing in the intestine represent a fascinating and poorly explored research field. Particularly, somatic stem cells reside in the small intestine at the level of the crypt base, in a constant balance between self-renewal and differentiation. Aim of the present review is to delve into the mechanisms that regulate the delicate equilibrium through which intestinal stem cells orchestrate intestinal architecture. To this aim, special focus will be addressed to identify the integrating signals from the surrounding niche, supporting a model whereby distinct cell populations facilitate homeostatic vs injury-induced regeneration.

  14. Giardia duodenalis Surface Cysteine Proteases Induce Cleavage of the Intestinal Epithelial Cytoskeletal Protein Villin via Myosin Light Chain Kinase.

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    Amol Bhargava

    Full Text Available Giardia duodenalis infections are among the most common causes of waterborne diarrhoeal disease worldwide. At the height of infection, G. duodenalis trophozoites induce multiple pathophysiological processes within intestinal epithelial cells that contribute to the development of diarrhoeal disease. To date, our understanding of pathophysiological processes in giardiasis remains incompletely understood. The present study reveals a previously unappreciated role for G. duodenalis cathepsin cysteine proteases in intestinal epithelial pathophysiological processes that occur during giardiasis. Experiments first established that Giardia trophozoites indeed produce cathepsin B and L in strain-dependent fashion. Co-incubation of G. duodenalis with human enterocytes enhanced cathepsin production by Assemblage A (NF and S2 isolates trophozoites, but not when epithelial cells were exposed to Assemblage B (GSM isolate trophozoites. Direct contact between G. duodenalis parasites and human intestinal epithelial monolayers resulted in the degradation and redistribution of the intestinal epithelial cytoskeletal protein villin; these effects were abolished when parasite cathepsin cysteine proteases were inhibited. Interestingly, inhibition of parasite proteases did not prevent degradation of the intestinal tight junction-associated protein zonula occludens 1 (ZO-1, suggesting that G. duodenalis induces multiple pathophysiological processes within intestinal epithelial cells. Finally, this study demonstrates that G. duodenalis-mediated disruption of villin is, at least, in part dependent on activation of myosin light chain kinase (MLCK. Taken together, this study indicates a novel role for parasite cathepsin cysteine proteases in the pathophysiology of G. duodenalis infections.

  15. Intestinal infection with Giardia spp. reduces epithelial barrier function in a myosin light chain kinase-dependent fashion.

    Science.gov (United States)

    Scott, Kevin G-E; Meddings, Jonathon B; Kirk, David R; Lees-Miller, Susan P; Buret, André G

    2002-10-01

    Giardiasis causes malabsorptive diarrhea, and symptoms can be present in the absence of any significant morphologic injury to the intestinal mucosa. The effects of giardiasis on epithelial permeability in vivo remain unknown, and the role of T cells and myosin light chain kinase (MLCK) in altered intestinal barrier function is unclear. This study was conducted to determine whether Giardia spp. alters intestinal permeability in vivo, to assess whether these abnormalities are dependent on T cells, and to assess the role of MLCK in altered epithelial barrier function. Immunocompetent and isogenic athymic mice were inoculated with axenic Giardia muris trophozoites or sterile vehicle (control), then assessed for trophozoite colonization and gastrointestinal permeability. Mechanistic studies using nontransformed human duodenal epithelial monolayers (SCBN) determined the effects of Giardia on myosin light chain (MLC) phosphorylation, transepithelial fluorescein isothiocyanate-dextran fluxes, cytoskeletal F-actin, tight junctional zonula occludens-1 (ZO-1), and MLCK. Giardia infection caused a significant increase in small intestinal, but not gastric or colonic, permeability that correlated with trophozoite colonization in both immunocompetent and athymic mice. In vitro, Giardia increased permeability and phosphorylation of MLC and reorganized F-actin and ZO-1. These alterations were abolished with an MLCK inhibitor. Disruption of small intestinal barrier function is T cell independent, disappears on parasite clearance, and correlates with reorganization of cytoskeletal F-actin and tight junctional ZO-1 in an MLCK-dependent fashion.

  16. Lymphoid cells in chicken intestinal epithelium

    DEFF Research Database (Denmark)

    Bjerregaard, P

    1975-01-01

    The intraepithelial lymphoid cells of chicken small intestine were studied by light microscopy using 1 mu Epon sections, and by electron microscopy. Three cell types were found: small lymphocytes, large lymphoid cells, and granular cells. These cells correspond to the theliolymphocytes and globule...

  17. Focal adhesion kinase is required for intestinal regeneration and tumorigenesis downstream of Wnt/c-Myc signaling

    NARCIS (Netherlands)

    Ashton, Gabrielle H.; Morton, Jennifer P.; Myant, Kevin; Phesse, Toby J.; Ridgway, Rachel A.; Marsh, Victoria; Wilkins, Julie A.; Athineos, Dimitris; Muncan, Vanesa; Kemp, Richard; Neufeld, Kristi; Clevers, Hans; Brunton, Valerie; Winton, Douglas J.; Wang, Xiaoyan; Sears, Rosalie C.; Clarke, Alan R.; Frame, Margaret C.; Sansom, Owen J.

    2010-01-01

    The intestinal epithelium has a remarkable capacity to regenerate after injury and DNA damage. Here, we show that the integrin effector protein Focal Adhesion Kinase (FAK) is dispensable for normal intestinal homeostasis and DNA damage signaling, but is essential for intestinal regeneration

  18. Intestinal endocrine cells in radiation enteritis

    International Nuclear Information System (INIS)

    Pietroletti, R.; Blaauwgeers, J.L.; Taat, C.W.; Simi, M.; Brummelkamp, W.H.; Becker, A.E.

    1989-01-01

    In this study, the intestinal endocrine cells were investigated in 13 surgical specimens affected by radiation enteritis. Endocrine cells were studied by means of Grimelius' silver staining and immunostaining for chromogranin, a general marker of endocrine cells. Positively stained cells were quantified by counting their number per unit length of muscularis mucosa. Results in radiation enteritis were compared with matched control specimens by using Student's t test. Chromogranin immunostaining showed a statistically significant increase of endocrine cells in radiation enteritis specimens compared with controls both in small and large intestine (ileum, 67.5 +/- 23.5 cells per unit length of muscularis mucosa in radiation enteritis versus 17.0 +/- 6.1 in controls; colon, 40.9 +/- 13.7 cells per unit length of muscularis mucosa in radiation enteritis versus 9.5 +/- 4.1 in controls--p less than 0.005 in both instances). Increase of endocrine cells was demonstrated also by Grimelius' staining; however, without reaching statistical significance. It is not clear whether or not the increase of endocrine cells in radiation enteritis reported in this study is caused by a hyperplastic response or by a sparing phenomenon. We should consider that increased endocrine cells, when abnormally secreting their products, may be involved in some of the clinical features of radiation enteropathy. In addition, as intestinal endocrine cells produce trophic substances to the intestine, their increase could be responsible for the raised risk of developing carcinoma of the intestine in long standing radiation enteritis

  19. Intestinal endocrine cells in radiation enteritis

    NARCIS (Netherlands)

    Pietroletti, R.; Blaauwgeers, J. L.; Taat, C. W.; Simi, M.; Brummelkamp, W. H.; Becker, A. E.

    1989-01-01

    In this study, the intestinal endocrine cells were investigated in 13 surgical specimens affected by radiation enteritis. Endocrine cells were studied by means of Grimelius' silver staining and immunostaining for chromogranin, a general marker of endocrine cells. Positively stained cells were

  20. Recent Advances in Intestinal Stem Cells.

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    McCabe, Laura R; Parameswaran, Narayanan

    2017-09-01

    The intestine is a dynamic organ with rapid stem cell division generating epithelial cells that mature and apoptose in 3-5 days. Rapid turnover maintains the epithelial barrier and homeostasis. Current insights on intestinal stem cells (ISCs) and their regulation are discussed here. The Lgr5+ ISCs maintain intestinal homeostasis by dividing asymmetrically, but also divide symmetrically to extinguish or replace ISCs. Following radiation or mucosal injury, reserve BMI1+ ISCs as well as other crypt cells can de-differentiate into Lgr5+ ISCs. ISC niche cells, including Paneth, immune and myofibroblast cells secrete factors that regulate ISC proliferation. Finally, several studies indicate that the microbiome metabolites regulate ISC growth. ISC cells can be plastic and integrate a complexity of environmental/niche cues to trigger or suppress proliferation as needed.

  1. Transcriptome changes during intestinal cell differentiation

    DEFF Research Database (Denmark)

    Tadjali, Mehrdad; Seidelin, Jakob B; Olsen, Jørgen

    2002-01-01

    The expression of 18149 genes have been analysed during the differentiation of the human intestinal cell line Caco-2. cDNA probes from undifferentiated and differentiated Caco-2 cells were separately hybridised to EST DNAs spotted in an array on a nylon membrane. A remarkable change in the transc......The expression of 18149 genes have been analysed during the differentiation of the human intestinal cell line Caco-2. cDNA probes from undifferentiated and differentiated Caco-2 cells were separately hybridised to EST DNAs spotted in an array on a nylon membrane. A remarkable change...... cells by performing reverse transcriptase-polymerase chain reaction on RNA extracted from laser dissected intestinal crypt and villi. In a screen of eight transcripts one - SART3 - was identified as a marker for human colonic crypts....

  2. Myosin Light Chain Kinase Mediates Intestinal Barrier Disruption following Burn Injury

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    Chen, Chuanli; Wang, Pei; Su, Qin; Wang, Shiliang; Wang, Fengjun

    2012-01-01

    Background Severe burn injury results in the loss of intestinal barrier function, however, the underlying mechanism remains unclear. Myosin light chain (MLC) phosphorylation mediated by MLC kinase (MLCK) is critical to the pathophysiological regulation of intestinal barrier function. We hypothesized that the MLCK-dependent MLC phosphorylation mediates the regulation of intestinal barrier function following burn injury, and that MLCK inhibition attenuates the burn-induced intestinal barrier disfunction. Methodology/Principal Findings Male balb/c mice were assigned randomly to either sham burn (control) or 30% total body surface area (TBSA) full thickness burn without or with intraperitoneal injection of ML-9 (2 mg/kg), an MLCK inhibitor. In vivo intestinal permeability to fluorescein isothiocyanate (FITC)-dextran was measured. Intestinal mucosa injury was assessed histologically. Tight junction proteins ZO-1, occludin and claudin-1 was analyzed by immunofluorescent assay. Expression of MLCK and phosphorylated MLC in ileal mucosa was assessed by Western blot. Intestinal permeability was increased significantly after burn injury, which was accompanied by mucosa injury, tight junction protein alterations, and increase of both MLCK and MLC phosphorylation. Treatment with ML-9 attenuated the burn-caused increase of intestinal permeability, mucosa injury, tight junction protein alterations, and decreased MLC phosphorylation, but not MLCK expression. Conclusions/Significance The MLCK-dependent MLC phosphorylation mediates intestinal epithelial barrier dysfunction after severe burn injury. It is suggested that MLCK-dependent MLC phosphorylation may be a critical target for the therapeutic treatment of intestinal epithelial barrier disruption after severe burn injury. PMID:22529961

  3. Myosin light chain kinase mediates intestinal barrier disruption following burn injury.

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    Chuanli Chen

    Full Text Available BACKGROUND: Severe burn injury results in the loss of intestinal barrier function, however, the underlying mechanism remains unclear. Myosin light chain (MLC phosphorylation mediated by MLC kinase (MLCK is critical to the pathophysiological regulation of intestinal barrier function. We hypothesized that the MLCK-dependent MLC phosphorylation mediates the regulation of intestinal barrier function following burn injury, and that MLCK inhibition attenuates the burn-induced intestinal barrier disfunction. METHODOLOGY/PRINCIPAL FINDINGS: Male balb/c mice were assigned randomly to either sham burn (control or 30% total body surface area (TBSA full thickness burn without or with intraperitoneal injection of ML-9 (2 mg/kg, an MLCK inhibitor. In vivo intestinal permeability to fluorescein isothiocyanate (FITC-dextran was measured. Intestinal mucosa injury was assessed histologically. Tight junction proteins ZO-1, occludin and claudin-1 was analyzed by immunofluorescent assay. Expression of MLCK and phosphorylated MLC in ileal mucosa was assessed by Western blot. Intestinal permeability was increased significantly after burn injury, which was accompanied by mucosa injury, tight junction protein alterations, and increase of both MLCK and MLC phosphorylation. Treatment with ML-9 attenuated the burn-caused increase of intestinal permeability, mucosa injury, tight junction protein alterations, and decreased MLC phosphorylation, but not MLCK expression. CONCLUSIONS/SIGNIFICANCE: The MLCK-dependent MLC phosphorylation mediates intestinal epithelial barrier dysfunction after severe burn injury. It is suggested that MLCK-dependent MLC phosphorylation may be a critical target for the therapeutic treatment of intestinal epithelial barrier disruption after severe burn injury.

  4. Inhibition of EV71 by curcumin in intestinal epithelial cells.

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    Huang, Hsing-I; Chio, Chi-Chong; Lin, Jhao-Yin

    2018-01-01

    EV71 is a positive-sense single-stranded RNA virus that belongs to the Picornaviridae family. EV71 infection may cause various symptoms ranging from hand-foot-and-mouth disease to neurological pathological conditions such as aseptic meningitis, ataxia, and acute transverse myelitis. There is currently no effective treatment or vaccine available. Various compounds have been examined for their ability to restrict EV71 replication. However, most experiments have been performed in rhabdomyosarcoma or Vero cells. Since the gastrointestinal tract is the entry site for this pathogen, we anticipated that orally ingested agents may exert beneficial effects by decreasing virus replication in intestinal epithelial cells. In this study, curcumin (diferuloylmethane, C21H20O6), an active ingredient of turmeric (Curcuma longa Linn) with anti-cancer properties, was investigated for its anti-enterovirus activity. We demonstrate that curcumin treatment inhibits viral translation and increases host cell viability. Curcumin does not exert its anti-EV71 effects by modulating virus attachment or virus internal ribosome entry site (IRES) activity. Furthermore, curcumin-mediated regulation of mitogen-activated protein kinase (MAPK) signaling pathways is not involved. We found that protein kinase C delta (PKCδ) plays a role in virus translation in EV71-infected intestinal epithelial cells and that curcumin treatment decreases the phosphorylation of this enzyme. In addition, we show evidence that curcumin also limits viral translation in differentiated human intestinal epithelial cells. In summary, our data demonstrate the anti-EV71 properties of curcumin, suggesting that ingestion of this phytochemical may protect against enteroviral infections.

  5. Inhibition of EV71 by curcumin in intestinal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Hsing-I Huang

    Full Text Available EV71 is a positive-sense single-stranded RNA virus that belongs to the Picornaviridae family. EV71 infection may cause various symptoms ranging from hand-foot-and-mouth disease to neurological pathological conditions such as aseptic meningitis, ataxia, and acute transverse myelitis. There is currently no effective treatment or vaccine available. Various compounds have been examined for their ability to restrict EV71 replication. However, most experiments have been performed in rhabdomyosarcoma or Vero cells. Since the gastrointestinal tract is the entry site for this pathogen, we anticipated that orally ingested agents may exert beneficial effects by decreasing virus replication in intestinal epithelial cells. In this study, curcumin (diferuloylmethane, C21H20O6, an active ingredient of turmeric (Curcuma longa Linn with anti-cancer properties, was investigated for its anti-enterovirus activity. We demonstrate that curcumin treatment inhibits viral translation and increases host cell viability. Curcumin does not exert its anti-EV71 effects by modulating virus attachment or virus internal ribosome entry site (IRES activity. Furthermore, curcumin-mediated regulation of mitogen-activated protein kinase (MAPK signaling pathways is not involved. We found that protein kinase C delta (PKCδ plays a role in virus translation in EV71-infected intestinal epithelial cells and that curcumin treatment decreases the phosphorylation of this enzyme. In addition, we show evidence that curcumin also limits viral translation in differentiated human intestinal epithelial cells. In summary, our data demonstrate the anti-EV71 properties of curcumin, suggesting that ingestion of this phytochemical may protect against enteroviral infections.

  6. Inhibition of EV71 by curcumin in intestinal epithelial cells

    Science.gov (United States)

    Chio, Chi-Chong; Lin, Jhao-Yin

    2018-01-01

    EV71 is a positive-sense single-stranded RNA virus that belongs to the Picornaviridae family. EV71 infection may cause various symptoms ranging from hand-foot-and-mouth disease to neurological pathological conditions such as aseptic meningitis, ataxia, and acute transverse myelitis. There is currently no effective treatment or vaccine available. Various compounds have been examined for their ability to restrict EV71 replication. However, most experiments have been performed in rhabdomyosarcoma or Vero cells. Since the gastrointestinal tract is the entry site for this pathogen, we anticipated that orally ingested agents may exert beneficial effects by decreasing virus replication in intestinal epithelial cells. In this study, curcumin (diferuloylmethane, C21H20O6), an active ingredient of turmeric (Curcuma longa Linn) with anti-cancer properties, was investigated for its anti-enterovirus activity. We demonstrate that curcumin treatment inhibits viral translation and increases host cell viability. Curcumin does not exert its anti-EV71 effects by modulating virus attachment or virus internal ribosome entry site (IRES) activity. Furthermore, curcumin-mediated regulation of mitogen-activated protein kinase (MAPK) signaling pathways is not involved. We found that protein kinase C delta (PKCδ) plays a role in virus translation in EV71-infected intestinal epithelial cells and that curcumin treatment decreases the phosphorylation of this enzyme. In addition, we show evidence that curcumin also limits viral translation in differentiated human intestinal epithelial cells. In summary, our data demonstrate the anti-EV71 properties of curcumin, suggesting that ingestion of this phytochemical may protect against enteroviral infections. PMID:29370243

  7. Transcriptome changes during intestinal cell differentiation

    DEFF Research Database (Denmark)

    Tadjali, Mehrdad; Seidelin, Jakob B; Olsen, Jørgen Lillelund

    2002-01-01

    The expression of 18149 genes have been analysed during the differentiation of the human intestinal cell line Caco-2. cDNA probes from undifferentiated and differentiated Caco-2 cells were separately hybridised to EST DNAs spotted in an array on a nylon membrane. A remarkable change in the transc...

  8. Resveratrol Inhibits Porcine Intestinal Glucose and Alanine Transport: Potential Roles of Na+/K+-ATPase Activity, Protein Kinase A, AMP-Activated Protein Kinase and the Association of Selected Nutrient Transport Proteins with Detergent Resistant Membranes

    Directory of Open Access Journals (Sweden)

    Stefanie Klinger

    2018-03-01

    Full Text Available Background: Beneficial effects of Resveratrol (RSV have been demonstrated, including effects on transporters and channels. However, little is known about how RSV influences intestinal transport. The aim of this study was to further characterize the effects of RSV on intestinal transport and the respective mechanisms. Methods: Porcine jejunum and ileum were incubated with RSV (300 µM, 30 min in Ussing chambers (functional studies and tissue bathes (detection of protein expression, phosphorylation, association with detergent resistant membranes (DRMs. Results: RSV reduced alanine and glucose-induced short circuit currents (ΔIsc and influenced forskolin-induced ΔIsc. The phosphorylation of sodium–glucose-linked transporter 1 (SGLT1, AMP-activated protein kinase (AMPK, protein kinase A substrates (PKA-S and liver kinase B1 (LKB1 increased but a causative relation to the inhibitory effects could not directly be established. The DRM association of SGLT1, peptide transporter 1 (PEPT1 and (phosphorylated Na+/H+-exchanger 3 (NHE3 did not change. Conclusion: RSV influences the intestinal transport of glucose, alanine and chloride and is likely to affect other transport processes. As the effects of protein kinase activation vary between the intestinal localizations, it would appear that increasing cyclic adenosine monophosphate (cAMP levels are part of the mechanism. Nonetheless, the physiological responses depend on cell type-specific structures.

  9. Interactions between the intestinal microbiota and innate lymphoid cells

    Science.gov (United States)

    Chen, Vincent L; Kasper, Dennis L

    2014-01-01

    The mammalian intestine must manage to contain 100 trillion intestinal bacteria without inducing inappropriate immune responses to these microorganisms. The effects of the immune system on intestinal microorganisms are numerous and well-characterized, and recent research has determined that the microbiota influences the intestinal immune system as well. In this review, we first discuss the intestinal immune system and its role in containing and maintaining tolerance to commensal organisms. We next introduce a category of immune cells, the innate lymphoid cells, and describe their classification and function in intestinal immunology. Finally, we discuss the effects of the intestinal microbiota on innate lymphoid cells. PMID:24418741

  10. Wnt, RSPO and Hippo Signalling in the Intestine and Intestinal Stem Cells.

    Science.gov (United States)

    Kriz, Vitezslav; Korinek, Vladimir

    2018-01-08

    In this review, we address aspects of Wnt, R-Spondin (RSPO) and Hippo signalling, in both healthy and transformed intestinal epithelium. In intestinal stem cells (ISCs), the Wnt pathway is essential for intestinal crypt formation and renewal, whereas RSPO-mediated signalling mainly affects ISC numbers. In human colorectal cancer (CRC), aberrant Wnt signalling is the driving mechanism initiating this type of neoplasia. The signalling role of the RSPO-binding transmembrane proteins, the leucine-rich-repeat-containing G-protein-coupled receptors (LGRs), is possibly more pleiotropic and not only limited to the enhancement of Wnt signalling. There is growing evidence for multiple crosstalk between Hippo and Wnt/β-catenin signalling. In the ON state, Hippo signalling results in serine/threonine phosphorylation of Yes-associated protein (YAP1) and tafazzin (TAZ), promoting formation of the β-catenin destruction complex. In contrast, YAP1 or TAZ dephosphorylation (and YAP1 methylation) results in β-catenin destruction complex deactivation and β-catenin nuclear localization. In the Hippo OFF state, YAP1 and TAZ are engaged with the nuclear β-catenin and participate in the β-catenin-dependent transcription program. Interestingly, YAP1/TAZ are dispensable for intestinal homeostasis; however, upon Wnt pathway hyperactivation, the proteins together with TEA domain (TEAD) transcription factors drive the transcriptional program essential for intestinal cell transformation. In addition, in many CRC cells, YAP1 phosphorylation by YES proto-oncogene 1 tyrosine kinase (YES1) leads to the formation of a transcriptional complex that includes YAP1, β-catenin and T-box 5 (TBX5) DNA-binding protein. YAP1/β-catenin/T-box 5-mediated transcription is necessary for CRC cell proliferation and survival. Interestingly, dishevelled (DVL) appears to be an important mediator involved in both Wnt and Hippo (YAP1/TAZ) signalling and some of the DVL functions were assigned to the nuclear DVL

  11. Radiobiology of intestinal epithelium stem cells

    International Nuclear Information System (INIS)

    Konoplyannikova, O.A.

    1988-01-01

    After a single or three-fold whole body irradiation of mice with a dose of 4 Gy and the time interval for the proliferation to be restored (5 days or 3 weeks) the survival curve for stem cells of small intestine epithelium with regard to radiation dose was the same as that for non-preirradiated mice. This indicated that the proliferative potential of stem cells in these experimental conditions was not reduced

  12. Focal Adhesion Kinase Is Required for Intestinal Regeneration and Tumorigenesis Downstream of Wnt/c-Myc Signaling

    Science.gov (United States)

    Ashton, Gabrielle H.; Morton, Jennifer P.; Myant, Kevin; Phesse, Toby J.; Ridgway, Rachel A.; Marsh, Victoria; Wilkins, Julie A.; Athineos, Dimitris; Muncan, Vanesa; Kemp, Richard; Neufeld, Kristi; Clevers, Hans; Brunton, Valerie; Winton, Douglas J.; Wang, Xiaoyan; Sears, Rosalie C.; Clarke, Alan R.; Frame, Margaret C.; Sansom, Owen J.

    2012-01-01

    SUMMARY The intestinal epithelium has a remarkable capacity to regenerate after injury and DNA damage. Here, we show that the integrin effector protein Focal Adhesion Kinase (FAK) is dispensable for normal intestinal homeostasis and DNA damage signaling, but is essential for intestinal regeneration following DNA damage. Given Wnt/c-Myc signaling is activated following intestinal regeneration, we investigated the functional importance of FAK following deletion of the Apc tumor suppressor protein within the intestinal epithelium. Following Apc loss, FAK expression increased in a c-Myc-dependent manner. Codeletion of Apc and Fak strongly reduced proliferation normally induced following Apc loss, and this was associated with reduced levels of phospho-Akt and suppression of intestinal tumorigenesis in Apc heterozygous mice. Thus, FAK is required downstream of Wnt Signaling, for Akt/mTOR activation, intestinal regeneration, and tumorigenesis. Importantly, this work suggests that FAK inhibitors may suppress tumorigenesis in patients at high risk of developing colorectal cancer. PMID:20708588

  13. IKKα Promotes Intestinal Tumorigenesis by Limiting Recruitment of M1-like Polarized Myeloid Cells

    Directory of Open Access Journals (Sweden)

    Serkan I. Göktuna

    2014-06-01

    Full Text Available The recruitment of immune cells into solid tumors is an essential prerequisite of tumor development. Depending on the prevailing polarization profile of these infiltrating leucocytes, tumorigenesis is either promoted or blocked. Here, we identify IκB kinase α (IKKα as a central regulator of a tumoricidal microenvironment during intestinal carcinogenesis. Mice deficient in IKKα kinase activity are largely protected from intestinal tumor development that is dependent on the enhanced recruitment of interferon γ (IFNγ-expressing M1-like myeloid cells. In IKKα mutant mice, M1-like polarization is not controlled in a cell-autonomous manner but, rather, depends on the interplay of both IKKα mutant tumor epithelia and immune cells. Because therapies aiming at the tumor microenvironment rather than directly at the mutated cancer cell may circumvent resistance development, we suggest IKKα as a promising target for colorectal cancer (CRC therapy.

  14. Intestinal Stem Cell Niche: The Extracellular Matrix and Cellular Components

    Directory of Open Access Journals (Sweden)

    Laween Meran

    2017-01-01

    Full Text Available The intestinal epithelium comprises a monolayer of polarised columnar cells organised along the crypt-villus axis. Intestinal stem cells reside at the base of crypts and are constantly nourished by their surrounding niche for maintenance, self-renewal, and differentiation. The cellular microenvironment including the adjacent Paneth cells, stromal cells, smooth muscle cells, and neural cells as well as the extracellular matrix together constitute the intestinal stem cell niche. A dynamic regulatory network exists among the epithelium, stromal cells, and the matrix via complex signal transduction to maintain tissue homeostasis. Dysregulation of these biological or mechanical signals could potentially lead to intestinal injury and disease. In this review, we discuss the role of different intestinal stem cell niche components and dissect the interaction between dynamic matrix factors and regulatory signalling during intestinal stem cell homeostasis.

  15. Endocrine cells in the denervated intestine

    Science.gov (United States)

    Santos, Gilda C; Zucoloto, Sérgio; Garcia, Sérgio B

    2000-01-01

    This study deals with the effects of myenteric denervation of the proximal jejunum on endocrine cell population of the crypt-villus unit, 5 months after treatment with benzalkonium chloride (BAC). Male Wistar albino rats weighing on average 100 g were allocated to two groups: the BAC group − the proximal jejunal serosa was treated with 2 mm BAC for 30 min, and the control group − treated with saline solution (0,9% NaCl). There was a significant reduction in neurone number in the jejunal myenteric plexus of the BAC group and the endocrine cell population (serotoninergic and argyrophilic cells) was significantly increased in this intestine segment. In conclusion, the present findings provide further evidence that the myenteric denervation induced by BAC may lead to the development of a local imbalance of the neurotransmitters, with a consequent induction of enteroendocrine cell (argyrophilic and serotoninergic cells) hyperplasia in the crypt and villus. PMID:10971748

  16. Intestinal Stem Cell Dynamics: A Story of Mice and Humans.

    Science.gov (United States)

    Hodder, Michael C; Flanagan, Dustin J; Sansom, Owen J

    2018-06-01

    Stem cell dynamics define the probability of accumulating mutations within the intestinal epithelium. In this issue of Cell Stem Cell, Nicholson et al. (2018) report that human intestinal stem cell dynamics differ significantly from those of mice and establish that oncogenic mutations are more likely to expand; therefore, "normal" epithelium may carry multiple mutations. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Sequential cancer mutations in cultured human intestinal stem cells

    NARCIS (Netherlands)

    Drost, Jarno; van Jaarsveld, Richard H.; Ponsioen, Bas; Zimberlin, Cheryl; van Boxtel, Ruben; Buijs, Arjan; Sachs, Norman; Overmeer, René M.; Offerhaus, G. Johan; Begthel, Harry; Korving, Jeroen; van de Wetering, Marc; Schwank, Gerald; Logtenberg, Meike; Cuppen, Edwin; Snippert, Hugo J.; Medema, Jan Paul; Kops, Geert J. P. L.; Clevers, Hans

    2015-01-01

    Crypt stem cells represent the cells of origin for intestinal neoplasia. Both mouse and human intestinal stem cells can be cultured in medium containing the stem-cell-niche factors WNT, R-spondin, epidermal growth factor (EGF) and noggin over long time periods as epithelial organoids that remain

  18. Protective effect of NSA on intestinal epithelial cells in a necroptosis model.

    Science.gov (United States)

    Dong, Wei; Zhang, Min; Zhu, Yaxi; Chen, Yuanhan; Zhao, Xingchen; Li, Ruizhao; Zhang, Li; Ye, Zhiming; Liang, Xingling

    2017-10-17

    This study aimed to investigate the protective effect of the necroptosis inhibitor necrosulfonamide (NSA) on intestinal epithelial cells using a novel in vitro necroptosis model that mimics inflammatory bowel disease (IBD). 2,4,6-trinitrobenzenesulfonic acid (TNBS) was perfused into the rectum of BALB/c mice to established a colitis model. Pathologic injury and cell death were evaluated. A novel in vitro model of necroptosis was established in Caco-2 cells using TNF- α and Z-VAD-fmk, and the cells were treated with or without NSA. Morphologic changes, manner of cell death and the levels of phosphorylation of receptor-interacting protein kinase 3 (p-RIPK3) and mixed-lineage kinase domain-like (p-MLKL) were detected. In the TNBS-induced colitis in mice, TUNEL-positive and caspase-3-negative cells were observed in the intestinal mucosa, and p-RIPK3 was found to be elevated. Under the stimulation of TNF- α and Z-VAD-fmk, the morphologic damage in the Caco-2 cells was aggravated, the proportion of necrosis was increased, and the level of p-RIPK3 and p-MLKL were increased, confirming that the regulated cell death was necroptosis. NSA reversed the morphological abnormalities and reduced necrotic cell death induced by TNF- α and Z-VAD-fmk. NSA can inhibit necroptosis in intestinal epithelial cells in vitro and might confer a potential protective effect against IBD.

  19. Controlling the frontier: regulatory T-cells and intestinal homeostasis.

    Science.gov (United States)

    Bollrath, Julia; Powrie, Fiona M

    2013-11-30

    The intestine represents one of the most challenging sites for the immune system as immune cells must be able to mount an efficient response to invading pathogens while tolerating the large number and diverse array of resident commensal bacteria. Foxp3(+) regulatory T-cells (Tregs) play a non-redundant role at maintaining this balance. At the same time Treg cell differentiation and function can be modulated by the intestinal microbiota. In this review, we will discuss effector mechanisms of Treg cells in the intestine and how these cells can be influenced by the intestinal microbiota. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. IRF8 Transcription-Factor-Dependent Classical Dendritic Cells Are Essential for Intestinal T Cell Homeostasis

    DEFF Research Database (Denmark)

    Luda, Katarzyna M.; Joeris, Thorsten; Persson, Emma K.

    2016-01-01

    The role of dendritic cells (DCs) in intestinal immune homeostasis remains incompletely defined. Here we show that mice lacking IRF8 transcription-factor-dependent DCs had reduced numbers of T cells in the small intestine (SI), but not large intestine (LI), including an almost complete absence...... dependent DCs in the maintenance of intestinal T cell homeostasis....

  1. Innate Lymphoid Cells in Intestinal Inflammation

    Science.gov (United States)

    Geremia, Alessandra; Arancibia-Cárcamo, Carolina V.

    2017-01-01

    Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the intestine that encompasses Crohn’s disease (CD) and ulcerative colitis. The cause of IBD is unknown, but the evidence suggests that an aberrant immune response toward the commensal bacterial flora is responsible for disease in genetically susceptible individuals. Results from animal models of colitis and human studies indicate a role for innate lymphoid cells (ILC) in the pathogenesis of chronic intestinal inflammation in IBD. ILC are a population of lymphocytes that are enriched at mucosal sites, where they play a protective role against pathogens including extracellular bacteria, helminthes, and viruses. ILC lack an antigen-specific receptor, but can respond to environmental stress signals contributing to the rapid orchestration of an early immune response. Several subsets of ILC reflecting functional characteristics of T helper subsets have been described. ILC1 express the transcription factor T-bet and are characterized by secretion of IFNγ, ILC2 are GATA3+ and secrete IL5 and IL13 and ILC3 depend on expression of RORγt and secrete IL17 and IL22. However, ILC retain a degree of plasticity depending on exposure to cytokines and environmental factors. IL23 responsive ILC have been implicated in the pathogenesis of colitis in several innate murine models through the production of IL17, IFNγ, and GM-CSF. We have previously identified IL23 responsive ILC in the human intestine and found that they accumulate in the inflamed colon and small bowel of patients with CD. Other studies have confirmed accumulation of ILC in CD with increased frequencies of IFNγ-secreting ILC1 in both the intestinal lamina propria and the epithelium. Moreover, IL23 driven IL22 producing ILC have been shown to drive bacteria-induced colitis-associated cancer in mice. Interestingly, our data show increased ILC accumulation in patients with IBD and primary sclerosing cholangitis, who carry an increased risk of

  2. Innate Lymphoid Cells in Intestinal Inflammation

    Directory of Open Access Journals (Sweden)

    Alessandra Geremia

    2017-10-01

    Full Text Available Inflammatory bowel disease (IBD is a chronic inflammatory disorder of the intestine that encompasses Crohn’s disease (CD and ulcerative colitis. The cause of IBD is unknown, but the evidence suggests that an aberrant immune response toward the commensal bacterial flora is responsible for disease in genetically susceptible individuals. Results from animal models of colitis and human studies indicate a role for innate lymphoid cells (ILC in the pathogenesis of chronic intestinal inflammation in IBD. ILC are a population of lymphocytes that are enriched at mucosal sites, where they play a protective role against pathogens including extracellular bacteria, helminthes, and viruses. ILC lack an antigen-specific receptor, but can respond to environmental stress signals contributing to the rapid orchestration of an early immune response. Several subsets of ILC reflecting functional characteristics of T helper subsets have been described. ILC1 express the transcription factor T-bet and are characterized by secretion of IFNγ, ILC2 are GATA3+ and secrete IL5 and IL13 and ILC3 depend on expression of RORγt and secrete IL17 and IL22. However, ILC retain a degree of plasticity depending on exposure to cytokines and environmental factors. IL23 responsive ILC have been implicated in the pathogenesis of colitis in several innate murine models through the production of IL17, IFNγ, and GM-CSF. We have previously identified IL23 responsive ILC in the human intestine and found that they accumulate in the inflamed colon and small bowel of patients with CD. Other studies have confirmed accumulation of ILC in CD with increased frequencies of IFNγ-secreting ILC1 in both the intestinal lamina propria and the epithelium. Moreover, IL23 driven IL22 producing ILC have been shown to drive bacteria-induced colitis-associated cancer in mice. Interestingly, our data show increased ILC accumulation in patients with IBD and primary sclerosing cholangitis, who carry an

  3. Evolutionary insights into postembryonic development of adult intestinal stem cells

    Directory of Open Access Journals (Sweden)

    Ishizuya-Oka Atsuko

    2011-11-01

    Full Text Available Abstract In the adult vertebrate intestine, multi-potent stem cells continuously generate all of the epithelial cells throughout the adulthood. While it has long been known that the frog intestine is formed via the development of adult intestinal stem cells during thyroid hormone (TH-dependent metamorphosis, the basic structure of the adult intestine is formed by birth in mammals and it is unclear if the subsequent maturation of the intestine involves any changes in the intestinal stem cells. Two recent papers showing that B lymphocyte-induced maturation protein 1 (Blimp1 regulates postnatal epithelial stem cell reprogramming during mouse intestinal maturation support the model that adult intestinal stem cells are developed during postembryonic development in mammals, in a TH-dependent process similar to intestinal remodeling during amphibian metamorphosis. Since the formation of the adult intestine in both mammals and amphibians is closely associated with the adaptation from aquatic to terrestrial life during the peak of endogenous TH levels, the molecular mechanisms by which the adult stem cells are developed are likely evolutionally conserved.

  4. Microenvironmental regulation of stem cells in intestinal homeostasis and cancer

    NARCIS (Netherlands)

    Medema, Jan Paul; Vermeulen, Louis

    2011-01-01

    The identification of intestinal stem cells as well as their malignant counterparts, colon cancer stem cells, has undergone rapid development in recent years. Under physiological conditions, intestinal homeostasis is a carefully balanced and efficient interplay between stem cells, their progeny and

  5. Paneth cells, antimicrobial peptides and maintenance of intestinal homeostasis.

    Science.gov (United States)

    Bevins, Charles L; Salzman, Nita H

    2011-05-01

    Building and maintaining a homeostatic relationship between a host and its colonizing microbiota entails ongoing complex interactions between the host and the microorganisms. The mucosal immune system, including epithelial cells, plays an essential part in negotiating this equilibrium. Paneth cells (specialized cells in the epithelium of the small intestine) are an important source of antimicrobial peptides in the intestine. These cells have become the focus of investigations that explore the mechanisms of host-microorganism homeostasis in the small intestine and its collapse in the processes of infection and chronic inflammation. In this Review, we provide an overview of the intestinal microbiota and describe the cell biology of Paneth cells, emphasizing the composition of their secretions and the roles of these cells in intestinal host defence and homeostasis. We also highlight the implications of Paneth cell dysfunction in susceptibility to chronic inflammatory bowel disease.

  6. Protein kinase activity of phosphoinositide 3-kinase regulates cytokine-dependent cell survival.

    Directory of Open Access Journals (Sweden)

    Daniel Thomas

    Full Text Available The dual specificity protein/lipid kinase, phosphoinositide 3-kinase (PI3K, promotes growth factor-mediated cell survival and is frequently deregulated in cancer. However, in contrast to canonical lipid-kinase functions, the role of PI3K protein kinase activity in regulating cell survival is unknown. We have employed a novel approach to purify and pharmacologically profile protein kinases from primary human acute myeloid leukemia (AML cells that phosphorylate serine residues in the cytoplasmic portion of cytokine receptors to promote hemopoietic cell survival. We have isolated a kinase activity that is able to directly phosphorylate Ser585 in the cytoplasmic domain of the interleukin 3 (IL-3 and granulocyte macrophage colony stimulating factor (GM-CSF receptors and shown it to be PI3K. Physiological concentrations of cytokine in the picomolar range were sufficient for activating the protein kinase activity of PI3K leading to Ser585 phosphorylation and hemopoietic cell survival but did not activate PI3K lipid kinase signaling or promote proliferation. Blockade of PI3K lipid signaling by expression of the pleckstrin homology of Akt1 had no significant impact on the ability of picomolar concentrations of cytokine to promote hemopoietic cell survival. Furthermore, inducible expression of a mutant form of PI3K that is defective in lipid kinase activity but retains protein kinase activity was able to promote Ser585 phosphorylation and hemopoietic cell survival in the absence of cytokine. Blockade of p110α by RNA interference or multiple independent PI3K inhibitors not only blocked Ser585 phosphorylation in cytokine-dependent cells and primary human AML blasts, but also resulted in a block in survival signaling and cell death. Our findings demonstrate a new role for the protein kinase activity of PI3K in phosphorylating the cytoplasmic tail of the GM-CSF and IL-3 receptors to selectively regulate cell survival highlighting the importance of targeting

  7. RON kinase isoforms demonstrate variable cell motility in normal cells.

    Science.gov (United States)

    Greenbaum, Alissa; Rajput, Ashwani; Wan, Guanghua

    2016-09-01

    Aberrant RON (Recepteur d'Origine Nantais) tyrosine kinase activation causes the epithelial cell to evade normal growth pathways, resulting in unregulated cell proliferation, increased cell motility and decreased apoptosis. Wildtype (wt) RON has been shown to play a role in metastasis of epithelial malignancies. It presents an important potential therapeutic target for colorectal, breast, gastric and pancreatic cancer. Little is known about functional differences amongst RON isoforms RON155, RON160 and RON165. The purpose of this study was to determine the effect of various RON kinase isoforms on cell motility. Cell lines with stable expression of wtRON were generated by inserting the coding region of RON in pTagRFP (tagged red fluorescence protein plasmid). The expression constructs of RON variants (RON155, RON160 and RON165) were generated by creating a mutagenesis-based wtRON-pTag RFP plasmid and stably transfected into HEK 293 cells. The wound closure scratch assay was used to investigate the effect on cell migratory capacity of wild type RON and its variants. RON transfected cells demonstrated increased cell motility compared to HEK293 control cells. RON165 cell motility was significantly increased compared to RON160 (mean percentage of wound covered 37.37% vs. 32.40%; p = 0.03). RON tyrosine kinase isoforms have variable cell motility. This may reflect a difference in the behavior of malignant epithelial cells and their capacity for metastasis.

  8. Wnt, stem cells and cancer in the intestine.

    NARCIS (Netherlands)

    Pinto, D.; Clevers, J.C.

    2005-01-01

    The intestinal epithelium is a self-renewing tissue which represents a unique model for studying interconnected cellular processes such as proliferation, differentiation, cell migration and carcinogenesis. Although the stem cells of the intestine have not yet been physically characterized or

  9. Stem cell self-renewal in intestinal crypt

    NARCIS (Netherlands)

    Simons, B.D.; Clevers, H.

    2011-01-01

    As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine

  10. Abnormal Wnt and PI3Kinase signaling in the malformed intestine of lama5 deficient mice.

    Directory of Open Access Journals (Sweden)

    Léa Ritié

    Full Text Available Laminins are major constituents of basement membranes and are essential for tissue homeostasis. Laminin-511 is highly expressed in the intestine and its absence causes severe malformation of the intestine and embryonic lethality. To understand the mechanistic role of laminin-511 in tissue homeostasis, we used RNA profiling of embryonic intestinal tissue of lama5 knockout mice and identified a lama5 specific gene expression signature. By combining cell culture experiments with mediated knockdown approaches, we provide a mechanistic link between laminin α5 gene deficiency and the physiological phenotype. We show that laminin α5 plays a crucial role in both epithelial and mesenchymal cell behavior by inhibiting Wnt and activating PI3K signaling. We conclude that conflicting signals are elicited in the absence of lama5, which alter cell adhesion, migration as well as epithelial and muscle differentiation. Conversely, adhesion to laminin-511 may serve as a potent regulator of known interconnected PI3K/Akt and Wnt signaling pathways. Thus deregulated adhesion to laminin-511 may be instrumental in diseases such as human pathologies of the gut where laminin-511 is abnormally expressed as it is shown here.

  11. Regulation of intestinal homeostasis by innate immune cells.

    Science.gov (United States)

    Kayama, Hisako; Nishimura, Junichi; Takeda, Kiyoshi

    2013-12-01

    The intestinal immune system has an ability to distinguish between the microbiota and pathogenic bacteria, and then activate pro-inflammatory pathways against pathogens for host defense while remaining unresponsive to the microbiota and dietary antigens. In the intestine, abnormal activation of innate immunity causes development of several inflammatory disorders such as inflammatory bowel diseases (IBD). Thus, activity of innate immunity is finely regulated in the intestine. To date, multiple innate immune cells have been shown to maintain gut homeostasis by preventing inadequate adaptive immune responses in the murine intestine. Additionally, several innate immune subsets, which promote Th1 and Th17 responses and are implicated in the pathogenesis of IBD, have recently been identified in the human intestinal mucosa. The demonstration of both murine and human intestinal innate immune subsets contributing to regulation of adaptive immunity emphasizes the conserved innate immune functions across species and might promote development of the intestinal innate immunity-based clinical therapy.

  12. Thyroid hormone regulation of adult intestinal stem cells: Implications on intestinal development and homeostasis.

    Science.gov (United States)

    Sun, Guihong; Roediger, Julia; Shi, Yun-Bo

    2016-12-01

    Organ-specific adult stem cells are essential for organ homeostasis, tissue repair and regeneration. The formation of such stem cells often takes place during postembryonic development, a period around birth in mammals when plasma thyroid hormone concentration is high. The life-long self-renewal of the intestinal epithelium has made mammalian intestine a valuable model to study the function and regulation and adult stem cells. On the other hand, much less is known about how the adult intestinal stem cells are formed during vertebrate development. Here, we will review some recent progresses on this subject, focusing mainly on the formation of the adult intestine during Xenopus metamorphosis. We will discuss the role of thyroid hormone signaling pathway in the process and potential molecular conservations between amphibians and mammals as well as the implications in organ homeostasis and human diseases.

  13. Stem cell self-renewal in intestinal crypt

    International Nuclear Information System (INIS)

    Simons, Benjamin D.; Clevers, Hans

    2011-01-01

    As a rapidly cycling tissue capable of fast repair and regeneration, the intestinal epithelium has emerged as a favored model system to explore the principles of adult stem cell biology. However, until recently, the identity and characteristics of the stem cell population in both the small intestine and colon has remained the subject of debate. Recent studies based on targeted lineage tracing strategies, combined with the development of an organotypic culture system, have identified the crypt base columnar cell as the intestinal stem cell, and have unveiled the strategy by which the balance between proliferation and differentiation is maintained. These results show that intestinal stem cells operate in a dynamic environment in which frequent and stochastic stem cell loss is compensated by the proliferation of neighboring stem cells. We review the basis of these experimental findings and the insights they offer into the mechanisms of homeostatic stem cell regulation.

  14. Type 3 innate lymphoid cells maintain intestinal epithelial stem cells after tissue damage

    NARCIS (Netherlands)

    P. Aparicio-Domingo (Patricia); M. Romera Hernández (Mónica); J.J. Karrich (Julien J.); F.H.J. Cornelissen (Ferry); N. Papazian (Natalie); D.J. Lindenbergh-Kortleve (Dicky); J.A. Butler (James A.); L. Boon (Louis); M. Coles (Mark); J.N. Samsom (Janneke); T. Cupedo (Tom)

    2015-01-01

    textabstractDisruption of the intestinal epithelial barrier allows bacterial translocation and predisposes to destructive inflammation. To ensure proper barrier composition, crypt-residing stem cells continuously proliferate and replenish all intestinal epithelial cells within days. As a consequence

  15. Intestinal Stem Cell Markers in the Intestinal Metaplasia of Stomach and Barrett's Esophagus.

    Directory of Open Access Journals (Sweden)

    Bo Gun Jang

    Full Text Available Gastric intestinal metaplasia (IM is a highly prevalent preneoplastic lesion; however, the molecular mechanisms regulating its development remain unclear. We have previously shown that a population of cells expressing the intestinal stem cell (ISC marker LGR5 increases remarkably in IM. In this study, we further investigated the molecular characteristics of these LGR5+ cells in IM by examining the expression profile of several ISC markers. Notably, we found that ISC markers-including OLFM4 and EPHB2-are positively associated with the CDX2 expression in non-tumorous gastric tissues. This finding was confirmed in stomach lesions with or without metaplasia, which demonstrated that OLFM4 and EPHB2 expression gradually increased with metaplastic progression. Moreover, RNA in situ hybridization revealed that LGR5+ cells coexpress several ISC markers and remained confined to the base of metaplastic glands, reminiscent to that of normal intestinal crypts, whereas those in normal antral glands expressed none of these markers. Furthermore, a large number of ISC marker-expressing cells were diffusely distributed in gastric adenomas, suggesting that these markers may facilitate gastric tumorigenesis. In addition, Barrett's esophagus (BE-which is histologically similar to intestinal metaplasia-exhibited a similar distribution of ISC markers, indicating the presence of a stem cell population with intestinal differentiation potential. In conclusion, we identified that LGR5+ cells in gastric IM and BE coexpress ISC markers, and exhibit the same expression profile as those found in normal intestinal crypts. Taken together, these results implicate an intestinal-like stem cell population in the pathogenesis of IM, and provide an important basis for understanding the development and maintenance of this disease.

  16. Bovine lactoferrin regulates cell survival, apoptosis and inflammation in intestinal epithelial cells and preterm pig intestine.

    Science.gov (United States)

    Nguyen, Duc Ninh; Jiang, Pingping; Stensballe, Allan; Bendixen, Emøke; Sangild, Per T; Chatterton, Dereck E W

    2016-04-29

    Bovine lactoferrin (bLF) may modulate neonatal intestinal inflammation. Previous studies in intestinal epithelial cells (IECs) indicated that moderate bLF doses enhance proliferation whereas high doses trigger inflammation. To further elucidate cellular mechanisms, we profiled the porcine IEC proteome after stimulation with bLF at 0, 0.1, 1 and 10g/L by LC-MS-based proteomics. Key pathways were analyzed in the intestine of formula-fed preterm pigs with and without supplementation of 10g/L bLF. Levels of 123 IEC proteins were altered by bLF. Low bLF doses (0.1-1g/L) up-regulated 11 proteins associated with glycolysis, energy metabolism and protein synthesis, indicating support of cell survival. In contrast, a high bLF dose (10g/L) up-regulated three apoptosis-inducing proteins, down-regulated five anti-apoptotic and proliferation-inducing proteins and 15 proteins related to energy and amino acid metabolism, and altered three proteins enhancing the hypoxia inducible factor-1 (HIF-1) pathway. In the preterm pig intestine, bLF at 10g/L decreased villus height/crypt depth ratio and up-regulated the Bax/Bcl-2 ratio and HIF-1α, indicating elevated intestinal apoptosis and inflammation. In conclusion, bLF dose-dependently affects IECs via metabolic, apoptotic and inflammatory pathways. It is important to select an appropriate dose when feeding neonates with bLF to avoid detrimental effects exerted by excessive doses. The present work elucidates dose-dependent effects of bLF on the proteomic changes of IECs in vitro supplemented with data from a preterm pig study confirming detrimental effects of enteral feeding with the highest dose of bLF (10g/L). The study contributes to further understanding on mechanisms that bLF, as an important milk protein, can regulate the homeostasis of the immature intestine. Results from this study urge neonatologists to carefully consider the dose of bLF to supplement into infant formula used for preterm neonates. Copyright © 2016 Elsevier B

  17. Protein kinase C signaling and cell cycle regulation

    OpenAIRE

    Black, Adrian R.; Black, Jennifer D.

    2013-01-01

    A link between T cell proliferation and the protein kinase C (PKC) family of serine/threonine kinases has been recognized for about thirty years. However, despite the wealth of information on PKC-mediated control of T cell activation, understanding of the effects of PKCs on the cell cycle machinery in this cell type remains limited. Studies in other systems have revealed important cell cycle-specific effects of PKC signaling that can either positively or negatively impact proliferation. Th...

  18. Fluorescent labelling of intestinal epithelial cells reveals independent long-lived intestinal stem cells in a crypt

    International Nuclear Information System (INIS)

    Horita, Nobukatsu; Tsuchiya, Kiichiro; Hayashi, Ryohei; Fukushima, Keita; Hibiya, Shuji; Fukuda, Masayoshi; Kano, Yoshihito; Mizutani, Tomohiro; Nemoto, Yasuhiro; Yui, Shiro; Okamoto, Ryuichi; Nakamura, Tetsuya; Watanabe, Mamoru

    2014-01-01

    Highlights: • Lentivirus mixed with Matrigel enables direct infection of intestinal organoids. • Our original approach allows the marking of a single stem cell in a crypt. • Time-lapse imaging shows the dynamics of a single stem cell. • Our lentivirus transgene system demonstrates plural long-lived stem cells in a crypt. - Abstract: Background and aims: The dynamics of intestinal stem cells are crucial for regulation of intestinal function and maintenance. Although crypt stem cells have been identified in the intestine by genetic marking methods, identification of plural crypt stem cells has not yet been achieved as they are visualised in the same colour. Methods: Intestinal organoids were transferred into Matrigel® mixed with lentivirus encoding mCherry. The dynamics of mCherry-positive cells was analysed using time-lapse imaging, and the localisation of mCherry-positive cells was analysed using 3D immunofluorescence. Results: We established an original method for the introduction of a transgene into an organoid generated from mouse small intestine that resulted in continuous fluorescence of the mCherry protein in a portion of organoid cells. Three-dimensional analysis using confocal microscopy showed a single mCherry-positive cell in an organoid crypt that had been cultured for >1 year, which suggested the presence of long-lived mCherry-positive and -negative stem cells in the same crypt. Moreover, a single mCherry-positive stem cell in a crypt gave rise to both crypt base columnar cells and transit amplifying cells. Each mCherry-positive and -negative cell contributed to the generation of organoids. Conclusions: The use of our original lentiviral transgene system to mark individual organoid crypt stem cells showed that long-lived plural crypt stem cells might independently serve as intestinal epithelial cells, resulting in the formation of a completely functional villus

  19. Fluorescent labelling of intestinal epithelial cells reveals independent long-lived intestinal stem cells in a crypt

    Energy Technology Data Exchange (ETDEWEB)

    Horita, Nobukatsu [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University (Japan); Tsuchiya, Kiichiro, E-mail: kii.gast@tmd.ac.jp [Department of Advanced Therapeutics for Gastrointestinal Diseases, Graduate School, Tokyo Medical and Dental University (Japan); Hayashi, Ryohei [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University (Japan); Department of Gastroenterology and Metabolism, Hiroshima University (Japan); Fukushima, Keita; Hibiya, Shuji; Fukuda, Masayoshi; Kano, Yoshihito; Mizutani, Tomohiro; Nemoto, Yasuhiro; Yui, Shiro [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University (Japan); Okamoto, Ryuichi; Nakamura, Tetsuya [Department of Advanced Therapeutics for Gastrointestinal Diseases, Graduate School, Tokyo Medical and Dental University (Japan); Watanabe, Mamoru [Department of Gastroenterology and Hepatology, Graduate School, Tokyo Medical and Dental University (Japan)

    2014-11-28

    Highlights: • Lentivirus mixed with Matrigel enables direct infection of intestinal organoids. • Our original approach allows the marking of a single stem cell in a crypt. • Time-lapse imaging shows the dynamics of a single stem cell. • Our lentivirus transgene system demonstrates plural long-lived stem cells in a crypt. - Abstract: Background and aims: The dynamics of intestinal stem cells are crucial for regulation of intestinal function and maintenance. Although crypt stem cells have been identified in the intestine by genetic marking methods, identification of plural crypt stem cells has not yet been achieved as they are visualised in the same colour. Methods: Intestinal organoids were transferred into Matrigel® mixed with lentivirus encoding mCherry. The dynamics of mCherry-positive cells was analysed using time-lapse imaging, and the localisation of mCherry-positive cells was analysed using 3D immunofluorescence. Results: We established an original method for the introduction of a transgene into an organoid generated from mouse small intestine that resulted in continuous fluorescence of the mCherry protein in a portion of organoid cells. Three-dimensional analysis using confocal microscopy showed a single mCherry-positive cell in an organoid crypt that had been cultured for >1 year, which suggested the presence of long-lived mCherry-positive and -negative stem cells in the same crypt. Moreover, a single mCherry-positive stem cell in a crypt gave rise to both crypt base columnar cells and transit amplifying cells. Each mCherry-positive and -negative cell contributed to the generation of organoids. Conclusions: The use of our original lentiviral transgene system to mark individual organoid crypt stem cells showed that long-lived plural crypt stem cells might independently serve as intestinal epithelial cells, resulting in the formation of a completely functional villus.

  20. Role of Bruton's tyrosine kinase in B cells and malignancies

    NARCIS (Netherlands)

    Pal Singh, S. (Simar); F. Dammeijer (Floris); R.W. Hendriks (Rudi)

    2018-01-01

    textabstractBruton's tyrosine kinase (BTK) is a non-receptor kinase that plays a crucial role in oncogenic signaling that is critical for proliferation and survival of leukemic cells in many B cell malignancies. BTK was initially shown to be defective in the primary immunodeficiency X-linked

  1. Desmoglein 2 regulates the intestinal epithelial barrier via p38 mitogen-activated protein kinase.

    Science.gov (United States)

    Ungewiß, Hanna; Vielmuth, Franziska; Suzuki, Shintaro T; Maiser, Andreas; Harz, Hartmann; Leonhardt, Heinrich; Kugelmann, Daniela; Schlegel, Nicolas; Waschke, Jens

    2017-07-24

    Intestinal epithelial barrier properties are maintained by a junctional complex consisting of tight junctions (TJ), adherens junctions (AJ) and desmosomes. Desmoglein 2 (Dsg2), an adhesion molecule of desmosomes and the only Dsg isoform expressed in enterocytes, is required for epithelial barrier properties and may contribute to barrier defects in Crohn's disease. Here, we identified extradesmosomal Dsg2 on the surface of polarized enterocytes by Triton extraction, confocal microscopy, SIM and STED. Atomic force microscopy (AFM) revealed Dsg2-specific binding events along the cell border on the surface of enterocytes with a mean unbinding force of around 30pN. Binding events were blocked by an inhibitory antibody targeting Dsg2 which under same conditions activated p38MAPK but did not reduce cell cohesion. In enterocytes deficient for Dsg2, p38MAPK activity was reduced and both barrier integrity and reformation were impaired. Dsc2 rescue did not restore p38MAPK activity indicating that Dsg2 is required. Accordingly, direct activation of p38MAPK in Dsg2-deficient cells enhanced barrier reformation demonstrating that Dsg2-mediated activation of p38MAPK is crucial for barrier function. Collectively, our data show that Dsg2, beside its adhesion function, regulates intestinal barrier function via p38MAPK signalling. This is in contrast to keratinocytes and points towards tissue-specific signalling functions of desmosomal cadherins.

  2. Activated STAT5 Confers Resistance to Intestinal Injury by Increasing Intestinal Stem Cell Proliferation and Regeneration

    Directory of Open Access Journals (Sweden)

    Shila Gilbert

    2015-02-01

    Full Text Available Intestinal epithelial stem cells (IESCs control the intestinal homeostatic response to inflammation and regeneration. The underlying mechanisms are unclear. Cytokine-STAT5 signaling regulates intestinal epithelial homeostasis and responses to injury. We link STAT5 signaling to IESC replenishment upon injury by depletion or activation of Stat5 transcription factor. We found that depletion of Stat5 led to deregulation of IESC marker expression and decreased LGR5+ IESC proliferation. STAT5-deficient mice exhibited worse intestinal histology and impaired crypt regeneration after γ-irradiation. We generated a transgenic mouse model with inducible expression of constitutively active Stat5. In contrast to Stat5 depletion, activation of STAT5 increased IESC proliferation, accelerated crypt regeneration, and conferred resistance to intestinal injury. Furthermore, ectopic activation of STAT5 in mouse or human stem cells promoted LGR5+ IESC self-renewal. Accordingly, STAT5 promotes IESC proliferation and regeneration to mitigate intestinal inflammation. STAT5 is a functional therapeutic target to improve the IESC regenerative response to gut injury.

  3. Plasticity of intestinal epithelial cells in regeneration and cancer

    NARCIS (Netherlands)

    Tetteh, Paul W.

    2015-01-01

    Cellular plasticity refers to the ability of a cell to change its fate or identity in response to external or intrinsic factors. Regeneration of the intestinal epithelium after injury is driven mainly by plasticity of crypt stem cells that can rapidly divide to replace all the lost cells. Stem cell

  4. n-Butyrate inhibits Jun NH(2)-terminal kinase activation and cytokine transcription in mast cells

    International Nuclear Information System (INIS)

    Diakos, Christos; Prieschl, Eva E.; Saeemann, Marcus D.; Boehmig, Georg A.; Csonga, Robert; Sobanov, Yury; Baumruker, Thomas; Zlabinger, Gerhard J.

    2006-01-01

    Mast cells are well known to contribute to type I allergic conditions but only recently have been brought in association with chronic relapsing/remitting autoimmune diseases such as celiac disease and ulcerative colitis. Since the bacterial metabolite n-butyrate is considered to counteract intestinal inflammation we investigated the effects of this short chain fatty acid on mast cell activation. Using RNAse protection assays and reporter gene technology we show that n-butyrate downregulates TNF-α transcription. This correlates with an impaired activation of the Jun NH(2)-terminal kinase (JNK) but not other MAP kinases such as ERK and p38 that are largely unaffected by n-butyrate. As a consequence, we observed a decreased nuclear activity of AP-1 and NF-AT transcription factors. These results indicate that n-butyrate inhibits critical inflammatory mediators in mast cells by relatively selectively targeting the JNK signalling

  5. Centrosome/Cell cycle uncoupling and elimination in the endoreduplicating intestinal cells of C. elegans.

    Directory of Open Access Journals (Sweden)

    Yu Lu

    Full Text Available The centrosome cycle is most often coordinated with mitotic cell division through the activity of various essential cell cycle regulators, consequently ensuring that the centriole is duplicated once, and only once, per cell cycle. However, this coupling can be altered in specific developmental contexts; for example, multi-ciliated cells generate hundreds of centrioles without any S-phase requirement for their biogenesis, while Drosophila follicle cells eliminate their centrosomes as they begin to endoreduplicate. In order to better understand how the centrosome cycle and the cell cycle are coordinated in a developmental context we use the endoreduplicating intestinal cell lineage of C. elegans to address how novel variations of the cell cycle impact this important process. In C. elegans, the larval intestinal cells undergo one nuclear division without subsequent cytokinesis, followed by four endocycles that are characterized by successive rounds of S-phase. We monitored the levels of centriolar/centrosomal markers and found that centrosomes lose their pericentriolar material following the nuclear division that occurs during the L1 stage and is thereafter never re-gained. The centrioles then become refractory to S phase regulators that would normally promote duplication during the first endocycle, after which they are eliminated during the L2 stage. Furthermore, we show that SPD-2 plays a central role in the numeral regulation of centrioles as a potential target of CDK activity. On the other hand, the phosphorylation on SPD-2 by Polo-like kinase, the transcriptional regulation of genes that affect centriole biogenesis, and the ubiquitin/proteasome degradation pathway, contribute collectively to the final elimination of the centrioles during the L2 stage.

  6. Intestinal stem cells in the adult Drosophila midgut

    International Nuclear Information System (INIS)

    Jiang, Huaqi; Edgar, Bruce A.

    2011-01-01

    Drosophila has long been an excellent model organism for studying stem cell biology. Notably, studies of Drosophila's germline stem cells have been instrumental in developing the stem cell niche concept. The recent discovery of somatic stem cells in adult Drosophila, particularly the intestinal stem cells (ISCs) of the midgut, has established Drosophila as an exciting model to study stem cell-mediated adult tissue homeostasis and regeneration. Here, we review the major signaling pathways that regulate the self-renewal, proliferation and differentiation of Drosophila ISCs, discussing how this regulation maintains midgut homeostasis and mediates regeneration of the intestinal epithelium after injury. -- Highlights: ► The homeostasis and regeneration of adult fly midguts are mediated by ISCs. ► Damaged enterocytes induce the proliferation of intestinal stem cells (ISC). ► EGFR and Jak/Stat signalings mediate compensatory ISC proliferation. ► Notch signaling regulates ISC self-renewal and differentiation.

  7. Tropomyosin Receptor Kinase A Expression on Merkel Cell Carcinoma Cells.

    Science.gov (United States)

    Wehkamp, Ulrike; Stern, Sophie; Krüger, Sandra; Hauschild, Axel; Röcken, Christoph; Egberts, Friederike

    2017-11-01

    Merkel cell carcinoma (MCC) is a malignant neuroendocrine skin tumor frequently associated with the Merkel cell polyomavirus. Immune checkpoint therapy showed remarkable results, although not all patients are responsive to this therapy. Anti-tropomyosin receptor kinase A (TrkA)-targeted treatment has shown promising results in several tumor entities. To determine TrkA expression in MCC as a rationale for potential targeted therapy. This case series study investigated the MCC specimens of 55 patients treated at the Department of Dermatology, University Hospital of Schleswig-Holstein, Kiel, Germany, from January 1, 2005, through December 31, 2015. Thirty-nine of the 55 samples were suitable for further histopathologic examination. Expression of TrkA was explored by immunohistochemical analysis. Diagnosis of MCC was confirmed by staining positive for cytokeratin 20 (CK20) and synaptophysin. Expression of TrkA on the tumor cells. Specimens of 39 patients (21 women and 18 men; mean [SD] age, 75.0 [7.8] years) underwent immunohistochemical investigation. Thirty-eight of 38 specimens expressed CK20 and synaptophysin on the MCC tumor cells (100% expression). Merkel cell polyomavirus was detected in 32 of 38 specimens (84%). Tropomyosin receptor kinase A was found in all 36 evaluable specimens on the tumor cells; 34 (94%) showed a weak and 2 (6%) showed a strong cytoplasmic expression. In addition, strongly positive perinuclear dots were observed in 30 of 36 specimens (83%). Tropomyosin receptor kinase A was expressed on MCC tumor cells in 100% of evaluable specimens. This result may lead to the exploration of new targeted treatment options in MCC, especially for patients who do not respond to anti-programmed cell death protein 1 treatment.

  8. GATA4 Regulates Epithelial Cell Proliferation to Control Intestinal Growth and Development in MiceSummary

    Directory of Open Access Journals (Sweden)

    Bridget M. Kohlnhofer

    2016-03-01

    Full Text Available Background & Aims: The embryonic small intestinal epithelium is highly proliferative, and although much is known about mechanisms regulating proliferation in the adult intestine, the mechanisms controlling epithelial cell proliferation in the developing intestine are less clear. GATA4, a transcription factor that regulates proliferation in other developing tissues, is first expressed early in the developing gut in midgut endoderm. GATA4 function within midgut endoderm and the early intestinal epithelium is unknown. Methods: By using Sonic Hedgehog Cre to eliminate GATA4 in the midgut endoderm of mouse embryos, we determined the impact of loss of GATA4 on intestinal development, including epithelial cell proliferation, between embryonic day (E9.5 and E18.5. Results: We found that intestinal length and width were decreased in GATA4 mutants compared with controls. GATA4-deficient intestinal epithelium contained fewer cells, and epithelial girth was decreased. We further observed a decreased proportion of proliferating epithelial cells at E10.5 and E11.5 in GATA4 mutants. We showed that GATA4 binds to chromatin containing GATA4 consensus binding sites within cyclin D2 (Ccnd2, cyclin-dependent kinase 6 (Cdk6, and frizzled 5 (Fzd5. Moreover, Ccnd2, Cdk6, and Fzd5 transcripts were reduced at E11.5 in GATA4 mutant tissue. Villus morphogenesis was delayed, and villus structure was abnormal in GATA4 mutant intestine. Conclusions: Our data identify GATA4 as an essential regulator of early intestinal epithelial cell proliferation. We propose that GATA4 controls proliferation in part by directly regulating transcription of cell-cycle mediators. Our data further suggest that GATA4 affects proliferation through transcriptional regulation of Fzd5, perhaps by influencing the response of the epithelium to WNT signaling. Keywords: Transcriptional Regulation, WNT Signaling, Villus Morphogenesis

  9. Epithelial Cell Inflammasomes in Intestinal Immunity and Inflammation

    Directory of Open Access Journals (Sweden)

    Andrea C. Lei-Leston

    2017-09-01

    Full Text Available Pattern recognition receptors (PRR, such as NOD-like receptors (NLRs, sense conserved microbial signatures, and host danger signals leading to the coordination of appropriate immune responses. Upon activation, a subset of NLR initiate the assembly of a multimeric protein complex known as the inflammasome, which processes pro-inflammatory cytokines and mediates a specialized form of cell death known as pyroptosis. The identification of inflammasome-associated genes as inflammatory bowel disease susceptibility genes implicates a role for the inflammasome in intestinal inflammation. Despite the fact that the functional importance of inflammasomes within immune cells has been well established, the contribution of inflammasome expression in non-hematopoietic cells remains comparatively understudied. Given that intestinal epithelial cells (IEC act as a barrier between the host and the intestinal microbiota, inflammasome expression by these cells is likely important for intestinal immune homeostasis. Accumulating evidence suggests that the inflammasome plays a key role in shaping epithelial responses at the host–lumen interface with many inflammasome components highly expressed by IEC. Recent studies have exposed functional roles of IEC inflammasomes in mucosal immune defense, inflammation, and tumorigenesis. In this review, we present the main features of the predominant inflammasomes and their effector mechanisms contributing to intestinal homeostasis and inflammation. We also discuss existing controversies in the field and open questions related to their implications in disease. A comprehensive understanding of the molecular basis of intestinal inflammasome signaling could hold therapeutic potential for clinical translation.

  10. Synthesis of protein in intestinal cells exposed to cholera toxin

    International Nuclear Information System (INIS)

    Peterson, J.W.; Berg, W.D. Jr.; Coppenhaver, D.H.

    1987-01-01

    The mechanism by which cyclic adenosine monophosphate (AMP), formed by intestinal epithelial cells in response to cholera toxin, ultimately results in alterations in water and electrolyte transport is poorly understood. Several studies have indicated that inhibitors of transcription or translation block much of the transport of ions and water in the intestine and edema formation in tissue elicited by cholera toxin. Data presented in this study confirmed the inhibitory effects of cycloheximide on cholera toxin-induced fluid accumulation in the rabbit intestinal loop model. Neither cycloheximide nor actinomycin D altered the amount of cyclic AMP that accumulated in intestinal cells and Chinese hamster ovary cells exposed to cholera toxin. An increase in [ 3 H] leucine incorporation was readily demonstrable in intestinal epithelial cells from rabbits challenged with Vibrio cholerae. Similarly, intestinal epithelial cells incubated with cholera toxin for 4 hr synthesized substantially more protein than controls as determined by relative incorporation of [ 35 S] methionine. Most of the new protein synthesized in response to cholera toxin was membrane associated and of high molecular weight. The possible significance of the toxin-induced protein relative to cholera pathogenesis was discussed

  11. Interstitial cells of Cajal in human small intestine. Ultrastructural identification and organization between the main smooth muscle layers

    DEFF Research Database (Denmark)

    Rumessen, Jüri Johannes; Thuneberg, Lars

    1991-01-01

    Anatomy, interstitial cells of Cajal, small intestine, gut motility, pacemaker cells, smooth muscle......Anatomy, interstitial cells of Cajal, small intestine, gut motility, pacemaker cells, smooth muscle...

  12. Very late onset small intestinal B cell lymphoma associated with primary intestinal lymphangiectasia and diffuse cutaneous warts

    OpenAIRE

    Bouhnik, Y; Etienney, I; Nemeth, J; Thevenot, T; Lavergne-Slove, A; Matuchansky, C

    2000-01-01

    As only a handful of lymphoma cases have been reported in conjunction with primary intestinal lymphangiectasia, it is not yet clear if this association is merely fortuitous or related to primary intestinal lymphangiectasia induced immune deficiency. We report on two female patients, 50 and 58 years old, who developed small intestinal high grade B cell lymphoma a long time (45 and 40 years, respectively) after the initial clinical manifestations of primary intestinal lymphangiectasia. They pre...

  13. BVES Regulates Intestinal Stem Cell Programs and Intestinal Crypt Viability after Radiation

    Science.gov (United States)

    Reddy, Vishruth K.; Short, Sarah P.; Barrett, Caitlyn W.; Mittal, Mukul K.; Keating, Cody E.; Thompson, Joshua J.; Harris, Elizabeth I.; Revetta, Frank; Bader, David M.; Brand, Thomas; Washington, M. Kay; Williams, Christopher S.

    2016-01-01

    Blood Vessel Epicardial Substance (BVES/Popdc1) is a junctional-associated transmembrane protein that is underexpressed in a number of malignancies and regulates epithelial-to-mesenchymal transition. We previously identified a role for BVES in regulation of the Wnt pathway, a modulator of intestinal stem cell programs, but its role in small intestinal (SI) biology remains unexplored. We hypothesized that BVES influences intestinal stem cell programs and is critical to SI homeostasis after radiation injury. At baseline, Bves−/− mice demonstrated increased crypt height, as well as elevated proliferation and expression of the stem cell marker Lgr5 compared to wildtype (WT) mice. Intercross with Lgr5-EGFP reporter mice confirmed expansion of the stem cell compartment in Bves−/− mice. To examine stem cell function after BVES deletion, we employed ex vivo 3D-enteroid cultures. Bves−/− enteroids demonstrated increased stemness compared to WT, when examining parameters such as plating efficiency, stem spheroid formation, and retention of peripheral cystic structures. Furthermore, we observed increased proliferation, expression of crypt-base columnar “CBC” and “+4” stem cell markers, amplified Wnt signaling, and responsiveness to Wnt activation in the Bves−/− enteroids. Bves expression was downregulated after radiation in WT mice. Moreover, after radiation, Bves−/− mice demonstrated significantly greater small intestinal crypt viability, proliferation, and amplified Wnt signaling in comparison to WT mice. Bves−/− mice also demonstrated elevations in Lgr5 and Ascl2 expression, and putative damage-responsive stem cell populations marked by Bmi1 and TERT. Therefore, BVES is a key regulator of intestinal stem cell programs and mucosal homeostasis. PMID:26891025

  14. Expression of Plant Receptor Kinases in Tobacco BY-2 Cells.

    Science.gov (United States)

    Shinohara, Hidefumi; Matsubayashi, Yoshikatsu

    2017-01-01

    Although more than 600 single-transmembrane receptor kinase genes have been found in the Arabidopsis genome, only a few of them have known physiological functions, and even fewer plant receptor kinases have known specific ligands. Ligand-binding analysis must be operated using the functionally expressed receptor form. However, the relative abundance of native receptor kinase molecules in the plasma membrane is often quite low. Here, we present a method for stable and functional expression of plant receptor kinases in tobacco BY-2 cells that allows preparation of microsomal fractions containing the receptor. This procedure provides a sufficient amount of receptor proteins while maintaining its ligand-binding activities.

  15. Occurrence of lymphoid cells in the intestine of the Goldfish

    NARCIS (Netherlands)

    Weinberg, Steven

    1975-01-01

    The Goldfish intestine normally contains a large number of lymphocytes, many of them being present in the epithelial layer. After stimulation with antigen, the number of lymphoid cells does not increase, but the proportion of large pyroninophilic cells and plasma cells does. It seems therefore that

  16. How protein kinases co-ordinate mitosis in animal cells.

    Science.gov (United States)

    Ma, Hoi Tang; Poon, Randy Y C

    2011-04-01

    Mitosis is associated with profound changes in cell physiology and a spectacular surge in protein phosphorylation. To accomplish these, a remarkably large portion of the kinome is involved in the process. In the present review, we will focus on classic mitotic kinases, such as cyclin-dependent kinases, Polo-like kinases and Aurora kinases, as well as more recently characterized players such as NIMA (never in mitosis in Aspergillus nidulans)-related kinases, Greatwall and Haspin. Together, these kinases co-ordinate the proper timing and fidelity of processes including centrosomal functions, spindle assembly and microtubule-kinetochore attachment, as well as sister chromatid separation and cytokinesis. A recurrent theme of the mitotic kinase network is the prevalence of elaborated feedback loops that ensure bistable conditions. Sequential phosphorylation and priming phosphorylation on substrates are also frequently employed. Another important concept is the role of scaffolds, such as centrosomes for protein kinases during mitosis. Elucidating the entire repertoire of mitotic kinases, their functions, regulation and interactions is critical for our understanding of normal cell growth and in diseases such as cancers.

  17. Intestinal dendritic cells in the regulation of mucosal immunity

    DEFF Research Database (Denmark)

    Bekiaris, Vasileios; Persson, Emma K.; Agace, William Winston

    2014-01-01

    immune cells within the mucosa must suitably respond to maintain intestinal integrity, while also providing the ability to mount effective immune responses to potential pathogens. Dendritic cells (DCs) are sentinel immune cells that play a central role in the initiation and differentiation of adaptive....... The recognition that dietary nutrients and microbial communities in the intestine influence both mucosal and systemic immune cell development and function as well as immune-mediated disease has led to an explosion of literature in mucosal immunology in recent years and a growing interest in the functionality...

  18. Intestinal stromal cells in mucosal immunity and homeostasis.

    Science.gov (United States)

    Owens, B M J; Simmons, A

    2013-03-01

    A growing body of evidence suggests that non-hematopoietic stromal cells of the intestine have multiple roles in immune responses and inflammation at this mucosal site. Despite this, many still consider gut stromal cells as passive structural entities, with past research focused heavily on their roles in fibrosis, tumor progression, and wound healing, rather than their contributions to immune function. In this review, we discuss our current knowledge of stromal cells in intestinal immunity, highlighting the many immunological axes in which stromal cells have a functional role. We also consider emerging data that broaden the potential scope of their contribution to immunity in the gut and argue that these so-called "non-immune" cells are reclassified in light of their diverse contributions to intestinal innate immunity and the maintenance of mucosal homeostasis.

  19. EGFR kinase-dependent and kinase-independent roles in clear cell renal cell carcinoma.

    Science.gov (United States)

    Cossu-Rocca, Paolo; Muroni, Maria R; Sanges, Francesca; Sotgiu, Giovanni; Asunis, Anna; Tanca, Luciana; Onnis, Daniela; Pira, Giovanna; Manca, Alessandra; Dore, Simone; Uras, Maria G; Ena, Sara; De Miglio, Maria R

    2016-01-01

    Epidermal growth factor receptor (EGFR) is associated with progression of many epithelial malignancies and represents a significant therapeutic target. Although clear cell renal cell carcinoma (CCRCC) has been widely investigated for EGFR molecular alterations, genetic evidences of EGFR gene activating mutations and/or gene amplification have been rarely confirmed in the literature. Therefore, until now EGFR-targeted therapies in clinical trials have been demonstrated unsuccessful. New evidence has been given about the interactions between EGFR and the sodium glucose co-transporter-1 (SGLT1) in maintaining the glucose basal intracellular level to favour cancer cell growth and survival; thus a new functional role may be attributed to EGFR, regardless of its kinase activity. To define the role of EGFR in CCRCC an extensive investigation of genetic changes and functional kinase activities was performed in a series of tumors by analyzing the EGFR mutational status and expression profile, together with the protein expression of downstream signaling pathways members. Furthermore, we investigated the co-expression of EGFR and SGLT1 proteins and their relationships with clinic-pathological features in CCRCC. EGFR protein expression was identified in 98.4% of CCRCC. Furthermore, it was described for the first time that SGLT1 is overexpressed in CCRCC (80.9%), and that co-expression with EGFR is appreciable in 79.4% of the tumours. Moreover, the activation of downstream EGFR pathways was found in about 79.4% of SGLT1-positive CCRCCs. The mutational status analysis of EGFR failed to demonstrate mutations on exons 18 to 24 and the presence of EGFR-variantIII (EGFRvIII) in all CCRCCs analyzed. FISH analysis revealed absence of EGFR amplification, and high polysomy of chromosome 7. Finally, the EGFR gene expression profile showed gene overexpression in 38.2% of CCRCCs. Our study contributes to define the complexity of EGFR role in CCRCC, identifying its bivalent kinase

  20. Clinical Implications of Intestinal Stem Cell Markers in Colorectal Cancer

    DEFF Research Database (Denmark)

    Espersen, Maiken Lise Marcker; Olsen, Jesper; Linnemann, Dorte

    2015-01-01

    Colorectal cancer (CRC) still has one of the highest incidence and mortality rate among cancers. Therefore, improved differential diagnostics and personalized treatment are still needed. Several intestinal stem cell markers have been found to be associated with CRC and might have a prognostic...... and predictive significance in CRC patients. This review provides an overview of the intestinal stem cell markers leucine-rich repeat-containing G-protein-coupled receptor 5 (LGR5), B cell–specific Moloney murine leukemia virus insertion site 1 (BMI1), Musashi1 (MSI1), and sex-determining region y-box 9 (SOX9......) and their implications in human CRC. The exact roles of the intestinal stem cell markers in CRC development and progression remain unclear; however, high expression of these stem cell markers have a potential prognostic significance and might be implicated in chemotherapy resistance...

  1. Interpreting heterogeneity in intestinal tuft cell structure and function.

    Science.gov (United States)

    Banerjee, Amrita; McKinley, Eliot T; von Moltke, Jakob; Coffey, Robert J; Lau, Ken S

    2018-05-01

    Intestinal tuft cells are a morphologically unique cell type, best characterized by striking microvilli that form an apical tuft. These cells represent approximately 0.5% of gut epithelial cells depending on location. While they are known to express chemosensory receptors, their function has remained unclear. Recently, numerous groups have revealed startling insights into intestinal tuft cell biology. Here, we review the latest developments in understanding this peculiar cell type's structure and function. Recent advances in volumetric microscopy have begun to elucidate tuft cell ultrastructure with respect to its cellular neighbors. Moreover, single-cell approaches have revealed greater diversity in the tuft cell population than previously appreciated and uncovered novel markers to characterize this heterogeneity. Finally, advanced model systems have revealed tuft cells' roles in mucosal healing and orchestrating type 2 immunity against eukaryotic infection. While much remains unknown about intestinal tuft cells, these critical advances have illuminated the physiological importance of these previously understudied cells and provided experimentally tractable tools to interrogate this rare cell population. Tuft cells act as luminal sensors, linking the luminal microbiome to the host immune system, which may make them a potent clinical target for modulating host response to a variety of acute or chronic immune-driven conditions.

  2. TRAPping telomerase within the intestinal stem cell niche

    OpenAIRE

    Pech, Matthew F; Artandi, Steven E

    2011-01-01

    Recent work from Hans Clevers' lab reveals high telomerase activity and telomere length in dividing LGR5-positive intestinal stem cells. They further report random chromosome segregation and thus challenge the ‘immortal strand' hypothesis at least for this stem cell population.

  3. Bone Marrow Derivation of Interstitial Cells of Cajal in Small Intestine Following Intestinal Injury

    Directory of Open Access Journals (Sweden)

    Dengqun Liu

    2010-01-01

    Full Text Available Interstitial cells of Cajal (ICCs in gastrointestinal tract are specialized cells serving as pacemaker cells. The origin of ICCs is currently not fully characterized. In this work, we aimed to study whether bone marrow-derived cells (BMDCs could contribute to the origin of ICCs in the muscular plexus of small intestine using GFP-C57BL/6 chimeric mice.Engraftment of BMDCs in the intestine was investigated for GFP expression. GFP positive bone marrow mononuclear cells reached a proportion of 95.65%±3.72% at different times in chimerism. Donor-derived cells distributed widely in all the layers of the gastrointestinal tract. There were GFP positive BMDCs in the myenteric plexus, which resembled characteristics of ICCs, including myenteric location, c-Kit positive staining, and ramified morphology. Donor-derived ICCs in the myenteric plexus contributed to a percentage ranging 9.25%±4.9% of all the ICCs in the myenteric plexus. In conclusion, here we described that donor-derived BMDCs might differentiate into gastrointestinal ICCs after radiation injury, which provided an alternative source for the origin of the ICCs in the muscular plexus of adult intestine. These results further identified the plasticity of BMDCs and indicated therapeutic implications of BMDCs for the gastrointestinal dysmotility caused by ICCs disorders.

  4. Radioprotection of intestinal crypt cells by cox-inhibitors

    International Nuclear Information System (INIS)

    Bisnar, Paul O.; Dones, Rosa Angela S.A.; Serna, Paulene-Ver A.; Deocaris, Chester C.; Guttierez, Kalangitan V.; Deocaris, Custer C.

    2006-01-01

    The regulation of tissue homeostasis in the gastrointestinal epithelium after epithelial injury focuses on the prostaglandins(PGs) as its major mediators. The two cyclooxygenase isoforms, cox-1 and cox-2, catalyze synthesis of PGs. Cox-1 is the predominant cyclooxygenase isoform found in the normal intestine. In contrast, cox-2 is present at low levels in normal intestine but is elevated at sites of inflammation, and in adenomas and carcinomas. To study the effects of various commercially-available cox-inhibitors (Ketorolac: cox-1 selective; Celecoxib: cox-2 selective; and Indocid: cox-1/2 non-selective), we determine mouse crypt epithelial cell fate after genotoxic injury with whole-body gamma-ray exposure at 15 Gy. Intestinal tissues of mice treated with cox-2 inhibitors that showed invariable apoptotic event, however, have increased occurrence of regenerating cells. Our results suggest a potential application of cox-2 selective inhibitors as radioprotective agent for normal cells after radiotherapy. (Author)

  5. Putative tyrosine kinases expressed in K-562 human leukemia cells

    International Nuclear Information System (INIS)

    Partanen, J.; Maekelae, T.P.; Lehvaeslaiho, H.; Alitalo, K.; Alitalo, R.

    1990-01-01

    Tyrosine phosphorylation is important in the transmission of growth and differentiation signals; known tyrosine kinases include several oncoproteins and growth factor receptors. Interestingly, some differentiated cell types, such as erythrocytes and platelets contain high amounts of phosphotyrosine. The authors analyzed tyrosine kinases expressed in the K-562 chronic myelogenous leukemia cell line, which has a bipotential erythroid and megakaryoblastoid differentiation capacity. Analysis of 359 polymerase chain reaction-amplified cDNA clones led to the identification of 14 different tyrosine kinase-related sequences (JTK1-14). Two of the clones (JTK2 and JTK4) represent unusual members of the fibroblast growth factor receptor gene family, and the clones JTK5, JTK11, and JTK14 may also belong to the family of receptor tyrosine kinases but lack a close relationship to any known tyrosine kinase. Each of these different genes has its own characteristic expression pattern in K-562 cells and several other human tumor cell lines. In addition, the JTK11 and JTK14 mRNAs are induced during the megakaryoblastoid differentiation of K-562 cells. These tyrosine kinases may have a role in the differentiation of megakaryoblasts or in the physiology of platelets

  6. Homing of immune cells: role in homeostasis and intestinal inflammation.

    Science.gov (United States)

    Hart, Ailsa L; Ng, Siew C; Mann, Elizabeth; Al-Hassi, Hafid Omar; Bernardo, David; Knight, Stella C

    2010-11-01

    Rather like a satellite navigation system directing a vehicle to a particular destination defined by post-code, immune cells have homing molecules or "immune post-codes" enabling them to be recruited to specific organs, such as the intestine or skin. An efficient system would be designed such that the site of entry of an antigen influences the homing of effector T cells back to the appropriate organ. For example, to mount an immune response against an intestinal pathogen, T cells with a propensity to home to the gut to clear the infection would be induced. In health, there is such a sophisticated and finely tuned system in operation, enabling an appropriate balance of immune activity in different anatomical compartments. In disease states such as inflammatory bowel disease (IBD), which is characterized by intestinal inflammation and often an inflammatory process involving other organs such as skin, joints, liver, and eye, there is accumulating evidence that there is malfunction of this immune cell trafficking system. The clinical importance of dysregulated immune cell trafficking in IBD is reflected in recently proven efficacious therapies that target trafficking pathways such as natalizumab, an α4 integrin antibody, and Traficet-EN, a chemokine receptor-9 (CCR9) antagonist. Here we review the mechanisms involved in the homing of immune cells to different tissues, in particular the intestine, and focus on alterations in immune cell homing pathways in IBD. Unraveling the mechanisms underlying the immune post-code system would assist in achieving the goal of tissue-specific immunotherapy.

  7. Kinase Activity Studied in Living Cells Using an Immunoassay

    Science.gov (United States)

    Bavec, Aljos?a

    2014-01-01

    This laboratory exercise demonstrates the use of an immunoassay for studying kinase enzyme activity in living cells. The advantage over the classical method, in which students have to isolate the enzyme from cell material and measure its activity in vitro, is that enzyme activity is modulated and measured in living cells, providing a more…

  8. Enhanced casein kinase II activity in human tumour cell cultures

    DEFF Research Database (Denmark)

    Prowald, K; Fischer, H; Issinger, O G

    1984-01-01

    Casein kinase II (CKII) activity is enhanced as much as 2-3 fold in established and 4-5-fold in transformed human cell lines when compared to that of fibroblasts and primary human tumour cell cultures where CKII activity never exceeded a basic level. The high activity of CKII in transformed cells...

  9. HDAC1 and HDAC2 restrain the intestinal inflammatory response by regulating intestinal epithelial cell differentiation.

    Directory of Open Access Journals (Sweden)

    Naomie Turgeon

    Full Text Available Acetylation and deacetylation of histones and other proteins depends on histone acetyltransferases and histone deacetylases (HDACs activities, leading to either positive or negative gene expression. HDAC inhibitors have uncovered a role for HDACs in proliferation, apoptosis and inflammation. However, little is known of the roles of specific HDACs in intestinal epithelial cells (IEC. We investigated the consequences of ablating both HDAC1 and HDAC2 in murine IECs. Floxed Hdac1 and Hdac2 homozygous mice were crossed with villin-Cre mice. Mice deficient in both IEC HDAC1 and HDAC2 weighed less and survived more than a year. Colon and small intestinal sections were stained with hematoxylin and eosin, or with Alcian blue and Periodic Acid Schiff for goblet cell identification. Tissue sections from mice injected with BrdU for 2 h, 14 h and 48 h were stained with anti-BrdU. To determine intestinal permeability, 4-kDa FITC-labeled dextran was given by gavage for 3 h. Microarray analysis was performed on total colon RNAs. Inflammatory and IEC-specific gene expression was assessed by Western blot or semi-quantitative RT-PCR and qPCR with respectively total colon protein and total colon RNAs. HDAC1 and HDAC2-deficient mice displayed: 1 increased migration and proliferation, with elevated cyclin D1 expression and phosphorylated S6 ribosomal protein, a downstream mTOR target; 2 tissue architecture defects with cell differentiation alterations, correlating with reduction of secretory Paneth and goblet cells in jejunum and goblet cells in colon, increased expression of enterocytic markers such as sucrase-isomaltase in the colon, increased expression of cleaved Notch1 and augmented intestinal permeability; 3 loss of tissue homeostasis, as evidenced by modifications of claudin 3 expression, caspase-3 cleavage and Stat3 phosphorylation; 4 chronic inflammation, as determined by inflammatory molecular expression signatures and altered inflammatory gene expression

  10. Transformation of intestinal stem cells into gastric stem cells on loss of transcription factor Cdx2

    NARCIS (Netherlands)

    Simmini, Salvatore; Bialecka, Monika; Huch, Meritxell; Kester, Lennart; van de Wetering, Marc; Sato, Toshiro; Beck, Felix; van Oudenaarden, Alexander; Clevers, Hans; Deschamps, Jacqueline

    2014-01-01

    The endodermal lining of the adult gastro-intestinal tract harbours stem cells that are responsible for the day-to-day regeneration of the epithelium. Stem cells residing in the pyloric glands of the stomach and in the small intestinal crypts differ in their differentiation programme and in the gene

  11. Fusion of intestinal epithelial cells with bone marrow derived cells is dispensable for tissue homeostasis

    NARCIS (Netherlands)

    de Jong, Joan H.; Rodermond, Hans M.; Zimberlin, Cheryl D.; Lascano, Valeria; de Sousa E Melo, Felipe; Richel, Dick J.; Medema, Jan Paul; Vermeulen, Louis

    2012-01-01

    The epithelial lining of the intestine is characterized by an immense cellular turn-over ascertaining an extensive regenerative capacity. Multiple reports suggest that besides the local intestinal stem cell pool, circulating cells of bone marrow origin (BMDCs) contribute to this process by fusing

  12. Inhibition of mitogen-activated protein kinase kinase, DNA methyltransferase, and transforming growth factor-β promotes differentiation of human induced pluripotent stem cells into enterocytes.

    Science.gov (United States)

    Kodama, Nao; Iwao, Takahiro; Kabeya, Tomoki; Horikawa, Takashi; Niwa, Takuro; Kondo, Yuki; Nakamura, Katsunori; Matsunaga, Tamihide

    2016-06-01

    We previously reported that small-molecule compounds were effective in generating pharmacokinetically functional enterocytes from human induced pluripotent stem (iPS) cells. In this study, to determine whether the compounds promote the differentiation of human iPS cells into enterocytes, we investigated the effects of a combination of mitogen-activated protein kinase kinase (MEK), DNA methyltransferase (DNMT), and transforming growth factor (TGF)-β inhibitors on intestinal differentiation. Human iPS cells cultured on feeder cells were differentiated into endodermal cells by activin A. These endodermal-like cells were then differentiated into intestinal stem cells by fibroblast growth factor 2. Finally, the cells were differentiated into enterocyte cells by epidermal growth factor and small-molecule compounds. After differentiation, mRNA expression levels and drug-metabolizing enzyme activities were measured. The mRNA expression levels of the enterocyte marker sucrase-isomaltase and the major drug-metabolizing enzyme cytochrome P450 (CYP) 3A4 were increased by a combination of MEK, DNMT, and TGF-β inhibitors. The mRNA expression of CYP3A4 was markedly induced by 1α,25-dihydroxyvitamin D3. Metabolic activities of CYP1A1/2, CYP2B6, CYP2C9, CYP2C19, CYP3A4/5, UDP-glucuronosyltransferase, and sulfotransferase were also observed in the differentiated cells. In conclusion, MEK, DNMT, and TGF-β inhibitors can be used to promote the differentiation of human iPS cells into pharmacokinetically functional enterocytes. Copyright © 2016 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

  13. Expression of tyrosine kinase gene in mouse thymic stromal cells

    NARCIS (Netherlands)

    Rinke de Wit, T. F.; Izon, D. J.; Revilla, C.; Oosterwegel, M.; Bakker, A. Q.; van Ewijk, W.; Kruisbeek, A. M.

    1996-01-01

    Amongst the most important signal transduction molecules involved in regulating growth and differentiation are the protein tyrosine kinases (PTK). Since T cell development is a consequence of interactions between thymic stromal cells (TSC) and thymocytes, identification of the PTK in both

  14. Aging effects on intestinal homeostasis associated with expansion and dysfunction of intestinal epithelial stem cells.

    Science.gov (United States)

    Moorefield, Emily C; Andres, Sarah F; Blue, R Eric; Van Landeghem, Laurianne; Mah, Amanda T; Santoro, M Agostina; Ding, Shengli

    2017-08-29

    Intestinal epithelial stem cells (IESCs) are critical to maintain intestinal epithelial function and homeostasis. We tested the hypothesis that aging promotes IESC dysfunction using old (18-22 months) and young (2-4 month) Sox9-EGFP IESC reporter mice. Different levels of Sox9-EGFP permit analyses of active IESC (Sox9-EGFP Low ), activatable reserve IESC and enteroendocrine cells (Sox9-EGFP High ), Sox9-EGFP Sublow progenitors, and Sox9-EGFP Negative differentiated lineages. Crypt-villus morphology, cellular composition and apoptosis were measured by histology. IESC function was assessed by crypt culture, and proliferation by flow cytometry and histology. Main findings were confirmed in Lgr5-EGFP and Lgr5-LacZ mice. Aging-associated gene expression changes were analyzed by Fluidigm mRNA profiling. Crypts culture from old mice yielded fewer and less complex enteroids. Histology revealed increased villus height and Paneth cells per crypt in old mice. Old mice showed increased numbers and hyperproliferation of Sox9-EGFP Low IESC and Sox9-EGFP High cells. Cleaved caspase-3 staining demonstrated increased apoptotic cells in crypts and villi of old mice. Gene expression profiling revealed aging-associated changes in mRNAs associated with cell cycle, oxidative stress and apoptosis specifically in IESC. These findings provide new, direct evidence for aging associated IESC dysfunction, and define potential biomarkers and targets for translational studies to assess and maintain IESC function during aging.

  15. Intestinal stem cells in the adult Drosophila midgut

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Huaqi, E-mail: Huaqi.Jiang@UTSouthwestern.edu [Department of Developmental Biology, UT Southwestern Medical Center, 6000 Harry Hines Blvd., Dallas, TX, 75235 (United States); Edgar, Bruce A., E-mail: b.edgar@dkfz.de [ZMBH-DKFZ Alliance, Im Neuenheimer Feld 282, D-69120 Heidelberg (Germany); Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., Seattle, WA 98109 (United States)

    2011-11-15

    Drosophila has long been an excellent model organism for studying stem cell biology. Notably, studies of Drosophila's germline stem cells have been instrumental in developing the stem cell niche concept. The recent discovery of somatic stem cells in adult Drosophila, particularly the intestinal stem cells (ISCs) of the midgut, has established Drosophila as an exciting model to study stem cell-mediated adult tissue homeostasis and regeneration. Here, we review the major signaling pathways that regulate the self-renewal, proliferation and differentiation of Drosophila ISCs, discussing how this regulation maintains midgut homeostasis and mediates regeneration of the intestinal epithelium after injury. -- Highlights: Black-Right-Pointing-Pointer The homeostasis and regeneration of adult fly midguts are mediated by ISCs. Black-Right-Pointing-Pointer Damaged enterocytes induce the proliferation of intestinal stem cells (ISC). Black-Right-Pointing-Pointer EGFR and Jak/Stat signalings mediate compensatory ISC proliferation. Black-Right-Pointing-Pointer Notch signaling regulates ISC self-renewal and differentiation.

  16. Esterification of xanthophylls by human intestinal Caco-2 cells.

    Science.gov (United States)

    Sugawara, Tatsuya; Yamashita, Kyoko; Asai, Akira; Nagao, Akihiko; Shiraishi, Tomotaka; Imai, Ichiro; Hirata, Takashi

    2009-03-15

    We recently found that peridinin, which is uniquely present in dinoflagellates, reduced cell viability by inducing apoptosis in human colon cancer cells. Peridinin is also found in edible clams and oysters because the major food sources of those shellfish are phytoplanktons such as dinoflagellates. Little is known, however, about the fate of dietary peridinin and its biological activities in mammals. The aim of the present study was to investigate the enzymatic esterification of xanthophylls, especially peridinin which is uniquely present in dinoflagellates, using differentiated cultures of Caco-2 human intestinal cells. We found that peridinin is converted to peridininol and its fatty acid esters in differentiated Caco-2 cells treated with 5mumol/L peridinin solubilized with mixed micelles. The cell homogenate was also able to deacetylate peridinin and to esterify peridininol. Other xanthophylls, such as fucoxanthin, astaxanthin and zeaxanthin, were also esterified, but at relatively lower rates than peridinin. In this study, we found the enzymatic esterification of xanthophylls in mammalian intestinal cells for the first time. Our results suggest that the esterification of xanthophylls in intestinal cells is dependent on their polarity.

  17. File list: Oth.Dig.20.AllAg.Intestinal_stem_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Dig.20.AllAg.Intestinal_stem_cells mm9 TFs and others Digestive tract Intestina...l stem cells SRX856961,SRX1141904,SRX1141903 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.Dig.20.AllAg.Intestinal_stem_cells.bed ...

  18. File list: Unc.Dig.50.AllAg.Intestinal_stem_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Dig.50.AllAg.Intestinal_stem_cells mm9 Unclassified Digestive tract Intestinal ...stem cells http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.Dig.50.AllAg.Intestinal_stem_cells.bed ...

  19. File list: Oth.Dig.10.AllAg.Intestinal_stem_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Dig.10.AllAg.Intestinal_stem_cells mm9 TFs and others Digestive tract Intestina...l stem cells SRX1141904,SRX856961,SRX1141903 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.Dig.10.AllAg.Intestinal_stem_cells.bed ...

  20. Insulin resistance in vascular endothelial cells promotes intestinal tumour formation

    DEFF Research Database (Denmark)

    Wang, X; Häring, M-F; Rathjen, Thomas

    2017-01-01

    in vascular endothelial cells. Strikingly, these mice had 42% more intestinal tumours than controls, no change in tumour angiogenesis, but increased expression of vascular cell adhesion molecule-1 (VCAM-1) in primary culture of tumour endothelial cells. Insulin decreased VCAM-1 expression and leukocyte...... adhesion in quiescent tumour endothelial cells with intact insulin receptors and partly prevented increases in VCAM-1 and leukocyte adhesion after treatment with tumour necrosis factor-α. Knockout of insulin receptors in endothelial cells also increased leukocyte adhesion in mesenteric venules...

  1. Stem cells and cancer of the stomach and intestine.

    Science.gov (United States)

    Vries, Robert G J; Huch, Meritxell; Clevers, Hans

    2010-10-01

    Cancer in the 21st century has become the number one cause of death in developed countries. Although much progress has been made in improving patient survival, tumour relapse is one of the important causes of cancer treatment failure. An early observation in the study of cancer was the heterogeneity of tumours. Traditionally, this was explained by a combination of genomic instability of tumours and micro environmental factors leading to diverse phenotypical characteristics. It was assumed that cells in a tumour have an equal capacity to propagate the cancer. This model is currently known as the stochastic model. Recently, the Cancer stem cell model has been proposed to explain the heterogeneity of a tumour and its progression. According to this model, the heterogeneity of tumours is the result of aberrant differentiation of tumour cells into the cells of the tissue the tumour originated from. Tumours were suggested to contain stem cell-like cells, the cancer stem cells or tumour-initiating cells, which are uniquely capable of propagating a tumour much like normal stem cells fuel proliferation and differentiation in normal tissue. In this review we discuss the normal stem cell biology of the stomach and intestine followed by both the stochastic and cancer stem cell models in light of recent findings in the gastric and intestinal systems. The molecular pathways underlying normal and tumourigenic growth have been well studied, and recently the stem cells of the stomach and intestine have been identified. Furthermore, intestinal stem cells were identified as the cells-of-origin of colon cancer upon loss of the tumour suppressor APC. Lastly, several studies have proposed the positive identification of a cancer stem cell of human colon cancer. At the end we compare the cancer stem cell model and the stochastic model. We conclude that clonal evolution of tumour cells resulting from genetic mutations underlies tumour initiation and progression in both cancer models. This

  2. Intestinal bacteria and the regulation of immune cell homeostasis.

    Science.gov (United States)

    Hill, David A; Artis, David

    2010-01-01

    The human intestine is colonized by an estimated 100 trillion bacteria. Some of these bacteria are essential for normal physiology, whereas others have been implicated in the pathogenesis of multiple inflammatory diseases including IBD and asthma. This review examines the influence of signals from intestinal bacteria on the homeostasis of the mammalian immune system in the context of health and disease. We review the bacterial composition of the mammalian intestine, known bacterial-derived immunoregulatory molecules, and the mammalian innate immune receptors that recognize them. We discuss the influence of bacterial-derived signals on immune cell function and the mechanisms by which these signals modulate the development and progression of inflammatory disease. We conclude with an examination of successes and future challenges in using bacterial communities or their products in the prevention or treatment of human disease.

  3. Differentiation-dependent activation of the human intestinal alkaline phosphatase promoter by HNF-4 in intestinal cells

    DEFF Research Database (Denmark)

    Olsen, Line; Bressendorff, Simon; Troelsen, Jesper T

    2005-01-01

    The intestinal alkaline phosphatase gene (ALPI) encodes a digestive brush-border enzyme, which is highly upregulated during small intestinal epithelial cell differentiation. To identify new putative promoter motifs responsible for the regulation of ALPI expression during differentiation of the en...

  4. Ca2+-dependent localization of integrin-linked kinase to cell junctions in differentiating keratinocytes.

    Science.gov (United States)

    Vespa, Alisa; Darmon, Alison J; Turner, Christopher E; D'Souza, Sudhir J A; Dagnino, Lina

    2003-03-28

    Integrin complexes are necessary for proper proliferation and differentiation of epidermal keratinocytes. Differentiation of these cells is accompanied by down-regulation of integrins and focal adhesions as well as formation of intercellular adherens junctions through E-cadherin homodimerization. A central component of integrin adhesion complexes is integrin-linked kinase (ILK), which can induce loss of E-cadherin expression and epithelial-mesenchymal transformation when ectopically expressed in intestinal and mammary epithelia. In cultured primary mouse keratinocytes, we find that ILK protein levels are independent of integrin expression and signaling, since they remain constant during Ca(2+)-induced differentiation. In contrast, keratinocyte differentiation is accompanied by marked reduction in kinase activity in ILK immunoprecipitates and altered ILK subcellular distribution. Specifically, ILK distributes in close apposition to actin fibers along intercellular junctions in differentiated but not in undifferentiated keratinocytes. ILK localization to cell-cell borders occurs independently of integrin signaling and requires Ca(2+) as well as an intact actin cytoskeleton. Further, and in contrast to what is observed in other epithelial cells, ILK overexpression in differentiated keratinocytes does not promote E-cadherin down-regulation and epithelial-mesenchymal transition. Thus, novel tissue-specific mechanisms control the formation of ILK complexes associated with cell-cell junctions in differentiating murine epidermal keratinocytes.

  5. Phorbol esters alter adenylate cyclase responses to vasoactive intestinal peptide and forskolin in the GH cell line

    Energy Technology Data Exchange (ETDEWEB)

    Summers, S.; Florio, T.; Cronin, M.

    1986-05-01

    Activation of protein kinase C with phorbol ester modifies cyclic AMP production in several anterior pituitary cell systems. In the GH cell line from a rat pituitary tumor, exposure to phorbol 12-myristate 13-acetate (PMA: 100 nM) for 30 minutes significantly reduces vasoactive intestinal peptide (VIP: 100 nM) stimulated adenylate cyclase (AC) activity in subsequent membrane preparations to 62 + 4% of control (n = 6 independent studies). In contrast, these same membrane preparations respond to forskolin (1 ..mu..M) with significantly more activity, 130 +/- 6% of controls (n = 6 independent studies). Finally, phorbol ester does not block an inhibitory hormone input into the AC system; somatostatin (100 nM) reduction of VIP-stimulated AC activity is not significantly different in membrane preparations from PMA treated and control cells (n = 3 independent studies). These other findings lead the authors to propose that protein kinase C can modify several sites in the AC complex in anterior pituitary cells.

  6. Celiac anti-type 2 transglutaminase antibodies induce phosphoproteome modification in intestinal epithelial Caco-2 cells.

    Directory of Open Access Journals (Sweden)

    Gaetana Paolella

    Full Text Available BACKGROUND: Celiac disease is an inflammatory condition of the small intestine that affects genetically predisposed individuals after dietary wheat gliadin ingestion. Type 2-transglutaminase (TG2 activity seems to be responsible for a strong autoimmune response in celiac disease, TG2 being the main autoantigen. Several studies support the concept that celiac anti-TG2 antibodies may contribute to disease pathogenesis. Our recent findings on the ability of anti-TG2 antibodies to induce a rapid intracellular mobilization of calcium ions, as well as extracellular signal-regulated kinase phosphorylation, suggest that they potentially act as signaling molecules. In line with this concept, we have investigated whether anti-TG2 antibodies can induce phosphoproteome modification in an intestinal epithelial cell line. METHODS AND PRINCIPAL FINDINGS: We studied phosphoproteome modification in Caco-2 cells treated with recombinant celiac anti-TG2 antibodies. We performed a two-dimensional electrophoresis followed by specific staining of phosphoproteins and mass spectrometry analysis of differentially phosphorylated proteins. Of 14 identified proteins (excluding two uncharacterized proteins, three were hypophosphorylated and nine were hyperphosphorylated. Bioinformatics analyses confirmed the presence of phosphorylation sites in all the identified proteins and highlighted their involvement in several fundamental biological processes, such as cell cycle progression, cell stress response, cytoskeletal organization and apoptosis. CONCLUSIONS: Identification of differentially phosphorylated proteins downstream of TG2-antibody stimulation suggests that in Caco-2 cells these antibodies perturb cell homeostasis by behaving as signaling molecules. We hypothesize that anti-TG2 autoantibodies may destabilize the integrity of the intestinal mucosa in celiac individuals, thus contributing to celiac disease establishment and progression. Since several proteins here

  7. IRF8 dependent classical dendritic cells are essential for intestinal T cell homeostasis

    DEFF Research Database (Denmark)

    Luda, K.; Joeris, Thorsten; Persson, E. K.

    2016-01-01

    The role of dendritic cells (DCs) in intestinal immune homeostasis remains incompletely defined. Here we show that mice lacking IRF8 dependent DCs have reduced numbers of T cells in the small intestine (SI), but not large intestine (LI), including an almost complete absence of SI CD8ab+ andCD4+CD8......aa+ T cells; the latter requiring b8 integrin expression by migratory IRF8 dependent CD103+CD11b- DCs. SI homing receptor induction was impaired during T cell priming in mesenteric lymph nodes (MLN), which correlated with a reduction in aldehyde dehydrogenase activity by SI derived MLN DCs......, and inefficient T cell localization to the SI. Finally, mice with a DC deletion in IRF8 lacked intestinal T helper 1 (Th1) cells, and failed to support Th1 cell differentiation in MLN and mount Th1 responses to Trichuris muris infection. Collectively these results highlight multiple non-redundant roles for IRF8...

  8. Dendritic Cells in the Gut: Interaction with Intestinal Helminths

    Directory of Open Access Journals (Sweden)

    Fela Mendlovic

    2010-01-01

    Full Text Available The mucosal environment in mammals is highly tolerogenic; however, after exposure to pathogens or danger signals, it is able to shift towards an inflammatory response. Dendritic cells (DCs orchestrate immune responses and are highly responsible, through the secretion of cytokines and expression of surface markers, for the outcome of such immune response. In particular, the DC subsets found in the intestine have specialized functions and interact with different immune as well as nonimmune cells. Intestinal helminths primarily induce Th2 responses where DCs have an important yet not completely understood role. In addition, this cross-talk results in the induction of regulatory T cells (T regs as a result of the homeostatic mucosal environment. This review highlights the importance of studying the particular relation “helminth-DC-milieu” in view of the significance that each of these factors plays. Elucidating the mechanisms that trigger Th2 responses may provide the understanding of how we might modulate inflammatory processes.

  9. Canine osteosarcoma cells exhibit resistance to aurora kinase inhibitors.

    Science.gov (United States)

    Cannon, C M; Pozniak, J; Scott, M C; Ito, D; Gorden, B H; Graef, A J; Modiano, J F

    2015-03-01

    We evaluated the effect of Aurora kinase inhibitors AZD1152 and VX680 on canine osteosarcoma cells. Cytotoxicity was seen in all four cell lines; however, half-maximal inhibitory concentrations were significantly higher than in human leukaemia and canine lymphoma cells. AZD1152 reduced Aurora kinase B phosphorylation, indicating resistance was not because of failure of target recognition. Efflux mediated by ABCB1 and ABCG2 transporters is one known mechanism of resistance against these drugs and verapamil enhanced AZD1152-induced apoptosis; however, these transporters were only expressed by a small percentage of cells in each line and the effects of verapamil were modest, suggesting other mechanisms contribute to resistance. Our results indicate that canine osteosarcoma cells are resistant to Aurora kinase inhibitors and suggest that these compounds are unlikely to be useful as single agents for this disease. Further investigation of these resistance mechanisms and the potential utility of Aurora kinase inhibitors in multi-agent protocols is warranted. © 2013 Blackwell Publishing Ltd.

  10. Development of Functional Microfold (M Cells from Intestinal Stem Cells in Primary Human Enteroids.

    Directory of Open Access Journals (Sweden)

    Joshua D Rouch

    Full Text Available Intestinal microfold (M cells are specialized epithelial cells that act as gatekeepers of luminal antigens in the intestinal tract. They play a critical role in the intestinal mucosal immune response through transport of viruses, bacteria and other particles and antigens across the epithelium to immune cells within Peyer's patch regions and other mucosal sites. Recent studies in mice have demonstrated that M cells are generated from Lgr5+ intestinal stem cells (ISCs, and that infection with Salmonella enterica serovar Typhimurium increases M cell formation. However, it is not known whether and how these findings apply to primary human small intestinal epithelium propagated in an in vitro setting.Human intestinal crypts were grown as monolayers with growth factors and treated with recombinant RANKL, and assessed for mRNA transcripts, immunofluorescence and uptake of microparticles and S. Typhimurium.Functional M cells were generated by short-term culture of freshly isolated human intestinal crypts in a dose- and time-dependent fashion. RANKL stimulation of the monolayer cultures caused dramatic induction of the M cell-specific markers, SPIB, and Glycoprotein-2 (GP2 in a process primed by canonical WNT signaling. Confocal microscopy demonstrated a pseudopod phenotype of GP2-positive M cells that preferentially take up microparticles. Furthermore, infection of the M cell-enriched cultures with the M cell-tropic enteric pathogen, S. Typhimurium, led to preferential association of the bacteria with M cells, particularly at lower inoculum sizes. Larger inocula caused rapid induction of M cells.Human intestinal crypts containing ISCs can be cultured and differentiate into an epithelial layer with functional M cells with characteristic morphological and functional properties. This study is the first to demonstrate that M cells can be induced to form from primary human intestinal epithelium, and that S. Typhimurium preferentially infect these cells in an

  11. Foxl1-Expressing Mesenchymal Cells Constitute the Intestinal Stem Cell NicheSummary

    Directory of Open Access Journals (Sweden)

    Reina Aoki

    2016-03-01

    Full Text Available Background & Aims: Intestinal epithelial stem cells that express leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5 and/or B cell specific Moloney murine leukemia virus integration site 1 (Bmi1 continuously replicate and generate differentiated cells throughout life. Previously, Paneth cells were suggested to constitute an epithelium-intrinsic niche that regulates the behavior of these stem cells. However, ablating Paneth cells has no effect on the maintenance of functional stem cells. Here, we show definitively that a small subset of mesenchymal subepithelial cells expressing the winged-helix transcription factor forkhead box l1 (Foxl1 are a critical component of the intestinal stem cell niche. Methods: We genetically ablated Foxl1+ mesenchymal cells in adult mice using 2 separate models by expressing either the human or simian diphtheria toxin receptor under Foxl1 promoter control. Conclusions: Killing Foxl1+ cells by diphtheria toxin administration led to an abrupt cessation of proliferation of both epithelial stem- and transit-amplifying progenitor cell populations that was associated with a loss of active Wnt signaling to the intestinal epithelium. Therefore, Foxl1-expressing mesenchymal cells constitute the fundamental niche for intestinal stem cells. Keywords: Intestinal Stem Cell Niche, Wnt, Mesenchyme

  12. Concise review: the yin and yang of intestinal (cancer) stem cells and their progenitors

    NARCIS (Netherlands)

    Stange, D.E.; Clevers, H.

    2013-01-01

    The intestine has developed over the last few years into a prime model system for adult stem cell research. Intestinal cells have an average lifetime of 5 days, moving within this time from the bottom of intestinal crypts to the top of villi. This rapid self-renewal capacity combined with an easy to

  13. An Arabidopsis kinase cascade influences auxin-responsive cell expansion.

    Science.gov (United States)

    Enders, Tara A; Frick, Elizabeth M; Strader, Lucia C

    2017-10-01

    Mitogen-activated protein kinase (MPK) cascades are conserved mechanisms of signal transduction across eukaryotes. Despite the importance of MPK proteins in signaling events, specific roles for many Arabidopsis MPK proteins remain unknown. Multiple studies have suggested roles for MPK signaling in a variety of auxin-related processes. To identify MPK proteins with roles in auxin response, we screened mpk insertional alleles and identified mpk1-1 as a mutant that displays hypersensitivity in auxin-responsive cell expansion assays. Further, mutants defective in the upstream MAP kinase kinase MKK3 also display hypersensitivity in auxin-responsive cell expansion assays, suggesting that this MPK cascade affects auxin-influenced cell expansion. We found that MPK1 interacts with and phosphorylates ROP BINDING PROTEIN KINASE 1 (RBK1), a protein kinase that interacts with members of the Rho-like GTPases from Plants (ROP) small GTPase family. Similar to mpk1-1 and mkk3-1 mutants, rbk1 insertional mutants display auxin hypersensitivity, consistent with a possible role for RBK1 downstream of MPK1 in influencing auxin-responsive cell expansion. We found that RBK1 directly phosphorylates ROP4 and ROP6, supporting the possibility that RBK1 effects on auxin-responsive cell expansion are mediated through phosphorylation-dependent modulation of ROP activity. Our data suggest a MKK3 • MPK1 • RBK1 phosphorylation cascade that may provide a dynamic module for altering cell expansion. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  14. Intestinal Microbiota and Relapse After Hematopoietic-Cell Transplantation.

    Science.gov (United States)

    Peled, Jonathan U; Devlin, Sean M; Staffas, Anna; Lumish, Melissa; Khanin, Raya; Littmann, Eric R; Ling, Lilan; Kosuri, Satyajit; Maloy, Molly; Slingerland, John B; Ahr, Katya F; Porosnicu Rodriguez, Kori A; Shono, Yusuke; Slingerland, Ann E; Docampo, Melissa D; Sung, Anthony D; Weber, Daniela; Alousi, Amin M; Gyurkocza, Boglarka; Ponce, Doris M; Barker, Juliet N; Perales, Miguel-Angel; Giralt, Sergio A; Taur, Ying; Pamer, Eric G; Jenq, Robert R; van den Brink, Marcel R M

    2017-05-20

    Purpose The major causes of mortality after allogeneic hematopoietic-cell transplantation (allo-HCT) are relapse, graft-versus-host disease (GVHD), and infection. We have reported previously that alterations in the intestinal flora are associated with GVHD, bacteremia, and reduced overall survival after allo-HCT. Because intestinal bacteria are potent modulators of systemic immune responses, including antitumor effects, we hypothesized that components of the intestinal flora could be associated with relapse after allo-HCT. Methods The intestinal microbiota of 541 patients admitted for allo-HCT was profiled by means of 16S ribosomal sequencing of prospectively collected stool samples. We examined the relationship between abundance of microbiota species or groups of related species and relapse/progression of disease during 2 years of follow-up time after allo-HCT by using cause-specific proportional hazards in a retrospective discovery-validation cohort study. Results Higher abundance of a bacterial group composed mostly of Eubacterium limosum in the validation set was associated with a decreased risk of relapse/progression of disease (hazard ratio [HR], 0.82 per 10-fold increase in abundance; 95% CI, 0.71 to 0.95; P = .009). When the patients were categorized according to presence or absence of this bacterial group, presence also was associated with less relapse/progression of disease (HR, 0.52; 95% CI, 0.31 to 0.87; P = .01). The 2-year cumulative incidences of relapse/progression among patients with and without this group of bacteria were 19.8% and 33.8%, respectively. These associations remained significant in multivariable models and were strongest among recipients of T-cell-replete allografts. Conclusion We found associations between the abundance of a group of bacteria in the intestinal flora and relapse/progression of disease after allo-HCT. These might serve as potential biomarkers or therapeutic targets to prevent relapse and improve survival after allo-HCT.

  15. Ret receptor tyrosine kinase sustains proliferation and tissue maturation in intestinal epithelia

    DEFF Research Database (Denmark)

    Perea, Daniel; Guiu, Jordi; Hudry, Bruno

    2017-01-01

    Expression of the Ret receptor tyrosine kinase is a defining feature of enteric neurons. Its importance is underscored by the effects of its mutation in Hirschsprung disease, leading to absence of gut innervation and severe gastrointestinal symptoms. We report a new and physiologically significant...

  16. Adult zebrafish intestine resection: a novel model of short bowel syndrome, adaptation, and intestinal stem cell regeneration.

    Science.gov (United States)

    Schall, K A; Holoyda, K A; Grant, C N; Levin, D E; Torres, E R; Maxwell, A; Pollack, H A; Moats, R A; Frey, M R; Darehzereshki, A; Al Alam, D; Lien, C; Grikscheit, T C

    2015-08-01

    Loss of significant intestinal length from congenital anomaly or disease may lead to short bowel syndrome (SBS); intestinal failure may be partially offset by a gain in epithelial surface area, termed adaptation. Current in vivo models of SBS are costly and technically challenging. Operative times and survival rates have slowed extension to transgenic models. We created a new reproducible in vivo model of SBS in zebrafish, a tractable vertebrate model, to facilitate investigation of the mechanisms of intestinal adaptation. Proximal intestinal diversion at segment 1 (S1, equivalent to jejunum) was performed in adult male zebrafish. SBS fish emptied distal intestinal contents via stoma as in the human disease. After 2 wk, S1 was dilated compared with controls and villus ridges had increased complexity, contributing to greater villus epithelial perimeter. The number of intervillus pockets, the intestinal stem cell zone of the zebrafish increased and contained a higher number of bromodeoxyuridine (BrdU)-labeled cells after 2 wk of SBS. Egf receptor and a subset of its ligands, also drivers of adaptation, were upregulated in SBS fish. Igf has been reported as a driver of intestinal adaptation in other animal models, and SBS fish exposed to a pharmacological inhibitor of the Igf receptor failed to demonstrate signs of intestinal adaptation, such as increased inner epithelial perimeter and BrdU incorporation. We describe a technically feasible model of human SBS in the zebrafish, a faster and less expensive tool to investigate intestinal stem cell plasticity as well as the mechanisms that drive intestinal adaptation. Copyright © 2015 the American Physiological Society.

  17. The Inside Story of Shigella Invasion of Intestinal Epithelial Cells

    Science.gov (United States)

    Carayol, Nathalie; Tran Van Nhieu, Guy

    2013-01-01

    As opposed to other invasive pathogens that reside into host cells in a parasitic mode, Shigella, the causative agent of bacillary dysentery, invades the colonic mucosa but does not penetrate further to survive into deeper tissues. Instead, Shigella invades, replicates, and disseminates within the colonic mucosa. Bacterial invasion and spreading in intestinal epithelium lead to the elicitation of inflammatory responses responsible for the tissue destruction and shedding in the environment for further infection of other hosts. In this article, we highlight specific features of the Shigella arsenal of virulence determinants injected by a type III secretion apparatus (T3SA) that point to the targeting of intestinal epithelial cells as a discrete route of invasion during the initial event of the infectious process. PMID:24086068

  18. Sphingosine kinase-1 mediates androgen-induced osteoblast cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Claire [CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse F-31000 (France); Universite de Toulouse, UPS, IPBS, Toulouse F-31000 (France); Lafosse, Jean-Michel [CHU Toulouse, Hopital Rangueil, Service d' orthopedie et Traumatologie, Toulouse F-31000 (France); Malavaud, Bernard [CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse F-31000 (France); Universite de Toulouse, UPS, IPBS, Toulouse F-31000 (France); CHU Toulouse, Hopital Rangueil, Service d' Urologie et de Transplantation Renale, Toulouse F-31000 (France); Cuvillier, Olivier, E-mail: olivier.cuvillier@ipbs.fr [CNRS, Institut de Pharmacologie et de Biologie Structurale, Toulouse F-31000 (France); Universite de Toulouse, UPS, IPBS, Toulouse F-31000 (France)

    2010-01-01

    Herein we report that the lipid kinase sphingosine kinase-1 (SphK1) is instrumental in mediating androgen-induced cell proliferation in osteoblasts. Dihydrotestosterone (DHT) triggered cell growth in steroid-deprived MC3T3 cells, which was associated with a rapid stimulation of SphK1 and activation of both Akt and ERK signaling pathways. This mechanism relied on functional androgen receptor/PI3K/Akt nongenotropic signaling as pharmacological antagonists could block SphK1 stimulation by DHT and its consequences. Finally, SphK1 inhibition not only abrogated DHT-induced ERK activation but also blocked cell proliferation, while ERK inhibition had no impact, suggesting that SphK1 was critical for DHT signaling yet independently of the ERK.

  19. Gliadin, zonulin and gut permeability: Effects on celiac and non-celiac intestinal mucosa and intestinal cell lines.

    Science.gov (United States)

    Drago, Sandro; El Asmar, Ramzi; Di Pierro, Mariarosaria; Grazia Clemente, Maria; Tripathi, Amit; Sapone, Anna; Thakar, Manjusha; Iacono, Giuseppe; Carroccio, Antonio; D'Agate, Cinzia; Not, Tarcisio; Zampini, Lucia; Catassi, Carlo; Fasano, Alessio

    2006-04-01

    Little is known about the interaction of gliadin with intestinal epithelial cells and the mechanism(s) through which gliadin crosses the intestinal epithelial barrier. We investigated whether gliadin has any immediate effect on zonulin release and signaling. Both ex vivo human small intestines and intestinal cell monolayers were exposed to gliadin, and zonulin release and changes in paracellular permeability were monitored in the presence and absence of zonulin antagonism. Zonulin binding, cytoskeletal rearrangement, and zonula occludens-1 (ZO-1) redistribution were evaluated by immunofluorescence microscopy. Tight junction occludin and ZO-1 gene expression was evaluated by real-time polymerase chain reaction (PCR). When exposed to gliadin, zonulin receptor-positive IEC6 and Caco2 cells released zonulin in the cell medium with subsequent zonulin binding to the cell surface, rearrangement of the cell cytoskeleton, loss of occludin-ZO1 protein-protein interaction, and increased monolayer permeability. Pretreatment with the zonulin antagonist FZI/0 blocked these changes without affecting zonulin release. When exposed to luminal gliadin, intestinal biopsies from celiac patients in remission expressed a sustained luminal zonulin release and increase in intestinal permeability that was blocked by FZI/0 pretreatment. Conversely, biopsies from non-celiac patients demonstrated a limited, transient zonulin release which was paralleled by an increase in intestinal permeability that never reached the level of permeability seen in celiac disease (CD) tissues. Chronic gliadin exposure caused down-regulation of both ZO-1 and occludin gene expression. Based on our results, we concluded that gliadin activates zonulin signaling irrespective of the genetic expression of autoimmunity, leading to increased intestinal permeability to macromolecules.

  20. Selective sparing of goblet cells and paneth cells in the intestine of methotrexate-treated rats

    NARCIS (Netherlands)

    M. Verburg (Melissa); I.B. Renes (Ingrid); H.P. Meijer; J.A. Taminiau; H.A. Büller (Hans); A.W.C. Einerhand (Sandra); J. Dekker (Jan)

    2000-01-01

    textabstractProliferation, differentiation, and cell death were studied in small intestinal and colonic epithelia of rats after treatment with methotrexate. Days 1-2 after treatment were characterized by decreased proliferation, increased apoptosis, and decreased numbers and depths

  1. BMP signaling inhibits intestinal stem cell self-renewal through suppression of Wnt-beta-catenin signaling.

    Science.gov (United States)

    He, Xi C; Zhang, Jiwang; Tong, Wei-Gang; Tawfik, Ossama; Ross, Jason; Scoville, David H; Tian, Qiang; Zeng, Xin; He, Xi; Wiedemann, Leanne M; Mishina, Yuji; Li, Linheng

    2004-10-01

    In humans, mutations in BMPR1A, SMAD4 and PTEN are responsible for juvenile polyposis syndrome, juvenile intestinal polyposis and Cowden disease, respectively. The development of polyposis is a common feature of these diseases, suggesting that there is an association between BMP and PTEN pathways. The mechanistic link between BMP and PTEN pathways and the related etiology of juvenile polyposis is unresolved. Here we show that conditional inactivation of Bmpr1a in mice disturbs homeostasis of intestinal epithelial regeneration with an expansion of the stem and progenitor cell populations, eventually leading to intestinal polyposis resembling human juvenile polyposis syndrome. We show that BMP signaling suppresses Wnt signaling to ensure a balanced control of stem cell self-renewal. Mechanistically, PTEN, through phosphatidylinosital-3 kinase-Akt, mediates the convergence of the BMP and Wnt pathways on control of beta-catenin. Thus, BMP signaling may control the duplication of intestinal stem cells, thereby preventing crypt fission and the subsequent increase in crypt number.

  2. Small intestinal eosinophils regulate Th17 cells by producing IL-1 receptor antagonist.

    Science.gov (United States)

    Sugawara, Reiko; Lee, Eun-Jung; Jang, Min Seong; Jeun, Eun-Ji; Hong, Chun-Pyo; Kim, Jung-Hwan; Park, Areum; Yun, Chang Ho; Hong, Sung-Wook; Kim, You-Me; Seoh, Ju-Young; Jung, YunJae; Surh, Charles D; Miyasaka, Masayuki; Yang, Bo-Gie; Jang, Myoung Ho

    2016-04-04

    Eosinophils play proinflammatory roles in helminth infections and allergic diseases. Under steady-state conditions, eosinophils are abundantly found in the small intestinal lamina propria, but their physiological function is largely unexplored. In this study, we found that small intestinal eosinophils down-regulate Th17 cells. Th17 cells in the small intestine were markedly increased in the ΔdblGATA-1 mice lacking eosinophils, and an inverse correlation was observed between the number of eosinophils and that of Th17 cells in the small intestine of wild-type mice. In addition, small intestinal eosinophils suppressed the in vitro differentiation of Th17 cells, as well as IL-17 production by small intestinal CD4(+)T cells. Unlike other small intestinal immune cells or circulating eosinophils, we found that small intestinal eosinophils have a unique ability to constitutively secrete high levels of IL-1 receptor antagonist (IL-1Ra), a natural inhibitor of IL-1β. Moreover, small intestinal eosinophils isolated from IL-1Ra-deficient mice failed to suppress Th17 cells. Collectively, our results demonstrate that small intestinal eosinophils play a pivotal role in the maintenance of intestinal homeostasis by regulating Th17 cells via production of IL-1Ra. © 2016 Sugawara et al.

  3. Identifying kinase dependency in cancer cells by integrating high-throughput drug screening and kinase inhibition data.

    Science.gov (United States)

    Ryall, Karen A; Shin, Jimin; Yoo, Minjae; Hinz, Trista K; Kim, Jihye; Kang, Jaewoo; Heasley, Lynn E; Tan, Aik Choon

    2015-12-01

    Targeted kinase inhibitors have dramatically improved cancer treatment, but kinase dependency for an individual patient or cancer cell can be challenging to predict. Kinase dependency does not always correspond with gene expression and mutation status. High-throughput drug screens are powerful tools for determining kinase dependency, but drug polypharmacology can make results difficult to interpret. We developed Kinase Addiction Ranker (KAR), an algorithm that integrates high-throughput drug screening data, comprehensive kinase inhibition data and gene expression profiles to identify kinase dependency in cancer cells. We applied KAR to predict kinase dependency of 21 lung cancer cell lines and 151 leukemia patient samples using published datasets. We experimentally validated KAR predictions of FGFR and MTOR dependence in lung cancer cell line H1581, showing synergistic reduction in proliferation after combining ponatinib and AZD8055. KAR can be downloaded as a Python function or a MATLAB script along with example inputs and outputs at: http://tanlab.ucdenver.edu/KAR/. aikchoon.tan@ucdenver.edu. Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  4. Linking stem cell function and growth pattern of intestinal organoids.

    Science.gov (United States)

    Thalheim, Torsten; Quaas, Marianne; Herberg, Maria; Braumann, Ulf-Dietrich; Kerner, Christiane; Loeffler, Markus; Aust, Gabriela; Galle, Joerg

    2018-01-15

    Intestinal stem cells (ISCs) require well-defined signals from their environment in order to carry out their specific functions. Most of these signals are provided by neighboring cells that form a stem cell niche, whose shape and cellular composition self-organize. Major features of this self-organization can be studied in ISC-derived organoid culture. In this system, manipulation of essential pathways of stem cell maintenance and differentiation results in well-described growth phenotypes. We here provide an individual cell-based model of intestinal organoids that enables a mechanistic explanation of the observed growth phenotypes. In simulation studies of the 3D structure of expanding organoids, we investigate interdependences between Wnt- and Notch-signaling which control the shape of the stem cell niche and, thus, the growth pattern of the organoids. Similar to in vitro experiments, changes of pathway activities alter the cellular composition of the organoids and, thereby, affect their shape. Exogenous Wnt enforces transitions from branched into a cyst-like growth pattern; known to occur spontaneously during long term organoid expansion. Based on our simulation results, we predict that the cyst-like pattern is associated with biomechanical changes of the cells which assign them a growth advantage. The results suggest ongoing stem cell adaptation to in vitro conditions during long term expansion by stabilizing Wnt-activity. Our study exemplifies the potential of individual cell-based modeling in unraveling links between molecular stem cell regulation and 3D growth of tissues. This kind of modeling combines experimental results in the fields of stem cell biology and cell biomechanics constituting a prerequisite for a better understanding of tissue regeneration as well as developmental processes. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. The Lgr5 intestinal stem cell signature: robust expression of proposed quiescent '+4' cell markers

    NARCIS (Netherlands)

    Muñoz, Javier; Stange, Daniel E.; Schepers, Arnout G.; van de Wetering, Marc; Koo, Bon-Kyoung; Itzkovitz, Shalev; Volckmann, Richard; Kung, Kevin S.; Koster, Jan; Radulescu, Sorina; Myant, Kevin; Versteeg, Rogier; Sansom, Owen J.; van Es, Johan H.; Barker, Nick; van Oudenaarden, Alexander; Mohammed, Shabaz; Heck, Albert J. R.; Clevers, Hans

    2012-01-01

    Two types of stem cells are currently defined in small intestinal crypts: cycling crypt base columnar (CBC) cells and quiescent '+4' cells. Here, we combine transcriptomics with proteomics to define a definitive molecular signature for Lgr5(+) CBC cells. Transcriptional profiling of FACS-sorted

  6. Helicobacter pylori induces cell migration and invasion through casein kinase 2 in gastric epithelial cells.

    Science.gov (United States)

    Lee, Yeo Song; Lee, Do Yeon; Yu, Da Yeon; Kim, Shin; Lee, Yong Chan

    2014-12-01

    Chronic infection with Helicobacter pylori (H. pylori) is causally linked with gastric carcinogenesis. Virulent H. pylori strains deliver bacterial CagA into gastric epithelial cells. Induction of high motility and an elongated phenotype is considered to be CagA-dependent process. Casein kinase 2 plays a critical role in carcinogenesis through signaling pathways related to the epithelial mesenchymal transition. This study was aimed to investigate the effect of H. pylori infection on the casein kinase 2-mediated migration and invasion in gastric epithelial cells. AGS or MKN28 cells as human gastric epithelial cells and H. pylori strains Hp60190 (ATCC 49503, CagA(+)) and Hp8822 (CagA(-)) were used. Cells were infected with H. pylori at multiplicity of infection of 100 : 1 for various times. We measured in vitro kinase assay to examine casein kinase 2 activity and performed immunofluorescent staining to observe E-cadherin complex. We also examined β-catenin transactivation through promoter assay and MMP7 expression by real-time PCR and ELISA. H. pylori upregulates casein kinase 2 activity and inhibition of casein kinase 2 in H. pylori-infected cells profoundly suppressed cell invasiveness and motility. We confirmed that casein kinase 2 mediates membranous α-catenin depletion through dissociation of the α-/β-catenin complex in H. pylori-infected cells. We also found that H. pylori induces β-catenin nuclear translocation and increases MMP7 expressions mediated through casein kinase 2. We show for the first time that CagA(+) H. pylori upregulates cellular invasiveness and motility through casein kinase 2. The demonstration of a mechanistic interplay between H. pylori and casein kinase 2 provides important insights into the role of CagA(+) H. pylori in the gastric cancer invasion and metastasis. © 2014 John Wiley & Sons Ltd.

  7. The Bacterial Species Campylobacter jejuni Induce Diverse Innate Immune Responses in Human and Avian Intestinal Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Daniel A. John

    2017-09-01

    Full Text Available Campylobacter remain the major cause of human gastroenteritis in the Developed World causing a significant burden to health services. Campylobacter are pathogens in humans and chickens, although differences in mechanistic understanding are incomplete, in part because phenotypic strain diversity creates inconsistent findings. Here, we took Campylobacter jejuni isolates (n = 100 from multi-locus sequence typed collections to assess their pathogenic diversity, through their inflammatory, cytotoxicity, adhesion, invasion and signaling responses in a high-throughput model using avian and human intestinal epithelial cells. C. jejuni induced IL-8 and CXCLi1/2 in human and avian epithelial cells, respectively, in a MAP kinase-dependent manner. In contrast, IL-10 responses in both cell types were PI 3-kinase/Akt-dependent. C. jejuni strains showed diverse levels of invasion with high invasion dependent on MAP kinase signaling in both cell lines. C. jejuni induced diverse cytotoxic responses in both cell lines with cdt-positive isolates showing significantly higher toxicity. Blockade of endocytic pathways suggested that invasion by C. jejuni was clathrin- and dynamin-dependent but caveolae- independent in both cells. In contrast, IL-8 (and CXCLi1/2 production was dependent on clathrin, dynamin, and caveolae. This study is important because of its scale, and the data produced, suggesting that avian and human epithelial cells use similar innate immune pathways where the magnitude of the response is determined by the phenotypic diversity of the Campylobacter species.

  8. Genomic dissection of conserved transcriptional regulation in intestinal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Colin R Lickwar

    2017-08-01

    Full Text Available The intestinal epithelium serves critical physiologic functions that are shared among all vertebrates. However, it is unknown how the transcriptional regulatory mechanisms underlying these functions have changed over the course of vertebrate evolution. We generated genome-wide mRNA and accessible chromatin data from adult intestinal epithelial cells (IECs in zebrafish, stickleback, mouse, and human species to determine if conserved IEC functions are achieved through common transcriptional regulation. We found evidence for substantial common regulation and conservation of gene expression regionally along the length of the intestine from fish to mammals and identified a core set of genes comprising a vertebrate IEC signature. We also identified transcriptional start sites and other putative regulatory regions that are differentially accessible in IECs in all 4 species. Although these sites rarely showed sequence conservation from fish to mammals, surprisingly, they drove highly conserved IEC expression in a zebrafish reporter assay. Common putative transcription factor binding sites (TFBS found at these sites in multiple species indicate that sequence conservation alone is insufficient to identify much of the functionally conserved IEC regulatory information. Among the rare, highly sequence-conserved, IEC-specific regulatory regions, we discovered an ancient enhancer upstream from her6/HES1 that is active in a distinct population of Notch-positive cells in the intestinal epithelium. Together, these results show how combining accessible chromatin and mRNA datasets with TFBS prediction and in vivo reporter assays can reveal tissue-specific regulatory information conserved across 420 million years of vertebrate evolution. We define an IEC transcriptional regulatory network that is shared between fish and mammals and establish an experimental platform for studying how evolutionarily distilled regulatory information commonly controls IEC development

  9. Action of cholera toxin in the intestinal epithelial cells

    International Nuclear Information System (INIS)

    Hyun, C.S.

    1982-01-01

    The primary event in the action of cholera toxin on the isolated chick intestinal epithelial cell is its interaction with the cell membrane. This involves a large number (17 million per cell) of high affinity binding sites which belong to a single class. Binding of biologically active 125 I-labeled toxin is rapid, temperature-dependent, reversible, and saturable over a wide range of concentrations and includes only a small contribution from nonspecific sites. A characteristic lag phase of 10 min occurs following the complete binding of toxin before any increase in cellular cAMP levels can be detected in the isolated cells. The response (elevation of cellular cAMP) of the enterocytes to cholera toxin is linear with time for 40-50 min and causes a six- to eight-fold increase over control levels at steady stae. cAMP and agents that increase cAMP production inhibit Cl - -independent Na + influx into the isolated enterocytes whereas chlorporomazine (CPZ) which completely abolishes toxin-induced elevation of cAMP both reverses and prevents the cAMP-mediated inhibition of Na + entry. Correlation between cellular cAMP levels and the magnitude of Na + influx into the enterocytes provides evidence for a cAMP-mediated control of intestinal Na + uptake, which may represent the mechanistic basis for the antiabsorptive effect of CT and Na + during induction of intestinal secretion. The effect of cAMP on Na + but no Cl - influx in our villus cell preparation can be partially explained in terms of a cAMP-regulated Na + /H + neutral exchange system

  10. Intestinal cell proliferation following hyperthermia-radiation combinations

    International Nuclear Information System (INIS)

    Burholt, D.R.; Wilkinson, D.A.; Shrivastava, P.N.

    1987-01-01

    The present work is an investigation of the extent to which hyperthermia enhances x-ray induced inhibition of intestinal epithelial cell proliferation in mice. Hyperthermia was achieved by whole body immersion of anesthetized ice in a temperature controlled water bath (+-0.1 0 C). Post-treatment proliferative activity was monitored by determining the incorporation of /sup 3/H-TdR into intestinal crypt cells and by the counting of epithelial cell mitotic figures. Initial levels of cell kill were assessed by the microcolony crypt survival technique. All heat treatments were 41.5 0 C for 0.5h. Heat alone reduced the /sup 3/H-TdR incorporation to 50% of the control value by 2h post-treatment. This was followed by a return to control value by 10h and a slight hyperplasia at 24h. Heat either immediately before or after 2Gy abdominal field x-irradiation produced a prolonged period of depressed cell proliferation: /sup 3/H-TdR incorporation remained below control value for the first 24h. As the heat and radiation were separated in time from each other (up to 4h) the interaction between the two decreased. The development of thermotolerance was observed following the second and third treatment during either a heat-only or a heat-radiation multifraction treatments schedule with the treatment spaced 24h apart

  11. Carbachol ameliorates lipopolysaccharide-induced intestinal epithelial tight junction damage by down-regulating NF-{kappa}{beta} and myosin light-chain kinase pathways

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Ying [Department of Anesthesia, Critical Care Medicine and Emergency Medicine Center, Zhongnan Hospital, Wuhan University, Wuhan 430071, Hubei Province, People' s Republic of China (China); Li, Jianguo, E-mail: 2010lijianguo@sina.cn [Department of Anesthesia, Critical Care Medicine and Emergency Medicine Center, Zhongnan Hospital, Wuhan University, Wuhan 430071, Hubei Province, People' s Republic of China (China)

    2012-11-16

    Highlights: Black-Right-Pointing-Pointer Carbachol reduced the lipopolysaccharide-induced intestinal barrier breakdown. Black-Right-Pointing-Pointer Carbachol ameliorated the lipopolysaccharide-induced ileal tight junction damage. Black-Right-Pointing-Pointer Carbachol prevented the LPS-induced NF-{kappa}{beta} and myosin light-chain kinase activation. Black-Right-Pointing-Pointer Carbachol exerted its beneficial effects in an {alpha}7 nicotinic receptor-dependent manner. -- Abstract: Carbachol is a cholinergic agonist that protects the intestines after trauma or burn injury. The present study determines the beneficial effects of carbachol and the mechanisms by which it ameliorates the lipopolysaccharide (LPS)-induced intestinal barrier breakdown. Rats were injected intraperitoneally with 10 mg/kg LPS. Results showed that the gut barrier permeability was reduced, the ultrastructural disruption of tight junctions (TJs) was prevented, the redistribution of zonula occludens-1 and claudin-2 proteins was partially reversed, and the nuclear factor-kappa beta (NF-{kappa}{beta}) and myosin light-chain kinase (MLCK) activation in the intestinal epithelium were suppressed after carbachol administration in LPS-exposed rats. Pretreatment with the {alpha}7 nicotinic acetylcholine receptor ({alpha}7nAchR) antagonist {alpha}-bungarotoxin blocked the protective action of carbachol. These results suggested that carbachol treatment can protect LPS-induced intestinal barrier dysfunction. Carbachol exerts its beneficial effect on the amelioration of the TJ damage by inhibiting the NF-{kappa}{beta} and MLCK pathways in an {alpha}7nAchR-dependent manner.

  12. IRF8 Transcription-Factor-Dependent Classical Dendritic Cells Are Essential for Intestinal T Cell Homeostasis.

    Science.gov (United States)

    Luda, Katarzyna M; Joeris, Thorsten; Persson, Emma K; Rivollier, Aymeric; Demiri, Mimoza; Sitnik, Katarzyna M; Pool, Lieneke; Holm, Jacob B; Melo-Gonzalez, Felipe; Richter, Lisa; Lambrecht, Bart N; Kristiansen, Karsten; Travis, Mark A; Svensson-Frej, Marcus; Kotarsky, Knut; Agace, William W

    2016-04-19

    The role of dendritic cells (DCs) in intestinal immune homeostasis remains incompletely defined. Here we show that mice lacking IRF8 transcription-factor-dependent DCs had reduced numbers of T cells in the small intestine (SI), but not large intestine (LI), including an almost complete absence of SI CD8αβ(+) and CD4(+)CD8αα(+) T cells; the latter requiring β8 integrin expression by migratory IRF8 dependent CD103(+)CD11b(-) DCs. SI homing receptor induction was impaired during T cell priming in mesenteric lymph nodes (MLN), which correlated with a reduction in aldehyde dehydrogenase activity by SI-derived MLN DCs, and inefficient T cell localization to the SI. These mice also lacked intestinal T helper 1 (Th1) cells, and failed to support Th1 cell differentiation in MLN and mount Th1 cell responses to Trichuris muris infection. Collectively these results highlight multiple non-redundant roles for IRF8 dependent DCs in the maintenance of intestinal T cell homeostasis. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. Protein kinase Cepsilon is important for migration of neuroblastoma cells

    International Nuclear Information System (INIS)

    Stensman, Helena; Larsson, Christer

    2008-01-01

    Migration is important for the metastatic capacity and thus for the malignancy of cancer cells. There is limited knowledge on regulatory factors that promote the migration of neuroblastoma cells. This study investigates the hypothesis that protein kinase C (PKC) isoforms regulate neuroblastoma cell motility. PKC isoforms were downregulated with siRNA or modulated with activators and inhibitors. Migration was analyzed with scratch and transwell assays. Protein phosphorylation and expression levels were measured with Western blot. Stimulation with 12-O-tetradecanoylphorbol-13-acetate (TPA) induced migration of SK-N-BE(2)C neuroblastoma cells. Treatment with the general protein kinase C (PKC) inhibitor GF109203X and the inhibitor of classical isoforms Gö6976 inhibited migration while an inhibitor of PKCβ isoforms did not have an effect. Downregulation of PKCε, but not of PKCα or PKCδ, with siRNA led to a suppression of both basal and TPA-stimulated migration. Experiments using PD98059 and LY294002, inhibitors of the Erk and phosphatidylinositol 3-kinase (PI3K) pathways, respectively, showed that PI3K is not necessary for TPA-induced migration. The Erk pathway might be involved in TPA-induced migration but not in migration driven by PKCε. TPA induced phosphorylation of the PKC substrate myristoylated alanine-rich C kinase substrate (MARCKS) which was suppressed by the PKC inhibitors. Treatment with siRNA oligonucleotides against different PKC isoforms before stimulation with TPA did not influence the phosphorylation of MARCKS. PKCε is important for migration of SK-N-BE(2)C neuroblastoma cells. Neither the Erk pathway nor MARCKS are critical downstream targets of PKCε but they may be involved in TPA-mediated migration

  14. Protein kinase C signaling and cell cycle regulation

    Directory of Open Access Journals (Sweden)

    Adrian R Black

    2013-01-01

    Full Text Available A link between T cell proliferation and the protein kinase C (PKC family of serine/threonine kinases has been recognized for about thirty years. However, despite the wealth of information on PKC-mediated control of T cell activation, understanding of the effects of PKCs on the cell cycle machinery in this cell type remains limited. Studies in other systems have revealed important cell cycle-specific effects of PKC signaling that can either positively or negatively impact proliferation. The outcome of PKC activation is highly context-dependent, with the precise cell cycle target(s and overall effects determined by the specific isozyme involved, the timing of PKC activation, the cell type, and the signaling environment. Although PKCs can regulate all stages of the cell cycle, they appear to predominantly affect G0/G1 and G2. PKCs can modulate multiple cell cycle regulatory molecules, including cyclins, cyclin-dependent kinases (cdks, cdk inhibitors and cdc25 phosphatases; however, evidence points to Cip/Kip cdk inhibitors and D-type cyclins as key mediators of PKC-regulated cell cycle-specific effects. Several PKC isozymes can target Cip/Kip proteins to control G0/G1→S and/or G2→M transit, while effects on D-type cyclins regulate entry into and progression through G1. Analysis of PKC signaling in T cells has largely focused on its roles in T cell activation; thus, observed cell cycle effects are mainly positive. A prominent role is emerging for PKCθ, with non-redundant functions of other isozymes also described. Additional evidence points to PKCδ as a negative regulator of the cell cycle in these cells. As in other cell types, context-dependent effects of individual isozymes have been noted in T cells, and Cip/Kip cdk inhibitors and D-type cyclins appear to be major PKC targets. Future studies are anticipated to take advantage of the similarities between these various systems to enhance understanding of PKC-mediated cell cycle regulation in

  15. Plant cell wall signalling and receptor-like kinases.

    Science.gov (United States)

    Wolf, Sebastian

    2017-02-15

    Communication between the extracellular matrix and the cell interior is essential for all organisms as intrinsic and extrinsic cues have to be integrated to co-ordinate development, growth, and behaviour. This applies in particular to plants, the growth and shape of which is governed by deposition and remodelling of the cell wall, a rigid, yet dynamic, extracellular network. It is thus generally assumed that cell wall surveillance pathways exist to monitor the state of the wall and, if needed, elicit compensatory responses such as altered expression of cell wall remodelling and biosynthesis genes. Here, I highlight recent advances in the field of cell wall signalling in plants, with emphasis on the role of plasma membrane receptor-like kinase complexes. In addition, possible roles for cell wall-mediated signalling beyond the maintenance of cell wall integrity are discussed. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  16. Regeneration of stem-cells in intestinal epithelium after irradiation

    International Nuclear Information System (INIS)

    Hendry, J.H.

    1979-01-01

    Stem-cells can be defined as pluripotent progenitor cells, capable of both self-renewal and differentitation into all the functional end-cells typical of that cell family. Intestinal crypts contain population of cells which is capable of a) self-renewal following the severe depletion after radiation injury, b) replacing all other cypt cell types, and c) regeneration following repeated depletion (in colon). These are the properties of stem cells. Most measurements of the rate of regeneration of these cells following the severe depletion by radiation have been made by employing large test dose at increasing times. Such measurements have produced widely differing rates of increase in the survival under the test dose, from 4 hours (macrocolonies in jejunum) to 43 hours (microcolonies in stomach). In other tissues, large single test doses have been used to derive the time of doubling survival ratio e.g. for epidermal clones. Although cryptogenic cell number per crypt can be virtually restored by day 4 after a single dose and probably after many such doses, the status quo cannot be reached until the number of crypts is restored to normal. Stem cell numbers form a necessary part of the integrity of epitheliums. The quality of the stem cell function of survivors as expressed in the differentiated progeny, and the maintenance of function of the supportive environment are equally important for late radiation damage. (Yamashita, S.)

  17. SITS-sensitive Cl- conductance pathway in chick intestinal cells

    International Nuclear Information System (INIS)

    Montrose, M.; Randles, J.; Kimmich, G.A.

    1987-01-01

    The unidirectional influx of 36 Cl - into isolated chick epithelial cells is 30% inhibited by 300 μM SITS. Characteristics of the SITS-sensitive flux pathway were examined in terms of sensitivity to changes in membrane potential and intracellular pH. Potential dependence was evaluated using unidirectional influx of [ 14 C]tetraphenylphosphonium ([ 14 C]-TPP + ) as a qualitative sensor of diffusion potentials created by experimentally imposed gradients of CL - . Steady-state distribution of [ 14 C]methylamine ([ 14 C]MA) was used to examine for Cl - -dependent changes in intracellular pH. Imposed Na + gradients, but not Cl - gradients, induce changes in [ 14 C]MA distribution. SITS does not alter the [ 14 C]MA distribution observed in cells with imposed gradients of Na + and Cl - . Both results suggest that inhibition of Cl - influx. However, if relative permeabilities for ion pairs via conductance pathways are compared, it can be shown that SITS causes a marked reduction of P Cl relative to either P Na or P K . SITS also inhibits electrically induced influx of [ 14 C]TPP + or [ 14 C]α-methylglucoside driven by imposed Cl - influx can be blocked by SITS. These observations are all consistent with a SITS-sensitive Cl - conductance pathway associated with the plasma membrane of chick intestinal cells. No Cl - -OH - exchange capability can be detected for chick intestinal cells

  18. Enhancing oral vaccine potency by targeting intestinal M cells.

    Directory of Open Access Journals (Sweden)

    Ali Azizi

    2010-11-01

    Full Text Available The immune system in the gastrointestinal tract plays a crucial role in the control of infection, as it constitutes the first line of defense against mucosal pathogens. The attractive features of oral immunization have led to the exploration of a variety of oral delivery systems. However, none of these oral delivery systems have been applied to existing commercial vaccines. To overcome this, a new generation of oral vaccine delivery systems that target antigens to gut-associated lymphoid tissue is required. One promising approach is to exploit the potential of microfold (M cells by mimicking the entry of pathogens into these cells. Targeting specific receptors on the apical surface of M cells might enhance the entry of antigens, initiating the immune response and consequently leading to protection against mucosal pathogens. In this article, we briefly review the challenges associated with current oral vaccine delivery systems and discuss strategies that might potentially target mouse and human intestinal M cells.

  19. Cdx2 modulates proliferation in normal human intestinal epithelial crypt cells

    International Nuclear Information System (INIS)

    Escaffit, Fabrice; Pare, Frederic; Gauthier, Remy; Rivard, Nathalie; Boudreau, Francois; Beaulieu, Jean-Francois

    2006-01-01

    The homeobox gene Cdx2 is involved in the regulation of the expression of intestine specific markers such as sucrase-isomaltase and lactase-phlorizin hydrolase. Previous studies performed with immortalized or transformed intestinal cell lines have provided evidence that Cdx2 can promote morphological and functional differentiation in these experimental models. However, no data exist concerning the implication of this factor in normal human intestinal cell physiology. In the present work, we have investigated the role of Cdx2 in normal human intestinal epithelial crypt (HIEC) cells that lack this transcription factor. The establishment of HIEC cells expressing Cdx2 in an inducible manner shows that forced expression of Cdx2 significantly alters the proliferation of intestinal crypt cells and stimulates dipeptidylpeptidase IV expression but is not sufficient to trigger intestinal terminal differentiation. These observations suggest that Cdx2 requires additional factors to activate the enterocyte differentiation program in normal undifferentiated cells

  20. Human Primary Intestinal Epithelial Cells as an Improved In Vitro Model for Cryptosporidium parvum Infection

    Science.gov (United States)

    Cabada, Miguel M.; Nichols, Joan; Gomez, Guillermo; White, A. Clinton

    2013-01-01

    The study of human intestinal pathogens has been limited by the lack of methods for the long-term culture of primary human intestinal epithelial cells (PECs). The development of infection models with PECs would allow a better understanding of host-parasite interactions. The objective of this study was to develop a novel method for prolonged in vitro cultivation of PECs that can be used to study Cryptosporidium infection. We isolated intact crypts from human intestines removed during weight loss surgery. The fragments of intestinal layers were cultivated with culture medium supplemented with growth factors and antiapoptotic molecules. After 7 days, the PECs formed self-regenerating cell clusters, forming villi that resemble intestinal epithelium. The PECs proliferated and remained viable for at least 60 days. The cells expressed markers for intestinal stem cells, epithelial cells, and mature enterocytes. The PECs were infected with Cryptosporidium. In contrast to older models in which parasite numbers decay, the burden of parasites increased for >120 h. In summary, we describe here a novel method for the cultivation of self-regenerating human epithelial cells from small intestinal crypts, which contain both intestinal stem cells and mature villus cells. We present data that suggest these cells support Cryptosporidium better than existing cell lines. PECs should provide an improved tool for studying host-parasite interactions involving Cryptosporidium and other intestinal pathogens. PMID:23509153

  1. Diacylglycerol kinases in T cell tolerance and effector function

    Directory of Open Access Journals (Sweden)

    Shelley S Chen

    2016-11-01

    Full Text Available Diacylglycerol kinases (DGKs are a family of enzymes that regulate the relative levels of diacylglycerol (DAG and phosphatidic acid (PA in cells by phosphorylating DAG to produce PA. Both DAG and PA are important second messengers cascading T cell receptor (TCR signal by recruiting multiple effector molecules such as RasGRP1, PKC, and mTOR. Studies have revealed important physiological functions of DGKs in the regulation of receptor signaling and the development and activation of immune cells. In this review, we will focus on recent progresses in our understanding of two DGK isoforms,  and , in CD8 T effector and memory cell differentiation, regulatory T cell development and function, and invariant NKT cell development and effector lineage differentiation.

  2. Culture of human intestinal epithelial cell using the dissociating enzyme thermolysin and endothelin-3

    OpenAIRE

    Liu, Z.; Zhang, P.; Zhou, Y.; Qin, H.; Shen, T.

    2010-01-01

    Epithelium, a highly dynamic system, plays a key role in the homeostasis of the intestine. However, thus far a human intestinal epithelial cell line has not been established in many countries. Fetal tissue was selected to generate viable cell cultures for its sterile condition, effective generation, and differentiated character. The purpose of the present study was to culture human intestinal epithelial cells by a relatively simple method. Thermolysin was added to improve the yield of epithel...

  3. Culture of human intestinal epithelial cell using the dissociating enzyme thermolysin and endothelin-3

    Directory of Open Access Journals (Sweden)

    Z. Liu

    2010-05-01

    Full Text Available Epithelium, a highly dynamic system, plays a key role in the homeostasis of the intestine. However, thus far a human intestinal epithelial cell line has not been established in many countries. Fetal tissue was selected to generate viable cell cultures for its sterile condition, effective generation, and differentiated character. The purpose of the present study was to culture human intestinal epithelial cells by a relatively simple method. Thermolysin was added to improve the yield of epithelial cells, while endothelin-3 was added to stimulate their growth. By adding endothelin-3, the achievement ratio (viable cell cultures/total cultures was enhanced to 60% of a total of 10 cultures (initiated from 8 distinct fetal small intestines, allowing the generation of viable epithelial cell cultures. Western blot, real-time PCR and immunofluorescent staining showed that cytokeratins 8, 18 and mouse intestinal mucosa-1/39 had high expression levels in human intestinal epithelial cells. Differentiated markers such as sucrase-isomaltase, aminopeptidase N and dipeptidylpeptidase IV also showed high expression levels in human intestinal epithelial cells. Differentiated human intestinal epithelial cells, with the expression of surface markers (cytokeratins 8, 18 and mouse intestinal mucosa-1/39 and secretion of cytokines (sucrase-isomaltase, aminopeptidase N and dipeptidylpeptidase IV, may be cultured by the thermolysin and endothelin-3 method and maintained for at least 20 passages. This is relatively simple, requiring no sophisticated techniques or instruments, and may have a number of varied applications.

  4. Ghrelin augments murine T-cell proliferation by activation of the phosphatidylinositol-3-kinase, extracellular signal-regulated kinase and protein kinase C signaling pathways

    Science.gov (United States)

    Lee, Jun Ho; Patel, Kalpesh; Tae, Hyun Jin; Lustig, Ana; Kim, Jie Wan; Mattson, Mark P.; Taub, Dennis D.

    2014-01-01

    Thymic atrophy occurs during normal aging, and is accelerated by exposure to chronic stressors that elevate glucocorticoid levelsand impair the naïve T cell output. The orexigenic hormone ghrelin was recently shown to attenuate age-associated thymic atrophy. Here, we report that ghrelin enhances the proliferation of murine CD4+ primary T cells and a CD4+ T-cell line. Ghrelin induced activation of the ERK1/2 and Akt signaling pathways, via upstream activation of phosphatidylinositol-3-kinase and protein kinase C, to enhance T-cell proliferation. Moreover, ghrelin induced expression of the cell cycle proteins cyclin D1, cyclin E, cyclin-dependent kinase 2 (CDK2) and retinoblastoma phosphorylation. Finally, ghrelin activated the above-mentioned signaling pathways and stimulated thymocyte proliferation in young and older mice in vivo. PMID:25447526

  5. Action of cholera toxin in the intestinal epithelial cells

    International Nuclear Information System (INIS)

    Hyun, C.S.

    1982-01-01

    The primary event in the action of cholera toxin on the isolated chick intestinal epithelial cell is its interaction with a large number of high affinity binding sites in the cell membrane. Binding of 125 I-labeled toxin is rapid, temperature-dependent, reversible, and saturable over a wide range of concentrations and includes only a small contribution from nonspecific sites. A characteristic lag phase of 10 min occurs following the complete binding of toxin before any increase in cellular cAMP levels can be detected. The response (elevation of cellular cAMP) is linear with time for 40 to 50 min and causes a six- to eight-fold increase over control levels (10 to 15 picomole cAMP/mg cellular protein) at steady state. cAMP and agents that increase cAMP production inhibit Cl - -independent Na + influx into the isolated enterocytes whereas chlorpromazine (CPZ) which completely abolishes toxin-induced elevation of cAMP both reverses and prevents the cAMP-mediated inhibition of Na + entry. Correlation between cellular cAMP levels and the magnitude of Na + influx provides evidence for a cAMP-mediated control of intestinal Na + uptake, which may represent the mechanistic basis for the antiabsorptive effect of CT on Na + during induction of intestinal secretion. The effect of cAMP on Na + but not Cl - influx preparations can be partially explained in terms of a cAMP-regulated Na + /H + neutral exchange system. Data on the coupling relationship between Na + transport and the intra- and extracellular pH in the enterocytes show that an amiloride-sensitive electroneutral Na + /H + exchange process occurs. This coupling between Na + and H + is partially inhibited by CT and dbcAMP, suggesting that the Na + /H + exchange may be a cAMP-regulated process. 31 references, 32 figures, 5 tables

  6. Human intestinal dendritic cells as controllers of mucosal immunity

    Directory of Open Access Journals (Sweden)

    David Bernardo

    2013-06-01

    Full Text Available Dendritic cells are the most potent, professional antigen-presenting cells in the body; following antigen presentation they control the type (proinflammatory/regulatory of immune response that will take place, as well as its location. Given their high plasticity and maturation ability in response to local danger signals derived from innate immunity, dendritic cells are key actors in the connection between innate immunity and adaptive immunity responses. In the gut dendritic cells control immune tolerance mechanisms against food and/or commensal flora antigens, and are also capable of initiating an active immune response in the presence of invading pathogens. Dendritic cells are thus highly efficient in controlling the delicate balance between tolerance and immunity in an environment so rich in antigens as the gut, and any factor involving these cells may impact their function, ultimately leading to the development of bowel conditions such as celiac disease or inflammatory bowel disease. In this review we shall summarize our understanding of human intestinal dendritic cells, their ability to express and induce migration markers, the various environmental factors modulating their properties, their subsets in the gut, and the problems entailed by their study, including identification strategies, differences between humans and murine models, and phenotypical variations along the gastrointestinal tract.

  7. Live Cells Decreased Methane Production in Intestinal Content of Pigs

    Directory of Open Access Journals (Sweden)

    Y. L. Gong

    2013-06-01

    Full Text Available An in vitro gas production technique was used in this study to elucidate the effect of two strains of active live yeast on methane (CH4 production in the large intestinal content of pigs to provide an insight to whether active live yeast could suppress CH4 production in the hindgut of pigs. Treatments used in this study include blank (no substrate and no live yeast cells, control (no live yeast cells and yeast (YST supplementation groups (supplemented with live yeast cells, YST1 or YST2. The yeast cultures contained 1.8×1010 cells per g, which were added at the rates of 0.2 mg and 0.4 mg per ml of the fermented inoculum. Large intestinal contents were collected from 2 Duroc×Landrace×Yorkshire pigs, mixed with a phosphate buffer (1:2, and incubated anaerobically at 39°C for 24 h using 500 mg substrate (dry matter (DM basis. Total gas and CH4 production decreased (p<0.05 with supplementation of yeast. The methane production reduction potential (MRP was calculated by assuming net methane concentration for the control as 100%. The MRP of yeast 2 was more than 25%. Compared with the control group, in vitro DM digestibility (IVDMD and total volatile fatty acids (VFA concentration increased (p<0.05 in 0.4 mg/ml YST1 and 0.2 mg/ml YST2 supplementation groups. Proportion of propionate, butyrate and valerate increased (p<0.05, but that of acetate decreased (p<0.05, which led to a decreased (p<0.05 acetate: propionate (A: P ratio in the both YST2 treatments and the 0.4 mg/ml YST 1 supplementation groups. Hydrogen recovery decreased (p<0.05 with yeast supplementation. Quantity of methanogenic archaea per milliliter of inoculum decreased (p<0.05 with yeast supplementation after 24 h of incubation. Our results suggest that live yeast cells suppressed in vitro CH4 production when inoculated into the large intestinal contents of pigs and shifted the fermentation pattern to favor propionate production together with an increased population of acetogenic

  8. Advanced three-dimensional culture of equine intestinal epithelial stem cells.

    Science.gov (United States)

    Stewart, A Stieler; Freund, J M; Gonzalez, L M

    2018-03-01

    Intestinal epithelial stem cells are critical to epithelial repair following gastrointestinal injury. The culture of intestinal stem cells has quickly become a cornerstone of a vast number of new research endeavours that range from determining tissue viability to testing drug efficacy for humans. This study aims to describe the methods of equine stem cell culture and highlights the future benefits of these techniques for the advancement of equine medicine. To describe the isolation and culture of small intestinal stem cells into three-dimensional (3D) enteroids in horses without clinical gastrointestinal abnormalities. Descriptive study. Intestinal samples were collected by sharp dissection immediately after euthanasia. Intestinal crypts containing intestinal stem cells were dissociated from the underlying tissue layers, plated in a 3D matrix and supplemented with growth factors. After several days, resultant 3D enteroids were prepared for immunofluorescent imaging and polymerase chain reaction (PCR) analysis to detect and characterise specific cell types present. Intestinal crypts were cryopreserved immediately following collection and viability assessed. Intestinal crypts were successfully cultured and matured into 3D enteroids containing a lumen and budding structures. Immunofluorescence and PCR were used to confirm the existence of stem cells and all post mitotic, mature cell types, described to exist in the horse intestinal epithelium. Previously frozen crypts were successfully cultured following a freeze-thaw cycle. Tissues were all derived from normal horses. Application of this technique for the study of specific disease was not performed at this time. The successful culture of equine intestinal crypts into 3D "mini-guts" allows for in vitro studies of the equine intestine. Additionally, these results have relevance to future development of novel therapies that harness the regenerative potential of equine intestine in horses with gastrointestinal disease

  9. Urokinase and the intestinal mucosa: evidence for a role in epithelial cell turnover

    OpenAIRE

    Gibson, P; Birchall, I; Rosella, O; Albert, V; Finch, C; Barkla, D; Young, G

    1998-01-01

    Background—The functions of urokinase in intestinal epithelia are unknown. 
Aims—To determine the relation of urokinase expressed by intestinal epithelial cells to their position in the crypt-villus/surface axis and of mucosal urokinase activity to epithelial proliferative kinetics in the distal colon. 
Methods—Urokinase expression was examined immunohistochemically in human intestinal mucosa. Urokinase activity was measured colorimetrically in epithelial cells isolated sequ...

  10. Bovine TLR2 and TLR4 mediate Cryptosporidium parvum recognition in bovine intestinal epithelial cells.

    Science.gov (United States)

    Yang, Zhengtao; Fu, Yunhe; Gong, Pengtao; Zheng, Jingtong; Liu, Li; Yu, Yuqiang; Li, Jianhua; Li, He; Yang, Ju; Zhang, Xichen

    2015-08-01

    Cryptosporidium parvum (C. parvum) is an intestinal parasite that causes diarrhea in neonatal calves. It results in significant morbidity of neonatal calves and economic losses for producers worldwide. Innate resistance against C. parvum is thought to depend on engagement of pattern recognition receptors. However, the role of innate responses to C. parvum has not been elucidated in bovine. The aim of this study was to evaluate the role of TLRs in host-cell responses during C. parvum infection of cultured bovine intestinal epithelial cells. The expressions of TLRs in bovine intestinal epithelial cells were detected by qRT-PCR. To determine which, if any, TLRs may play a role in the response of bovine intestinal epithelial cells to C. parvum, the cells were stimulated with C. parvum and the expression of TLRs were tested by qRT-PCR. The expression of NF-κB was detected by western blotting. Further analyses were carried out in bovine TLRs transfected HEK293 cells and by TLRs-DN transfected bovine intestinal epithelial cells. The results showed that bovine intestinal epithelial cells expressed all known TLRs. The expression of TLR2 and TLR4 were up-regulated when bovine intestinal epithelial cells were treated with C. parvum. Meanwhile, C. parvum induced IL-8 production in TLR2 or TLR4/MD-2 transfected HEK293 cells. Moreover, C. parvum induced NF-κB activation and cytokine expression in bovine intestinal epithelial cells. The induction of NF-κB activation and cytokine expression by C. parvum were reduced in TLR2-DN and TLR4-DN transfected cells. The results showed that bovine intestinal epithelial cells expressed all known TLRs, and bovine intestinal epithelial cells recognized and responded to C. parvum via TLR2 and TLR4. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. ADAM10 regulates Notch function in intestinal stem cells of mice.

    Science.gov (United States)

    Tsai, Yu-Hwai; VanDussen, Kelli L; Sawey, Eric T; Wade, Alex W; Kasper, Chelsea; Rakshit, Sabita; Bhatt, Riha G; Stoeck, Alex; Maillard, Ivan; Crawford, Howard C; Samuelson, Linda C; Dempsey, Peter J

    2014-10-01

    A disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) is a cell surface sheddase that regulates physiologic processes, including Notch signaling. ADAM10 is expressed in all intestinal epithelial cell types, but the requirement for ADAM10 signaling in crypt homeostasis is not well defined. We analyzed intestinal tissues from mice with constitutive (Vil-Cre;Adam10(f/f) mice) and conditional (Vil-CreER;Adam10(f/f) and Leucine-rich repeat-containing GPCR5 [Lgr5]-CreER;Adam10(f/f) mice) deletion of ADAM10. We performed cell lineage-tracing experiments in mice that expressed a gain-of-function allele of Notch in the intestine (Rosa26(NICD)), or mice with intestine-specific disruption of Notch (Rosa26(DN-MAML)), to examine the effects of ADAM10 deletion on cell fate specification and intestinal stem cell maintenance. Loss of ADAM10 from developing and adult intestine caused lethality associated with altered intestinal morphology, reduced progenitor cell proliferation, and increased secretory cell differentiation. ADAM10 deletion led to the replacement of intestinal cell progenitors with 2 distinct, post-mitotic, secretory cell lineages: intermediate-like (Paneth/goblet) and enteroendocrine cells. Based on analysis of Rosa26(NICD) and Rosa26(DN-MAML) mice, we determined that ADAM10 controls these cell fate decisions by regulating Notch signaling. Cell lineage-tracing experiments showed that ADAM10 is required for survival of Lgr5(+) crypt-based columnar cells. Our findings indicate that Notch-activated stem cells have a competitive advantage for occupation of the stem cell niche. ADAM10 acts in a cell autonomous manner within the intestinal crypt compartment to regulate Notch signaling. This process is required for progenitor cell lineage specification and crypt-based columnar cell maintenance. Copyright © 2014 AGA Institute. Published by Elsevier Inc. All rights reserved.

  12. Distinct Roles for Intestinal Epithelial Cell-Specific Hdac1 and Hdac2 in the Regulation of Murine Intestinal Homeostasis.

    Science.gov (United States)

    Gonneaud, Alexis; Turgeon, Naomie; Boudreau, François; Perreault, Nathalie; Rivard, Nathalie; Asselin, Claude

    2016-02-01

    The intestinal epithelium responds to and transmits signals from the microbiota and the mucosal immune system to insure intestinal homeostasis. These interactions are in part conveyed by epigenetic modifications, which respond to environmental changes. Protein acetylation is an epigenetic signal regulated by histone deacetylases, including Hdac1 and Hdac2. We have previously shown that villin-Cre-inducible intestinal epithelial cell (IEC)-specific Hdac1 and Hdac2 deletions disturb intestinal homeostasis. To determine the role of Hdac1 and Hdac2 in the regulation of IEC function and the establishment of the dual knockout phenotype, we have generated villin-Cre murine models expressing one Hdac1 allele without Hdac2, or one Hdac2 allele without Hdac1. We have also investigated the effect of short-term deletion of both genes in naphtoflavone-inducible Ah-Cre and tamoxifen-inducible villin-Cre(ER) mice. Mice with one Hdac1 allele displayed normal tissue architecture, but increased sensitivity to DSS-induced colitis. In contrast, mice with one Hdac2 allele displayed intestinal architecture defects, increased proliferation, decreased goblet cell numbers as opposed to Paneth cells, increased immune cell infiltration associated with fibrosis, and increased sensitivity to DSS-induced colitis. In comparison to dual knockout mice, intermediary activation of Notch, mTOR, and Stat3 signaling pathways was observed. While villin-Cre(ER) Hdac1 and Hdac2 deletions led to an impaired epithelium and differentiation defects, Ah-Cre-mediated deletion resulted in blunted proliferation associated with the induction of a DNA damage response. Our results suggest that IEC determination and intestinal homeostasis are highly dependent on Hdac1 and Hdac2 activity levels, and that changes in the IEC acetylome may alter the mucosal environment. © 2015 Wiley Periodicals, Inc.

  13. Communication between B-Cells and Microbiota for the Maintenance of Intestinal Homeostasis

    Directory of Open Access Journals (Sweden)

    Yuying Liu

    2013-10-01

    Full Text Available The human intestine is populated with an extremely dense and diverse bacterial community. Commensal bacteria act as an important antigenic stimulus producing the maturation of gut-associated lymphoid tissue (GALT. The production of immunoglobulin (Ig A by B-cells in the GALT is one of the immune responses following intestinal colonization of bacteria. The switch of B-cells from IgM to IgA-producing cells in the Peyer’s patches and neighboring lamina propria proceeds by T-cell-dependent and T-cell-independent mechanisms. Several grams of secretory IgA (SIgA are released into the intestine each day. SIgA serves as a first-line of defense in protecting the intestinal epithelium from enteric toxins and pathogenic microorganisms. SIgA has a capacity to directly quench bacterial virulence factors, influence the composition of the intestinal microbiota, and promote the transportation of antigens across the intestinal epithelium to GALT and down-regulate proinflammatory responses associated with the uptake of highly pathogenic bacteria and potentially allergenic antigens. This review summarizes the reciprocal interactions between intestinal B cells and bacteria, specifically, the formation of IgA in the gut, the role of intestinal IgA in the regulation of bacterial communities and the maintenance of intestinal homeostasis, and the effects of probiotics on IgA levels in the gastrointestinal tract.

  14. PaASK1, a mitogen-activated protein kinase kinase kinase that controls cell degeneration and cell differentiation in Podospora anserina.

    Science.gov (United States)

    Kicka, Sébastien; Silar, Philippe

    2004-03-01

    MAPKKK are kinases involved in cell signaling. In fungi, these kinases are known to regulate development, pathogenicity, and the sensing of external conditions. We show here that Podospora anserina strains mutated in PaASK1, a MAPKKK of the MEK family, are impaired in the development of crippled growth, a cell degeneration process caused by C, a nonconventional infectious element. They also display defects in mycelium pigmentation, differentiation of aerial hyphae, and making of fruiting bodies, three hallmarks of cell differentiation during stationary phase in P. anserina. Overexpression of PaASK1 results in exacerbation of crippled growth. PaASK1 is a large protein of 1832 amino acids with several domains, including a region rich in proline and a 60-amino-acid-long polyglutamine stretch. Deletion analysis reveals that the polyglutamine stretch is dispensable for PaASK1 activity, whereas the region that contains the prolines is essential but insufficient to promote full activity. We discuss a model based on the hysteresis of a signal transduction cascade to account for the role of PaASK1 in both cell degeneration and stationary-phase cell differentiation.

  15. Fermented soya bean (tempe) extracts reduce adhesion of enterotoxigenic Escherichia coli to intestinal epithelial cells

    NARCIS (Netherlands)

    Roubos-van den Hil, P.J.; Nout, M.J.R.; Beumer, R.R.; Meulen, van der J.; Zwietering, M.H.

    2009-01-01

    Aims: This study aimed to investigate the effect of processed soya bean, during the successive stages of tempe fermentation and different fermentation times, on adhesion of enterotoxigenic Escherichia coli (ETEC) K88 to intestinal brush border cells as well as Caco-2 intestinal epithelial cells; and

  16. Peroxisomes in intestinal and gallbladder epithelial cells of the stickleback, Gasterosteus aculeatus L. (Teleostei)

    NARCIS (Netherlands)

    Ruiter, A.J.H. de; Veenhuis, M.; Wendelaar Bonga, S.E.

    1988-01-01

    The occurrence of microbodies in the epithelial cells of the intestine and gallbladder of the stickleback, Gasterosteus aculeatus L., is described. In the intestine the organelles are predominantly located in the apical and perinuclear zone of the cells and may contain small crystalline cores. In

  17. A Sox Transcription Factor Is a Critical Regulator of Adult Stem Cell Proliferation in the Drosophila Intestine

    Directory of Open Access Journals (Sweden)

    Fanju W. Meng

    2015-11-01

    Full Text Available Adult organs and their resident stem cells are constantly facing the challenge of adapting cell proliferation to tissue demand, particularly in response to environmental stresses. Whereas most stress-signaling pathways are conserved between progenitors and differentiated cells, stem cells have the specific ability to respond by increasing their proliferative rate, using largely unknown mechanisms. Here, we show that a member of the Sox family of transcription factors in Drosophila, Sox21a, is expressed in intestinal stem cells (ISCs in the adult gut. Sox21a is essential for the proliferation of these cells during both normal epithelium turnover and repair. Its expression is induced in response to tissue damage, downstream of the Jun N-terminal kinase (JNK and extracellular signal-regulated kinase (ERK pathways, to promote ISC proliferation. Although short-lived, Sox21a mutant flies show no developmental defects, supporting the notion that this factor is a specific regulator of adult stem cell proliferation.

  18. Requirement of ATR for maintenance of intestinal stem cells in aging Drosophila.

    Science.gov (United States)

    Park, Joung-Sun; Na, Hyun-Jin; Pyo, Jung-Hoon; Jeon, Ho-Jun; Kim, Young-Shin; Yoo, Mi-Ae

    2015-05-01

    The stem cell genomic stability forms the basis for robust tissue homeostasis, particularly in high-turnover tissues. For the genomic stability, DNA damage response (DDR) is essential. This study was focused on the role of two major DDR-related factors, ataxia telangiectasia-mutated (ATM) and ATM- and RAD3-related (ATR) kinases, in the maintenance of intestinal stem cells (ISCs) in the adultDrosophila midgut. We explored the role of ATM and ATR, utilizing immunostaining with an anti-pS/TQ antibody as an indicator of ATM/ATR activation, γ-irradiation as a DNA damage inducer, and the UAS/GAL4 system for cell type-specific knockdown of ATM, ATR, or both during adulthood. The results showed that the pS/TQ signals got stronger with age and after oxidative stress. The pS/TQ signals were found to be more dependent on ATR rather than on ATM in ISCs/enteroblasts (EBs). Furthermore, an ISC/EB-specific knockdown of ATR, ATM, or both decreased the number of ISCs and oxidative stress-induced ISC proliferation. The phenotypic changes that were caused by the ATR knockdown were more pronounced than those caused by the ATM knockdown; however, our data indicate that ATR and ATM are both needed for ISC maintenance and proliferation; ATR seems to play a bigger role than does ATM.

  19. Oral Administration of Probiotics Increases Paneth Cells and Intestinal Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Silvia I. Cazorla

    2018-04-01

    Full Text Available The huge amount of intestinal bacteria represents a continuing threat to the intestinal barrier. To meet this challenge, gut epithelial cells produce antimicrobial peptides (AMP that act at the forefront of innate immunity. We explore whether this antimicrobial activity and Paneth cells, the main intestinal cell responsible of AMP production, are influenced by probiotics administration, to avoid the imbalance of intestinal microbiota and preserve intestinal barrier. Administration of Lactobacillus casei CRL 431 (Lc 431 and L. paracasei CNCM I-1518 (Lp 1518 to 42 days old mice, increases the number of Paneth cells on small intestine, and the antimicrobial activity against the pathogens Staphylococcus aureus and Salmonella Typhimurium in the intestinal fluids. Specifically, strong damage of the bacterial cell with leakage of cytoplasmic content, and cellular fragmentation were observed in S. Typhimurium and S. aureus. Even more important, probiotics increase the antimicrobial activity of the intestinal fluids at the different ages, from weaning (21 days old to old age (180 days old. Intestinal antimicrobial activity stimulated by oral probiotics, do not influence significantly the composition of total anaerobic bacteria, lactobacilli and enterobacteria in the large intestine, at any age analyzed. This result, together with the antimicrobial activity observed against the same probiotic bacteria; endorse the regular consumption of probiotics without adverse effect on the intestinal homeostasis in healthy individuals. We demonstrate that oral probiotics increase intestinal antimicrobial activity and Paneth cells in order to strengthen epithelial barrier against pathogens. This effect would be another important mechanism by which probiotics protect the host mainly against infectious diseases.

  20. Posttranscriptional Regulation of Cyclooxygenase-2 in Rat Intestinal Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Zhonghua Zhang

    2000-01-01

    Full Text Available Modulation of cyclooxygenase-2 (COX-2 mRNA stability plays an important role in the regulation of its expression by oncogenic Ras. Here, we evaluate COX-2 mRNA stability in response to treatment with two known endogenous promoters of gastrointestinal cancer, the bile acid (chenodeoxycholate; CD and ceramide. Treatment with CD and ceramide resulted in a 10-fold increase in the level of COX-2 protein and a four-fold lengthening of the half-life of COX-2 mRNA. COX-2 mRNA stability was assessed by Northern blot analysis and by evaluating the AU-rich element located in the COX-2 3′-UTR. A known inhibitor of mitogen-activated protein (MAP/extracellular signal-regulated kinase (ERK kinase (MEK, PD98059, reversed the effects of CD or ceramide to stabilize COX-2 mRNA. Overexpression of a dominant-negative ERK-1 or ERK-2 protein also led to destabilization of COX-2 mRNA. Treatment with a p38 MAPK inhibitor, PD169316, or transfection with a dominant-negative p38 MAPK construct reversed the effect of CD or ceramide to stabilize COX-2 mRNA. Expression of a dominant-negative c-Jun N-terminal kinase (JNK had no effect on COX-2 mRNA stability in cells treated with CD or ceramide. We conclude that posttranscriptional mechanisms play an important role in the regulation of COX-2 expression during carcinogenesis.

  1. Exploring the Hypersensitivity of PTEN Deleted Prostate Cancer Stem Cells to WEE1 Tyrosine Kinase Inhibitors

    Science.gov (United States)

    2015-12-01

    AWARD NUMBER: W81XWH-14-1-0251 TITLE: Exploring the Hypersensitivity of PTEN Deleted Prostate Cancer Stem Cells to WEE1 Tyrosine Kinase... Tyrosine Kinase Inhibitors 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-14-1-0251 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Kiran Mahajan 5d...ABSTRACT Central to all cycling cells-including prostate cancer stem cells- is the expression of WEE1 tyrosine kinase. WEE1 monitors duplication of

  2. Src Family Kinases and p38 Mitogen-Activated Protein Kinases Regulate Pluripotent Cell Differentiation in Culture.

    Directory of Open Access Journals (Sweden)

    Boon Siang Nicholas Tan

    Full Text Available Multiple pluripotent cell populations, which together comprise the pluripotent cell lineage, have been identified. The mechanisms that control the progression between these populations are still poorly understood. The formation of early primitive ectoderm-like (EPL cells from mouse embryonic stem (mES cells provides a model to understand how one such transition is regulated. EPL cells form from mES cells in response to l-proline uptake through the transporter Slc38a2. Using inhibitors of cell signaling we have shown that Src family kinases, p38 MAPK, ERK1/2 and GSK3β are required for the transition between mES and EPL cells. ERK1/2, c-Src and GSK3β are likely to be enforcing a receptive, primed state in mES cells, while Src family kinases and p38 MAPK are involved in the establishment of EPL cells. Inhibition of these pathways prevented the acquisition of most, but not all, features of EPL cells, suggesting that other pathways are required. L-proline activation of differentiation is mediated through metabolism and changes to intracellular metabolite levels, specifically reactive oxygen species. The implication of multiple signaling pathways in the process suggests a model in which the context of Src family kinase activation determines the outcomes of pluripotent cell differentiation.

  3. Src Family Kinases and p38 Mitogen-Activated Protein Kinases Regulate Pluripotent Cell Differentiation in Culture

    Science.gov (United States)

    Tan, Boon Siang Nicholas; Kwek, Joly; Wong, Chong Kum Edwin; Saner, Nicholas J.; Yap, Charlotte; Felquer, Fernando; Morris, Michael B.; Gardner, David K.; Rathjen, Peter D.; Rathjen, Joy

    2016-01-01

    Multiple pluripotent cell populations, which together comprise the pluripotent cell lineage, have been identified. The mechanisms that control the progression between these populations are still poorly understood. The formation of early primitive ectoderm-like (EPL) cells from mouse embryonic stem (mES) cells provides a model to understand how one such transition is regulated. EPL cells form from mES cells in response to l-proline uptake through the transporter Slc38a2. Using inhibitors of cell signaling we have shown that Src family kinases, p38 MAPK, ERK1/2 and GSK3β are required for the transition between mES and EPL cells. ERK1/2, c-Src and GSK3β are likely to be enforcing a receptive, primed state in mES cells, while Src family kinases and p38 MAPK are involved in the establishment of EPL cells. Inhibition of these pathways prevented the acquisition of most, but not all, features of EPL cells, suggesting that other pathways are required. L-proline activation of differentiation is mediated through metabolism and changes to intracellular metabolite levels, specifically reactive oxygen species. The implication of multiple signaling pathways in the process suggests a model in which the context of Src family kinase activation determines the outcomes of pluripotent cell differentiation. PMID:27723793

  4. The Nucleotide Synthesis Enzyme CAD Inhibits NOD2 Antibacterial Function in Human Intestinal Epithelial Cells

    Science.gov (United States)

    Richmond, Amy L.; Kabi, Amrita; Homer, Craig R.; García, Noemí Marina; Nickerson, Kourtney P.; NesvizhskiI, Alexey I.; Sreekumar, Arun; Chinnaiyan, Arul M.; Nuñez, Gabriel; McDonald, Christine

    2013-01-01

    BACKGROUND & AIMS Polymorphisms that reduce the function of nucleotide-binding oligomerization domain (NOD)2, a bacterial sensor, have been associated with Crohn’s disease (CD). No proteins that regulate NOD2 activity have been identified as selective pharmacologic targets. We sought to discover regulators of NOD2 that might be pharmacologic targets for CD therapies. METHODS Carbamoyl phosphate synthetase/ aspartate transcarbamylase/dihydroorotase (CAD) is an enzyme required for de novo pyrimidine nucleotide synthesis; it was identified as a NOD2-interacting protein by immunoprecipitation-coupled mass spectrometry. CAD expression was assessed in colon tissues from individuals with and without inflammatory bowel disease by immunohistochemistry. The interaction between CAD and NOD2 was assessed in human HCT116 intestinal epithelial cells by immunoprecipitation, immunoblot, reporter gene, and gentamicin protection assays. We also analyzed human cell lines that express variants of NOD2 and the effects of RNA interference, overexpression and CAD inhibitors. RESULTS CAD was identified as a NOD2-interacting protein expressed at increased levels in the intestinal epithelium of patients with CD compared with controls. Overexpression of CAD inhibited NOD2-dependent activation of nuclear factor κB and p38 mitogen-activated protein kinase, as well as intracellular killing of Salmonella. Reduction of CAD expression or administration of CAD inhibitors increased NOD2-dependent signaling and antibacterial functions of NOD2 variants that are and are not associated with CD. CONCLUSIONS The nucleotide synthesis enzyme CAD is a negative regulator of NOD2. The antibacterial function of NOD2 variants that have been associated with CD increased in response to pharmacologic inhibition of CAD. CAD is a potential therapeutic target for CD. PMID:22387394

  5. Interstitial cells of Cajal and Auerbach's plexus. A scanning electron microscopical study of guinea-pig small intestine

    DEFF Research Database (Denmark)

    Jessen, Harry; Thuneberg, Lars

    1991-01-01

    Anatomy, interstitial cells of Cajal, myenteric plexus, small intestine, guinea-pig, scanning electron microscopy......Anatomy, interstitial cells of Cajal, myenteric plexus, small intestine, guinea-pig, scanning electron microscopy...

  6. The recruitability and cell-cycle state of intestinal stem cells

    International Nuclear Information System (INIS)

    Potten, C.S.; Chadwick, C.; Ijiri, K.; Tsubouchi, S.; Hanson, W.R.

    1984-01-01

    Evidence is presented which suggests that the crypts of the small intestine contain at least two discrete but interdependent classes of stem cells, some with discrete cell kinetic properties and some with discrete radiation responses or radiosensitivities. Very low doses of X rays or gamma rays, or neutrons, kill a few cells in the stem cell regions of the crypt in a sensitive dose-dependent manner. Similar doses generate several different cell kinetic responses within either the clonogenic fraction or the cells at the stem cell position within the crypt. The cell kinetic responses range from apparent recruitment of G0 clonogenic cells into cycle, to a marked shortening of the average cell cycle of the cells at the stem cell position. It is suggested that the cell kinetic changes may be the consequence of the cell destruction

  7. PGE2 suppresses intestinal T cell function in thermal injury: a cause of enhanced bacterial translocation.

    Science.gov (United States)

    Choudhry, M A; Fazal, N; Namak, S Y; Haque, F; Ravindranath, T; Sayeed, M M

    2001-09-01

    Increased gut bacterial translocation in burn and trauma patients has been demonstrated in a number of previous studies, however, the mechanism for such an increased gut bacterial translocation in injured patients remains poorly understood. Utilizing a rat model of burn injury, in the present study we examined the role of intestinal immune defense by analyzing the T cell functions. We investigated if intestinal T cells dysfunction contributes to bacterial translocation after burn injury. Also our study determined if burn-mediated alterations in intestinal T cell functions are related to enhanced release of PGE2. Finally, we examined whether or not burn-related alterations in intestinal T cell function are due to inappropriate activation of signaling molecule P59fyn, which is required for T cell activation and proliferation. The results presented here showed an increase in gut bacterial accumulation in mesenteric lymph nodes after thermal injury. This was accompanied by a decrease in the intestinal T cell proliferative responses. Furthermore, the treatments of burn-injured animals with PGE2 synthesis blocker (indomethacin or NS398) prevented both the decrease in intestinal T cell proliferation and enhanced bacterial translocation. Finally, our data suggested that the inhibition of intestinal T cell proliferation could result via PGE2-mediated down-regulation of the T cell activation-signaling molecule P59fyn. These findings support a role of T cell-mediated immune defense against bacterial translocation in burn injury.

  8. JAK/STAT-1 Signaling Is Required for Reserve Intestinal Stem Cell Activation during Intestinal Regeneration Following Acute Inflammation

    Directory of Open Access Journals (Sweden)

    Camilla A. Richmond

    2018-01-01

    Full Text Available The intestinal epithelium serves as an essential barrier to the outside world and is maintained by functionally distinct populations of rapidly cycling intestinal stem cells (CBC ISCs and slowly cycling, reserve ISCs (r-ISCs. Because disruptions in the epithelial barrier can result from pathological activation of the immune system, we sought to investigate the impact of inflammation on ISC behavior during the regenerative response. In a murine model of αCD3 antibody-induced small-intestinal inflammation, r-ISCs proved highly resistant to injury, while CBC ISCs underwent apoptosis. Moreover, r-ISCs were induced to proliferate and functionally contribute to intestinal regeneration. Further analysis revealed that the inflammatory cytokines interferon gamma and tumor necrosis factor alpha led to r-ISC activation in enteroid culture, which could be blocked by the JAK/STAT inhibitor, tofacitinib. These results highlight an important role for r-ISCs in response to acute intestinal inflammation and show that JAK/STAT-1 signaling is required for the r-ISC regenerative response.

  9. Sphingosine kinase activity is not required for tumor cell viability.

    Directory of Open Access Journals (Sweden)

    Karen Rex

    Full Text Available Sphingosine kinases (SPHKs are enzymes that phosphorylate the lipid sphingosine, leading to the formation of sphingosine-1-phosphate (S1P. In addition to the well established role of extracellular S1P as a mitogen and potent chemoattractant, SPHK activity has been postulated to be an important intracellular regulator of apoptosis. According to the proposed rheostat theory, SPHK activity shifts the intracellular balance from the pro-apoptotic sphingolipids ceramide and sphingosine to the mitogenic S1P, thereby determining the susceptibility of a cell to apoptotic stress. Despite numerous publications with supporting evidence, a clear experimental confirmation of the impact of this mechanism on tumor cell viability in vitro and in vivo has been hampered by the lack of suitable tool reagents. Utilizing a structure based design approach, we developed potent and specific SPHK1/2 inhibitors. These compounds completely inhibited intracellular S1P production in human cells and attenuated vascular permeability in mice, but did not lead to reduced tumor cell growth in vitro or in vivo. In addition, siRNA experiments targeting either SPHK1 or SPHK2 in a large panel of cell lines failed to demonstrate any statistically significant effects on cell viability. These results show that the SPHK rheostat does not play a major role in tumor cell viability, and that SPHKs might not be attractive targets for pharmacological intervention in the area of oncology.

  10. Serratia marcescens is injurious to intestinal epithelial cells.

    Science.gov (United States)

    Ochieng, John B; Boisen, Nadia; Lindsay, Brianna; Santiago, Araceli; Ouma, Collins; Ombok, Maurice; Fields, Barry; Stine, O Colin; Nataro, James P

    2014-01-01

    Diarrhea causes substantial morbidity and mortality in children in low-income countries. Although numerous pathogens cause diarrhea, the etiology of many episodes remains unknown. Serratia marcescens is incriminated in hospital-associated infections, and HIV/AIDS associated diarrhea. We have recently found that Serratia spp. may be found more commonly in the stools of patients with diarrhea than in asymptomatic control children. We therefore investigated the possible enteric pathogenicity of S. marcescens in vitro employing a polarized human colonic epithelial cell (T84) monolayer. Infected monolayers were assayed for bacterial invasion, transepithelial electrical resistance (TEER), cytotoxicity, interleukin-8 (IL-8) release and morphological changes by scanning electron microscopy. We observed significantly greater epithelial cell invasion by S. marcescens compared to Escherichia coli strain HS (p = 0.0038 respectively). Cell invasion was accompanied by reduction in TEER and secretion of IL-8. Lactate dehydrogenase (LDH) extracellular concentration rapidly increased within a few hours of exposure of the monolayer to S. marcescens. Scanning electron microscopy of S. marcescens-infected monolayers demonstrated destruction of microvilli and vacuolization. Our results suggest that S. marcescens interacts with intestinal epithelial cells in culture and induces dramatic alterations similar to those produced by known enteric pathogens.

  11. Function of Bruton's tyrosine kinase during B cell development is partially independent of its catalytic activity

    NARCIS (Netherlands)

    S. Middendorp; G.M. Dingjan (Gemma); A. Maas (Alex); K. Dahlenborg; R.W. Hendriks (Rudi)

    2003-01-01

    textabstractThe Tec family member Bruton's tyrosine kinase (Btk) is a cytoplasmic protein tyrosine kinase that transduces signals from the pre-B and B cell receptor (BCR). Btk is involved in pre-B cell maturation by regulating IL-7 responsiveness, cell surface phenotype changes,

  12. SAM pointed domain ETS factor (SPDEF) regulates terminal differentiation and maturation of intestinal goblet cells

    Energy Technology Data Exchange (ETDEWEB)

    Noah, Taeko K.; Kazanjian, Avedis [Gastroenterology, Hepatology and Nutrition, Cincinnati Children' s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH (United States); Whitsett, Jeffrey [Developmental Biology, Cincinnati Children' s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH (United States); Neonatology and Pulmonary Biology, Cincinnati Children' s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH (United States); Shroyer, Noah F., E-mail: noah.shroyer@cchmc.org [Gastroenterology, Hepatology and Nutrition, Cincinnati Children' s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH (United States); Developmental Biology, Cincinnati Children' s Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, OH (United States)

    2010-02-01

    Background and Aims: SPDEF (also termed PDEF or PSE) is an ETS family transcription factor that regulates gene expression in the prostate and goblet cell hyperplasia in the lung. Spdef has been reported to be expressed in the intestine. In this paper, we identify an important role for Spdef in regulating intestinal epithelial cell homeostasis and differentiation. Methods: SPDEF expression was inhibited in colon cancer cells to determine its ability to control goblet cell gene activation. The effects of transgenic expression of Spdef on intestinal differentiation and homeostasis were determined. Results: In LS174T colon cancer cells treated with Notch/{gamma}-secretase inhibitor to activate goblet cell gene expression, shRNAs that inhibited SPDEF also repressed expression of goblet cell genes AGR2, MUC2, RETLNB, and SPINK4. Transgenic expression of Spdef caused the expansion of intestinal goblet cells and corresponding reduction in Paneth, enteroendocrine, and absorptive enterocytes. Spdef inhibited proliferation of intestinal crypt cells without induction of apoptosis. Prolonged expression of the Spdef transgene caused a progressive reduction in the number of crypts that expressed Spdef, consistent with its inhibitory effects on cell proliferation. Conclusions: Spdef was sufficient to inhibit proliferation of intestinal progenitors and induce differentiation into goblet cells; SPDEF was required for activation of goblet cell associated genes in vitro. These data support a model in which Spdef promotes terminal differentiation into goblet cells of a common goblet/Paneth progenitor.

  13. File list: NoD.Dig.10.AllAg.Intestinal_stem_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  14. File list: NoD.Dig.20.AllAg.Intestinal_stem_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  15. File list: InP.Dig.20.AllAg.Intestinal_stem_cells [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  16. Th17 Cell Induction by Adhesion of Microbes to Intestinal Epithelial Cells.

    Science.gov (United States)

    Atarashi, Koji; Tanoue, Takeshi; Ando, Minoru; Kamada, Nobuhiko; Nagano, Yuji; Narushima, Seiko; Suda, Wataru; Imaoka, Akemi; Setoyama, Hiromi; Nagamori, Takashi; Ishikawa, Eiji; Shima, Tatsuichiro; Hara, Taeko; Kado, Shoichi; Jinnohara, Toshi; Ohno, Hiroshi; Kondo, Takashi; Toyooka, Kiminori; Watanabe, Eiichiro; Yokoyama, Shin-Ichiro; Tokoro, Shunji; Mori, Hiroshi; Noguchi, Yurika; Morita, Hidetoshi; Ivanov, Ivaylo I; Sugiyama, Tsuyoshi; Nuñez, Gabriel; Camp, J Gray; Hattori, Masahira; Umesaki, Yoshinori; Honda, Kenya

    2015-10-08

    Intestinal Th17 cells are induced and accumulate in response to colonization with a subgroup of intestinal microbes such as segmented filamentous bacteria (SFB) and certain extracellular pathogens. Here, we show that adhesion of microbes to intestinal epithelial cells (ECs) is a critical cue for Th17 induction. Upon monocolonization of germ-free mice or rats with SFB indigenous to mice (M-SFB) or rats (R-SFB), M-SFB and R-SFB showed host-specific adhesion to small intestinal ECs, accompanied by host-specific induction of Th17 cells. Citrobacter rodentium and Escherichia coli O157 triggered similar Th17 responses, whereas adhesion-defective mutants of these microbes failed to do so. Moreover, a mixture of 20 bacterial strains, which were selected and isolated from fecal samples of a patient with ulcerative colitis on the basis of their ability to cause a robust induction of Th17 cells in the mouse colon, also exhibited EC-adhesive characteristics. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. The intestinal stem cell signature identifies colorectal cancer stem cells and predicts disease relapse

    NARCIS (Netherlands)

    Merlos-Suarez, A.; Barriga, F.M.; Jung, P.; Iglesias, M.; Cespedes, M.V.; Rossell, D.; Sevillano, M.; Hernando-Momblona, X.; da Silva-Diz, V.; Munoz, P.; Clevers, H.; Sancho, E.; Mangues, R.; Batlle, E.

    2011-01-01

    A frequent complication in colorectal cancer (CRC) is regeneration of the tumor after therapy. Here, we report that a gene signature specific for adult intestinal stem cells (ISCs) predicts disease relapse in CRC patients. ISCs are marked by high expression of the EphB2 receptor, which becomes

  18. Intestinal Stem Cell Niche Insights Gathered from Both In Vivo and Novel In Vitro Models

    Directory of Open Access Journals (Sweden)

    Nikolce Gjorevski

    2017-01-01

    Full Text Available Intestinal stem cells are located at the base of the crypts and are surrounded by a complex structure called niche. This environment is composed mainly of epithelial cells and stroma which provides signals that govern cell maintenance, proliferation, and differentiation. Understanding how the niche regulates stem cell fate by controlling developmental signaling pathways will help us to define how stem cells choose between self-renewal and differentiation and how they maintain their undifferentiated state. Tractable in vitro assay systems, which reflect the complexity of the in vivo situation but provide higher level of control, would likely be crucial in identifying new players and mechanisms controlling stem cell function. Knowledge of the intestinal stem cell niche gathered from both in vivo and novel in vitro models may help us improve therapies for tumorigenesis and intestinal damage and make autologous intestinal transplants a feasible clinical practice.

  19. Development and Characterization of a Human and Mouse Intestinal Epithelial Cell Monolayer Platform

    Directory of Open Access Journals (Sweden)

    Kenji Kozuka

    2017-12-01

    Full Text Available Summary: We describe the development and characterization of a mouse and human epithelial cell monolayer platform of the small and large intestines, with a broad range of potential applications including the discovery and development of minimally systemic drug candidates. Culture conditions for each intestinal segment were optimized by correlating monolayer global gene expression with the corresponding tissue segment. The monolayers polarized, formed tight junctions, and contained a diversity of intestinal epithelial cell lineages. Ion transport phenotypes of monolayers from the proximal and distal colon and small intestine matched the known and unique physiology of these intestinal segments. The cultures secreted serotonin, GLP-1, and FGF19 and upregulated the epithelial sodium channel in response to known biologically active agents, suggesting intact secretory and absorptive functions. A screen of over 2,000 pharmacologically active compounds for inhibition of potassium ion transport in the mouse distal colon cultures led to the identification of a tool compound. : Siegel and colleagues describe their development of a human and mouse intestinal epithelial cell monolayer platform that maintains the cellular, molecular, and functional characteristics of tissue for each intestinal segment. They demonstrate the platform's application to drug discovery by screening a library of over 2,000 compounds to identify an inhibitor of potassium ion transport in the mouse distal colon. Keywords: intestinal epithelium, organoids, monolayer, colon, small intestine, phenotype screening assays, enteroid, colonoid

  20. Transepithelial transport of flavanone in intestinal Caco-2 cell monolayers

    International Nuclear Information System (INIS)

    Kobayashi, Shoko; Konishi, Yutaka

    2008-01-01

    Our recent study [S. Kobayashi, S. Tanabe, M. Sugiyama, Y. Konishi, Transepithelial transport of hesperetin and hesperidin in intestinal Caco-2 cell monolayers, Biochim. Biophys. Acta, 1778 (2008) 33-41] shows that the mechanism of absorption of hesperetin involves both proton-coupled active transport and transcellular passive diffusion. Here, as well as analyzing the cell permeability of hesperetin, we also study the transport of other flavanones, naringenin and eriodictyol, using Caco-2 cell monolayers. Similar to hesperetin mentioned, naringenin and eriodictyol showed proton-coupled polarized transport in apical-to-basolateral direction in non-saturable manner, constant permeation in the apical-to-basolateral direction (J ap→bl ) irrespective of the transepithelial electrical resistance (TER), and preferable distribution into the basolateral side after apical loading in the presence of a proton gradient. Furthermore, the proton-coupled J ap→bl of hesperetin, naringenin and eriodictyol, were inhibited by substrates of the monocarboxylic acid transporter (MCT), such as benzoic acid, but not by ferulic acid. In contrast, both benzoic and ferulic acids have no stimulatory effect on J ap→bl of each flavanone by trans-stimulation analysis. These results indicates that proton-driven active transport is commonly participated in the absorption of flavanone in general, and that its transport is presumed to be unique other than MCT-mediated transport for absorption of phenolic acids (PAs), sodium-dependent MCT (SMCT) nor anion exchanger-mediated transport

  1. Antigen presentation by small intestinal epithelial cells uniquely enhances IFN-γ secretion from CD4{sup +} intestinal intraepithelial lymphocytes

    Energy Technology Data Exchange (ETDEWEB)

    Hatano, Ryo; Yamada, Kiyoshi; Iwamoto, Taku; Maeda, Nana; Emoto, Tetsuro; Shimizu, Makoto; Totsuka, Mamoru, E-mail: atotuka@mail.ecc.u-tokyo.ac.jp

    2013-06-14

    Highlights: •Small intestinal epithelial cells (sIECs). •sIECs are able to induce antigen specific proliferation of CD4{sup +} IELs. •sIECs induce markedly enhanced IFN-γ secretion by CD4{sup +} IELs. •Induction of enhanced IFN-γ secretion by sIECs is uniquely observed in CD4{sup +} IELs. -- Abstract: Small intestinal epithelial cells (sIECs) express major histocompatibility complex class II molecules even in a normal condition, and are known to function as antigen presenting cells (APCs) at least in vitro. These findings raised the possibility that sIECs play an important role in inducing immune responses against luminal antigens, especially those of intestinal intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs). We herein showed that antigenic stimulation with sIECs induced markedly greater secretion of interferon-gamma (IFN-γ) by CD4{sup +} IELs, but not interleukin (IL)-4, IL-10 and IL-17 although the proliferative response was prominently lower than that with T cell-depleted splenic APCs. In contrast, no enhanced IFN-γ secretion by CD4{sup +} LPLs and primed splenic CD4{sup +} T cells was observed when stimulated with sIECs. Taken together, these results suggest that sIECs uniquely activate CD4{sup +} IELs and induce remarkable IFN-γ secretion upon antigenic stimulation in vivo.

  2. Antigen presentation by small intestinal epithelial cells uniquely enhances IFN-γ secretion from CD4+ intestinal intraepithelial lymphocytes

    International Nuclear Information System (INIS)

    Hatano, Ryo; Yamada, Kiyoshi; Iwamoto, Taku; Maeda, Nana; Emoto, Tetsuro; Shimizu, Makoto; Totsuka, Mamoru

    2013-01-01

    Highlights: •Small intestinal epithelial cells (sIECs). •sIECs are able to induce antigen specific proliferation of CD4 + IELs. •sIECs induce markedly enhanced IFN-γ secretion by CD4 + IELs. •Induction of enhanced IFN-γ secretion by sIECs is uniquely observed in CD4 + IELs. -- Abstract: Small intestinal epithelial cells (sIECs) express major histocompatibility complex class II molecules even in a normal condition, and are known to function as antigen presenting cells (APCs) at least in vitro. These findings raised the possibility that sIECs play an important role in inducing immune responses against luminal antigens, especially those of intestinal intraepithelial lymphocytes (IELs) and lamina propria lymphocytes (LPLs). We herein showed that antigenic stimulation with sIECs induced markedly greater secretion of interferon-gamma (IFN-γ) by CD4 + IELs, but not interleukin (IL)-4, IL-10 and IL-17 although the proliferative response was prominently lower than that with T cell-depleted splenic APCs. In contrast, no enhanced IFN-γ secretion by CD4 + LPLs and primed splenic CD4 + T cells was observed when stimulated with sIECs. Taken together, these results suggest that sIECs uniquely activate CD4 + IELs and induce remarkable IFN-γ secretion upon antigenic stimulation in vivo

  3. Inhibition of nucleoside diphosphate kinase activity by in vitro phosphorylation by protein kinase CK2. Differential phosphorylation of NDP kinases in HeLa cells in culture

    DEFF Research Database (Denmark)

    Biondi, R M; Engel, M; Sauane, M

    1996-01-01

    that in vitro protein kinase CK2 catalyzed phosphorylation of human NDPK A inhibits its enzymatic activity by inhibiting the first step of its ping-pong mechanism of catalysis: its autophosphorylation. Upon in vivo 32P labeling of HeLa cells, we observed that both human NDPKs, A and B, were autophosphorylated...

  4. Interleukin-1 beta induced synthesis of protein kinase C-delta and protein kinase C-epsilon in EL4 thymoma cells: possible involvement of phosphatidylinositol 3-kinase.

    Science.gov (United States)

    Varley, C L; Royds, J A; Brown, B L; Dobson, P R

    2001-01-01

    We present evidence here that the proinflammatory cytokine, interleukin-1 beta (IL-1 beta) stimulates a significant increase in protein kinase C (PKC)-epsilon and PKC-delta protein levels and increases PKC-epsilon, but not PKC-delta, transcripts in EL4 thymoma cells. Incubation of EL4 cells with IL-1 beta induced protein synthesis of PKC-epsilon (6-fold increase) by 7 h and had a biphasic effect on PKC-delta levels with peaks at 4 h (2-fold increase) and 24 h (4-fold increase). At the level of mRNA, PKC-epsilon, but not PKC-delta levels, were induced after incubation of EL4 cells with IL-1 beta. The signalling mechanisms utilized by IL-1 beta to induce the synthesis of these PKC isoforms were investigated. Two phosphatidylinositol (PI) 3-kinase-specific inhibitors, wortmannin and LY294002, inhibited IL-1 beta-induced synthesis of PKC-epsilon. However, the PI 3-kinase inhibitors had little effect on the IL-1 beta-induced synthesis of PKC-delta in these cells. Our results indicate that IL-1 beta induced both PKC-delta and PKC-epsilon expression over different time periods. Furthermore, our evidence suggests that IL-1 beta induction of PKC-epsilon, but not PKC-delta, may occur via the PI 3-kinase pathway. Copyright 2001 S. Karger AG, Basel

  5. De Novo Formation of Insulin-Producing “Neo-β Cell Islets” from Intestinal Crypts

    Directory of Open Access Journals (Sweden)

    Yi-Ju Chen

    2014-03-01

    Full Text Available The ability to interconvert terminally differentiated cells could serve as a powerful tool for cell-based treatment of degenerative diseases, including diabetes mellitus. To determine which, if any, adult tissues are competent to activate an islet β cell program, we performed an in vivo screen by expressing three β cell “reprogramming factors” in a wide spectrum of tissues. We report that transient intestinal expression of these factors—Pdx1, MafA, and Ngn3 (PMN—promotes rapid conversion of intestinal crypt cells into endocrine cells, which coalesce into “neoislets” below the crypt base. Neoislet cells express insulin and show ultrastructural features of β cells. Importantly, intestinal neoislets are glucose-responsive and able to ameliorate hyperglycemia in diabetic mice. Moreover, PMN expression in human intestinal “organoids” stimulates the conversion of intestinal epithelial cells into β-like cells. Our results thus demonstrate that the intestine is an accessible and abundant source of functional insulin-producing cells.

  6. RNAi screen reveals host cell kinases specifically involved in Listeria monocytogenes spread from cell to cell.

    Directory of Open Access Journals (Sweden)

    Ryan Chong

    Full Text Available Intracellular bacterial pathogens, such as Listeria monocytogenes and Rickettsia conorii display actin-based motility in the cytosol of infected cells and spread from cell to cell through the formation of membrane protrusions at the cell cortex. Whereas the mechanisms supporting cytosolic actin-based motility are fairly well understood, it is unclear whether specific host factors may be required for supporting the formation and resolution of membrane protrusions. To address this gap in knowledge, we have developed high-throughput fluorescence microscopy and computer-assisted image analysis procedures to quantify pathogen spread in human epithelial cells. We used the approach to screen a siRNA library covering the human kinome and identified 7 candidate kinases whose depletion led to severe spreading defects in cells infected with L. monocytogenes. We conducted systematic validation procedures with redundant silencing reagents and confirmed the involvement of the serine/threonine kinases, CSNK1A1 and CSNK2B. We conducted secondary assays showing that, in contrast with the situation observed in CSNK2B-depleted cells, L. monocytogenes formed wild-type cytosolic tails and displayed wild-type actin-based motility in the cytosol of CSNK1A1-depleted cells. Furthermore, we developed a protrusion formation assay and showed that the spreading defect observed in CSNK1A1-depleted cells correlated with the formation of protrusion that did not resolve into double-membrane vacuoles. Moreover, we developed sending and receiving cell-specific RNAi procedures and showed that CSNK1A was required in the sending cells, but was dispensable in the receiving cells, for protrusion resolution. Finally, we showed that the observed defects were specific to Listeria monocytogenes, as Rickettsia conorii displayed wild-type cell-to-cell spread in CSNK1A1- and CSNK2B-depleted cells. We conclude that, in addition to the specific host factors supporting cytosolic actin

  7. Genome-wide analysis of CDX2 binding in intestinal epithelial cells (Caco-2)

    DEFF Research Database (Denmark)

    Boyd, Mette; Hansen, Morten; Jensen, Tine G K

    2010-01-01

    The CDX2 transcription factor is known to play a crucial role in inhibiting proliferation, promoting differentiation and the expression of intestinal specific genes in intestinal cells. The overall effect of CDX2 in intestinal cells has previously been investigated in conditional knock-out mice......, revealing a critical role of CDX2 in the formation of the normal intestinal identity. The identification of direct targets of transcription factors is a key problem in the study of gene regulatory networks. The ChIP-seq technique combines chromatin immunoprecipitation (ChIP) with next generation sequencing...... resulting in a high throughput experimental method of identifying direct targets of specific transcription factors. The method was applied to CDX2, leading to the identification of the direct binding of CDX2 to several known and novel target genes in the intestinal cell. Examination of the transcript levels...

  8. Effects of Butyltins (BTs) on Mitogen-Activated-Protein Kinase Kinase Kinase (MAP3K) and Ras Activity in Human Natural Killer Cells

    Science.gov (United States)

    Celada, Lindsay J.; Whalen, Margaret M.

    2013-01-01

    Butyltins (BTs) contaminate the environment and are found in human blood. BTs, tributyltin (TBT) and dibutyltin (DBT), diminish the cytotoxic function and levels of key proteins of human natural killer (NK) cells. NK cells are an initial immune defense against tumors, virally-infected cells and antibody-coated cells and thus critical to human health. The signaling pathways that regulate NK cell functions include mitogen-activated protein kinases (MAPKs). Studies have shown that exposure to BTs leads to the activation of specific MAPKs and MAPK kinases (MAP2Ks) in human NK cells. MAP2K kinases (MAP3Ks) are upstream activators of MAP2Ks, which then activate MAPKs. The current study examined if BT-induced activation of MAP3Ks was responsible for MAP2K and thus, MAPK activation. This study examines the effects of TBT and DBT on the total levels of two MAP3Ks, c-Raf and ASK1, as well as activating and inhibitory phosphorylation sites on these MAP3Ks. In addition, the immediate upstream activator of c-Raf, Ras, was examined for BT-induced alterations. Our results show significant activation of the MAP3K, c-Raf, in human NK cells within 10 minutes of TBT exposure and the MAP3K, ASK1, after one hour exposures to TBT. In addition, our results suggest that both TBT and DBT are impacting the regulation of c-Raf. PMID:24038145

  9. Interleukin-17 is a potent immuno-modulator and regulator of normal human intestinal epithelial cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Schwartz, S [Children' s Hospital, Mucosal Immunology Laboratory, University of Bonn, Bonn (Germany); Beaulieu, J F [Department of Cell Biology/Anatomy, University of Sherbrooke, Sherbrooke (Canada); Ruemmele, F M [Children' s Hospital, Mucosal Immunology Laboratory, University of Bonn, Bonn (Germany) and INSERM EMI0212, Faculte de Medecine Necker, University Paris V, Paediatric Gastroenterology Unit, Department of Paediatrics, Hopital Necker-Enfants Malades, Assistance-Publique-Hopitaux de Paris, Paris (France)

    2005-11-18

    Upregulation of the T-cell derived cytokine interleukin (IL-17) was reported in the inflamed intestinal mucosa of patients with inflammatory bowel disorders. In this study, we analyzed the effect of IL-17 on human intestinal epithelial cell (HIEC) turnover and functions. Proliferation and apoptosis in response to IL-17 was monitored in HIEC (cell counts, [{sup 3}H]thymidine incorporation method, and annexinV-PI-apoptosis assay). Signalling pathways were analyzed by Western blots, electromobility shift assay, and immunofluorescence studies. IL-17 proved to be a potent inhibitor of HIEC proliferation without any pro-apoptotic/necrotic effect. The growth inhibitory effect of IL-17 was mediated via the p38 stress kinase. Consequently, the p38-SAPkinase-inhibitor SB203580 abrogated this anti-mitotic effect. In parallel, IL-17 provoked the degradation of I{kappa}B{alpha}, allowing nuclear translocation of the p65 NF-{kappa}B subunit and induction of the NF-{kappa}B-controlled genes IL-6 and -8. IL-17 potently blocks epithelial cell turnover while at the same time amplifying an inflammatory response in a positive feedback manner.

  10. Lipoteichoic Acid of Probiotic Lactobacillus plantarum Attenuates Poly I:C-Induced IL-8 Production in Porcine Intestinal Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Kyoung Whun Kim

    2017-09-01

    Full Text Available Probiotics in livestock feed supplements are considered a replacement for antibiotics that enhance gastrointestinal immunity. Although bacterial cell wall components have been proposed to be associated with probiotic function, little evidence demonstrates that they are responsible for probiotic functions in livestock. The present study demonstrated that lipoteichoic acid (LTA of Lactobacillus plantarum (Lp.LTA confers anti-inflammatory responses in porcine intestinal epithelial cell line, IPEC-J2. A synthetic analog of viral double-stranded RNA, poly I:C, dose-dependently induced IL-8 production at the mRNA and protein levels in IPEC-J2 cells. Lp.LTA, but not lipoprotein or peptidoglycan from L. plantarum, exclusively suppressed poly I:C-induced IL-8 production. Compared with LTAs from other probiotic Lactobacillus strains including L. delbrueckii, L. sakei, and L. rhamnosus GG, Lp.LTA had higher potential to suppress poly I:C-induced IL-8 production. Dealanylated or deacylated Lp.LTA did not suppress poly I:C-induced IL-8 production, suggesting that D-alanine and lipid moieties in the Lp.LTA structure were responsible for the inhibition. Furthermore, Lp.LTA attenuated the phosphorylation of ERK and p38 kinase as well as the activation of NF-κB, resulting in decreased IL-8 production. Taken together, these results suggest that Lp.LTA acts as an effector molecule to inhibit viral pathogen-induced inflammatory responses in porcine intestinal epithelial cells.

  11. Further characterization of protein kinase C in mouse mast cells

    International Nuclear Information System (INIS)

    White, J.R.; Ishizaka, T.

    1986-01-01

    Bridging of cell-bound IgE antibody molecules on colony stimulating factor dependent mouse mast cell line (PT-18) cells by multivalent antigen induces the mobilization and uptake of Ca 2+ monitored by Quin-2 and the production of diacylglycerol. Exposure of the sensitized cells to antigen also induces a substantial increase in protein kinase C (PKC) activity in the plasma membrane (340 units to 1375 units: 1 unit = 1 pmol of 32 P incorporated into Histone H-1/min/10 7 cells), within 30 seconds. There is also an increase in 3 H phorbol-12, 13-dibutyrate ( 3 H-PDB) binding which parallels the increase in PKC activity both in kinetics and antigen dose dependency. Determination of K/sub m/ and V/sub max/ for PKC revealed no difference between the cytosolic and membranous forms of PKC. Partial purification of PKC from the membrane of sensitized mast cells which had been labeled with 32 P and stimulated with DNP-HSA revealed a protein of 80-84,000 molecular weight, which migrated on polyacrylamide gel electrophoresis just above an authentic standard of PKC purified from rat brain. Treatment of the PKC from mouse mast cell membrane with alkaline phosphatase resulted in a reduction of phosphorylating activity and bindability of 3 H-PDB. In conclusion, the authors speculate that activation of mouse mast cells by cross-linking IgE results in the phosphorylation of a silent-pool of PKC converting it from an inactive state to an activated form

  12. Selective Cyclin-Dependent Kinase Inhibitors Discriminating between Cell Cycle and Transcriptional Kinases Future Reality or Utopia?

    Czech Academy of Sciences Publication Activity Database

    Wesierska-Gadek, J.; Kryštof, Vladimír

    2009-01-01

    Roč. 1171, - (2009), s. 228-241 ISSN 0077-8923 R&D Projects: GA ČR GA204/08/0511 Institutional research plan: CEZ:AV0Z50380511 Keywords : cell cycle * CYC202 * cyclin-dependent kinase Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.670, year: 2009

  13. Maintaining glycogen synthase kinase-3 activity is critical for mTOR kinase inhibitors to inhibit cancer cell growth.

    Science.gov (United States)

    Koo, Junghui; Yue, Ping; Gal, Anthony A; Khuri, Fadlo R; Sun, Shi-Yong

    2014-05-01

    mTOR kinase inhibitors that target both mTORC1 and mTORC2 are being evaluated in cancer clinical trials. Here, we report that glycogen synthase kinase-3 (GSK3) is a critical determinant for the therapeutic response to this class of experimental drugs. Pharmacologic inhibition of GSK3 antagonized their suppressive effects on the growth of cancer cells similarly to genetic attenuation of GSK3. Conversely, expression of a constitutively activated form of GSK3β sensitized cancer cells to mTOR inhibition. Consistent with these findings, higher basal levels of GSK3 activity in a panel of human lung cancer cell lines correlated with more efficacious responses. Mechanistic investigations showed that mTOR kinase inhibitors reduced cyclin D1 levels in a GSK3β-dependent manner, independent of their effects on suppressing mTORC1 signaling and cap binding. Notably, selective inhibition of mTORC2 triggered proteasome-mediated cyclin D1 degradation, suggesting that mTORC2 blockade is responsible for GSK3-dependent reduction of cyclin D1. Silencing expression of the ubiquitin E3 ligase FBX4 rescued this reduction, implicating FBX4 in mediating this effect of mTOR inhibition. Together, our findings define a novel mechanism by which mTORC2 promotes cell growth, with potential implications for understanding the clinical action of mTOR kinase inhibitors. ©2014 AACR.

  14. Butyrate attenuates lipopolysaccharide-induced inflammation in intestinal cells and Crohn's mucosa through modulation of antioxidant defense machinery.

    Directory of Open Access Journals (Sweden)

    Ilaria Russo

    Full Text Available Oxidative stress plays an important role in the pathogenesis of inflammatory bowel disease (IBD, including Crohn's disease (CrD. High levels of Reactive Oxygen Species (ROS induce the activation of the redox-sensitive nuclear transcription factor kappa-B (NF-κB, which in turn triggers the inflammatory mediators. Butyrate decreases pro-inflammatory cytokine expression by the lamina propria mononuclear cells in CrD patients via inhibition of NF-κB activation, but how it reduces inflammation is still unclear. We suggest that butyrate controls ROS mediated NF-κB activation and thus mucosal inflammation in intestinal epithelial cells and in CrD colonic mucosa by triggering intracellular antioxidant defense systems. Intestinal epithelial Caco-2 cells and colonic mucosa from 14 patients with CrD and 12 controls were challenged with or without lipopolysaccaride from Escherichia coli (EC-LPS in presence or absence of butyrate for 4 and 24 h. The effects of butyrate on oxidative stress, p42/44 MAP kinase phosphorylation, p65-NF-κB activation and mucosal inflammation were investigated by real time PCR, western blot and confocal microscopy. Our results suggest that EC-LPS challenge induces a decrease in Gluthation-S-Transferase-alpha (GSTA1/A2 mRNA levels, protein expression and catalytic activity; enhanced levels of ROS induced by EC-LPS challenge mediates p65-NF-κB activation and inflammatory response in Caco-2 cells and in CrD colonic mucosa. Furthermore butyrate treatment was seen to restore GSTA1/A2 mRNA levels, protein expression and catalytic activity and to control NF-κB activation, COX-2, ICAM-1 and the release of pro-inflammatory cytokine. In conclusion, butyrate rescues the redox machinery and controls the intracellular ROS balance thus switching off EC-LPS induced inflammatory response in intestinal epithelial cells and in CrD colonic mucosa.

  15. CD34+ mesenchymal cells are a major component of the intestinal stem cells niche at homeostasis and after injury.

    Science.gov (United States)

    Stzepourginski, Igor; Nigro, Giulia; Jacob, Jean-Marie; Dulauroy, Sophie; Sansonetti, Philippe J; Eberl, Gérard; Peduto, Lucie

    2017-01-24

    The intestinal epithelium is continuously renewed by intestinal epithelial stem cells (IESCs) positioned at the base of each crypt. Mesenchymal-derived factors are essential to maintain IESCs; however, the cellular composition and development of such mesenchymal niche remains unclear. Here, we identify pericryptal CD34 + Gp38 + αSMA - mesenchymal cells closely associated with Lgr5 + IESCs. We demonstrate that CD34 + Gp38 + cells are the major intestinal producers of the niche factors Wnt2b, Gremlin1, and R-spondin1, and are sufficient to promote maintenance of Lgr5 + IESCs in intestinal organoids, an effect mainly mediated by Gremlin1. CD34 + Gp38 + cells develop after birth in the intestinal submucosa and expand around the crypts during the third week of life in mice, independently of the microbiota. We further show that pericryptal CD34 + gp38 + cells are rapidly activated by intestinal injury, up-regulating niche factors Gremlin1 and R-spondin1 as well as chemokines, proinflammatory cytokines, and growth factors with key roles in gut immunity and tissue repair, including IL-7, Ccl2, Ptgs2, and Amphiregulin. Our results indicate that CD34 + Gp38 + mesenchymal cells are programmed to develop in the intestine after birth to constitute a specialized microenvironment that maintains IESCs at homeostasis and contribute to intestinal inflammation and repair after injury.

  16. In Inflamed Intestinal Tissues and Epithelial Cells, Interleukin 22 Signaling Increases Expression of H19 Long Noncoding RNA, Which Promotes Mucosal Regeneration.

    Science.gov (United States)

    Geng, Hua; Bu, Heng-Fu; Liu, Fangyi; Wu, Longtao; Pfeifer, Karl; Chou, Pauline M; Wang, Xiao; Sun, Jiaren; Lu, Lu; Pandey, Ashutosh; Bartolomei, Marisa S; De Plaen, Isabelle G; Wang, Peng; Yu, Jindan; Qian, Jiaming; Tan, Xiao-Di

    2018-04-03

    expression. Exposure of IECs to interleukin (IL) 22 increased levels of H19 lncRNA with time and dose, which required STAT3 and protein kinase A activity. IL22 induced expression of H19 in mouse intestinal epithelial organoids within 6 hours. Exposure to IL22 increased growth of intestinal epithelial organoids derived from control mice, but not H19 ΔEx1/+ mice. Overexpression of H19 in HT-29 cells increased their proliferation. Intestinal mucosa healed more slowly after withdrawal of DSS from H19 ΔEx1/+ mice vs control mice. Crypt epithelial cells from H19 ΔEx1/+ mice proliferated more slowly than those from control mice after exposure to LPS. H19 lncRNA bound to p53 and microRNAs that inhibit cell proliferation, including microRNA 34a and let-7; H19 lncRNA binding blocked their function, leading to increased expression of genes that promote regeneration of the epithelium. The level of lncRNA H19 is increased in inflamed intestinal tissues from mice and patients. The inflammatory cytokine IL22 induces expression of H19 in IECs, which is required for intestinal epithelial proliferation and mucosal healing. H19 lncRNA appears to inhibit p53 protein and microRNA 34a and let-7 to promote proliferation of IECs and epithelial regeneration. Copyright © 2018 AGA Institute. Published by Elsevier Inc. All rights reserved.

  17. PIM kinases as potential therapeutic targets in a subset of peripheral T cell lymphoma cases.

    Directory of Open Access Journals (Sweden)

    Esperanza Martín-Sánchez

    Full Text Available Currently, there is no efficient therapy for patients with peripheral T cell lymphoma (PTCL. The Proviral Integration site of Moloney murine leukemia virus (PIM kinases are important mediators of cell survival. We aimed to determine the therapeutic value of PIM kinases because they are overexpressed in PTCL patients, T cell lines and primary tumoral T cells. PIM kinases were inhibited genetically (using small interfering and short hairpin RNAs and pharmacologically (mainly with the pan-PIM inhibitor (PIMi ETP-39010 in a panel of 8 PTCL cell lines. Effects on cell viability, apoptosis, cell cycle, key proteins and gene expression were evaluated. Individual inhibition of each of the PIM genes did not affect PTCL cell survival, partially because of a compensatory mechanism among the three PIM genes. In contrast, pharmacological inhibition of all PIM kinases strongly induced apoptosis in all PTCL cell lines, without cell cycle arrest, in part through the induction of DNA damage. Therefore, pan-PIMi synergized with Cisplatin. Importantly, pharmacological inhibition of PIM reduced primary tumoral T cell viability without affecting normal T cells ex vivo. Since anaplastic large cell lymphoma (ALK+ ALCL cell lines were the most sensitive to the pan-PIMi, we tested the simultaneous inhibition of ALK and PIM kinases and found a strong synergistic effect in ALK+ ALCL cell lines. Our findings suggest that PIM kinase inhibition could be of therapeutic value in a subset of PTCL, especially when combined with ALK inhibitors, and might be clinically beneficial in ALK+ ALCL.

  18. Catechol Groups Enable Reactive Oxygen Species Scavenging-Mediated Suppression of PKD-NFkappaB-IL-8 Signaling Pathway by Chlorogenic and Caffeic Acids in Human Intestinal Cells

    Directory of Open Access Journals (Sweden)

    Hee Soon Shin

    2017-02-01

    Full Text Available Chlorogenic acid (CHA and caffeic acid (CA are phenolic compounds found in coffee, which inhibit oxidative stress-induced interleukin (IL-8 production in intestinal epithelial cells, thereby suppressing serious cellular injury and inflammatory intestinal diseases. Therefore, we investigated the anti-inflammatory mechanism of CHA and CA, both of which inhibited hydrogen peroxide (H2O2-induced IL-8 transcriptional activity. They also significantly suppressed nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB transcriptional activity, nuclear translocation of the p65 subunit, and phosphorylation of IκB kinase (IKK. Additionally, upstream of IKK, protein kinase D (PKD was also suppressed. Finally, we found that they scavenged H2O2-induced reactive oxygen species (ROS and the functional moiety responsible for the anti-inflammatory effects of CHA and CA was the catechol group. Therefore, we conclude that the presence of catechol groups in CHA and CA allows scavenging of intracellular ROS, thereby inhibiting H2O2-induced IL-8 production via suppression of PKD-NF-κB signaling in human intestinal epithelial cells.

  19. Protein kinase C, focal adhesions and the regulation of cell migration

    DEFF Research Database (Denmark)

    Fogh, Betina S; Multhaupt, Hinke A B; Couchman, John Robert

    2014-01-01

    in their intracellular compartment. Among these are tyrosine kinases, which have received a great deal of attention, whereas the serine/threonine kinase protein kinase C has received much less. Here the status of protein kinase C in focal adhesions and cell migration is reviewed, together with discussion of its roles...... and adhesion turnover. Focal adhesions, or focal contacts, are widespread organelles at the cell-matrix interface. They arise as a result of receptor interactions with matrix ligands, together with clustering. Recent analysis shows that focal adhesions contain a very large number of protein components...

  20. Urokinase and the intestinal mucosa: evidence for a role in epithelial cell turnover

    Science.gov (United States)

    Gibson, P; Birchall, I; Rosella, O; Albert, V; Finch, C; Barkla, D; Young, G

    1998-01-01

    Background—The functions of urokinase in intestinal epithelia are unknown. 
Aims—To determine the relation of urokinase expressed by intestinal epithelial cells to their position in the crypt-villus/surface axis and of mucosal urokinase activity to epithelial proliferative kinetics in the distal colon. 
Methods—Urokinase expression was examined immunohistochemically in human intestinal mucosa. Urokinase activity was measured colorimetrically in epithelial cells isolated sequentially from the crypt-villus axis of the rat small intestine. In separate experiments, urokinase activity and epithelial kinetics (measured stathmokinetically) were measured in homogenates of distal colonic mucosa of 14 groups of eight rats fed diets known to alter epithelial turnover. 
Results—From the crypt base, an ascending gradient of expression and activity of urokinase was associated with the epithelial cells. Median mucosal urokinase activities in each of the dietary groups of rats correlated positively with autologous median number of metaphase arrests per crypt (r=0.68; p<0.005) and per 100 crypt cells (r=0.75; p<0.001), but not with crypt column height. 
Conclusions—Localisation of an enzyme capable of leading to digestion of cell substratum in the region where cells are loosely attached to their basement membrane, and the association of its activity with indexes of cell turnover, suggest a role for urokinase in facilitating epithelial cell loss in the intestine. 

 Keywords: urokinase; intestinal epithelium; colon; epithelial proliferation PMID:9824347

  1. Distinct and Overlapping Functions of TEC Kinase and BTK in B Cell Receptor Signaling.

    Science.gov (United States)

    de Bruijn, Marjolein J W; Rip, Jasper; van der Ploeg, Esmee K; van Greuningen, Lars W; Ta, Van T B; Kil, Laurens P; Langerak, Anton W; Rimmelzwaan, Guus F; Ellmeier, Wilfried; Hendriks, Rudi W; Corneth, Odilia B J

    2017-04-15

    The Tec tyrosine kinase is expressed in many cell types, including hematopoietic cells, and is a member of the Tec kinase family that also includes Btk. Although the role of Btk in B cells has been extensively studied, the role of Tec kinase in B cells remains largely unclear. It was previously shown that Tec kinase has the ability to partly compensate for loss of Btk activity in B cell differentiation, although the underlying mechanism is unknown. In this study, we confirm that Tec kinase is not essential for normal B cell development when Btk is present, but we also found that Tec-deficient mature B cells showed increased activation, proliferation, and survival upon BCR stimulation, even in the presence of Btk. Whereas Tec deficiency did not affect phosphorylation of phospholipase Cγ or Ca 2+ influx, it was associated with significantly increased activation of the intracellular Akt/S6 kinase signaling pathway upon BCR and CD40 stimulation. The increased S6 kinase phosphorylation in Tec-deficient B cells was dependent on Btk kinase activity, as ibrutinib treatment restored pS6 to wild-type levels, although Btk protein and phosphorylation levels were comparable to controls. In Tec-deficient mice in vivo, B cell responses to model Ags and humoral immunity upon influenza infection were enhanced. Moreover, aged mice lacking Tec kinase developed a mild autoimmune phenotype. Taken together, these data indicate that in mature B cells, Tec and Btk may compete for activation of the Akt signaling pathway, whereby the activating capacity of Btk is limited by the presence of Tec kinase. Copyright © 2017 by The American Association of Immunologists, Inc.

  2. Transcriptional regulation of the human Na+/H+ exchanger NHE3 by serotonin in intestinal epithelial cells

    International Nuclear Information System (INIS)

    Amin, Md Ruhul; Ghannad, Leda; Othman, Ahmad; Gill, Ravinder K.; Dudeja, Pradeep K.; Ramaswamy, Krishnamurthy; Malakooti, Jaleh

    2009-01-01

    Serotonin (5-HT) decreases NHE2 and NHE3 activities under acute conditions in human intestinal epithelial cells. Here, we have investigated the effects of 5-HT on expression of the human NHE3 gene and the mechanisms underlying its transcriptional regulation in differentiated C2BBe1 cells. Treatment of the human intestinal epithelial cell line, C2BBe1, with 5-HT (20 μM) resulted in a significant decrease in NHE3 mRNA and protein expression. In transient transfection studies, 5-HT repressed the NHE3 promoter activity by ∼55%. The repression of the NHE3 promoter activity in response to 5-HT was accompanied by reduced DNA-binding activity of transcription factors Sp1 and Sp3 to the NHE3 promoter without alteration in their nuclear levels. Pharmacological inhibitors of protein kinase C reversed the inhibitory effect of 5-HT on the promoter activity. Our data indicate that 5-HT suppresses the transcriptional activity of the NHE3 promoter and this effect may be mediated by PKCα and modulation of DNA-binding affinities of Sp1 and Sp3.

  3. Protein Kinase G facilitates EGFR-mediated cell death in MDA-MB-468 cells

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Nicole M.; Ceresa, Brian P., E-mail: brian.ceresa@louisville.edu

    2016-08-15

    The Epidermal Growth Factor Receptor (EGFR) is a transmembrane receptor tyrosine kinase with critical implications in cell proliferation, migration, wound healing and the regulation of apoptosis. However, the EGFR has been shown to be hyper-expressed in a number of human malignancies. The MDA-MB-468 metastatic breast cell line is one example of this. This particular cell line hyper-expresses the EGFR and undergoes EGFR-mediated apoptosis in response to EGF ligand. The goal of this study was to identify the kinases that could be potential intermediates for the EGFR-mediated induction of apoptosis intracellularly. After identifying Cyclic GMP-dependent Protein Kinase G (PKG) as a plausible intermediate, we wanted to determine the temporal relationship of these two proteins in the induction of apoptosis. We observed a dose-dependent decrease in MDA-MB-468 cell viability, which was co-incident with increased PKG activity as measured by VASPSer239 phosphorylation. In addition, we observed a dose dependent decrease in cell viability, as well as an increase in apoptosis, in response to two different PKG agonists, 8-Bromo-cGMP and 8-pCPT-cGMP. MDA-MB-468 cells with reduced PKG activity had attenuated EGFR-mediated apoptosis. These findings indicate that PKG does not induce cell death via transphosphorylation of the EGFR. Instead, PKG activity occurs following EGFR activation. Together, these data indicate PKG as an intermediary in EGFR-mediated cell death, likely via apoptotic pathway.

  4. Signaling by Kit protein-tyrosine kinase--the stem cell factor receptor.

    Science.gov (United States)

    Roskoski, Robert

    2005-11-11

    Signaling by stem cell factor and Kit, its receptor, plays important roles in gametogenesis, hematopoiesis, mast cell development and function, and melanogenesis. Moreover, human and mouse embryonic stem cells express Kit transcripts. Stem cell factor exists as both a soluble and a membrane-bound glycoprotein while Kit is a receptor protein-tyrosine kinase. The complete absence of stem cell factor or Kit is lethal. Deficiencies of either produce defects in red and white blood cell production, hypopigmentation, and sterility. Gain-of-function mutations of Kit are associated with several human neoplasms including acute myelogenous leukemia, gastrointestinal stromal tumors, and mastocytomas. Kit consists of an extracellular domain, a transmembrane segment, a juxtamembrane segment, and a protein kinase domain that contains an insert of about 80 amino acid residues. Binding of stem cell factor to Kit results in receptor dimerization and activation of protein kinase activity. The activated receptor becomes autophosphorylated at tyrosine residues that serve as docking sites for signal transduction molecules containing SH2 domains. The adaptor protein APS, Src family kinases, and Shp2 tyrosyl phosphatase bind to phosphotyrosine 568. Shp1 tyrosyl phosphatase and the adaptor protein Shc bind to phosphotyrosine 570. C-terminal Src kinase homologous kinase and the adaptor Shc bind to both phosphotyrosines 568 and 570. These residues occur in the juxtamembrane segment of Kit. Three residues in the kinase insert domain are phosphorylated and attract the adaptor protein Grb2 (Tyr703), phosphatidylinositol 3-kinase (Tyr721), and phospholipase Cgamma (Tyr730). Phosphotyrosine 900 in the distal kinase domain binds phosphatidylinositol 3-kinase which in turn binds the adaptor protein Crk. Phosphotyrosine 936, also in the distal kinase domain, binds the adaptor proteins APS, Grb2, and Grb7. Kit has the potential to participate in multiple signal transduction pathways as a result of

  5. The role of Protein Kinase Cη in T cell biology

    Directory of Open Access Journals (Sweden)

    Nicholas R.J. Gascoigne

    2012-06-01

    Full Text Available Protein kinase Cη (PKCη is a member of the novel PKC subfamily, which also includes δ, ε, and θ isoforms. Compared to the other novel PKCs, the function of PKCη in the immune system is largely unknown. Several studies have started to reveal the role of PKCη, particularly in T cells. PKCη is highly expressed in T cells, and is upregulated during thymocyte positive selection. Interestingly, like the θ isoform, PKCη is also recruited to the immunological synapse that is formed between a T cell and an antigen-presenting cell. However, unlike PKCθ, which becomes concentrated to the central region of the synapse, PKCη remains in a diffuse pattern over the whole area of the synapse, suggesting distinctive roles of these two isoforms in signal transduction. Although PKCη is dispensable for thymocyte development, further analysis of PKCη− or PKCθ−deficient and double knockout mice revealed the redundancy of these two isoforms in thymocyte development. In contrast, PKCη rather than PKCθ, plays an important role for T cell homeostatic proliferation, which requires recognition of self-antigen. Another piece of evidence demonstrating that PKCη and PKCθ have isoform specific as well as redundant roles come from the analysis of CD4 to CD8 T cell ratios in the periphery of these knockout mice. Deficiency in PKCη or PKCθ had opposing effects as PKCη knockout mice had a higher ratio of CD4 to CD8 T cells compared to that of wild-type mice, whereas PKCθ-deficient mice had a lower ratio. Biochemical studies showed that calcium flux and NFκB translocation is impaired in PKCη-deficient T cells upon TCR crosslinking stimulation, a character shared with PKCθ-deficient T cells. However, unlike the case with PKCθ, the mechanistic study of PKCη is at early stage and the signaling pathways involving PKCη, at least in T cells, are essentially unknown. In this review, we will cover the topics mentioned above as well as provide some

  6. Mechanisms of Cell Polarity-Controlled Epithelial Homeostasis and Immunity in the Intestine

    NARCIS (Netherlands)

    Klunder, Leon J.; Faber, Klaas Nico; Dijkstra, Gerard; van IJzendoorn, Sven C. D.

    Intestinal epithelial cell polarity is instrumental to maintain epithelial homeostasis and balance communications between the gut lumen and bodily tissue, thereby controlling the defense against gastrointestinal pathogens and maintenance of immune tolerance to commensal bacteria. In this review, we

  7. Indian hedgehog regulates intestinal stem cell fate through epithelial-mesenchymal interactions during development

    NARCIS (Netherlands)

    Kosinski, C.; Stange, D.E.; Xu, C.; Chan, A.S.; Ho, C.; Yuen, S.T.; Mifflin, R.C.; Powell, D.W.; Clevers, H.; Leung, S.Y.; Chen, X.N.

    2010-01-01

    BACKGROUND & AIMS: Intestinal stem cells (ISCs) are regulated by the mesenchymal environment via physical interaction and diffusible factors. We examined the role of Indian hedgehog (Ihh) in mesenchymal organization and the mechanisms by which perturbations in epithelial-mesenchymal interactions

  8. Reciprocal Inflammatory Signaling Between Intestinal Epithelial Cells and Adipocytes in the Absence of Immune Cells

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    Yu Takahashi

    2017-09-01

    Full Text Available Visceral fat accumulation as observed in Crohn's disease and obesity is linked to chronic gut inflammation, suggesting that accumulation of gut adipocytes can trigger local inflammatory signaling. However, direct interactions between intestinal epithelial cells (IECs and adipocytes have not been investigated, in part because IEC physiology is difficult to replicate in culture. In this study, we originally prepared intact, polarized, and cytokine responsive IEC monolayers from primary or induced pluripotent stem cell-derived intestinal organoids by simple and repeatable methods. When these physiological IECs were co-cultured with differentiated adipocytes in Transwell, pro-inflammatory genes were induced in both cell types, suggesting reciprocal inflammatory activation in the absence of immunocompetent cells. These inflammatory responses were blocked by nuclear factor-κB or signal transducer and activator of transcription 3 inhibition and by anti-tumor necrosis factor- or anti-interleukin-6-neutralizing antibodies. Our results highlight the utility of these monolayers for investigating IEC biology. Furthermore, this system recapitulates the intestinal epithelium–mesenteric fat signals that potentially trigger or worsen inflammatory disorders such as Crohn's disease and obesity-related enterocolitis.

  9. Lipopolysaccharide-binding protein: localization in secretory granules of Paneth cells in the mouse small intestine

    DEFF Research Database (Denmark)

    Hansen, Gert H; Rasmussen, Karina; Niels-Christiansen, Lise-Lotte

    2009-01-01

    Lipopolysaccharide (LPS)-binding protein (LBP) is an acute-phase protein involved in the host's response to endotoxin and mainly synthesized and secreted to the blood by the liver. But in addition, LBP is also made by extrahepatic cells, including the enterocyte-like cell line Caco-2. To study...... in closer detail the synthesis and storage of LBP in the intestinal mucosal epithelium, we performed an immunolocalization of LBP in mouse small intestine. By immunofluorescence microscopy, an antibody recognizing the 58-60 kDa protein of LBP distinctly labeled a small population of cells located deep...... into the crypts. This cell population was also positive for lysozyme and alpha-defensin 4, identifying Paneth cells as the main intestinal LBP-producing cells. By immunogold electron microscopy, intense labeling was observed in the secretory granules of these cells. We conclude that Paneth cells express LBP...

  10. PAF-Myc-Controlled Cell Stemness Is Required for Intestinal Regeneration and Tumorigenesis.

    Science.gov (United States)

    Kim, Moon Jong; Xia, Bo; Suh, Han Na; Lee, Sung Ho; Jun, Sohee; Lien, Esther M; Zhang, Jie; Chen, Kaifu; Park, Jae-Il

    2018-03-12

    The underlying mechanisms of how self-renewing cells are controlled in regenerating tissues and cancer remain ambiguous. PCNA-associated factor (PAF) modulates DNA repair via PCNA. Also, PAF hyperactivates Wnt/β-catenin signaling independently of PCNA interaction. We found that PAF is expressed in intestinal stem and progenitor cells (ISCs and IPCs) and markedly upregulated during intestinal regeneration and tumorigenesis. Whereas PAF is dispensable for intestinal homeostasis, upon radiation injury, genetic ablation of PAF impairs intestinal regeneration along with the severe loss of ISCs and Myc expression. Mechanistically, PAF conditionally occupies and transactivates the c-Myc promoter, which induces the expansion of ISCs/IPCs during intestinal regeneration. In mouse models, PAF knockout inhibits Apc inactivation-driven intestinal tumorigenesis with reduced tumor cell stemness and suppressed Wnt/β-catenin signaling activity, supported by transcriptome profiling. Collectively, our results unveil that the PAF-Myc signaling axis is indispensable for intestinal regeneration and tumorigenesis by positively regulating self-renewing cells. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Coumestrol Epigenetically Suppresses Cancer Cell Proliferation: Coumestrol Is a Natural Haspin Kinase Inhibitor

    Directory of Open Access Journals (Sweden)

    Jong-Eun Kim

    2017-10-01

    Full Text Available Targeting epigenetic changes in gene expression in cancer cells may offer new strategies for the development of selective cancer therapies. In the present study, we investigated coumestrol, a natural compound exhibiting broad anti-cancer effects against skin melanoma, lung cancer and colon cancer cell growth. Haspin kinase was identified as a direct target protein of coumestrol using kinase profiling analysis. Histone H3 is a direct substrate of haspin kinase. We observed haspin kinase overexpression as well as greater phosphorylation of histone H3 at threonine 3 (Thr-3 in the cancer cells compared to normal cells. Computer modeling using the Schrödinger Suite program identified the binding interface within the ATP binding site. These findings suggest that the anti-cancer effect of coumestrol is due to the direct targeting of haspin kinase. Coumestrol has considerable potential for further development as a novel anti-cancer agent.

  12. Lgr5 intestinal stem cells have high telomerase activity and randomly segregate their chromosomes

    NARCIS (Netherlands)

    Schepers, A.G.; Vries, R.G.J.; van den Born, M.M.W.; van de Wetering, M.L.; Clevers, H.

    2011-01-01

    Somatic cells have been proposed to be limited in the number of cell divisions they can undergo. This is thought to be a mechanism by which stem cells retain their integrity preventing disease. However, we have recently discovered intestinal crypt stem cells that persist for the lifetime of a mouse,

  13. Phosphoinositide 3–kinase γ participates in T cell receptor–induced T cell activation

    Science.gov (United States)

    Alcázar, Isabela; Marqués, Miriam; Kumar, Amit; Hirsch, Emilio; Wymann, Matthias; Carrera, Ana C.; Barber, Domingo F.

    2007-01-01

    Class I phosphoinositide 3–kinases (PI3Ks) constitute a family of enzymes that generates 3-phosphorylated polyphosphoinositides at the cell membrane after stimulation of protein tyrosine (Tyr) kinase–associated receptors or G protein–coupled receptors (GPCRs). The class I PI3Ks are divided into two types: class IA p85/p110 heterodimers, which are activated by Tyr kinases, and the class IB p110γ isoform, which is activated by GPCR. Although the T cell receptor (TCR) is a protein Tyr kinase–associated receptor, p110γ deletion affects TCR-induced T cell stimulation. We examined whether the TCR activates p110γ, as well as the consequences of interfering with p110γ expression or function for T cell activation. We found that after TCR ligation, p110γ interacts with Gαq/11, lymphocyte-specific Tyr kinase, and ζ-associated protein. TCR stimulation activates p110γ, which affects 3-phosphorylated polyphosphoinositide levels at the immunological synapse. We show that TCR-stimulated p110γ controls RAS-related C3 botulinum substrate 1 activity, F-actin polarization, and the interaction between T cells and antigen-presenting cells, illustrating a crucial role for p110γ in TCR-induced T cell activation. PMID:17998387

  14. Mechanisms of Cell Polarity-Controlled Epithelial Homeostasis and Immunity in the Intestine.

    Science.gov (United States)

    Klunder, Leon J; Faber, Klaas Nico; Dijkstra, Gerard; van IJzendoorn, Sven C D

    2017-07-05

    Intestinal epithelial cell polarity is instrumental to maintain epithelial homeostasis and balance communications between the gut lumen and bodily tissue, thereby controlling the defense against gastrointestinal pathogens and maintenance of immune tolerance to commensal bacteria. In this review, we highlight recent advances with regard to the molecular mechanisms of cell polarity-controlled epithelial homeostasis and immunity in the human intestine. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

  15. Radioprotective effect of dextran sulphate and aerogenic hypoxia on intestinal crypt stem cells in mice

    International Nuclear Information System (INIS)

    Vacek, A.; Bartonickova, A.; Rotkovska, D.; Konoplyanikova, O.A.; Konoplyanikov, A.G.

    1991-01-01

    A single intraperitoneal injection of dextran sulfate given 6 h before irradiation produced higher numbers of microcolonies of intestinal crypt stem cells in whole-body irradiated mice than an injection of saline in control mice. If dextran sulfate and hypoxia are combined, the radioprotective effect of hypoxia on intestinal crypt stem cells depends on the time interval between irradiation and administration of dextran sulfate. (author). 2 figs., 12 refs

  16. Gut microbiota regulates NKG2D ligand expression on intestinal epithelial cells

    DEFF Research Database (Denmark)

    Hansen, Camilla Hartmann Friis; Holm, Thomas L.; Krych, Lukasz

    2013-01-01

    Intestinal epithelial cells (IECs) are one of a few cell types in the body with constitutive surface expression of natural killer group 2 member D (NKG2D) ligands, although the magnitude of ligand expression by IECs varies. Here, we investigated whether the gut microbiota regulates the NKG2D ligand...... expression is kept in check by an intestinal regulatory immune milieu induced by members of the gut microbiota, for example A. muciniphila....

  17. Csk Homologous Kinase, a Potential Regulator of CXCR4-mediated Breast Cancer Cell Metastasis

    Science.gov (United States)

    2010-08-31

    SH2 ) and SH3 domains and lacks the consensus tyrosine phosphorylation and myristylation sites found in Src family kinases . CHK has been shown to...0350 TITLE: Csk Homologous Kinase , a Potential Regulator of CXCR4-mediated Breast Cancer Cell Metastasis PRINCIPAL INVESTIGATOR: Byeong-Chel...1 AUG 2009 - 31 JUL 2010 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER W81XWH-09-1-0350 Csk Homologous Kinase , a Potential Regulator

  18. Regulation of T-cell Responses in the Inflamed Intestine

    NARCIS (Netherlands)

    M.A. Van Leeuwen (Marieke)

    2015-01-01

    markdownabstract__Abstract__ The intestinal immune system protects the mucosal surfaces from pathogenic microorganisms. On the other hand it maintains tolerance towards dietary antigens and non-pathogenic microorganisms. The immune system continuously tailors these inflammatory and tolerogenic

  19. Stem cell factor induces phosphatidylinositol 3'-kinase-dependent Lyn/Tec/Dok-1 complex formation in hematopoietic cells

    NARCIS (Netherlands)

    van Dijk, T. B.; van den Akker, E.; Amelsvoort, M. P.; Mano, H.; Löwenberg, B.; von Lindern, M.

    2000-01-01

    Stem cell factor (SCF) has an important role in the proliferation, differentiation, survival, and migration of hematopoietic cells. SCF exerts its effects by binding to cKit, a receptor with intrinsic tyrosine kinase activity. Activation of phosphatidylinositol 3'-kinase (PI3-K) by cKit was

  20. c-Kit mutation reduce intestinal epithelial cell proliferation and migration, but not influence intestinal permeability stimulated by lipopolysaccharide.

    Science.gov (United States)

    Xue, Hong; Wang, Feng Yun; Kang, Qian; Tang, Xu Dong

    2018-06-20

    The proto-oncogene c-kit, as a marker of interstitial cells of Cajal (ICCs) in the gastrointestinal tract, plays an important role in the ICCs. Although limited evidences showed c-kit is present in the colonic epithelium but its roles remain unclear. In the present study, we aimed to investigate the expression, location and function of c-kit in the intestinal epithelium. Immunofluorescence, western blotting, and RT-PCR were performed to detect the expression and location of c-kit in the intestinal mucosa of WT mice. We investigated intestinal epithelial proliferation and migration in vivo by performing 5-Bromodeoxyuridine (BrdU) incorporation and Ki-67 staining in WT and Wads m/m mice. An Ussing chamber with fluorescein-isothiocyanate dextran 4000 was used to detect the transepithelial electric resistance (TER), short circuit current (ISC) and permeability across ex vivo colon segments under control and endotoxaemia conditions. We demonstrated that c-kit was located and expressed in the gut crypt compartment in WT mice, which was demonstrated in the c-kit mutant mice (Wads m/m ). In addition, both the number of proliferating cells and the percentage of the distance migrated were lower in the Wads m/m mice than those in the WT mice. Moreover, the intestinal permeability, TER and tight junction were unaltered in the Wads m/m mice under endotoxic conditions compared with those in both the control condition and the WT mice. Altogether, these observations imply that the expression of c-kit in the colonic epithelium is involved in the proliferation and permeability of the colonic epithelium. Copyright © 2018. Published by Elsevier GmbH.

  1. The role of CD103+ Dendritic cells in the intestinal mucosal immune system.

    Directory of Open Access Journals (Sweden)

    Darren Thomas Ruane

    2011-07-01

    Full Text Available While dendritic cells (DC are central to the induction and regulation of adaptive immunity, these cells are very heterogenous and specific subsets can be characterized based on the expression of cell surface markers and functional properties. Intestinal CD103+ DCs are the subject of particular interest due to their role in regulating mucosal immunity. Since the epithelial surfaces are constantly exposed to a high antigenic load, tight regulation of innate and adaptive intestinal immune responses is vital as intestinal inflammation can have detrimental consequences for the host. Strategically positioned within the lamina propria, CD103+ DCs play an important role in maintaining intestinal immune homeostasis. These cells are required for the induction of tolerogenic immune responses and imprinting gut homing phenotypic changes on antigen-specific T cells. Recent insights into their development and regulatory properties have revealed additional immunoregulatory roles and further highlighted their importance for intestinal immunity. In this review we discuss the nature of the intestinal CD103+ DC population and the emerging roles of these cells in the regulation of mucosal immunity.

  2. Effects of fasting and refeeding on intestinal cell proliferation and apoptosis in hammerhead shark (Sphyrna lewini

    Directory of Open Access Journals (Sweden)

    Hideya Takahashi

    2014-04-01

    Full Text Available Objective: To examine the effects of fasting and refeeding on intestinal cell proliferation and apoptosis in an opportunistic predator, hammerhead shark (Sphyrna lewini of elasmobranch fishes which are among the earliest known extant groups of vertebrates to have the valvular intestine typical for the primitive species. Methods: Animals were euthanized after 5-10 d of fasting or feeding, or after 10-day fasting and 5-day refeeding. Intestinal apoptosis and cell proliferation were assessed by using oligonucleotide detection assay, terminal deoxynucleotidyl transferase dUTP nick end labeling staining, and immunohistochemistry of proliferating cells nuclear antigen. Results: Plasma levels of cholesterol and glucose were reduced by fasting. Intestinal apoptosis generally decreased during fasting. Numerous apoptotic cells were observed around the tips of the villi, primarily in the epithelium in the fed sharks, whereas fewer labeled nuclei were detected in the epithelium of fasted sharks. Refeeding returned intestinal apoptosis to the level in the fed sharks. Proliferating cells were observed in the epithelium around the troughs of the villi and greater in number in fed sharks, whereas fewer labeled nuclei were detected in fasted sharks. Conclusions: The cell turnover is modified in both intestinal epithelia of the shark and the murines by fasting/feeding, but in opposite directions. The difference may reflect the feeding ecology of the elasmobranchs, primitive intermittent feeders.

  3. Characterization of goat inner cell mass derived cells in double kinase inhibition condition

    International Nuclear Information System (INIS)

    Wei, Qiang; Xi, Qihui; Liu, Xiaokun; Meng, Kai; Zhao, Xiaoe; Ma, Baohua

    2017-01-01

    The identification of small molecular inhibitors, which were reported to promote the derivation of mouse and human embryonic stem cells (ESCs), provides a potential strategy for the derivation of domesticated ungulate ESCs. In present study, goat inner cell mass (ICM) derived cells in the double inhibition (2i) condition, in which, mitogen-activated protein kinase kinase (MAP2K) and glycogen synthase kinase 3 (GSK3) were inhibited by PD0325901 and BIO respectively, were characterized. The results showed that goat ICM derived cells in 2i medium adding leukaemia inhibitor factor (LIF) possessed a mouse ES-like morphology. But these cells had much compromised proliferation capacity, resulting in difficulty in expansion. In 2i alone medium, goat ICM derived cells possessed primate ES-like morphology. These cells expressed pluripotent markers and could differentiate into derivatives of three germ layers in vitro. However, these cells could not be proliferated in long-term (persisted for 15 passages) because of spontaneously neural differentiation. Additionally, goat ICM derived cells could be inducing differentiated into neural lineage in vitro. Although goat ESCs could not be established in PD0325901 and BIO alone medium, this derivation condition provides a useful research system to find signaling molecular those regulate early embryonic development and pluripotency in goat. - Highlights: • Goat inner cell mass derived cells possessed finite pluripotency in 2i condition. • These cells could not be proliferated in long-term in 2i condition. • These cells could spontaneously and inductively differentiate into neural lineage.

  4. Epithelial Cell Damage Activates Bactericidal/Permeability Increasing-Protein (BPI Expression in Intestinal Epithelium

    Directory of Open Access Journals (Sweden)

    Arjun Balakrishnan

    2017-08-01

    Full Text Available As the first line of defense against invading pathogen, intestinal epithelium produces various antimicrobial proteins (AMP that help in clearance of pathogen. Bactericidal/permeability-increasing protein (BPI is a 55 kDa AMP that is expressed in intestinal epithelium. Dysregulation of BPI in intestinal epithelium is associated with various inflammatory diseases like Crohn’s Disease, Ulcerative colitis, and Infectious enteritis’s. In this paper, we report a direct correlation between intestinal damage and BPI expression. In Caco-2 cells, we see a significant increase in BPI levels upon membrane damage mediated by S. aureus infection and pore-forming toxins (Streptolysin and Listeriolysin. Cells detect changes in potassium level as a Danger-associated molecular pattern associated with cell damage and induce BPI expression in a p38 dependent manner. These results are further supported by in vivo findings that the BPI expression in murine intestinal epithelium is induced upon infection with bacteria which cause intestinal damage (Salmonella Typhimurium and Shigella flexneri whereas mutants that do not cause intestinal damage (STM ΔfliC and STM ΔinvC did not induce BPI expression. Our results suggest that epithelial damage associated with infection act as a signal to induce BPI expression.

  5. Crohn's disease intestinal CD4+ T cells have impaired interleukin-10 productionwhich is not restored by probiotic bacteria

    DEFF Research Database (Denmark)

    Hvas, Christian L; Kelsen, Jens; Agnholt, Jørgen

    2007-01-01

    OBJECTIVE: Crohn's disease (CD) has been associated with low mucosal interleukin (IL)-10 production, but the mechanism behind this deficiency remains unclear. The aim of this study was to investigate IL-10 and interferon (IFN)-gamma production in intestinal CD4+ T cells from CD patients and healthy...... volunteers (HV) and to examine how this was affected by bacterial products and the presence or absence of autologous dendritic cells. MATERIAL AND METHODS: We cultured intestinal CD4+ T cells from CD patients (n=9) and HV (n=6) and differentiated dendritic cells from their peripheral monocytes. Intestinal T...... this imbalance in CD, but tended to do so in HV. When there were no dendritic cells, CD intestinal T cells responded to autologous bacteria with an increased IFN-gamma production (2.3+/-1.3 ng/ml) compared with HV intestinal T cells (0.3+/-0.2 ng/ml). CONCLUSIONS: Crohn's disease intestinal CD4+ T cells display...

  6. Regulation of the vertebrate cell cycle by the cdc2 protein kinase

    International Nuclear Information System (INIS)

    Draetta, G.; Brizuela, L.; Moran, B.; Beach, D.

    1988-01-01

    A homolog of the cdc2/CDC28 protein kinase of yeast is found in all vertebrate species that have been investigated. Human cdc2 exists as a complex with a 13-kD protein that is homologous to the suc1 gene product of fission yeast. In both human and fission yeast cells, the protein kinase also exists in a complex with a 62-kD polypeptide that has not been identified genetically but acts as a substrate in vitro. The authors have studied the properties of the protein kinase in rat and human cells, as well as in Xenopus eggs. They find that in baby rat kidney (BRK) cells, which are quiescent in cell culture, the cdc2 protein is not synthesized. However, synthesis is rapidly induced in response to proliferative activation by infection with adenovirus. In human HeLa cells, the protein kinase is present continuously. It behaves as a cell-cycle oscillator that is inactive in G 1 but displays maximal enzymatic activity during mitotic metaphase. These observations indicate that in a wide variety of vertebrate cells, the cdc2 protein kinase is involved in regulating mitosis. The authors' approach taken toward study of the cdc2 protein kinase highlights the possibilities that now exist for combining the advantages of ascomycete genetics with the cell-free systems of Xenopus and the biochemical advantages of tissue culture cells to investigate fundamental problems of the cell cycle

  7. Enteroendocrine cells are specifically marked by cell surface expression of claudin-4 in mouse small intestine.

    Directory of Open Access Journals (Sweden)

    Takahiro Nagatake

    Full Text Available Enteroendocrine cells are solitary epithelial cells scattered throughout the gastrointestinal tract and produce various types of hormones, constituting one of the largest endocrine systems in the body. The study of these rare epithelial cells has been hampered by the difficulty in isolating them because of the lack of specific cell surface markers. Here, we report that enteroendocrine cells selectively express a tight junction membrane protein, claudin-4 (Cld4, and are efficiently isolated with the use of an antibody specific for the Cld4 extracellular domain and flow cytometry. Sorted Cld4+ epithelial cells in the small intestine exclusively expressed a chromogranin A gene (Chga and other enteroendocrine cell-related genes (Ffar1, Ffar4, Gpr119, and the population was divided into two subpopulations based on the activity of binding to Ulex europaeus agglutinin-1 (UEA-1. A Cld4+UEA-1- cell population almost exclusively expressed glucose-dependent insulinotropic polypeptide gene (Gip, thus representing K cells, whereas a Cld4+UEA-1+ cell population expressed other gut hormone genes, including glucagon-like peptide 1 (Gcg, pancreatic polypeptide-like peptide with N-terminal tyrosine amide (Pyy, cholecystokinin (Cck, secretin (Sct, and tryptophan hydroxylase 1 (Tph1. In addition, we found that orally administered luminal antigens were taken up by the solitary Cld4+ cells in the small intestinal villi, raising the possibility that enteroendocrine cells might also play a role in initiation of mucosal immunity. Our results provide a useful tool for the cellular and functional characterization of enteroendocrine cells.

  8. Intestinal epithelial cell-specific RARα depletion results in aberrant epithelial cell homeostasis and underdeveloped immune system.

    Science.gov (United States)

    Jijon, H B; Suarez-Lopez, L; Diaz, O E; Das, S; De Calisto, J; Yaffe, M B; Pittet, M J; Mora, J R; Belkaid, Y; Xavier, R J; Villablanca, E J

    2018-05-01

    Retinoic acid (RA), a dietary vitamin A metabolite, is crucial in maintaining intestinal homeostasis. RA acts on intestinal leukocytes to modulate their lineage commitment and function. Although the role of RA has been characterized in immune cells, whether intestinal epithelial cells (IECs) rely on RA signaling to exert their immune-regulatory function has not been examined. Here we demonstrate that lack of RA receptor α (RARα) signaling in IECs results in deregulated epithelial lineage specification, leading to increased numbers of goblet cells and Paneth cells. Mechanistically, lack of RARα resulted in increased KLF4 + goblet cell precursors in the distal bowel, whereas RA treatment inhibited klf4 expression and goblet cell differentiation in zebrafish. These changes in secretory cells are associated with increased Reg3g, reduced luminal bacterial detection, and an underdeveloped intestinal immune system, as evidenced by an almost complete absence of lymphoid follicles and gut resident mononuclear phagocytes. This underdeveloped intestinal immune system shows a decreased ability to clear infection with Citrobacter rodentium. Collectively, our findings indicate that epithelial cell-intrinsic RARα signaling is critical to the global development of the intestinal immune system.

  9. Stem cell factor induces phosphatidylinositol 3'-kinase-dependent Lyn/Tec/Dok-1 complex formation in hematopoietic cells

    NARCIS (Netherlands)

    T.B. van Dijk (Thamar); M. Parren-Van Amelsvoort (Martine); H. Mano; M.M. von Lindern (Marieke); B. Löwenberg (Bob); E. van den Akker (Emile)

    2000-01-01

    textabstractStem cell factor (SCF) has an important role in the proliferation, differentiation, survival, and migration of hematopoietic cells. SCF exerts its effects by binding to cKit, a receptor with intrinsic tyrosine kinase activity. Activation of

  10. The role of p38 MAP kinase and c-Jun N-terminal protein kinase signaling in the differentiation and apoptosis of immortalized neural stem cells

    International Nuclear Information System (INIS)

    Yang, Se-Ran; Cho, Sung-Dae; Ahn, Nam-Shik; Jung, Ji-Won; Park, Joon-Suk; Jo, Eun-Hye; Hwang, Jae-Woong; Kim, Sung-Hoon; Lee, Bong-Hee; Kang, Kyung-Sun; Lee, Yong-Soon

    2005-01-01

    The two distinct members of the mitogen-activated protein (MAP) kinase family c-Jun N-terminal protein kinase (JNK) and p38 MAP kinase, play an important role in central nervous system (CNS) development and differentiation. However, their role and functions are not completely understood in CNS. To facilitate in vitro study, we have established an immortal stem cell line using SV40 from fetal rat embryonic day 17. In these cells, MAP kinase inhibitors (SP600125, SB202190, and PD98059) were treated for 1, 24, 48, and 72 h to examine the roles of protein kinases. Early inhibition of JNK did not alter phenotypic or morphological changes of immortalized cells, however overexpression of Bax and decrease of phosphorylated AKT was observed. The prolonged inhibition of JNK induced polyploidization of immortalized cells, and resulted in differentiation and inhibition of cell proliferation. Moreover, JNK and p38 MAP kinase but not ERK1/2 was activated, and p21, p53, and Bax were overexpressed by prolonged inhibition of JNK. These results indicate that JNK and p38 MAP kinase could play dual roles on cell survival and apoptosis. Furthermore, this established cell line could facilitate study of the role of JNK and p38 MAP kinase on CNS development or differentiation/apoptosis

  11. Involvement of JAK2 upstream of the PI 3-kinase in cell-cell adhesion regulation by gastrin

    International Nuclear Information System (INIS)

    Ferrand, Audrey; Kowalski-Chauvel, Aline; Bertrand, Claudine; Pradayrol, Lucien; Fourmy, Daniel; Dufresne, Marlene; Seva, Catherine

    2004-01-01

    The Janus kinase/signal transducers and activators of transcription (JAK/STAT) signaling pathway has been implicated in cell transformation and proliferation. Besides aberrant cell proliferation, loss of cell-cell adhesion during epithelial-mesenchymal transition (EMT) is an important event which occurs during development of epithelial cancers. However, the role of JAK-dependent pathways in this process is not known. We analyzed the involvement of these pathways in the regulation of E-cadherin-dependent cell-cell adhesion by gastrin, a mitogenic factor for gastrointestinal (GI) tract. We identified JAK2/STAT3 as a new pathway in gastrin signaling. We demonstrated that JAK2 functions as an upstream mediator of the phosphatidylinositol 3 (PI 3)-kinase activity in gastrin signaling. Indeed, we observed a coprecipitation of both kinases and an inhibition of gastrin-induced PI 3-kinase activation when JAK2 activity is blocked. We also demonstrated that loss of cell-cell adhesion and the increase in cell motility induced by gastrin required the activation of JAK2 and the PI 3-kinase. Indeed, the modifications in localization of adherens junctions proteins and the migration, observed in gastrin-stimulated cells, were reversed by inhibition of both kinases. These results described the involvement of JAK2 in the modulation of cell-cell adhesion in epithelial cells. They support a possible role of JAK2 in the epithelial-mesenchymal transition which occurs during malignant development

  12. Intestinal Epithelial Cells Modulate Antigen-Presenting Cell Responses to Bacterial DNA

    Science.gov (United States)

    Campeau, J. L.; Salim, S. Y.; Albert, E. J.; Hotte, N.

    2012-01-01

    Intestinal epithelial cells and antigen-presenting cells orchestrate mucosal innate immunity. This study investigated the role of bacterial DNA in modulating epithelial and bone marrow-derived antigen-presenting cells (BM-APCs) and subsequent T-lymphocyte responses. Murine MODE-K epithelial cells and BM-APCs were treated with DNA from either Bifidobacterium breve or Salmonella enterica serovar Dublin directly and under coculture conditions with CD4+ T cells. Apical stimulation of MODE-K cells with S. Dublin DNA enhanced secretion of cytokines from underlying BM-APCs and induced interleukin-17 (IL-17) and gamma interferon (IFN-γ) secretion from CD4+ T cells. Bacterial DNA isolated from either strain induced maturation and increased cytokine secretion from BM-APCs. Conditioned medium from S. Dublin-treated MODE-K cells elicited an increase in cytokine secretion similar to that seen for S. Dublin DNA. Treatment of conditioned medium from MODE-K cells with RNase and protease prevented the S. Dublin-induced increased cytokine secretion. Oral feeding of mice with B. breve DNA resulted in enhanced levels of colonic IL-10 and transforming growth factor β (TGFβ) compared with what was seen for mice treated with S. Dublin DNA. In contrast, feeding mice with S. Dublin DNA increased levels of colonic IL-17 and IL-12p70. T cells from S. Dublin DNA-treated mice secreted high levels of IL-12 and IFN-γ compared to controls and B. breve DNA-treated mice. These results demonstrate that intestinal epithelial cells are able to modulate subsequent antigen-presenting and T-cell responses to bacterial DNA with pathogenic but not commensal bacterial DNA inducing effector CD4+ T lymphocytes. PMID:22615241

  13. Bmi1 regulates murine intestinal stem cell proliferation and self-renewal downstream of Notch

    DEFF Research Database (Denmark)

    López-Arribillaga, Erika; Rodilla, Verónica; Pellegrinet, Luca

    2015-01-01

    Genetic data indicate that abrogation of Notch-Rbpj or Wnt-β-catenin pathways results in the loss of the intestinal stem cells (ISCs). However, whether the effect of Notch is direct or due to the aberrant differentiation of the transit-amplifying cells into post-mitotic goblet cells is unknown. T...

  14. TGFβR signalling controls CD103+CD11b+ dendritic cell development in the intestine

    NARCIS (Netherlands)

    L.J. Bain (Lisa); Montgomery, J. (J.); C.L. Scott (C.); J.M. Kel (Junda); M.J.H. Girard-Madoux (Mathilde); L. Martens (Liesbet); Zangerle-Murray, T.F.P. (T. F.P.); J.L. Ober-Blöbaum (Julia); D.J. Lindenbergh-Kortleve (Dicky); J.N. Samsom (Janneke); S. Henri (Sandrine); T. Lawrence (Toby); Y. Saeys (Yvan); B. Malissen (Bernard); M. Dalod (Marc); B.E. Clausen (Bjorn); Mowat, A.M. (A. McI.)

    2017-01-01

    textabstractCD103+CD11b+ dendritic cells (DCs) are unique to the intestine, but the factors governing their differentiation are unclear. Here we show that transforming growth factor receptor 1 (TGFβR1) has an indispensable, cell intrinsic role in the development of these cells. Deletion of Tgfbr1

  15. Activation of MEK1 or MEK2 isoform is sufficient to fully transform intestinal epithelial cells and induce the formation of metastatic tumors

    International Nuclear Information System (INIS)

    Voisin, Laure; Basik, Mark; Meloche, Sylvain; Julien, Catherine; Duhamel, Stéphanie; Gopalbhai, Kailesh; Claveau, Isabelle; Saba-El-Leil, Marc K; Rodrigue-Gervais, Ian Gaël; Gaboury, Louis; Lamarre, Daniel

    2008-01-01

    The Ras-dependent ERK1/2 MAP kinase signaling pathway plays a central role in cell proliferation control and is frequently activated in human colorectal cancer. Small-molecule inhibitors of MEK1/MEK2 are therefore viewed as attractive drug candidates for the targeted therapy of this malignancy. However, the exact contribution of MEK1 and MEK2 to the pathogenesis of colorectal cancer remains to be established. Wild type and constitutively active forms of MEK1 and MEK2 were ectopically expressed by retroviral gene transfer in the normal intestinal epithelial cell line IEC-6. We studied the impact of MEK1 and MEK2 activation on cellular morphology, cell proliferation, survival, migration, invasiveness, and tumorigenesis in mice. RNA interference was used to test the requirement for MEK1 and MEK2 function in maintaining the proliferation of human colorectal cancer cells. We found that expression of activated MEK1 or MEK2 is sufficient to morphologically transform intestinal epithelial cells, dysregulate cell proliferation and induce the formation of high-grade adenocarcinomas after orthotopic transplantation in mice. A large proportion of these intestinal tumors metastasize to the liver and lung. Mechanistically, activation of MEK1 or MEK2 up-regulates the expression of matrix metalloproteinases, promotes invasiveness and protects cells from undergoing anoikis. Importantly, we show that silencing of MEK2 expression completely suppresses the proliferation of human colon carcinoma cell lines, whereas inactivation of MEK1 has a much weaker effect. MEK1 and MEK2 isoforms have similar transforming properties and are able to induce the formation of metastatic intestinal tumors in mice. Our results suggest that MEK2 plays a more important role than MEK1 in sustaining the proliferation of human colorectal cancer cells

  16. Effects of propofol on damage of rat intestinal epithelial cells induced by heat stress and lipopolysaccharides

    Energy Technology Data Exchange (ETDEWEB)

    Tang, J.; Jiang, Y. [Southern Medical University, Nanfang Hospital, Department of Anesthesia, Guangzhou, China, Department of Anesthesia, Nanfang Hospital, Southern Medical University, Guangzhou (China); Tang, Y.; Chen, B. [Guangzhou General Hospital of Guangzhou Military Command, Department of Intensive Care Unit, Guangzhou, China, Department of Intensive Care Unit, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou (China); Sun, X. [Laboratory of Traditional Chinese Medicine Syndrome, School of Traditional Chinese Medicine, Southern Medical University, Guangzhou (China); Su, L.; Liu, Z. [Guangzhou General Hospital of Guangzhou Military Command, Department of Intensive Care Unit, Guangzhou, China, Department of Intensive Care Unit, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou (China)

    2013-06-25

    Gut-derived endotoxin and pathogenic bacteria have been proposed as important causative factors of morbidity and death during heat stroke. However, it is still unclear what kind of damage is induced by heat stress. In this study, the rat intestinal epithelial cell line (IEC-6) was treated with heat stress or a combination of heat stress and lipopolysaccharide (LPS). In addition, propofol, which plays an important role in anti-inflammation and organ protection, was applied to study its effects on cellular viability and apoptosis. Heat stress, LPS, or heat stress combined with LPS stimulation can all cause intestinal epithelial cell damage, including early apoptosis and subsequent necrosis. However, propofol can alleviate injuries caused by heat stress, LPS, or the combination of heat stress and LPS. Interestingly, propofol can only mitigate LPS-induced intestinal epithelial cell apoptosis, and has no protective role in heat-stress-induced apoptosis. This study developed a model that can mimic the intestinal heat stress environment. It demonstrates the effects on intestinal epithelial cell damage, and indicated that propofol could be used as a therapeutic drug for the treatment of heat-stress-induced intestinal injuries.

  17. Effects of propofol on damage of rat intestinal epithelial cells induced by heat stress and lipopolysaccharides

    International Nuclear Information System (INIS)

    Tang, J.; Jiang, Y.; Tang, Y.; Chen, B.; Sun, X.; Su, L.; Liu, Z.

    2013-01-01

    Gut-derived endotoxin and pathogenic bacteria have been proposed as important causative factors of morbidity and death during heat stroke. However, it is still unclear what kind of damage is induced by heat stress. In this study, the rat intestinal epithelial cell line (IEC-6) was treated with heat stress or a combination of heat stress and lipopolysaccharide (LPS). In addition, propofol, which plays an important role in anti-inflammation and organ protection, was applied to study its effects on cellular viability and apoptosis. Heat stress, LPS, or heat stress combined with LPS stimulation can all cause intestinal epithelial cell damage, including early apoptosis and subsequent necrosis. However, propofol can alleviate injuries caused by heat stress, LPS, or the combination of heat stress and LPS. Interestingly, propofol can only mitigate LPS-induced intestinal epithelial cell apoptosis, and has no protective role in heat-stress-induced apoptosis. This study developed a model that can mimic the intestinal heat stress environment. It demonstrates the effects on intestinal epithelial cell damage, and indicated that propofol could be used as a therapeutic drug for the treatment of heat-stress-induced intestinal injuries

  18. Distinctive genomic signature of neural and intestinal organoids from familial Parkinson's disease patient-derived induced pluripotent stem cells.

    Science.gov (United States)

    Son, M-Y; Sim, H; Son, Y S; Jung, K B; Lee, M-O; Oh, J-H; Chung, S-K; Jung, C-R; Kim, J

    2017-12-01

    The leucine-rich repeat kinase 2 (LRRK2) G2019S mutation is the most common genetic cause of Parkinson's disease (PD). There is compelling evidence that PD is not only a brain disease but also a gastrointestinal disorder; nonetheless, its pathogenesis remains unclear. We aimed to develop human neural and intestinal tissue models of PD patients harbouring an LRRK2 mutation to understand the link between LRRK2 and PD pathology by investigating the gene expression signature. We generated PD patient-specific induced pluripotent stem cells (iPSCs) carrying an LRRK2 G2019S mutation (LK2GS) and then differentiated into three-dimensional (3D) human neuroectodermal spheres (hNESs) and human intestinal organoids (hIOs). To unravel the gene and signalling networks associated with LK2GS, we analysed differentially expressed genes in the microarray data by functional clustering, gene ontology (GO) and pathway analyses. The expression profiles of LK2GS were distinct from those of wild-type controls in hNESs and hIOs. The most represented GO biological process in hNESs and hIOs was synaptic transmission, specifically synaptic vesicle trafficking, some defects of which are known to be related to PD. The results were further validated in four independent PD-specific hNESs and hIOs by microarray and qRT-PCR analysis. We provide the first evidence that LK2GS also causes significant changes in gene expression in the intestinal cells. These hNES and hIO models from the same genetic background of PD patients could be invaluable resources for understanding PD pathophysiology and for advancing the complexity of in vitro models with 3D expandable organoids. © 2017 British Neuropathological Society.

  19. Fermented soya bean (tempe) extracts reduce adhesion of enterotoxigenic Escherichia coli to intestinal epithelial cells.

    Science.gov (United States)

    Roubos-van den Hil, P J; Nout, M J R; Beumer, R R; van der Meulen, J; Zwietering, M H

    2009-03-01

    This study aimed to investigate the effect of processed soya bean, during the successive stages of tempe fermentation and different fermentation times, on adhesion of enterotoxigenic Escherichia coli (ETEC) K88 to intestinal brush border cells as well as Caco-2 intestinal epithelial cells; and to clarify the mechanism of action. Tempe was prepared at controlled laboratory scale using Rhizopus microsporus var. microsporus as the inoculum. Extracts of raw, soaked and cooked soya beans reduced ETEC adhesion to brush border cells by 40%. Tempe extracts reduced adhesion by 80% or more. ETEC adhesion to Caco-2 cells reduced by 50% in the presence of tempe extracts. ETEC K88 bacteria were found to interact with soya bean extracts, and this may contribute to the observed decrease of ETEC adhesion to intestinal epithelial cells. Fermented soya beans (tempe) reduce the adhesion of ETEC to intestinal epithelial cells of pig and human origin. This reduced adhesion is caused by an interaction between ETEC K88 bacteria and soya bean compounds. The results strengthen previous observations on the anti-diarrhoeal effect of tempe. This effect indicates that soya-derived compounds may reduce adhesion of ETEC to intestinal cells in pigs as well as in humans and prevent against diarrhoeal diseases.

  20. Establishment of primary bovine intestinal epithelial cell culture and clone method.

    Science.gov (United States)

    Zhan, Kang; Lin, Miao; Liu, Ming-Mei; Sui, Yang-Nan; Zhao, Guo-Qi

    2017-01-01

    The aim of this study was to establish bovine intestinal epithelial cell (BIEC) line and provide a novel clone cell method. Although various strategies of bovine cell culture and clone techniques have been reported, these methods remain not established. Here, we culture successfully primary BIECs and establish a novel clone cell method. Our result showed that BIECs could be successfully cultured and passaged about generation 5. These cellular aggregates and clusters were adherent loosely at day 2 of culture. Cell aggregates and clusters start to proliferate after approximately 4 d. The BIECs showed positive reaction against cytokeratin 18, E-cadherin, and characteristics of epithelial-like morphology. In addition, the fatty acid-binding proteins (FABPs), villin, and intestinal peptidase (IP) band were positive in BIECs. Our results suggest that the establishment of culturing and clone BIEC methods will apply to isolate and clone other primary cells. These BIECs could therefore contribute to the study of bovine intestinal nutrient absorption and regulation, immune regulation, and the pathogenesis of the bovine intestinal disease, which will provide intestinal cell model in vitro.

  1. Modulation of Intestinal Epithelial Permeability in Differentiated Caco-2 Cells Exposed to Aflatoxin M1 and Ochratoxin A Individually or Collectively

    Directory of Open Access Journals (Sweden)

    Yanan Gao

    2017-12-01

    Full Text Available Aflatoxin M1 (AFM1 and ochratoxin A (OTA are mycotoxins commonly found in milk; however, their effects on intestinal epithelial cells have not been reported. In the present study, we show that AFM1 (0.12 and 12 μM and OTA (0.2 and 20 μM individually or collectively increased the paracellular flux of lucifer yellow and fluorescein isothiocyanate (FITC-dextrans (4 and 40 kDa and decreased transepithelial electrical resistance values in differentiated Caco-2 cells after 48 h of exposure, indicating increased epithelial permeability. Immunoblotting and immunofluorescent analysis revealed that AFM1, OTA, and their combination decreased the expression levels of tight junction (TJ proteins and disrupted their structures, namely, claudin-3, claudin-4, occludin, and zonula occludens-1 (ZO-1, and p44/42 mitogen-activated protein kinase (MAPK partially involved in the mycotoxins-induced disruption of intestinal barrier. The effects of a combination of AFM1 and OTA on intestinal barrier function were more significant (p < 0.05 than those of AFM1 and OTA alone, yielding additive or synergistic effects. The additive or synergistic effects of AFM1 and OTA on intestinal barrier function might affect human health, especially in children, and toxin risks should be considered.

  2. Defining new criteria for selection of cell-based intestinal models using publicly available databases

    Directory of Open Access Journals (Sweden)

    Christensen Jon

    2012-06-01

    Full Text Available Abstract Background The criteria for choosing relevant cell lines among a vast panel of available intestinal-derived lines exhibiting a wide range of functional properties are still ill-defined. The objective of this study was, therefore, to establish objective criteria for choosing relevant cell lines to assess their appropriateness as tumor models as well as for drug absorption studies. Results We made use of publicly available expression signatures and cell based functional assays to delineate differences between various intestinal colon carcinoma cell lines and normal intestinal epithelium. We have compared a panel of intestinal cell lines with patient-derived normal and tumor epithelium and classified them according to traits relating to oncogenic pathway activity, epithelial-mesenchymal transition (EMT and stemness, migratory properties, proliferative activity, transporter expression profiles and chemosensitivity. For example, SW480 represent an EMT-high, migratory phenotype and scored highest in terms of signatures associated to worse overall survival and higher risk of recurrence based on patient derived databases. On the other hand, differentiated HT29 and T84 cells showed gene expression patterns closest to tumor bulk derived cells. Regarding drug absorption, we confirmed that differentiated Caco-2 cells are the model of choice for active uptake studies in the small intestine. Regarding chemosensitivity we were unable to confirm a recently proposed association of chemo-resistance with EMT traits. However, a novel signature was identified through mining of NCI60 GI50 values that allowed to rank the panel of intestinal cell lines according to their drug responsiveness to commonly used chemotherapeutics. Conclusions This study presents a straightforward strategy to exploit publicly available gene expression data to guide the choice of cell-based models. While this approach does not overcome the major limitations of such models

  3. Zinc sulfide in intestinal cell granules of Ancylostoma caninum adults

    Energy Technology Data Exchange (ETDEWEB)

    Gianotti, A.J.; Clark, D.T.; Dash, J. (Portland State Univ., OR (USA))

    1991-04-01

    A source of confusion has existed since the turn of the century about the reddish brown, weakly birefringent 'sphaerocrystals' located in the intestines of strongyle nematodes, Strongylus and Ancylostoma. X-ray diffraction and energy dispersive spectrometric analyses were used for accurate determination of the crystalline order and elemental composition of the granules in the canine hookworm Ancylostoma caninum. The composition of the intestinal pigmented granules was identified unequivocally as zinc sulfide. It seems most probable that the granules serve to detoxify high levels of metallic ions (specifically zinc) present due to the large intake of host blood.

  4. Mucosal innate immune cells regulate both gut homeostasis and intestinal inflammation.

    Science.gov (United States)

    Kurashima, Yosuke; Goto, Yoshiyuki; Kiyono, Hiroshi

    2013-12-01

    Continuous exposure of intestinal mucosal surfaces to diverse microorganisms and their metabolites reflects the biological necessity for a multifaceted, integrated epithelial and immune cell-mediated regulatory system. The development and function of the host cells responsible for the barrier function of the intestinal surface (e.g., M cells, Paneth cells, goblet cells, and columnar epithelial cells) are strictly regulated through both positive and negative stimulation by the luminal microbiota. Stimulation by damage-associated molecular patterns and commensal bacteria-derived microbe-associated molecular patterns provokes the assembly of inflammasomes, which are involved in maintaining the integrity of the intestinal epithelium. Mucosal immune cells located beneath the epithelium play critical roles in regulating both the mucosal barrier and the relative composition of the luminal microbiota. Innate lymphoid cells and mast cells, in particular, orchestrate the mucosal regulatory system to create a mutually beneficial environment for both the host and the microbiota. Disruption of mucosal homeostasis causes intestinal inflammation such as that seen in inflammatory bowel disease. Here, we review the recent research on the biological interplay among the luminal microbiota, epithelial cells, and mucosal innate immune cells in both healthy and pathological conditions. © 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Dll1- and Dll4-mediated Notch signaling is required for homeostasis of intestinal stem cells

    Science.gov (United States)

    Pellegrinet, Luca; Rodilla, Veronica; Liu, Zhenyi; Chen, Shuang; Koch, Ute; Espinosa, Lluis; Kaestner, Klaus H.; Kopan, Raphael; Lewis, Julian; Radtke, Freddy

    2011-01-01

    Background & Aims Ablation of Notch signaling within the intestinal epithelium results in loss of proliferating crypt progenitors, due to their conversion into post-mitotic secretory cells. We aimed to confirm that Notch was active in stem cells (SC), investigate consequences of loss of Notch signaling within the intestinal SC compartment, and identify the physiological ligands of Notch in mouse intestine. Furthermore, we investigated whether the induction of goblet cell differentiation that results from loss of Notch requires the transcription factor Krüppel-like factor 4 (Klf4). Methods Trasgenic mice that carried a reporter of Notch1 activation were used for lineage tracing experiments. The in vivo functions of the Notch ligands Jagged1 (Jag1), Delta-like1 (Dll1), Delta-like4 (Dll4), and the transcription factor Klf4 were assessed in mice with inducible, gut-specific gene targeting (Vil-Cre-ERT2). Results Notch1 signaling was found to be activated in intestinal SC. Although deletion of Jag1 or Dll4 did not perturb the intestinal epithelium, inactivation of Dll1 resulted in a moderate increase in number of goblet cells without noticeable effects of progenitor proliferation. However, simultaneous inactivation of Dll1 and Dll4 resulted in the complete conversion of proliferating progenitors into post-mitotic goblet cells, concomitant with loss of SC (Olfm4+, Lgr5+ and Ascl2+). Klf4 inactivation did not interfere with goblet cell differentiation in adult wild-type or in Notch pathway-deficient gut. Conclusions Notch signaling in SC and progenitors is activated by Dll1 and Dll4 ligands and is required for maintenance of intestinal progenitor and SC. Klf4 is dispensable for goblet cell differentiation in intestines of adult Notch-deficient mice. PMID:21238454

  6. Dll1- and dll4-mediated notch signaling are required for homeostasis of intestinal stem cells.

    Science.gov (United States)

    Pellegrinet, Luca; Rodilla, Veronica; Liu, Zhenyi; Chen, Shuang; Koch, Ute; Espinosa, Lluis; Kaestner, Klaus H; Kopan, Raphael; Lewis, Julian; Radtke, Freddy

    2011-04-01

    Ablation of Notch signaling within the intestinal epithelium results in loss of proliferating crypt progenitors due to their conversion into postmitotic secretory cells. We aimed to confirm that Notch was active in stem cells (SCs), investigate consequences of loss of Notch signaling within the intestinal SC compartment, and identify the physiologic ligands of Notch in mouse intestine. Furthermore, we investigated whether the induction of goblet cell differentiation that results from loss of Notch requires the transcription factor Krüppel-like factor 4 (Klf4). Transgenic mice that carried a reporter of Notch1 activation were used for lineage tracing experiments. The in vivo functions of the Notch ligands Jagged1 (Jag1), Delta-like1 (Dll1), Delta-like4 (Dll4), and the transcription factor Klf4 were assessed in mice with inducible, gut-specific gene targeting (Vil-Cre-ER(T2)). Notch1 signaling was found to be activated in intestinal SCs. Although deletion of Jag1 or Dll4 did not perturb the intestinal epithelium, inactivation of Dll1 resulted in a moderate increase in number of goblet cells without noticeable effects of progenitor proliferation. However, simultaneous inactivation of Dll1 and Dll4 resulted in the complete conversion of proliferating progenitors into postmitotic goblet cells, concomitant with loss of SCs (Olfm4(+), Lgr5(+), and Ascl2(+)). Klf4 inactivation did not interfere with goblet cell differentiation in adult wild-type or in Notch pathway-deficient gut. Notch signaling in SCs and progenitors is activated by Dll1 and Dll4 ligands and is required for maintenance of intestinal progenitor and SCs. Klf4 is dispensable for goblet cell differentiation in intestines of adult Notch-deficient mice. Copyright © 2011 AGA Institute. Published by Elsevier Inc. All rights reserved.

  7. Deletion of Foxp3+ regulatory T cells in genetically targeted mice supports development of intestinal inflammation

    Directory of Open Access Journals (Sweden)

    Boehm Franziska

    2012-07-01

    Full Text Available Abstract Background Mice lacking Foxp3+ regulatory T (Treg cells develop severe tissue inflammation in lung, skin, and liver with premature death, whereas the intestine remains uninflamed. This study aims to demonstrate the importance of Foxp3+ Treg for the activation of T cells and the development of intestinal inflammation. Methods Foxp3-GFP-DTR (human diphtheria toxin receptor C57BL/6 mice allow elimination of Foxp3+ Treg by treatment with Dx (diphtheria toxin. The influence of Foxp3+ Treg on intestinal inflammation was tested using the CD4+ T-cell transfer colitis model in Rag−/− C57BL/6 mice and the acute DSS-colitis model. Results Continuous depletion of Foxp3+ Treg in Foxp3-GFP-DTR mice led to dramatic weight loss and death of mice by day 28. After 10 days of depletion of Foxp3+ Treg, isolated CD4+ T-cells were activated and produced extensive amounts of IFN-γ, IL-13, and IL-17A. Transfer of total CD4+ T-cells isolated from Foxp3-GFP-DTR mice did not result in any changes of intestinal homeostasis in Rag−/− C57BL/6 mice. However, administration of DTx between days 14 and 18 after T-cell reconstitution, lead to elimination of Foxp3+ Treg and to immediate weight loss due to intestinal inflammation. This pro-inflammatory effect of Foxp3+ Treg depletion consecutively increased inflammatory cytokine production. Further, the depletion of Foxp3+ Treg from Foxp3-GFP-DTR mice increased the severity of acute dSS-colitis accompanied by 80% lethality of Treg-depleted mice. CD4+ effector T-cells from Foxp3+ Treg-depleted mice produced significantly more pro-inflammatory cytokines. Conclusion Intermittent depletion of Foxp3+ Treg aggravates intestinal inflammatory responses demonstrating the importance of Foxp3+ Treg for the balance at the mucosal surface of the intestine.

  8. Intestinal Epithelial Cell Endoplasmic Reticulum Stress and Inflammatory Bowel Disease Pathogenesis: An Update Review

    Directory of Open Access Journals (Sweden)

    Xiaoshi Ma

    2017-10-01

    Full Text Available The intestinal epithelial cells serve essential roles in maintaining intestinal homeostasis, which relies on appropriate endoplasmic reticulum (ER function for proper protein folding, modification, and secretion. Exogenous or endogenous risk factors with an ability to disturb the ER function can impair the intestinal barrier function and activate inflammatory responses in the host. The last decade has witnessed considerable progress in the understanding of the functional role of ER stress and unfolded protein response (UPR in the gut homeostasis and its significant contribution to the pathogenesis of inflammatory bowel disease (IBD. Herein, we review recent evidence supporting the viewpoint that deregulation of ER stress and UPR signaling in the intestinal epithelium, including the absorptive cells, Paneth cells, goblet cells, and enteroendocrine cells, mediates the action of genetic or environmental factors driving colitis in experimental animals and IBD patients. In addition, we highlight pharmacologic application of chaperones or small molecules that enhance protein folding and modification capacity or improve the function of the ER. These molecules represent potential therapeutic strategies in the prevention or treatment of IBD through restoring ER homeostasis in intestinal epithelial cells.

  9. Irgm1-deficient mice exhibit Paneth cell abnormalities and increased susceptibility to acute intestinal inflammation.

    Science.gov (United States)

    Liu, Bo; Gulati, Ajay S; Cantillana, Viviana; Henry, Stanley C; Schmidt, Elyse A; Daniell, Xiaoju; Grossniklaus, Emily; Schoenborn, Alexi A; Sartor, R Balfour; Taylor, Gregory A

    2013-10-15

    Crohn's disease (CD) is a chronic, immune-mediated, inflammatory disorder of the intestine that has been linked to numerous susceptibility genes, including the immunity-related GTPase (IRG) M (IRGM). IRGs comprise a family of proteins known to confer resistance to intracellular infections through various mechanisms, including regulation of phagosome processing, cell motility, and autophagy. However, despite its association with CD, the role of IRGM and other IRGs in regulating intestinal inflammation is unclear. We investigated the involvement of Irgm1, an ortholog of IRGM, in the genesis of murine intestinal inflammation. After dextran sodium sulfate exposure, Irgm1-deficient [Irgm1 knockout (KO)] mice showed increased acute inflammation in the colon and ileum, with worsened clinical responses. Marked alterations of Paneth cell location and granule morphology were present in Irgm1 KO mice, even without dextran sodium sulfate exposure, and were associated with impaired mitophagy and autophagy in Irgm1 KO intestinal cells (including Paneth cells). This was manifested by frequent tubular and swollen mitochondria and increased LC3-positive autophagic structures. Interestingly, these LC3-positive structures often contained Paneth cell granules. These results suggest that Irgm1 modulates acute inflammatory responses in the mouse intestine, putatively through the regulation of gut autophagic processes, that may be pivotal for proper Paneth cell functioning.

  10. Protein kinase D stabilizes aldosterone-induced ERK1/2 MAP kinase activation in M1 renal cortical collecting duct cells to promote cell proliferation.

    LENUS (Irish Health Repository)

    McEneaney, Victoria

    2010-01-01

    Aldosterone elicits transcriptional responses in target tissues and also rapidly stimulates the activation of protein kinase signalling cascades independently of de novo protein synthesis. Here we investigated aldosterone-induced cell proliferation and extra-cellular regulated kinase 1 and 2 (ERK1\\/2) mitogen activated protein (MAP) kinase signalling in the M1 cortical collecting duct cell line (M1-CCD). Aldosterone promoted the proliferative growth of M1-CCD cells, an effect that was protein kinase D1 (PKD1), PKCdelta and ERK1\\/2-dependent. Aldosterone induced the rapid activation of ERK1\\/2 with peaks of activation at 2 and 10 to 30 min after hormone treatment followed by sustained activation lasting beyond 120 min. M1-CCD cells suppressed in PKD1 expression exhibited only the early, transient peaks in ERK1\\/2 activation without the sustained phase. Aldosterone stimulated the physical association of PKD1 with ERK1\\/2 within 2 min of treatment. The mineralocorticoid receptor (MR) antagonist RU28318 inhibited the early and late phases of aldosterone-induced ERK1\\/2 activation, and also aldosterone-induced proliferative cell growth. Aldosterone induced the sub-cellular redistribution of ERK1\\/2 to the nuclei at 2 min and to cytoplasmic sites, proximal to the nuclei after 30 min. This sub-cellular distribution of ERK1\\/2 was inhibited in cells suppressed in the expression of PKD1.

  11. Perforated small intestine in a patient with T-cell lymphoma; a rare cause of peritonitis

    Directory of Open Access Journals (Sweden)

    Petrişor Banu

    2016-04-01

    Full Text Available The nontraumatic perforations of the small intestine are pathological entities with particular aspects in respect to diagnosis and treatment. These peculiarities derive from the nonspecific clinical expression of the peritonitis syndrome, and from the multitude of causes that might be the primary sources of the perforation: foreign bodies, inflammatory diseases, tumors, infectious diseases, etc. Accordingly, in most cases intestinal perforation is discovered only by laparotomy and the definitive diagnosis is available only after histopathologic examination. Small bowel malignancies are rare; among them, lymphomas rank third in frequency, being mostly B-cell non Hodgkin lymphomas. Only 10% of non-Hodgkin lymphomas are with T-cell. We report the case of a 57 years’ old woman with intestinal T-cell lymphoma, whose first clinical symptomatology was related to a complication represented by perforation of the small intestine. Laparotomy performed in emergency identified an ulcerative lesion with perforation in the jejunum, which required segmental enterectomy with anastomosis. The nonspecific clinical manifestations of intestinal lymphomas make from diagnosis a difficult procedure. Due to the fact that surgery does not have a definite place in the treatment of the small intestinal lymphomas (for cases complicated with perforation, and beyond the morbidity associated with the surgery performed in emergency conditions, prognosis of these patients is finally given by the possibility to control the systemic disease through adjuvant therapy.

  12. Nlrp9b inflammasome restricts rotavirus infection in intestinal epithelial cells.

    Science.gov (United States)

    Zhu, Shu; Ding, Siyuan; Wang, Penghua; Wei, Zheng; Pan, Wen; Palm, Noah W; Yang, Yi; Yu, Hua; Li, Hua-Bing; Wang, Geng; Lei, Xuqiu; de Zoete, Marcel R; Zhao, Jun; Zheng, Yunjiang; Chen, Haiwei; Zhao, Yujiao; Jurado, Kellie A; Feng, Ningguo; Shan, Liang; Kluger, Yuval; Lu, Jun; Abraham, Clara; Fikrig, Erol; Greenberg, Harry B; Flavell, Richard A

    2017-06-29

    Rotavirus, a leading cause of severe gastroenteritis and diarrhoea in young children, accounts for around 215,000 deaths annually worldwide. Rotavirus specifically infects the intestinal epithelial cells in the host small intestine and has evolved strategies to antagonize interferon and NF-κB signalling, raising the question as to whether other host factors participate in antiviral responses in intestinal mucosa. The mechanism by which enteric viruses are sensed and restricted in vivo, especially by NOD-like receptor (NLR) inflammasomes, is largely unknown. Here we uncover and mechanistically characterize the NLR Nlrp9b that is specifically expressed in intestinal epithelial cells and restricts rotavirus infection. Our data show that, via RNA helicase Dhx9, Nlrp9b recognizes short double-stranded RNA stretches and forms inflammasome complexes with the adaptor proteins Asc and caspase-1 to promote the maturation of interleukin (Il)-18 and gasdermin D (Gsdmd)-induced pyroptosis. Conditional depletion of Nlrp9b or other inflammasome components in the intestine in vivo resulted in enhanced susceptibility of mice to rotavirus replication. Our study highlights an important innate immune signalling pathway that functions in intestinal epithelial cells and may present useful targets in the modulation of host defences against viral pathogens.

  13. Nlrp9b inflammasome restricts rotavirus infection in intestinal epithelial cells

    Science.gov (United States)

    Zhu, Shu; Ding, Siyuan; Wang, Penghua; Wei, Zheng; Pan, Wen; Palm, Noah W; Yang, Yi; Yu, Hua; Li, Hua-Bing; Wang, Geng; Lei, Xuqiu; de Zoete, Marcel R.; Zhao, Jun; Zheng, Yunjiang; Chen, Haiwei; Zhao, Yujiao; Jurado, Kellie A.; Feng, Ningguo; Shan, Liang; Kluger, Yuval; Lu, Jun; Abraham, Clara; Fikrig, Erol; Greenberg, Harry B.; Flavell, Richard A.

    2018-01-01

    Rotavirus, a leading cause of severe gastroenteritis and diarrhoea in young children, accounts for around 215,000 deaths annually worldwide1. Rotavirus specifically infects the intestinal epithelial cells in the host small intestine and has evolved strategies to antagonize interferon and NF-κB signalling2–5, raising the question as to whether other host factors participate in antiviral responses in intestinal mucosa. The mechanism by which enteric viruses are sensed and restricted in vivo, especially by NOD-like receptor (NLR) inflammasomes, is largely unknown. Here we uncover and mechanistically characterize the NLR Nlrp9b that is specifically expressed in intestinal epithelial cells and restricts rotavirus infection. Our data show that, via RNA helicase Dhx9, Nlrp9b recognizes short double-stranded RNA stretches and forms inflammasome complexes with the adaptor proteins Asc and caspase-1 to promote the maturation of interleukin (Il)-18 and gasdermin D (Gsdmd)-induced pyroptosis. Conditional depletion of Nlrp9b or other inflammasome components in the intestine in vivo resulted in enhanced susceptibility of mice to rotavirus replication. Our study highlights an important innate immune signalling pathway that functions in intestinal epithelial cells and may present useful targets in the modulation of host defences against viral pathogens. PMID:28636595

  14. Divergent Roles of Interferon-γ and Innate Lymphoid Cells in Innate and Adaptive Immune Cell-Mediated Intestinal Inflammation.

    Science.gov (United States)

    Brasseit, Jennifer; Kwong Chung, Cheong K C; Noti, Mario; Zysset, Daniel; Hoheisel-Dickgreber, Nina; Genitsch, Vera; Corazza, Nadia; Mueller, Christoph

    2018-01-01

    Aberrant interferon gamma (IFNγ) expression is associated with the pathogenesis of numerous autoimmune- and inflammatory disorders, including inflammatory bowel diseases (IBD). However, the requirement of IFNγ for the pathogenesis of chronic intestinal inflammation remains controversial. The aim of this study was thus to investigate the role of IFNγ in experimental mouse models of innate and adaptive immune cell-mediated intestinal inflammation using genetically and microbiota-stabilized hosts. While we find that IFNγ drives acute intestinal inflammation in the anti-CD40 colitis model in an innate lymphoid cell (ILC)-dependent manner, IFNγ secreted by both transferred CD4 T cells and/or cells of the lymphopenic Rag1 -/- recipient mice was dispensable for CD4 T cell-mediated colitis. In the absence of IFNγ, intestinal inflammation in CD4 T cell recipient mice was associated with enhanced IL17 responses; consequently, targeting IL17 signaling in IFNγ-deficient mice reduced T cell-mediated colitis. Intriguingly, in contrast to the anti-CD40 model of colitis, depletion of ILC in the Rag1 -/- recipients of colitogenic CD4 T cells did not prevent induction of colonic inflammation. Together, our findings demonstrate that IFNγ represents an essential, or a redundant, pro-inflammatory cytokine for the induction of intestinal inflammation, depending on the experimental mouse model used and on the nature of the critical disease inducing immune cell populations involved.

  15. Wnt signaling in adult intestinal stem cells and cancer

    Czech Academy of Sciences Publication Activity Database

    Krausová, Michaela; Kořínek, Vladimír

    2014-01-01

    Roč. 26, č. 3 (2014), s. 570-579 ISSN 0898-6568 R&D Projects: GA ČR GAP305/12/2347; GA ČR GAP305/11/1780 Institutional support: RVO:68378050 Keywords : Wnt * intestine * cancer Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.315, year: 2014

  16. Radiosensitivity of mice of different lines and age as determinated with reference to ''intestinal'' death and DNA repair in intestinal epithelium cells

    Energy Technology Data Exchange (ETDEWEB)

    Konoplyannikova, O.A.; Sklobovskaya, M.V.; Konoplyannikov, A.G.; Saenko, A.S. (Akademiya Meditsinskikh Nauk SSSR, Obninsk. Nauchno-Issledovatel' skij Inst. Meditsinskoj Radiologii)

    A study was made of the influence of strain- and age-related differences on mouse mortality after irradiation with doses lying within the ''intestinal'' dose range, and also damages to stem cells of intestinal epithelium and induction and repair of single-strand DNA breaks in intestinal epitherium cells. Mice of different lines and age vary in LDsub(50/4) and stem cell radiosensitivity. There are no differences in the sedimentation constants of DNA fragments in alkaline lysates of intestinal crypts of intact mice of different age. Radiosensitivity determined with reference to single-strand breaks induction in DNA is similar with different mouse groups. Repair of single-strand DNA breaks of elderly mice is slower than that of young animals.

  17. Analysis of interactions of Salmonella type three secretion mutants with 3-D intestinal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Andrea L Radtke

    Full Text Available The prevailing paradigm of Salmonella enteropathogenesis based on monolayers asserts that Salmonella pathogenicity island-1 Type Three Secretion System (SPI-1 T3SS is required for bacterial invasion into intestinal epithelium. However, little is known about the role of SPI-1 in mediating gastrointestinal disease in humans. Recently, SPI-1 deficient nontyphoidal Salmonella strains were isolated from infected humans and animals, indicating that SPI-1 is not required to cause enteropathogenesis and demonstrating the need for more in vivo-like models. Here, we utilized a previously characterized 3-D organotypic model of human intestinal epithelium to elucidate the role of all characterized Salmonella enterica T3SSs. Similar to in vivo reports, the Salmonella SPI-1 T3SS was not required to invade 3-D intestinal cells. Additionally, Salmonella strains carrying single (SPI-1 or SPI-2, double (SPI-1/2 and complete T3SS knockout (SPI-1/SPI-2: flhDC also invaded 3-D intestinal cells to wildtype levels. Invasion of wildtype and TTSS mutants was a Salmonella active process, whereas non-invasive bacterial strains, bacterial size beads, and heat-killed Salmonella did not invade 3-D cells. Wildtype and T3SS mutants did not preferentially target different cell types identified within the 3-D intestinal aggregates, including M-cells/M-like cells, enterocytes, or Paneth cells. Moreover, each T3SS was necessary for substantial intracellular bacterial replication within 3-D cells. Collectively, these results indicate that T3SSs are dispensable for Salmonella invasion into highly differentiated 3-D models of human intestinal epithelial cells, but are required for intracellular bacterial growth, paralleling in vivo infection observations and demonstrating the utility of these models in predicting in vivo-like pathogenic mechanisms.

  18. Culture media from hypoxia conditioned endothelial cells protect human intestinal cells from hypoxia/reoxygenation injury.

    Science.gov (United States)

    Hummitzsch, Lars; Zitta, Karina; Bein, Berthold; Steinfath, Markus; Albrecht, Martin

    2014-03-10

    Remote ischemic preconditioning (RIPC) is a phenomenon, whereby short episodes of non-lethal ischemia to an organ or tissue exert protection against ischemia/reperfusion injury in a distant organ. However, there is still an apparent lack of knowledge concerning the RIPC-mediated mechanisms within the target organ and the released factors. Here we established a human cell culture model to investigate cellular and molecular effects of RIPC and to identify factors responsible for RIPC-mediated intestinal protection. Human umbilical vein cells (HUVEC) were exposed to repeated episodes of hypoxia (3 × 15 min) and conditioned culture media (CM) were collected after 24h. Human intestinal cells (CaCo-2) were cultured with or without CM and subjected to 90 min of hypoxia/reoxygenation injury. Reverse transcription-polymerase chain reaction, Western blotting, gelatin zymography, hydrogen peroxide measurements and lactate dehydrogenase (LDH) assays were performed. In HUVEC cultures hypoxic conditioning did not influence the profile of secreted proteins but led to an increased gelatinase activity (Pcultures 90 min of hypoxia/reoxygenation resulted in morphological signs of cell damage, increased LDH levels (Pculture model may help to unravel RIPC-mediated cellular events and to identify molecules released by RIPC. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Dclk1+ small intestinal epithelial tuft cells display the hallmarks of quiescence and self-renewal

    Science.gov (United States)

    Chandrakesan, Parthasarathy; May, Randal; Qu, Dongfeng; Weygant, Nathaniel; Taylor, Vivian E.; Li, James D.; Ali, Naushad; Sureban, Sripathi M.; Qante, Michael; Wang, Timothy C.; Bronze, Michael S.; Houchen, Courtney W.

    2015-01-01

    To date, no discrete genetic signature has been defined for isolated Dclk1+ tuft cells within the small intestine. Furthermore, recent reports on the functional significance of Dclk1+ cells in the small intestine have been inconsistent. These cells have been proposed to be fully differentiated cells, reserve stem cells, and tumor stem cells. In order to elucidate the potential function of Dclk1+ cells, we FACS-sorted Dclk1+ cells from mouse small intestinal epithelium using transgenic mice expressing YFP under the control of the Dclk1 promoter (Dclk1-CreER;Rosa26-YFP). Analysis of sorted YFP+ cells demonstrated marked enrichment (~6000 fold) for Dclk1 mRNA compared with YFP− cells. Dclk1+ population display ~6 fold enrichment for the putative quiescent stem cell marker Bmi1. We observed significantly greater expression of pluripotency genes, pro-survival genes, and quiescence markers in the Dclk1+ population. A significant increase in self-renewal capability (14-fold) was observed in in vitro isolated Dclk1+ cells. The unique genetic report presented in this manuscript suggests that Dclk1+ cells may maintain quiescence, pluripotency, and metabolic activity for survival/longevity. Functionally, these reserve characteristics manifest in vitro, with Dclk1+ cells exhibiting greater ability to self-renew. These findings indicate that quiescent stem-like functionality is a feature of Dclk1-expressing tuft cells. PMID:26362399

  20. Mast cells play no role in the pathogenesis of postoperative ileus induced by intestinal manipulation.

    Science.gov (United States)

    Gomez-Pinilla, Pedro J; Farro, Giovanna; Di Giovangiulio, Martina; Stakenborg, Nathalie; Némethova, Andrea; de Vries, Annick; Liston, Adrian; Feyerabend, Thorsten B; Rodewald, Hans-Reimer; Rodewald, Hans-Reimwer; Boeckxstaens, Guy E; Matteoli, Gianluca

    2014-01-01

    Intestinal manipulation (IM) during abdominal surgery results in intestinal inflammation leading to hypomotility or ileus. Mast cell activation is thought to play a crucial role in the pathophysiology of postoperative ileus (POI). However, this conclusion was mainly drawn using mast cell-deficient mouse models with abnormal Kit signaling. These mice also lack interstitial cells of Cajal (ICC) resulting in aberrant gastrointestinal motility even prior to surgery, compromising their use as model to study POI. To avoid these experimental weaknesses we took advantage of a newly developed knock-in mouse model, Cpa3(Cre/+) , devoid of mast cells but with intact Kit signaling. The role of mast cells in the development of POI and intestinal inflammation was evaluated assessing gastrointestinal transit and muscularis externa inflammation after IM in two strains of mice lacking mast cells, i.e. Kit(W-sh/W-sh) and Cpa3(Cre/+) mice, and by use of the mast cell stabilizer cromolyn. Kit(W-sh/W-sh) mice lack ICC networks and already revealed significantly delayed gastrointestinal transit even before surgery. IM did not further delay intestinal transit, but induced infiltration of myeloperoxidase positive cells, expression of inflammatory cytokines and recruitment of monocytes and neutrophils into the muscularis externa. On the contrary, Cpa3(Cre/+) mice have a normal network of ICC and normal gastrointestinal. Surprisingly, IM in Cpa3(Cre/+) mice caused delay in gut motility and intestinal inflammation as in wild type littermates mice (Cpa3(+/+) ). Furthermore, treatment with the mast cell inhibitor cromolyn resulted in an inhibition of mast cells without preventing POI. Here, we confirm that IM induced mast cell degranulation. However, our data demonstrate that mast cells are not required for the pathogenesis of POI in mice. Although there might be species differences between mouse and human, our results argue against mast cell inhibitors as a therapeutic approach to shorten POI.

  1. Mast cells play no role in the pathogenesis of postoperative ileus induced by intestinal manipulation.

    Directory of Open Access Journals (Sweden)

    Pedro J Gomez-Pinilla

    Full Text Available INTRODUCTION: Intestinal manipulation (IM during abdominal surgery results in intestinal inflammation leading to hypomotility or ileus. Mast cell activation is thought to play a crucial role in the pathophysiology of postoperative ileus (POI. However, this conclusion was mainly drawn using mast cell-deficient mouse models with abnormal Kit signaling. These mice also lack interstitial cells of Cajal (ICC resulting in aberrant gastrointestinal motility even prior to surgery, compromising their use as model to study POI. To avoid these experimental weaknesses we took advantage of a newly developed knock-in mouse model, Cpa3(Cre/+ , devoid of mast cells but with intact Kit signaling. DESIGN: The role of mast cells in the development of POI and intestinal inflammation was evaluated assessing gastrointestinal transit and muscularis externa inflammation after IM in two strains of mice lacking mast cells, i.e. Kit(W-sh/W-sh and Cpa3(Cre/+ mice, and by use of the mast cell stabilizer cromolyn. RESULTS: Kit(W-sh/W-sh mice lack ICC networks and already revealed significantly delayed gastrointestinal transit even before surgery. IM did not further delay intestinal transit, but induced infiltration of myeloperoxidase positive cells, expression of inflammatory cytokines and recruitment of monocytes and neutrophils into the muscularis externa. On the contrary, Cpa3(Cre/+ mice have a normal network of ICC and normal gastrointestinal. Surprisingly, IM in Cpa3(Cre/+ mice caused delay in gut motility and intestinal inflammation as in wild type littermates mice (Cpa3(+/+ . Furthermore, treatment with the mast cell inhibitor cromolyn resulted in an inhibition of mast cells without preventing POI. CONCLUSIONS: Here, we confirm that IM induced mast cell degranulation. However, our data demonstrate that mast cells are not required for the pathogenesis of POI in mice. Although there might be species differences between mouse and human, our results argue against mast

  2. Loss of Sonic hedgehog leads to alterations in intestinal secretory cell maturation and autophagy.

    Directory of Open Access Journals (Sweden)

    Jessica Gagné-Sansfaçon

    Full Text Available BACKGROUND: Intestinal epithelial cells express the Sonic and Indian hedgehog ligands. Despite the strong interest in gut hedgehog signaling in GI diseases, no studies have specifically addressed the singular role of intestinal epithelial cell Sonic hedgehog signaling. The aim of this study was to investigate the specific role of Sonic hedgehog in adult ileal epithelial homeostasis. METHODOLOGY/PRINCIPAL FINDINGS: A Sonic hedgehog intestinal epithelial conditional knockout mouse model was generated. Assessment of ileal histological abnormalities, crypt epithelial cell proliferation, epithelial cell fate, junctional proteins, signaling pathways, as well as ultrastructural analysis of intracellular organelles were performed in control and mutant mice. Mice lacking intestinal epithelial Sonic Hedgehog displayed decreased ileal crypt/villus length, decreased crypt proliferation as well as a decrease in the number of ileal mucin-secreting goblet cells and antimicrobial peptide-secreting Paneth cells during adult life. These secretory cells also exhibited disruption of their secretory products in mutant mice. Ultrastructural microscopy analysis revealed a dilated ER lumen in secretory cells. This phenotype was also associated with a decrease in autophagy. CONCLUSIONS/SIGNIFICANCE: Altogether, these findings indicate that the loss of Sonic hedgehog can lead to ileal secretory cell modifications indicative of endoplasmic reticulum stress, accompanied by a significant reduction in autophagy.

  3. Precision-cut intestinal slices as a culture system to analyze the infection of differentiated intestinal epithelial cells by avian influenza viruses.

    Science.gov (United States)

    Punyadarsaniya, Darsaniya; Winter, Christine; Mork, Ann-Kathrin; Amiri, Mahdi; Naim, Hassan Y; Rautenschlein, Silke; Herrler, Georg

    2015-02-01

    Many viruses infect and replicate in their host via the intestinal tract, e.g. many picornaviruses, several coronaviruses and avian influenza viruses of waterfowl. To analyze infection of enterocytes is a challenging task as culture systems for differentiated intestinal epithelial cells are not readily available and often have a life span that is too short for infection studies. Precision-cut intestinal slices (PCIS) from chicken embryos were prepared and shown that the epithelial cells lining the lumen of the intestine are viable for up to 4 days. Using lectin staining, it was demonstrated that α2,3-linked sialic acids, the preferred receptor determinants of avian influenza viruses, are present on the apical side of the epithelial cells. Furthermore, the epithelial cells (at the tips) of the villi were shown to be susceptible to infection by an avian influenza virus of the H9N2 subtype. This culture system will be useful to analyze virus infection of intestinal epithelial cells and it should be applicable also to the intestine of other species. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. ARF6, PI3-kinase and host cell actin cytoskeleton in Toxoplasma gondii cell invasion

    International Nuclear Information System (INIS)

    Vieira da Silva, Claudio; Alves da Silva, Erika; Costa Cruz, Mario; Chavrier, Philippe; Arruda Mortara, Renato

    2009-01-01

    Toxoplasma gondii infects a variety of different cell types in a range of different hosts. Host cell invasion by T. gondii occurs by active penetration of the host cell, a process previously described as independent of host actin polymerization. Also, the parasitophorous vacuole has been shown to resist fusion with endocytic and exocytic pathways of the host cell. ADP-ribosylation factor-6 (ARF6) belongs to the ARF family of small GTP-binding proteins. ARF6 regulates membrane trafficking and actin cytoskeleton rearrangements at the plasma membrane. Here, we have observed that ARF6 is recruited to the parasitophorous vacuole of tachyzoites of T. gondii RH strain and it also plays an important role in the parasite cell invasion with activation of PI3-kinase and recruitment of PIP 2 and PIP 3 to the parasitophorous vacuole of invading parasites. Moreover, it was verified that maintenance of host cell actin cytoskeleton integrity is important to parasite invasion.

  5. Metabolic changes during B cell differentiation for the production of intestinal IgA antibody.

    Science.gov (United States)

    Kunisawa, Jun

    2017-04-01

    To sustain the bio-energetic demands of growth, proliferation, and effector functions, the metabolism of immune cells changes dramatically in response to immunologic stimuli. In this review, I focus on B cell metabolism, especially regarding the production of intestinal IgA antibody. Accumulating evidence has implicated not only host-derived factors (e.g., cytokines) but also gut environmental factors, including the possible involvement of commensal bacteria and diet, in the control of B cell metabolism during intestinal IgA antibody production. These findings yield new insights into the regulation of immunosurveillance and homeostasis in the gut.

  6. Distinct ATOH1 and Neurog3 requirements define tuft cells as a new secretory cell type in the intestinal epithelium

    NARCIS (Netherlands)

    Gerbe, F.; van Es, J.H.; Makrini, L.; Brulin, B.; Mellitzer, G.; Robine, S.; Romagnolo, B.; Shroyer, N.F.; Bourgaux, J.F.; Pignodel, C.; Clevers, H.; Jay, P.

    2011-01-01

    The unique morphology of tuft cells was first revealed by electron microscopy analyses in several endoderm-derived epithelia. Here, we explore the relationship of these cells with the other cell types of the intestinal epithelium and describe the first marker signature allowing their unambiguous

  7. Arthritis by autoreactive T cell lines obtained from rats after injection of intestinal bacterial cell wall fragments

    NARCIS (Netherlands)

    I. Klasen (Ina); J. Kool (Jeanette); M.J. Melief (Marie-José); I. Loeve (I.); W.B. van den Berg (Wim); A.J. Severijnen; M.P.H. Hazenberg (Maarten)

    1992-01-01

    markdownabstract__Abstract__ T cell lines (B13, B19) were isolated from the lymph nodes of Lewis rats 12 days after an arthritogenic injection of cell wall fragments of Eubacterium aerofaciens (ECW), a major resident of the human intestinal flora. These cell wall fragments consist of

  8. Whey protein concentrate enhances intestinal integrity and influences transforming growth factor-β1 and mitogen-activated protein kinase signalling pathways in piglets after lipopolysaccharide challenge.

    Science.gov (United States)

    Xiao, Kan; Jiao, Lefei; Cao, Shuting; Song, Zehe; Hu, Caihong; Han, Xinyan

    2016-03-28

    Whey protein concentrate (WPC) has been reported to have protective effects on the intestinal barrier. However, the molecular mechanisms involved are not fully elucidated. Transforming growth factor-β1 (TGF-β1) is an important component in the WPC, but whether TGF-β1 plays a role in these processes is not clear. The aim of this study was to investigate the protective effects of WPC on the intestinal epithelial barrier as well as whether TGF-β1 is involved in these protection processes in a piglet model after lipopolysaccharide (LPS) challenge. In total, eighteen weanling pigs were randomly allocated to one of the following three treatment groups: (1) non-challenged control and control diet; (2) LPS-challenged control and control diet; (3) LPS+5 %WPC diet. After 19 d of feeding with control or 5 %WPC diets, pigs were injected with LPS or saline. At 4 h after injection, pigs were killed to harvest jejunal samples. The results showed that WPC improved (Pprotein, phosphorylated-Smad2 expression and Smad4 and Smad7 mRNA expressions and decreased (Pprotein kinase signalling pathways.

  9. Actions of vasoactive intestinal peptide and secretin on chief cells prepared from guinea pig stomach

    International Nuclear Information System (INIS)

    Sutliff, V.E.; Raufman, J.P.; Jensen, R.T.; Gardner, J.D.

    1986-01-01

    Vasoactive intestinal peptide and secretin increased cellular cAMP and pepsinogen secretion in dispersed chief cells from guinea pig gastric mucosa. With each peptide there was a close correlation between the dose-response curve for changes in cellular cAMP and that for changes in pepsinogen secretion. Vasoactive intestinal peptide- (10-28) and secretin- (5-27) had no agonist activity and antagonized the actions of vasoactive intestinal peptide and secretin on cellular cAMP and pepsinogen secretion. Studies of binding of 125 I-vasoactive intestinal peptide and of 125 -secretin indicated that gastric chief cells possess four classes of binding sites for vasoactive intestinal peptide and secretin and that occupation of two of these classes of binding sites correlates with the abilities of vasoactive intestinal peptide and secretin to increase cellular cAMP and pepsinogen secretion. What function, in any, is mediated by occupation by the other two classes of binding sites remains to be determined

  10. Crypt base columnar stem cells in small intestines of mice are radioresistant

    NARCIS (Netherlands)

    Hua, G.; Thin, T.H.; Feldman, R.; Haimovitz-Friedman, A.; Clevers, H.; Fuks, Z.; Kolesnick, R.

    2012-01-01

    BACKGROUND & AIMS: Adult stem cells have been proposed to be quiescent and radiation resistant, repairing DNA double-strand breaks by nonhomologous end joining. However, the population of putative small intestinal stem cells (ISCs) at position +4 from the crypt base contradicts this model, in that

  11. Stem cell factor enhances the survival of murine intestinal stem cells after photon irradiation

    International Nuclear Information System (INIS)

    Leigh, B.R.; Khan, W.; Hancock, S.L.

    1995-01-01

    Recombinant rat stem cell factor (SCF) has been shown to decrease lethality in mice exposed to total-body irradiation (TBI) in the lower range of lethality through radioprotection of hematopoietic stem cells and acceleration of bone marrow repopulation. This study evaluates the effect of SCF on the survival of the intestinal mucosal stem cell after TBI. This non-hematopoietic cell is clinically relevant. Gastrointestinal toxicity is common during and after abdominal and pelvic radiation therapy and limits the radiation dose in these regions. As observed with bone marrow, the administration of SCF to mice prior to TBI enhanced the survival of mouse duodenal crypt stem cells. The maximum enhancement of survival was seen when 100 μ/kg of SCF was given intraperitoneally 8 h before irradiation. This regimen increased the survival of duodenal crypt stem cells after 12.0 Gy TBI from 22.5 ± 0.7 per duodenal cross section for controls to 30.0 ± 1.7 after treatment with SCF (P=0.03). The TBI dose producing 50% mortality of 6 days (LD 50/6 ) was increased from 14.9 Gy for control mice to 19.0 Gy for mice treated with SCF (dose modification factor = 1.28). These findings demonstrate that SCF (dose modification factor = 1.28). These findings demonstrate that SCF has radioprotective effects on a non-hematopoietic stem cell population and suggest that SCF may be of clinical value in preventing radiation injury to the intestine. 29 refs., 4 figs

  12. Neural cell adhesion molecule-stimulated neurite outgrowth depends on activation of protein kinase C and the Ras-mitogen-activated protein kinase pathway

    DEFF Research Database (Denmark)

    Kolkova, K; Novitskaya, V; Pedersen, N

    2000-01-01

    , inhibitors of the nonreceptor tyrosine kinase p59(fyn), PLC, PKC and MEK and an activator of PKC, phorbol-12-myristate-13-acetate (PMA). MEK2 transfection rescued cells treated with all inhibitors. The same was found for PMA treatment, except when cells concomitantly were treated with the MEK inhibitor....... Arachidonic acid rescued cells treated with antibodies to the FGF receptor or the PLC inhibitor, but not cells in which the activity of PKC, p59(fyn), FAK, Ras, or MEK was inhibited. Interaction of NCAM with a synthetic NCAM peptide ligand, known to induce neurite outgrowth, was shown to stimulate...... phosphorylation of the MAP kinases extracellular signal-regulated kinases ERK1 and ERK2. The MAP kinase activation was sustained, because ERK1 and ERK2 were phosphorylated in PC12-E2 cells and primary hippocampal neurons even after 24 hr of cultivation on NCAM-expressing fibroblasts. Based on these results, we...

  13. Selective elimination of neuroblastoma cells by synergistic effect of Akt kinase inhibitor and tetrathiomolybdate.

    Science.gov (United States)

    Navrátilová, Jarmila; Karasová, Martina; Kohutková Lánová, Martina; Jiráková, Ludmila; Budková, Zuzana; Pacherník, Jiří; Šmarda, Jan; Beneš, Petr

    2017-09-01

    Neuroblastoma is the most common extracranial solid tumour of infancy. Pathological activation of glucose consumption, glycolysis and glycolysis-activating Akt kinase occur frequently in neuroblastoma cells, and these changes correlate with poor prognosis of patients. Therefore, several inhibitors of glucose utilization and the Akt kinase activity are in preclinical trials as potential anti-cancer drugs. However, metabolic plasticity of cancer cells might undermine efficacy of this approach. In this work, we identified oxidative phosphorylation as compensatory mechanism preserving viability of neuroblastoma cells with inhibited glucose uptake/Akt kinase. It was oxidative phosphorylation that maintained intracellular level of ATP and proliferative capacity of these cells. The oxidative phosphorylation inhibitors (rotenone, tetrathiomolybdate) synergized with inhibitor of the Akt kinase/glucose uptake in down-regulation of both viability of neuroblastoma cells and clonogenic potential of cells forming neuroblastoma spheroids. Interestingly, tetrathiomolybdate acted as highly specific inhibitor of oxygen consumption and activator of lactate production in neuroblastoma cells, but not in normal fibroblasts and neuronal cells. Moreover, the reducing effect of tetrathiomolybdate on cell viability and the level of ATP in the cells with inhibited Akt kinase/glucose uptake was also selective for neuroblastoma cells. Therefore, efficient elimination of neuroblastoma cells requires inhibition of both glucose uptake/Akt kinase and oxidative phosphorylation activities. The use of tetrathiomolybdate as a mitochondrial inhibitor contributes to selectivity of this combined treatment, preferentially targeting neuroblastoma cells. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  14. Modulation of Pacemaker Potentials by Pyungwi-San in Interstitial Cells of Cajal from Murine Small Intestine - Pyungwi-San and Interstitial Cells of Cajal -

    Directory of Open Access Journals (Sweden)

    Kim Jung Nam

    2013-03-01

    Full Text Available Objective: Pyungwi-san (PWS plays a role in a number of physiologic and pharmacologic functions in many organs. Interstitial cells of Cajal (ICCs are pacemaker cells that generate slow waves in the gastrointestinal (GI tract. We aimed to investigate the beneficial effects of PWS in mouse small-intestinal ICCs. Methods: Enzymatic digestion was used to dissociate ICCs from the small intestine of a mouse. The wholecell patch-clamp configuration was used to record membrane potentials from the cultured ICCs. Results: ICCs generated pacemaker potentials in the GI tract. PWS produced membrane depolarization in the current clamp mode. Pretreatment with a Ca2+-free solution and a thapsigargin, a Ca2+-ATPase, inhibitor in the endoplasmic reticulum, eliminated the generation of pacemaker potentials. However, only when the thapsigargin was applied in a bath solution, the membrane depolarization was not produced by PWS. Furthermore, the membrane depolarizations due to PWS were inhibited not by U-73122, an active phospholipase C inhibitor, but by chelerythrine and calphostin C, protein kinase C inhibitors. Conclusions: These results suggest that PWS might affect GI motility by modulating the pacemaker activity in the ICCs.

  15. Tolerogenic CX3CR1+ B cells suppress food allergy-induced intestinal inflammation in mice.

    Science.gov (United States)

    Liu, Z Q; Wu, Y; Song, J P; Liu, X; Liu, Z; Zheng, P Y; Yang, P C

    2013-10-01

    B lymphocytes are an important cell population of the immune regulation; their role in the regulation of food allergy has not been fully understood yet. This study aims to investigate the role of a subpopulation of tolerogenic B cells (TolBC) in the generation of regulatory T cells (Treg) and in the suppression of food allergy-induced intestinal inflammation in mice. The intestinal mucosa-derived CD5+ CD19+ CX3CR1+ TolBCs were characterized by flow cytometry; a mouse model of intestinal T helper (Th)2 inflammation was established to assess the immune regulatory role of this subpopulation of TolBCs. A subpopulation of CD5+ CD19+ CX3CR1+ B cells was detected in the mouse intestinal mucosa. The cells also expressed transforming growth factor (TGF)-β and carried integrin alpha v beta 6 (αvβ6). Exposure to recombinant αvβ6 and anti-IgM antibody induced naive B cells to differentiate into the TGF-β-producing TolBCs. Coculturing this subpopulation of TolBCs with Th0 cells generated CD4+ CD25+ Foxp3+ Tregs. Adoptive transfer with the TolBCs markedly suppressed the food allergy-induced intestinal Th2 pattern inflammation in mice. CD5+ CD19+ CX3CR1+ TolBCs are capable of inducing Tregs in the intestine and suppress food allergy-related Th2 pattern inflammation in mice. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Radiation, an ideal cytotoxic for the study of cell biology in the small intestine

    International Nuclear Information System (INIS)

    Potten, C.

    2003-01-01

    Epithelial tissues are highly polarised with the proliferative compartment sometimes subdivided into units of proliferation in many instances. My interests have been in trying to understand how many cellular constituents exist, what their function is and intercommunicants are that ensure appropriate steady state cell replacement rates. Radiation has proved to be a valuable tool to induce cell death, reproductive sterilisation, and regenerative proliferation in these systems, the responses to which can provide information on the number of regenerative cells (a function associated with stem cells). Such studies have helped define the epidermal proliferative units and the structurally similar units on the dorsal surface of the tongue. The radiation responses considered in conjunction with a wide range of cell kinetic lineage tracking and somatic mutation studies with complex mathematical modelling, provide insights into the functioning of the poliferative units (crypts) of the small intestine. Comparative studies have then been undertaken with the crypts in the large bowel. In the small intestine, which rarely develops cancer, various protective mechanisms have evolved to ensure the genetic integrity of the stem cell compartment. Stem cells in the small intestinal crypts have an intolerance of genotoxic damage (including that induced by very low doses of radiation), they do not undergo cell cycle arrest and repair but commit an altruistic p53 dependent cell suicide (apoptosis). This process is compromised in the large bowel by bcl-2 expression. Recent studies have suggested a second genome protection mechanism operating in the stem cells of the small intestinal crypts that may also have a p53 dependence. Such studies have allowed the cell lineages and genome protection mechanisms operating in the small intestinal crypts to be defined

  17. Protein kinase D1 (PKD1) influences androgen receptor (AR) function in prostate cancer cells

    International Nuclear Information System (INIS)

    Mak, Paul; Jaggi, Meena; Syed, Viqar; Chauhan, Subhash C.; Hassan, Sazzad; Biswas, Helal; Balaji, K.C.

    2008-01-01

    Protein kinase D1 (PKD1), founding member of PKD protein family, is down-regulated in advanced prostate cancer (PCa). We demonstrate that PKD1 and androgen receptor (AR) are present as a protein complex in PCa cells. PKD1 is associated with a transcriptional complex which contains AR and promoter sequence of the Prostate Specific Antigen (PSA) gene. Ectopic expression of wild type PKD1 and the kinase dead mutant PKD1 (K628W) attenuated the ligand-dependent transcriptional activation of AR in prostate cancer cells and yeast cells indicating that PKD1 can affect AR transcription activity, whereas knocking down PKD1 enhanced the ligand-dependent transcriptional activation of AR. Co-expression of kinase dead mutant with AR significantly inhibited androgen-mediated cell proliferation in both LNCaP and DU145 PC cells. Our data demonstrate for the first time that PKD1 can influence AR function in PCa cells

  18. An endogenous nanomineral chaperones luminal antigen and peptidoglycan to intestinal immune cells.

    Science.gov (United States)

    Powell, Jonathan J; Thomas-McKay, Emma; Thoree, Vinay; Robertson, Jack; Hewitt, Rachel E; Skepper, Jeremy N; Brown, Andy; Hernandez-Garrido, Juan Carlos; Midgley, Paul A; Gomez-Morilla, Inmaculada; Grime, Geoffrey W; Kirkby, Karen J; Mabbott, Neil A; Donaldson, David S; Williams, Ifor R; Rios, Daniel; Girardin, Stephen E; Haas, Carolin T; Bruggraber, Sylvaine F A; Laman, Jon D; Tanriver, Yakup; Lombardi, Giovanna; Lechler, Robert; Thompson, Richard P H; Pele, Laetitia C

    2015-04-01

    In humans and other mammals it is known that calcium and phosphate ions are secreted from the distal small intestine into the lumen. However, why this secretion occurs is unclear. Here, we show that the process leads to the formation of amorphous magnesium-substituted calcium phosphate nanoparticles that trap soluble macromolecules, such as bacterial peptidoglycan and orally fed protein antigens, in the lumen and transport them to immune cells of the intestinal tissue. The macromolecule-containing nanoparticles utilize epithelial M cells to enter Peyer's patches, small areas of the intestine concentrated with particle-scavenging immune cells. In wild-type mice, intestinal immune cells containing these naturally formed nanoparticles expressed the immune tolerance-associated molecule 'programmed death-ligand 1', whereas in NOD1/2 double knockout mice, which cannot recognize peptidoglycan, programmed death-ligand 1 was undetected. Our results explain a role for constitutively formed calcium phosphate nanoparticles in the gut lumen and show how this helps to shape intestinal immune homeostasis.

  19. An endogenous nanomineral chaperones luminal antigen and peptidoglycan to intestinal immune cells

    Science.gov (United States)

    Powell, Jonathan J.; Thomas-McKay, Emma; Thoree, Vinay; Robertson, Jack; Hewitt, Rachel E.; Skepper, Jeremy N.; Brown, Andy; Hernandez-Garrido, Juan Carlos; Midgley, Paul A.; Gomez-Morilla, Inmaculada; Grime, Geoffrey W.; Kirkby, Karen J.; Mabbott, Neil A.; Donaldson, David S.; Williams, Ifor R.; Rios, Daniel; Girardin, Stephen E.; Haas, Carolin T.; Bruggraber, Sylvaine F. A.; Laman, Jon D.; Tanriver, Yakup; Lombardi, Giovanna; Lechler, Robert; Thompson, Richard P. H.; Pele, Laetitia C.

    2015-05-01

    In humans and other mammals it is known that calcium and phosphate ions are secreted from the distal small intestine into the lumen. However, why this secretion occurs is unclear. Here, we show that the process leads to the formation of amorphous magnesium-substituted calcium phosphate nanoparticles that trap soluble macromolecules, such as bacterial peptidoglycan and orally fed protein antigens, in the lumen and transport them to immune cells of the intestinal tissue. The macromolecule-containing nanoparticles utilize epithelial M cells to enter Peyer's patches, small areas of the intestine concentrated with particle-scavenging immune cells. In wild-type mice, intestinal immune cells containing these naturally formed nanoparticles expressed the immune tolerance-associated molecule ‘programmed death-ligand 1’, whereas in NOD1/2 double knockout mice, which cannot recognize peptidoglycan, programmed death-ligand 1 was undetected. Our results explain a role for constitutively formed calcium phosphate nanoparticles in the gut lumen and show how this helps to shape intestinal immune homeostasis.

  20. A20 restricts wnt signaling in intestinal epithelial cells and suppresses colon carcinogenesis.

    Directory of Open Access Journals (Sweden)

    Ling Shao

    Full Text Available Colon carcinogenesis consists of a multistep process during which a series of genetic and epigenetic adaptations occur that lead to malignant transformation. Here, we have studied the role of A20 (also known as TNFAIP3, a ubiquitin-editing enzyme that restricts NFκB and cell death signaling, in intestinal homeostasis and tumorigenesis. We have found that A20 expression is consistently reduced in human colonic adenomas than in normal colonic tissues. To further investigate A20's potential roles in regulating colon carcinogenesis, we have generated mice lacking A20 specifically in intestinal epithelial cells and interbred these with mice harboring a mutation in the adenomatous polyposis coli gene (APC(min. While A20(FL/FL villin-Cre mice exhibit uninflamed intestines without polyps, A20(FL/FL villin-Cre APC(min/+ mice contain far greater numbers and larger colonic polyps than control APC(min mice. We find that A20 binds to the β-catenin destruction complex and restricts canonical wnt signaling by supporting ubiquitination and degradation of β-catenin in intestinal epithelial cells. Moreover, acute deletion of A20 from intestinal epithelial cells in vivo leads to enhanced expression of the β-catenin dependent genes cyclinD1 and c-myc, known promoters of colon cancer. Taken together, these findings demonstrate new roles for A20 in restricting β-catenin signaling and preventing colon tumorigenesis.

  1. Immunohistochemical detection of tyrosine kinase B (TrkB in the enteric nervous system of the small intestine in pigeon (Columba livia

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    A Germanà

    2009-06-01

    Full Text Available The presence and cell localization of TrkB, the main receptor for the neurotrophins (NTs, was investigated immunohistochemically in the small intestine of adult pigeons, with special reference to the enteric nervous system (ENS. Several neuronal (neurofilament proteins and PGP 9.5 and glial cell (S100 protein markers were studied in parallel. TrkB immunoreactivity (TrkB-IR was found to be restricted to immunohistochemically-identified glial cells present in the enteric plexuses, and to Schwann cells forming the perivascular plexus. Also, TrkB-IR was detected in enterochromaffin cells and in unidentified dendritic cells within the gut-associated lymphoid tissue. The present results demonstrate that as for mammals, TrkB in the ENS is restricted to the glial cells. The possible function of the TrkB ligands, however, remains to be established.

  2. Effects of phorbol ester on mitogen-activated protein kinase kinase activity in wild-type and phorbol ester-resistant EL4 thymoma cells.

    Science.gov (United States)

    Gause, K C; Homma, M K; Licciardi, K A; Seger, R; Ahn, N G; Peterson, M J; Krebs, E G; Meier, K E

    1993-08-05

    Phorbol ester-sensitive and -resistant EL4 thymoma cell lines differ in their ability to activate mitogen-activated protein kinase (MAPK) in response to phorbol ester. Treatment of wild-type EL4 cells with phorbol ester results in the rapid activations of MAPK and pp90rsk kinase, a substrate for MAPK, while neither kinase is activated in response to phorbol ester in variant EL4 cells. This study examines the activation of MAPK kinase (MAPKK), an activator of MAPK, in wild-type and variant EL4 cells. Phosphorylation of a 40-kDa substrate, identified as MAPK, was observed following in vitro phosphorylation reactions using cytosolic extracts or Mono Q column fractions prepared from phorbol ester-treated wild-type EL4 cells. MAPKK activity coeluted with a portion of the inactive MAPK upon Mono Q anion-exchange chromatography, permitting detection of the MAPKK activity in fractions containing both kinases. This MAPKK activity was present in phorbol ester-treated wild-type cells, but not in phorbol ester-treated variant cells or in untreated wild-type or variant cells. The MAPKK from wild-type cells was able to activate MAPK prepared from either wild-type or variant cells. MAPKK activity could be stimulated in both wildtype and variant EL4 cells in response to treatment of cells with okadaic acid. These results indicate that the failure of variant EL4 cells to activate MAP kinase in response to phorbol ester is due to a failure to activate MAPKK. Therefore, the step that confers phorbol ester resistance to variant EL4 cells lies between the activation of protein kinase C and the activation of MAPKK.

  3. Synapses of Amphids Defective (SAD-A) Kinase Promotes Glucose-stimulated Insulin Secretion through Activation of p21-activated Kinase (PAK1) in Pancreatic β-Cells*

    Science.gov (United States)

    Nie, Jia; Sun, Chao; Faruque, Omar; Ye, Guangming; Li, Jia; Liang, Qiangrong; Chang, Zhijie; Yang, Wannian; Han, Xiao; Shi, Yuguang

    2012-01-01

    The p21-activated kinase-1 (PAK1) is implicated in regulation of insulin exocytosis as an effector of Rho GTPases. PAK1 is activated by the onset of glucose-stimulated insulin secretion (GSIS) through phosphorylation of Thr-423, a major activation site by Cdc42 and Rac1. However, the kinase(s) that phosphorylates PAK1 at Thr-423 in islet β-cells remains elusive. The present studies identified SAD-A (synapses of amphids defective), a member of AMP-activated protein kinase-related kinases exclusively expressed in brain and pancreas, as a key regulator of GSIS through activation of PAK1. We show that SAD-A directly binds to PAK1 through its kinase domain. The interaction is mediated by the p21-binding domain (PBD) of PAK1 and requires both kinases in an active conformation. The binding leads to direct phosphorylation of PAK1 at Thr-423 by SAD-A, triggering the onset of GSIS from islet β-cells. Consequently, ablation of PAK1 kinase activity or depletion of PAK1 expression completely abolishes the potentiating effect of SAD-A on GSIS. Consistent with its role in regulating GSIS, overexpression of SAD-A in MIN6 islet β-cells significantly stimulated cytoskeletal remodeling, which is required for insulin exocytosis. Together, the present studies identified a critical role of SAD-A in the activation of PAK1 during the onset of insulin exocytosis. PMID:22669945

  4. Synapses of amphids defective (SAD-A) kinase promotes glucose-stimulated insulin secretion through activation of p21-activated kinase (PAK1) in pancreatic β-Cells.

    Science.gov (United States)

    Nie, Jia; Sun, Chao; Faruque, Omar; Ye, Guangming; Li, Jia; Liang, Qiangrong; Chang, Zhijie; Yang, Wannian; Han, Xiao; Shi, Yuguang

    2012-07-27

    The p21-activated kinase-1 (PAK1) is implicated in regulation of insulin exocytosis as an effector of Rho GTPases. PAK1 is activated by the onset of glucose-stimulated insulin secretion (GSIS) through phosphorylation of Thr-423, a major activation site by Cdc42 and Rac1. However, the kinase(s) that phosphorylates PAK1 at Thr-423 in islet β-cells remains elusive. The present studies identified SAD-A (synapses of amphids defective), a member of AMP-activated protein kinase-related kinases exclusively expressed in brain and pancreas, as a key regulator of GSIS through activation of PAK1. We show that SAD-A directly binds to PAK1 through its kinase domain. The interaction is mediated by the p21-binding domain (PBD) of PAK1 and requires both kinases in an active conformation. The binding leads to direct phosphorylation of PAK1 at Thr-423 by SAD-A, triggering the onset of GSIS from islet β-cells. Consequently, ablation of PAK1 kinase activity or depletion of PAK1 expression completely abolishes the potentiating effect of SAD-A on GSIS. Consistent with its role in regulating GSIS, overexpression of SAD-A in MIN6 islet β-cells significantly stimulated cytoskeletal remodeling, which is required for insulin exocytosis. Together, the present studies identified a critical role of SAD-A in the activation of PAK1 during the onset of insulin exocytosis.

  5. Naturally occurring glucagon-like peptide-2 (GLP-2) receptors in human intestinal cell lines.

    Science.gov (United States)

    Sams, Anette; Hastrup, Sven; Andersen, Marie; Thim, Lars

    2006-02-17

    Although clinical trials with GLP-2 receptor agonists are currently ongoing, the mechanisms behind GLP-2-induced intestinal epithelial growth remain to be understood. To approach the GLP-2 mechanism of action this study aimed to identify intestinal cell lines endogenously expressing the GLP-2 receptor. Here we report the first identification of a cell line endogenously expressing functional GLP-2 receptors. The human intestinal epithelial cell line, FHC, expressed GLP-2 receptor encoding mRNA (RT-PCR) and GLP-2 receptor protein (Western blot). In cultured FHC cells, GLP-2 induced concentration dependent cAMP accumulation (pEC(50)=9.7+/-0.04 (mean+/-S.E.M., n=4)). In addition, a naturally occurring human intestinal fibroblast cell line, 18Co, endogenously expressing GLP-2 receptor encoding mRNA (RT-PCR) and protein (Western blot) was identified. No receptor functionality (binding or G-protein signalling) could be demonstrated in 18Co cells. The identified gut-relevant cell lines provide tools for future clarification of the mechanisms underlying GLP-2-induced epithelial growth.

  6. Persistent Transmissible Gastroenteritis Virus Infection Enhances Enterotoxigenic Escherichia coli K88 Adhesion by Promoting Epithelial-Mesenchymal Transition in Intestinal Epithelial Cells.

    Science.gov (United States)

    Xia, Lu; Dai, Lei; Yu, Qinghua; Yang, Qian

    2017-11-01

    Transmissible gastroenteritis virus (TGEV) is a coronavirus characterized by diarrhea and high morbidity rates, and the mortality rate is 100% in piglets less than 2 weeks old. Pigs infected with TGEV often suffer secondary infection by other pathogens, which aggravates the severity of diarrhea, but the mechanisms remain unknown. Here, we hypothesized that persistent TGEV infection stimulates the epithelial-mesenchymal transition (EMT), and thus enterotoxigenic Escherichia coli (ETEC) can more easily adhere to generating cells. Intestinal epithelial cells are the primary targets of TGEV and ETEC infections. We found that TGEV can persistently infect porcine intestinal columnar epithelial cells (IPEC-J2) and cause EMT, consistent with multiple changes in key cell characteristics. Infected cells display fibroblast-like shapes; exhibit increases in levels of mesenchymal markers with a corresponding loss of epithelial markers; have enhanced expression levels of interleukin-1β (IL-1β), IL-6, IL-8, transforming growth factor β (TGF-β), and tumor necrosis factor alpha (TNF-α) mRNAs; and demonstrate increases in migratory and invasive behaviors. Additional experiments showed that the activation of the phosphatidylinositol 3-kinase (PI3K)/Akt and extracellular signal-regulated kinase (ERK) signaling pathways via TGF-β is critical for the TGEV-mediated EMT process. Cellular uptake is also modified in cells that have undergone EMT. TGEV-infected cells have higher levels of integrin α5 and fibronectin and exhibit enhanced ETEC K88 adhesion. Reversal of EMT reduces ETEC K88 adhesion and inhibits the expression of integrin α5 and fibronectin. Overall, these results suggest that TGEV infection induces EMT in IPEC-J2 cells, increasing the adhesion of ETEC K88 in the intestine and facilitating dual infection. IMPORTANCE Transmissible gastroenteritis virus (TGEV) causes pig diarrhea and is often followed by secondary infection by other pathogens. In this study, we showed

  7. Mechanistic studies of a cell-permeant peptide designed to enhance myosin light chain phosphorylation in polarized intestinal epithelia.

    Science.gov (United States)

    Almansour, Khaled; Taverner, Alistair; Eggleston, Ian M; Mrsny, Randall J

    2018-06-10

    Tight junction (TJ) structures restrict the movement of solutes between adjacent epithelial cells to maintain homeostatic conditions. A peptide, termed PIP 640, with the capacity to regulate the transient opening of intestinal TJ structures through an endogenous mechanism involving the induction of myosin light chain (MLC) phosphorylation at serine 19 (MLC-pS 19 ) has provided a promising new method to enhance the in vivo oral bioavailability of peptide therapeutics. PIP 640 is a decapeptide composed of all D-amino acids (rrdykvevrr-NH 2 ) that contains a central sequence designed to emulates a specific domain of C-kinase potentiated protein phosphatase-1 inhibitor-17 kDa (CPI-17) surrounded by positively-charged amino acids that provide a cell penetrating peptide (CPP)-like character. Here, we examine compositional requirements of PIP 640 with regard to its actions on MLC phosphorylation, its intracellular localization to TJ structures, and its interactions with MLC phosphatase (MLCP) elements that correlate with enhanced solute uptake. These studies showed that a glutamic acid and tyrosine within this peptide are critical for PIP 640 to retain its ability to increase MLC-pS 19 levels and enhance the permeability of macromolecular solutes of the size range of therapeutic peptides without detectable cytotoxicity. On the other hand, exchange of the aspartic acid for alanine and then arginine resulted in an increasingly greater bias toward protein phosphatase-1 (PP1) relative to MLCP inhibition, an outcome that resulted in increased paracellular permeability for solutes in the size range of therapeutic peptides, but with a significant increase in cytotoxicity. Together, these data further our understanding of the composition requirements of PIP 640 with respect to the desired goal of transiently altering the intestinal epithelial cell paracellular barrier properties through an endogenous mechanism, providing a novel approach to enhance the oral bioavailability of

  8. Sucralfate prevents the delay of wound repair in intestinal epithelial cells by hydrogen peroxide through NF-kappaB pathway.

    Science.gov (United States)

    Shindo, Kenichi; Iizuka, Masahiro; Sasaki, Kenji; Konno, Shiho; Itou, Hiroaki; Horie, Yasuo; Watanabe, Sumio

    2006-05-01

    Recent studies have shown that sucralfate (SF) has therapeutic effects on colonic inflammation in ulcerative colitis. The aim of this study was to clarify the function of SF for wound repair in intestinal epithelial cells (IEC). (1) Activation of signal proteins [ERK1/2 mitogen-activated protein kinase (MAPK), IkappaB-alpha] in IEC-6 cells after stimulation with 10(-4) M potassium sucrose octasulfate (SOS), which is the functional element of SF, was assessed by Western blot. (2) Induction of transforming growth factor (TGF)-beta1, TGF-alpha, EGF, and cyclooxygenase-2 (COX-2) mRNA after stimulation of IEC-6 cells with SOS was assessed by reverse transcriptase-polymerase chain reaction. (3) IEC-6 cells were wounded and cultured for 24 h with various concentrations of SOS in the absence or presence of 20 microM H(2)O(2). Epithelial migration or proliferation was assessed by counting migrating cells or bromodeoxyuridine (BrdU)-positive cells across the wound border. (1) SOS activated IkappaB-alpha, but it did not activate ERK1/2 MAPK. (2) SOS enhanced the expression of COX-2 mRNA, but it did not change the mRNA expression of other growth factors. (3) SOS did not enhance wound repair in IEC-6 cells, but it decreased the number of dead cells (maximum, 74%) (P < 0.01) in a dose-dependent manner and prevented the diminishment of epithelial migration (maximum, 61%) (P < 0.01) and proliferation (maximum, 37%) (P < 0.05) induced by H(2)O(2). These functions of SOS were suppressed by the NF-kappaB and COX-2 inhibitors. SOS prevented the delay of wound repair in IEC-6 cells induced by H(2)O(2), probably through induction of COX-2 and an anti-apoptotic mechanism. These effects of SOS might be given through the activation of the NF-kappaB pathway.

  9. Bile acid receptor TGR5 overexpression is associated with decreased intestinal mucosal injury and epithelial cell proliferation in obstructive jaundice.

    Science.gov (United States)

    Ji, Chen-Guang; Xie, Xiao-Li; Yin, Jie; Qi, Wei; Chen, Lei; Bai, Yun; Wang, Na; Zhao, Dong-Qiang; Jiang, Xiao-Yu; Jiang, Hui-Qing

    2017-04-01

    Bile acids stimulate intestinal epithelial proliferation in vitro. We sought to investigate the role of the bile acid receptor TGR5 in the protection of intestinal epithelial proliferation in obstructive jaundice. Intestinal tissues and serum samples were obtained from patients with malignant obstructive jaundice and from bile duct ligation (BDL) rats. Intestinal permeability and morphological changes in the intestinal mucosa were observed. The functions of TGR5 in cell proliferation in intestinal epithelial injury were determined by overexpression or knockdown studies in Caco-2 and FHs 74 Int cells pretreated with lipopolysaccharide (LPS). Internal biliary drainage was superior to external biliary drainage in recovering intestinal permeability and mucosal histology in patients with obstructive jaundice. In BDL rats, feeding of chenodeoxycholic acid (CDCA) decreased intestinal mucosa injury. The levels of PCNA, a marker of proliferation, increased in response to CDCA feeding and were paralleled by elevated TGR5 expression. CDCA upregulated TGR5 expression and promoted proliferation in Caco-2 and FHs 74 Int cells pretreated with LPS. Overexpression of TGR5 resulted in increased PCNA, cell viability, EdU incorporation, and the proportion of cells in S phase, whereas knockdown of TGR5 had the opposite effect. Our data indicate that bile acids promote intestinal epithelial cell proliferation and decrease mucosal injury by upregulating TGR5 expression in obstructive jaundice. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Csk Homologous Kinase, a Potential Regulator of CXCR4-Medicated Breast Cancer Cell Metastasis

    Science.gov (United States)

    2011-08-01

    is a non-receptor tyrosine kinase and a second member of the Csk family. Like Csk, CHK has Src homology 2 ( SH2 ) and SH3 domains and lacks the...MSCV-retroviral vectors encoding either wild-type CHK or kinase -dead CHK or wild type SH2 domain or SH2 -R147A or SH2 -G129A. All these constructs were... Kinase , a Potential Regulator of CXCR4-Medicated Breast Cancer Cell Metastasis Byeong-Chel Lee The University of Pittsburgh Pittsburgh, PA 15213

  11. Campylobacter jejuni induces transcytosis of commensal bacteria across the intestinal epithelium through M-like cells

    Science.gov (United States)

    2010-01-01

    Background Recent epidemiological analyses have implicated acute Campylobacter enteritis as a factor that may incite or exacerbate inflammatory bowel disease (IBD) in susceptible individuals. We have demonstrated previously that C. jejuni disrupts the intestinal barrier function by rapidly inducing epithelial translocation of non-invasive commensal bacteria via a transcellular lipid raft-mediated mechanism ('transcytosis'). To further characterize this mechanism, the aim of this current study was to elucidate whether C. jejuni utilizes M cells to facilitate transcytosis of commensal intestinal bacteria. Results C. jejuni induced translocation of non-invasive E. coli across confluent Caco-2 epithelial monolayers in the absence of disrupted transepithelial electrical resistance or increased permeability to a 3 kDa dextran probe. C. jejuni-infected monolayers displayed increased numbers of cells expressing the M cell-specific marker, galectin-9, reduced numbers of enterocytes that stained with the absorptive enterocyte marker, Ulex europaeus agglutinin-1, and reduced activities of enzymes typically associated with absorptive enterocytes (namely alkaline phosphatase, lactase, and sucrase). Furthermore, in Campylobacter-infected monolayers, E. coli were observed to be internalized specifically within epithelial cells displaying M-like cell characteristics. Conclusion These data indicate that C. jejuni may utilize M cells to promote transcytosis of non-invasive bacteria across the intact intestinal epithelial barrier. This mechanism may contribute to the inflammatory immune responses against commensal intestinal bacteria commonly observed in IBD patients. PMID:21040540

  12. Campylobacter jejuni induces transcytosis of commensal bacteria across the intestinal epithelium through M-like cells

    Directory of Open Access Journals (Sweden)

    Kalischuk Lisa D

    2010-11-01

    Full Text Available Abstract Background Recent epidemiological analyses have implicated acute Campylobacter enteritis as a factor that may incite or exacerbate inflammatory bowel disease (IBD in susceptible individuals. We have demonstrated previously that C. jejuni disrupts the intestinal barrier function by rapidly inducing epithelial translocation of non-invasive commensal bacteria via a transcellular lipid raft-mediated mechanism ('transcytosis'. To further characterize this mechanism, the aim of this current study was to elucidate whether C. jejuni utilizes M cells to facilitate transcytosis of commensal intestinal bacteria. Results C. jejuni induced translocation of non-invasive E. coli across confluent Caco-2 epithelial monolayers in the absence of disrupted transepithelial electrical resistance or increased permeability to a 3 kDa dextran probe. C. jejuni-infected monolayers displayed increased numbers of cells expressing the M cell-specific marker, galectin-9, reduced numbers of enterocytes that stained with the absorptive enterocyte marker, Ulex europaeus agglutinin-1, and reduced activities of enzymes typically associated with absorptive enterocytes (namely alkaline phosphatase, lactase, and sucrase. Furthermore, in Campylobacter-infected monolayers, E. coli were observed to be internalized specifically within epithelial cells displaying M-like cell characteristics. Conclusion These data indicate that C. jejuni may utilize M cells to promote transcytosis of non-invasive bacteria across the intact intestinal epithelial barrier. This mechanism may contribute to the inflammatory immune responses against commensal intestinal bacteria commonly observed in IBD patients.

  13. Developmental changes in intraepithelial T lymphocytes and NK cells in the small intestine of neonatal rats.

    Science.gov (United States)

    Pérez-Cano, Francisco J; Castellote, Cristina; González-Castro, Ana M; Pelegrí, Carme; Castell, Margarida; Franch, Angels

    2005-11-01

    The main objective of this study was to characterize developmental changes in small intestinal intraepithelial lymphocyte (IEL) subpopulations during the suckling period, thus contributing to the understanding of the development of diffuse gut-associated lymphoid tissue (GALT) and to the identification of early mechanisms that protect the neonate from the first contact with diet and gut microbial antigens. The study was performed by double labeling and flow cytometry in IEL isolated from the proximal and distal small intestine of 1- to 21-d-old Lewis rats. During the suckling period, intraepithelial natural killer (NK) cells changed from a typical systemic phenotype, CD8+, to a specific intestinal phenotype, CD8-. Analysis of CD8+ IEL revealed a progressive increase in the relative number of CD8+ IEL co-expressing TCRalphabeta, cells associated with acquired immunity, whereas the percentage of CD8+ cells expressing the NK receptor, i.e. cells committed to innate immunity, decreased. At weaning, IEL maturity was still not achieved, as revealed by a phenotypic pattern that differed from that of adult rats. Thus, late after weaning, the regulatory CD8+CD4+ T IEL population appeared and the NK population declined. In summary, the intestinal intraepithelial compartment undergoes changes in its lymphocyte composition associated with the first ingestion of food. These changes are focused on a relatively high proportion of NK cells during the suckling period, and after weaning, an expansion of the regulatory CD8+CD4+ T cells.

  14. Chitosan-modified porous silicon microparticles for enhanced permeability of insulin across intestinal cell monolayers.

    Science.gov (United States)

    Shrestha, Neha; Shahbazi, Mohammad-Ali; Araújo, Francisca; Zhang, Hongbo; Mäkilä, Ermei M; Kauppila, Jussi; Sarmento, Bruno; Salonen, Jarno J; Hirvonen, Jouni T; Santos, Hélder A

    2014-08-01

    Porous silicon (PSi) based particulate systems are emerging as an important drug delivery system due to its advantageous properties such as biocompatibility, biodegradability and ability to tailor the particles' physicochemical properties. Here, annealed thermally hydrocarbonized PSi (AnnTHCPSi) and undecylenic acid modified AnnTHCPSi (AnnUnTHCPSi) microparticles were developed as a PSi-based platform for oral delivery of insulin. Chitosan (CS) was used to modify the AnnUnTHCPSi microparticles to enhance the intestinal permeation of insulin. Surface modification with CS led to significant increase in the interaction of PSi microparticles with Caco-2/HT-29 cell co-culture monolayers. Compared to pure insulin, the CS-conjugated microparticles significantly improved the permeation of insulin across the Caco-2/HT-29 cell monolayers, with ca. 20-fold increase in the amount of insulin permeated and ca. 7-fold increase in the apparent permeability (P(app)) value. Moreover, among all the investigated particles, the CS-conjugated microparticles also showed the highest amount of insulin associated with the mucus layer and the intestinal Caco-2 cells and mucus secreting HT-29 cells. Our results demonstrate that CS-conjugated AnnUnTHCPSi microparticles can efficiently enhance the insulin absorption across intestinal cells, and thus, they are promising microsystems for the oral delivery of proteins and peptides across the intestinal cell membrane. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. STK33 kinase inhibitor BRD-8899 has no effect on KRAS-dependent cancer cell viability.

    Science.gov (United States)

    Luo, Tuoping; Masson, Kristina; Jaffe, Jacob D; Silkworth, Whitney; Ross, Nathan T; Scherer, Christina A; Scholl, Claudia; Fröhling, Stefan; Carr, Steven A; Stern, Andrew M; Schreiber, Stuart L; Golub, Todd R

    2012-02-21

    Approximately 30% of human cancers harbor oncogenic gain-of-function mutations in KRAS. Despite interest in KRAS as a therapeutic target, direct blockade of KRAS function with small molecules has yet to be demonstrated. Based on experiments that lower mRNA levels of protein kinases, KRAS-dependent cancer cells were proposed to have a unique requirement for the serine/threonine kinase STK33. Thus, it was suggested that small-molecule inhibitors of STK33 might have therapeutic benefit in these cancers. Here, we describe the development of selective, low nanomolar inhibitors of STK33's kinase activity. The most potent and selective of these, BRD8899, failed to kill KRAS-dependent cells. While several explanations for this result exist, our data are most consistent with the view that inhibition of STK33's kinase activity does not represent a promising anti-KRAS therapeutic strategy.

  16. Bacillus subtilis and yeast cell wall improve the intestinal health of broilers challenged by Clostridium perfringens.

    Science.gov (United States)

    Li, Z; Wang, W; Lv, Z; Liu, D; Guo, Y

    2017-12-01

    1. The objective was to investigate the effects of Bacillus subtilis, yeast cell wall (YCW) and their combination on intestinal health of broilers challenged by Clostridium perfringens over a 21-d period. 2. Using a 5 × 2 factorial arrangement of treatments, 800 1-d-old male Cobb 500 broilers were used to study the effects of feed additives (without additive or with zinc bacitracin, B. subtilis, YCW, and the combination of B. subtilis and YCW), pathogen challenge (without or with Clostridium perfringens challenge), and their interactive effects. 3. C. perfringens infection increased intestinal lesions scores, damaged intestinal histomorphology, increased serum endotoxin concentration, cytokine mRNA expression and intestinal population of C. perfringens and Escherichia coli and decreased ileal bifidobacteria numbers. The 4 additives decreased serum endotoxin. Zinc bacitracin tended to decrease cytokine mRNA expression and the intestinal number of C. perfringens and E. coli. B. subtilis, YCW and their combination increased cytokine mRNA expression. B. subtilis and YCW decreased the number of C. perfringens and E. coli in the ileum, and their combination decreased pathogens numbers in the ileum and caecum. 4. In conclusion, B. subtilis, YCW and their combination improved the intestinal health of NE-infected broilers, and could be potential alternatives to antibiotics.

  17. Primary intestinal T cell lymphomas in Indian patients - In search of enteropathic T cell lymphoma

    Directory of Open Access Journals (Sweden)

    Shet Tanuja

    2010-07-01

    Full Text Available Objective: This series of six intestinal T cell lymphomas (ITCL attempts to document enteropathy-associated T cell lymphoma (EATCL in India. Materials and Methods: A total of six ITCL were selected from 170 gastrointestinal lymphomas in last 10 years. Results: The cases studied included EATCL (4, ITCL with a CD4 positive phenotype (1 and ITCL NK/T cell type (1. Of the four EATCL, two occurred in the ileum, one in right colon and one in duodenum. In three EATCL cases, there was history of celiac disease or lactose intolerance and enteropathic changes were noted in the adjacent mucosa. These tumors had CD3+/CD8+/CD56 (+/-/CD4-/ Granzyme B+ immunophenotype. One EATCL was monomorphic small cell type (type II EATCL with a CD3+/CD8-CD56+/CD4-/ Granzyme B+ phenotype. EBER- ISH (Epstein Barr virus coded RNA′s- in situ hybridization revealed positive tumor cells in ITCL NK/T cell type and in bystander cells in three EATCL. Conclusion: ITCL are rare in Indian patients but do occur and comprise a mixture of the enteropathic and non-enteropathic subtypes.

  18. Luteolin suppresses cancer cell proliferation by targeting vaccinia-related kinase 1.

    Directory of Open Access Journals (Sweden)

    Ye Seul Kim

    Full Text Available Uncontrolled proliferation, a major feature of cancer cells, is often triggered by the malfunction of cell cycle regulators such as protein kinases. Recently, cell cycle-related protein kinases have become attractive targets for anti-cancer therapy, because they play fundamental roles in cellular proliferation. However, the protein kinase-targeted drugs that have been developed so far do not show impressive clinical results and also display severe side effects; therefore, there is undoubtedly a need to investigate new drugs targeting other protein kinases that are critical in cell cycle progression. Vaccinia-related kinase 1 (VRK1 is a mitotic kinase that functions in cell cycle regulation by phosphorylating cell cycle-related substrates such as barrier-to-autointegration factor (BAF, histone H3, and the cAMP response element (CRE-binding protein (CREB. In our study, we identified luteolin as the inhibitor of VRK1 by screening a small-molecule natural compound library. Here, we evaluated the efficacy of luteolin as a VRK1-targeted inhibitor for developing an effective anti-cancer strategy. We confirmed that luteolin significantly reduces VRK1-mediated phosphorylation of the cell cycle-related substrates BAF and histone H3, and directly interacts with the catalytic domain of VRK1. In addition, luteolin regulates cell cycle progression by modulating VRK1 activity, leading to the suppression of cancer cell proliferation and the induction of apoptosis. Therefore, our study suggests that luteolin-induced VRK1 inhibition may contribute to establish a novel cell cycle-targeted strategy for anti-cancer therapy.

  19. Reduction of Fibrogenesis by Selective Delivery of a Rho Kinase Inhibitor to Hepatic Stellate Cells in Mice

    NARCIS (Netherlands)

    van Beuge, M. M.; Prakash, J.; Lacombe, M.; Gosens, R.; Post, E.; Reker-Smit, C.; Beljaars, L.; Poelstra, K.

    One of the pathways activated during liver fibrosis is the Rho kinase pathway, which regulates activation, migration, and contraction of hepatic stellate cells (HSC). Inhibition of this kinase by the Rho kinase inhibitor Y27632 [(+)-(R)-trans-4-(1-aminoethyl)-N-(4-pyridyl)cyclohexanecarboxamide

  20. Lactoferrin targets T cells in the small intestine

    DEFF Research Database (Denmark)

    Nielsen, Sanne Mie; Hansen, Gert Helge; Danielsen, E Michael

    2010-01-01

    BACKGROUND: Lactoferrin (Lf) belongs to the transferrin family of non-heme iron-binding proteins and is found in milk and mucosal secretions. Consequently, it is now considered a multifunctional protein mainly involved in both the innate and adaptive immune defenses of the organism against various...... explants of pig small intestine by immunofluorescence and immunogold microscopy. RESULTS: Lf rapidly bound to the brush border and subsequently appeared in punctae in the apical cytoplasm, indicating internalization into an endosomal compartment. Essentially, no labeling was detected elsewhere...

  1. Efficacy of ponatinib against ABL tyrosine kinase inhibitor-resistant leukemia cells

    International Nuclear Information System (INIS)

    Okabe, Seiichi; Tauchi, Tetsuzo; Tanaka, Yuko; Ohyashiki, Kazuma

    2013-01-01

    Highlights: •Efficacy of ponatinib against ABL tyrosine kinase inhibitor-resistant leukemia cells okabe et al. •Imatinib or nilotinib resistance was involved Src family kinase. •The BCR-ABL point mutation (E334V) was highly resistant to imatinib or nilotinib. •Ponatinib was a powerful strategy against imatinib or nilotinib resistant Ph-positive cells. -- Abstract: Because a substantial number of patients with chronic myeloid leukemia acquire resistance to ABL tyrosine kinase inhibitors (TKIs), their management remains a challenge. Ponatinib, also known as AP24534, is an oral multi-targeted TKI. Ponatinib is currently being investigated in a pivotal phase 2 clinical trial. In the present study, we analyzed the molecular and functional consequences of ponatinib against imatinib- or nilotinib-resistant (R) K562 and Ba/F3 cells. The proliferation of imatinib- or nilotinib-resistant K562 cells did not decrease after treatment with imatinib or nilotinib. Src family kinase Lyn was activated. Point mutation Ba/F3 cells (E334 V) were also highly resistant to imatinib and nilotinib. Treatment with ponatinib for 72 h inhibited the growth of imatinib- and nilotinib-resistant cells. The phosphorylation of BCR-ABL, Lyn, and Crk-L was reduced. This study demonstrates that ponatinib has an anti-leukemia effect by reducing ABL and Lyn kinase activity and this information may be of therapeutic relevance

  2. Inhibition of protein kinase C induces differentiation in Neuro-2a cells

    International Nuclear Information System (INIS)

    Minana, M.D.; Felipo, V.; Grisolia, S.

    1990-01-01

    1-(5-Isoquinolinylsulfonyl)-2-methylpiperazine (H7), a potent inhibitor of protein kinase C, induced neuritogenesis in Neuro-2a cells, whereas N-(2-guanidinoethyl)-5-isoquinolinesulfonamide (HA 1004), which inhibits more efficiently cAMP- and cGMP-dependent protein kinases, did not. The effect, noticeable after 3 hr, was maximum (13-fold increase at 500 μM H7) between 1 and 3 days and was maintained over 2 months. In controls, 90% of the cells were undifferentiated, whereas after 3 hr with 500 μM H7 only 25% of the cells remained undifferentiated. DNA synthesis decreased as the number of differentiated cells increased. Differentiation is also functional since acetylcholinesterase activity increased ∼7-fold after 48 hr with 500 μM H7. Phorbol 12-myristate 13-acetate, a specific activator of protein kinase C, prevented or reversed the induction of neuritogenesis and the inhibition of DNA synthesis by H7. There is a good correlation between the level of protein kinase C and the percentage of differentiated cells. The results indicate that protein kinase C may play a key role in the control of differentiation of neural cells. Some possible clinical implications are briefly discussed

  3. Efficacy of ponatinib against ABL tyrosine kinase inhibitor-resistant leukemia cells

    Energy Technology Data Exchange (ETDEWEB)

    Okabe, Seiichi, E-mail: okabe@tokyo-med.ac.jp; Tauchi, Tetsuzo; Tanaka, Yuko; Ohyashiki, Kazuma

    2013-06-07

    Highlights: •Efficacy of ponatinib against ABL tyrosine kinase inhibitor-resistant leukemia cells okabe et al. •Imatinib or nilotinib resistance was involved Src family kinase. •The BCR-ABL point mutation (E334V) was highly resistant to imatinib or nilotinib. •Ponatinib was a powerful strategy against imatinib or nilotinib resistant Ph-positive cells. -- Abstract: Because a substantial number of patients with chronic myeloid leukemia acquire resistance to ABL tyrosine kinase inhibitors (TKIs), their management remains a challenge. Ponatinib, also known as AP24534, is an oral multi-targeted TKI. Ponatinib is currently being investigated in a pivotal phase 2 clinical trial. In the present study, we analyzed the molecular and functional consequences of ponatinib against imatinib- or nilotinib-resistant (R) K562 and Ba/F3 cells. The proliferation of imatinib- or nilotinib-resistant K562 cells did not decrease after treatment with imatinib or nilotinib. Src family kinase Lyn was activated. Point mutation Ba/F3 cells (E334 V) were also highly resistant to imatinib and nilotinib. Treatment with ponatinib for 72 h inhibited the growth of imatinib- and nilotinib-resistant cells. The phosphorylation of BCR-ABL, Lyn, and Crk-L was reduced. This study demonstrates that ponatinib has an anti-leukemia effect by reducing ABL and Lyn kinase activity and this information may be of therapeutic relevance.

  4. Paraneoplastic hypereosinophilia in a dog with intestinal T-cell lymphoma.

    Science.gov (United States)

    Marchetti, Veronica; Benetti, Cecilia; Citi, Simona; Taccini, Valentina

    2005-09-01

    A 9-year-old, intact male Doberman Pinscher was examined because of anorexia and weakness. Results of a CBC showed severe, microcytic, hypochromic anemia with mild eosinophilia (2944 cells/microL, reference interval 100-1250/microL) and thrombocytosis. Hypoferremia, hypoferritinemia, and a positive fecal occult blood test supported a diagnosis of iron deficiency anemia secondary to chronic intestinal hemorrhage. Abdominal ultrasound evaluation showed a thickened small intestinal loop, of which representative specimens were obtained during exploratory laparotomy. Histologically, the intestinal wall was infiltrated by a neoplastic population of large, round, lymphoid cells with vesicular chromatin, 1 or more prominent nucleoli, and a high number of mitotic figures. The cells were closely admixed with mature eosinophils, but were negative for metachromatic granules with toluidine blue. Immunohistochemically, tumor cells were positive for CD3, and negative for CD21, Pan B, and CD79a. A diagnosis of intestinal T-cell lymphoma was made. Chemotherapy was begun, with 30 mg/m;2 of doxorubicin administered intravenously every 3 weeks. Eosinophil concentration was 880/microL 2 weeks after surgery (on day 15 after presentation) but increased markedly to 62,914/microL on day 30, 62,400/microL on day 37, and 39,444/microL on day 58 after presentation. An association between hypereosinophilia and T-cell lymphoma is well established in human patients, in whom production of IL-5 by neoplastic T cells has been demonstrated. Hypereosinophilia has been reported only rarely with intestinal lymphoma in cats and horses, and with T-cell lymphoma in dogs.

  5. Culturing human intestinal stem cells for regenerative applications in the treatment of inflammatory bowel disease

    DEFF Research Database (Denmark)

    Holmberg, Fredrik Eo; Seidelin, Jakob B; Yin, Xiaolei

    2017-01-01

    models suggests that intestinal stem cell transplantation could constitute a novel treatment strategy to re-establish mucosal barrier function in patients with severe disease. Intestinal stem cells can be grownin vitroin organoid structures, though only a fraction of the cells contained are stem cells...... with regenerative capabilities. Hence, techniques to enrich stem cell populations are being pursued through the development of multiple two-dimensional and three-dimensional culture protocols, as well as co-culture techniques and multiple growth medium compositions. Moreover, research in support matrices allowing...... for efficient clinical application is in progress.In vitroculture is accomplished by modulating the signaling pathways fundamental for the stem cell niche with a suitable culture matrix to provide additional contact-dependent stimuli and structural support. The aim of this review was to discuss medium...

  6. Ultrastructure of interstitial cells of Cajal associated with deep muscular plexus of human small intestine

    DEFF Research Database (Denmark)

    Rumessen, J J; Mikkelsen, H B; Thuneberg, L

    1992-01-01

    Evidence showing that interstitial cells of Cajal have important regulatory functions in the gut musculature is accumulating. In the current study, the ultrastructure of the deep muscular plexus and associated interstial cells of Cajal in human small intestine were studied to provide a reference...... a continuous basal lamina, caveolae, intermediate filaments, dense bodies, dense bands, and a well-developed subsurface smooth endoplasmic reticulum), but the arrangement of organelles was clearly different, and cisternae of granular endoplasmic reticulum were abundant. Interstitial cells of Cajal were......, and only few gap junctions with other interstitial cells of Cajal or with the musculature were observed. Compared with interstitial cells of Cajal from other mammals, those associated with the deep muscular plexus in the human small intestine more closely resemble smooth muscle cells...

  7. Development of microfluidic cell culture devices towards an in vitro human intestinal barrier model

    DEFF Research Database (Denmark)

    Tan, Hsih-Yin

    to enable real-time detection of cell responses, adjustment of cellular stimulation etc. leading to establishment of conditional experiments. In this project, microfluidic systems engineering was leveraged to develop an eight chamber multi-layer microchip for intestinal barrier studies. Sandwiched between...... the layers was a modified Teflon porous membrane for cell culture. The novelty lies in modifying the surface of the porous Teflon support membrane using thiol-ene ‘click’ chemistry, thus allowing the modified Teflon membrane to be bonded between the chip layers to form an enclosed microchip. Successful...... application of the multi-layer microchip was demonstrated by integrating the microchip to an existing cell culture fluidic system to culture the human intestinal epithelial cells, Caco-2, for long term studies. Under the continuous low flow conditions, the cells differentiated into columnar cells displaying...

  8. Nucleoporin 62 and Ca(2+)/calmodulin dependent kinase kinase 2 regulate androgen receptor activity in castrate resistant prostate cancer cells.

    Science.gov (United States)

    Karacosta, Loukia G; Kuroski, Laura A; Hofmann, Wilma A; Azabdaftari, Gissou; Mastri, Michalis; Gocher, Angela M; Dai, Shuhang; Hoste, Allen J; Edelman, Arthur M

    2016-02-15

    Re-activation of the transcriptional activity of the androgen receptor (AR) is an important factor mediating progression from androgen-responsive to castrate-resistant prostate cancer (CRPC). However, the mechanisms regulating AR activity in CRPC remain incompletely understood. Ca(2+) /calmodulin-dependent kinase kinase (CaMKK) 2 was previously shown to regulate AR activity in androgen-responsive prostate cancer cells. Our objective was to further explore the basis of this regulation in CRPC cells. The abundance of CaMKK2 in nuclear fractions of androgen-responsive prostate cancer and CRPC, cells were determined by subcellular fractionation and Western blotting. CaMKK2 association with nuclear pore complexes (NPCs) and nucleoporins (Nups) including Nup62, were imaged by structured illumination and super-resolution fluorescence microscopy and co-immunoprecipitation, respectively. The abundance and subcellular localization of CaMKK2 and Nup62 in human clinical specimens of prostate cancer was visualized by immunohistochemistry. The role of Nups in the growth and viability of CRPC cells was assessed by RNA interference and cell counting. The involvement of CaMKK2 and Nup62 in regulating AR transcriptional activity was addressed by RNA interference, chromatin immunoprecipitation, androgen response element reporter assay, and Western blotting. CaMKK2 was expressed at higher levels in the nuclear fraction of CPRC C4-2 cells, than in that of androgen-responsive LNCaP cells. In C4-2 cells, CaMKK2 associated with NPCs of the nuclear envelope and physically interacted with Nup62. CaMKK2 and Nup62 demonstrated pronounced, and similar increases in both expression and perinuclear/nuclear localization in human clinical specimens of advanced prostate cancer relative to normal prostate. Knockdown of Nup62, but not of Nups, 98 or 88, reduced growth and viability of C4-2 cells. Knockdown of Nup62 produced a greater reduction of the growth and viability of C4-2 cells than of non

  9. Translocation of differently sized and charged polystyrene nanoparticles in in vitro intestinal cell models of increasing complexity

    NARCIS (Netherlands)

    Walczak, A.P.; Kramer, E.; Hendriksen, P.J.M.; Tromp, P.; Helsper, J.P.F.G.; Zande, M. van der; Rietjens, I.M.C.M.; Bouwmeester, H.

    2015-01-01

    Intestinal translocation is a key factor for determining bioavailability of nanoparticles (NPs) after oral uptake. Therefore, we evaluated three in vitro intestinal cell models of increasing complexity which might affect the translocation of NPs: a mono-culture (Caco-2 cells), a co-culture with

  10. Microbiota promote secretory cell determination in the intestinal epithelium by modulating host Notch signaling.

    Science.gov (United States)

    Troll, Joshua V; Hamilton, M Kristina; Abel, Melissa L; Ganz, Julia; Bates, Jennifer M; Stephens, W Zac; Melancon, Ellie; van der Vaart, Michiel; Meijer, Annemarie H; Distel, Martin; Eisen, Judith S; Guillemin, Karen

    2018-02-23

    Resident microbes promote many aspects of host development, although the mechanisms by which microbiota influence host tissues remain unclear. We showed previously that the microbiota is required for allocation of appropriate numbers of secretory cells in the zebrafish intestinal epithelium. Because Notch signaling is crucial for secretory fate determination, we conducted epistasis experiments to establish whether the microbiota modulates host Notch signaling. We also investigated whether innate immune signaling transduces microbiota cues via the Myd88 adaptor protein. We provide the first evidence that microbiota-induced, Myd88-dependent signaling inhibits host Notch signaling in the intestinal epithelium, thereby promoting secretory cell fate determination. These results connect microbiota activity via innate immune signaling to the Notch pathway, which also plays crucial roles in intestinal homeostasis throughout life and when impaired can result in chronic inflammation and cancer. © 2018. Published by The Company of Biologists Ltd.

  11. Dissection of Protein Kinase Pathways in Live Cells Using Photoluminescent Probes: Surveillance or Interrogation?

    Directory of Open Access Journals (Sweden)

    Darja Lavogina

    2018-04-01

    Full Text Available Protein kinases catalyze phosphorylation, a small yet crucial modification that affects participation of the substrate proteins in the intracellular signaling pathways. The activity of 538 protein kinases encoded in human genome relies upon spatiotemporally controlled mechanisms, ensuring correct progression of virtually all physiological processes on the cellular level—from cell division to cell death. The aberrant functioning of protein kinases is linked to a wide spectrum of major health issues including cancer, cardiovascular diseases, neurodegenerative diseases, inflammatory diseases, etc. Hence, significant effort of scientific community has been dedicated to the dissection of protein kinase pathways in their natural milieu. The combination of recent advances in the field of light microscopy, the wide variety of genetically encoded or synthetic photoluminescent scaffolds, and the techniques for intracellular delivery of cargoes has enabled design of a plethora of probes that can report activation of target protein kinases in human live cells. The question remains: how much do we bias intracellular signaling of protein kinases by monitoring it? This review seeks answers to this question by analyzing different classes of probes according to their general structure, mechanism of recognition of biological target, and optical properties necessary for the reporting of intracellular events.

  12. Porcine intestinal mast cells. Evaluation of different fixatives for histochemical staining techniques considering tissue shrinkage

    Directory of Open Access Journals (Sweden)

    J. Rieger

    2013-07-01

    Full Text Available Staining of mast cells (MCs, including porcine ones, is critically dependent upon the fixation and staining technique. In the pig, mucosal and submucosal MCs do not stain or stain only faintly after formalin fixation. Some fixation methods are particularly recommended for MC staining, for example the fixation with Carnoy or lead salts. Zinc salt fixation (ZSF has been reported to work excellently for the preservation of fixation-sensitive antigens. The aim of this study was to establish a reliable histological method for counting of MCs in the porcine intestinum. For this purpose, different tissue fixation and staining methods that also allow potential subsequent immunohistochemical investigations were evaluated in the porcine mucosa, as well as submucosa of small and large intestine. Tissues were fixed in Carnoy, lead acetate, lead nitrate, Zamboni and ZSF and stained subsequently with either polychromatic methylene blue, alcian blue or toluidine blue. For the first time our study reveals that ZSF, a heavy metal fixative, preserves metachromatic staining of porcine MCs. Zamboni fixation was not suitable for histochemical visualization of MCs in the pig intestine. All other tested fixatives were suitable. Alcian blue and toluidine blue co-stained intestinal goblet cells which made a prima facie identification of MCs difficult. The polychromatic methylene blue proved to be the optimal staining. In order to compare MC counting results of the different fixation methods, tissue shrinkage was taken into account. As even the same fixation caused shrinkage-differences between tissue from small and large intestine, different factors for each single fixation and intestinal localization had to be calculated. Tissue shrinkage varied between 19% and 57%, the highest tissue shrinkage was found after fixation with ZSF in the large intestine, the lowest one in the small intestine after lead acetate fixation. Our study emphasizes that MC counting results from

  13. Aurora A kinase RNAi and small molecule inhibition of Aurora kinases with VE-465 induce apoptotic death in multiple myeloma cells.

    Science.gov (United States)

    Evans, Robert; Naber, Claudia; Steffler, Tara; Checkland, Tamara; Keats, Jonathan; Maxwell, Christopher; Perry, Troy; Chau, Heidi; Belch, Andrew; Pilarski, Linda; Reiman, Tony

    2008-03-01

    The expression of RHAMM and other centrosome-associated genes are known to correlate with the extent of centrosome amplification in multiple myeloma, and with poor prognosis. RHAMM has a significant interaction with TPX2, a protein which regulates the localization and action of Aurora A kinase (AURKA) at the spindle poles. AURKA is known to be a central determinant of centrosome and spindle function and is a target for cancer therapy. Given these observations, we investigated the role of Aurora kinases as therapeutic targets in myeloma. Here we report that AURKA is expressed ubiquitously in myeloma, to varying degrees, in both cell lines and patients' bone marrow plasma cells. siRNA targeting AURKA induces apoptotic cell death in myeloma cell lines. The Aurora kinase inhibitor VE-465 also induces apoptosis and death in myeloma cell lines and primary myeloma plasma cells. The combination of VE-465 and dexamethasone improves cell killing compared with the use of either agent alone, even in cells resistant to the single agents. The phenotype of myeloma cells treated with VE-465 is consistent with published reports on the effects of Aurora kinase inhibition. Aurora kinase inhibitors should be pursued as potential treatments for myeloma.

  14. Determinants of cell-to-cell variability in protein kinase signaling.

    Science.gov (United States)

    Jeschke, Matthias; Baumgärtner, Stephan; Legewie, Stefan

    2013-01-01

    Cells reliably sense environmental changes despite internal and external fluctuations, but the mechanisms underlying robustness remain unclear. We analyzed how fluctuations in signaling protein concentrations give rise to cell-to-cell variability in protein kinase signaling using analytical theory and numerical simulations. We characterized the dose-response behavior of signaling cascades by calculating the stimulus level at which a pathway responds ('pathway sensitivity') and the maximal activation level upon strong stimulation. Minimal kinase cascades with gradual dose-response behavior show strong variability, because the pathway sensitivity and the maximal activation level cannot be simultaneously invariant. Negative feedback regulation resolves this trade-off and coordinately reduces fluctuations in the pathway sensitivity and maximal activation. Feedbacks acting at different levels in the cascade control different aspects of the dose-response curve, thereby synergistically reducing the variability. We also investigated more complex, ultrasensitive signaling cascades capable of switch-like decision making, and found that these can be inherently robust to protein concentration fluctuations. We describe how the cell-to-cell variability of ultrasensitive signaling systems can be actively regulated, e.g., by altering the expression of phosphatase(s) or by feedback/feedforward loops. Our calculations reveal that slow transcriptional negative feedback loops allow for variability suppression while maintaining switch-like decision making. Taken together, we describe design principles of signaling cascades that promote robustness. Our results may explain why certain signaling cascades like the yeast pheromone pathway show switch-like decision making with little cell-to-cell variability.

  15. Determinants of cell-to-cell variability in protein kinase signaling.

    Directory of Open Access Journals (Sweden)

    Matthias Jeschke

    Full Text Available Cells reliably sense environmental changes despite internal and external fluctuations, but the mechanisms underlying robustness remain unclear. We analyzed how fluctuations in signaling protein concentrations give rise to cell-to-cell variability in protein kinase signaling using analytical theory and numerical simulations. We characterized the dose-response behavior of signaling cascades by calculating the stimulus level at which a pathway responds ('pathway sensitivity' and the maximal activation level upon strong stimulation. Minimal kinase cascades with gradual dose-response behavior show strong variability, because the pathway sensitivity and the maximal activation level cannot be simultaneously invariant. Negative feedback regulation resolves this trade-off and coordinately reduces fluctuations in the pathway sensitivity and maximal activation. Feedbacks acting at different levels in the cascade control different aspects of the dose-response curve, thereby synergistically reducing the variability. We also investigated more complex, ultrasensitive signaling cascades capable of switch-like decision making, and found that these can be inherently robust to protein concentration fluctuations. We describe how the cell-to-cell variability of ultrasensitive signaling systems can be actively regulated, e.g., by altering the expression of phosphatase(s or by feedback/feedforward loops. Our calculations reveal that slow transcriptional negative feedback loops allow for variability suppression while maintaining switch-like decision making. Taken together, we describe design principles of signaling cascades that promote robustness. Our results may explain why certain signaling cascades like the yeast pheromone pathway show switch-like decision making with little cell-to-cell variability.

  16. Protein kinase C regulates human pluripotent stem cell self-renewal.

    Directory of Open Access Journals (Sweden)

    Masaki Kinehara

    Full Text Available The self-renewal of human pluripotent stem (hPS cells including embryonic stem and induced pluripotent stem cells have been reported to be supported by various signal pathways. Among them, fibroblast growth factor-2 (FGF-2 appears indispensable to maintain self-renewal of hPS cells. However, downstream signaling of FGF-2 has not yet been clearly understood in hPS cells.In this study, we screened a kinase inhibitor library using a high-throughput alkaline phosphatase (ALP activity-based assay in a minimal growth factor-defined medium to understand FGF-2-related molecular mechanisms regulating self-renewal of hPS cells. We found that in the presence of FGF-2, an inhibitor of protein kinase C (PKC, GF109203X (GFX, increased ALP activity. GFX inhibited FGF-2-induced phosphorylation of glycogen synthase kinase-3β (GSK-3β, suggesting that FGF-2 induced PKC and then PKC inhibited the activity of GSK-3β. Addition of activin A increased phosphorylation of GSK-3β and extracellular signal-regulated kinase-1/2 (ERK-1/2 synergistically with FGF-2 whereas activin A alone did not. GFX negated differentiation of hPS cells induced by the PKC activator, phorbol 12-myristate 13-acetate whereas Gö6976, a selective inhibitor of PKCα, β, and γ isoforms could not counteract the effect of PMA. Intriguingly, functional gene analysis by RNA interference revealed that the phosphorylation of GSK-3β was reduced by siRNA of PKCδ, PKCε, and ζ, the phosphorylation of ERK-1/2 was reduced by siRNA of PKCε and ζ, and the phosphorylation of AKT was reduced by PKCε in hPS cells.Our study suggested complicated cross-talk in hPS cells that FGF-2 induced the phosphorylation of phosphatidylinositol-3 kinase (PI3K/AKT, mitogen-activated protein kinase/ERK-1/2 kinase (MEK, PKC/ERK-1/2 kinase, and PKC/GSK-3β. Addition of GFX with a MEK inhibitor, U0126, in the presence of FGF-2 and activin A provided a long-term stable undifferentiated state of hPS cells even though h

  17. Protein Kinase C Regulates Human Pluripotent Stem Cell Self-Renewal

    Science.gov (United States)

    Kinehara, Masaki; Kawamura, Suguru; Tateyama, Daiki; Suga, Mika; Matsumura, Hiroko; Mimura, Sumiyo; Hirayama, Noriko; Hirata, Mitsuhi; Uchio-Yamada, Kozue; Kohara, Arihiro; Yanagihara, Kana; Furue, Miho K.

    2013-01-01

    Background The self-renewal of human pluripotent stem (hPS) cells including embryonic stem and induced pluripotent stem cells have been reported to be supported by various signal pathways. Among them, fibroblast growth factor-2 (FGF-2) appears indispensable to maintain self-renewal of hPS cells. However, downstream signaling of FGF-2 has not yet been clearly understood in hPS cells. Methodology/Principal Findings In this study, we screened a kinase inhibitor library using a high-throughput alkaline phosphatase (ALP) activity-based assay in a minimal growth factor-defined medium to understand FGF-2-related molecular mechanisms regulating self-renewal of hPS cells. We found that in the presence of FGF-2, an inhibitor of protein kinase C (PKC), GF109203X (GFX), increased ALP activity. GFX inhibited FGF-2-induced phosphorylation of glycogen synthase kinase-3β (GSK-3β), suggesting that FGF-2 induced PKC and then PKC inhibited the activity of GSK-3β. Addition of activin A increased phosphorylation of GSK-3β and extracellular signal-regulated kinase-1/2 (ERK-1/2) synergistically with FGF-2 whereas activin A alone did not. GFX negated differentiation of hPS cells induced by the PKC activator, phorbol 12-myristate 13-acetate whereas Gö6976, a selective inhibitor of PKCα, β, and γ isoforms could not counteract the effect of PMA. Intriguingly, functional gene analysis by RNA interference revealed that the phosphorylation of GSK-3β was reduced by siRNA of PKCδ, PKCε, and ζ, the phosphorylation of ERK-1/2 was reduced by siRNA of PKCε and ζ, and the phosphorylation of AKT was reduced by PKCε in hPS cells. Conclusions/Significance Our study suggested complicated cross-talk in hPS cells that FGF-2 induced the phosphorylation of phosphatidylinositol-3 kinase (PI3K)/AKT, mitogen-activated protein kinase/ERK-1/2 kinase (MEK), PKC/ERK-1/2 kinase, and PKC/GSK-3β. Addition of GFX with a MEK inhibitor, U0126, in the presence of FGF-2 and activin A provided a long

  18. Deoxynivalenol affects in vitro intestinal epithelial cell barrier integrity through inhibition of protein synthesis

    International Nuclear Information System (INIS)

    Van De Walle, Jacqueline; Sergent, Therese; Piront, Neil; Toussaint, Olivier; Schneider, Yves-Jacques; Larondelle, Yvan

    2010-01-01

    Deoxynivalenol (DON), one of the most common mycotoxin contaminants of raw and processed cereal food, adversely affects the gastrointestinal tract. Since DON acts as a protein synthesis inhibitor, the constantly renewing intestinal epithelium could be particularly sensitive to DON. We analyzed the toxicological effects of DON on intestinal epithelial protein synthesis and barrier integrity. Differentiated Caco-2 cells, as a widely used model of the human intestinal barrier, were exposed to realistic intestinal concentrations of DON (50, 500 and 5000 ng/ml) during 24 h. DON caused a concentration-dependent decrease in total protein content associated with a reduction in the incorporation of [ 3 H]-leucine, demonstrating its inhibitory effect on protein synthesis. DON simultaneously increased the paracellular permeability of the monolayer as reflected through a decreased transepithelial electrical resistance associated with an increased paracellular flux of the tracer [ 3 H]-mannitol. A concentration-dependent reduction in the expression level of the tight junction constituent claudin-4 was demonstrated by Western blot, which was not due to diminished transcription, increased degradation, or NF-κB, ERK or JNK activation, and was also observed for a tight junction independent protein, i.e. intestinal alkaline phosphatase. These results demonstrate a dual toxicological effect of DON on differentiated Caco-2 cells consisting in an inhibition of protein synthesis as well as an increase in monolayer permeability, and moreover suggest a possible link between them through diminished synthesis of the tight junction constituent claudin-4.

  19. Arctigenin from Fructus Arctii (Seed of Burdock) Reinforces Intestinal Barrier Function in Caco-2 Cell Monolayers

    Science.gov (United States)

    Shin, Hee Soon; Jung, Sun Young; Back, Su Yeon; Do, Jeong-Ryong; Shon, Dong-Hwa

    2015-01-01

    Fructus Arctii is used as a traditional herbal medicine to treat inflammatory diseases in oriental countries. This study aimed to investigate effect of F. Arctii extract on intestinal barrier function in human intestinal epithelial Caco-2 cells and to reveal the active component of F. Arctii. We measured transepithelial electrical resistance (TEER) value (as an index of barrier function) and ovalbumin (OVA) permeation (as an index of permeability) to observe the changes of intestinal barrier function. The treatment of F. Arctii increased TEER value and decreased OVA influx on Caco-2 cell monolayers. Furthermore, we found that arctigenin as an active component of F. Arctii increased TEER value and reduced permeability of OVA from apical to the basolateral side but not arctiin. In the present study, we revealed that F. Arctii could enhance intestinal barrier function, and its active component was an arctigenin on the functionality. We expect that the arctigenin from F. Arctii could contribute to prevention of inflammatory, allergic, and infectious diseases by reinforcing intestinal barrier function. PMID:26550018

  20. Arctigenin from Fructus Arctii (Seed of Burdock Reinforces Intestinal Barrier Function in Caco-2 Cell Monolayers

    Directory of Open Access Journals (Sweden)

    Hee Soon Shin

    2015-01-01

    Full Text Available Fructus Arctii is used as a traditional herbal medicine to treat inflammatory diseases in oriental countries. This study aimed to investigate effect of F. Arctii extract on intestinal barrier function in human intestinal epithelial Caco-2 cells and to reveal the active component of F. Arctii. We measured transepithelial electrical resistance (TEER value (as an index of barrier function and ovalbumin (OVA permeation (as an index of permeability to observe the changes of intestinal barrier function. The treatment of F. Arctii increased TEER value and decreased OVA influx on Caco-2 cell monolayers. Furthermore, we found that arctigenin as an active component of F. Arctii increased TEER value and reduced permeability of OVA from apical to the basolateral side but not arctiin. In the present study, we revealed that F. Arctii could enhance intestinal barrier function, and its active component was an arctigenin on the functionality. We expect that the arctigenin from F. Arctii could contribute to prevention of inflammatory, allergic, and infectious diseases by reinforcing intestinal barrier function.

  1. Raf Kinase Inhibitory Protein protects cells against locostatin-mediated inhibition of migration.

    Directory of Open Access Journals (Sweden)

    Anne N Shemon

    2009-06-01

    Full Text Available Raf Kinase Inhibitory Protein (RKIP, also PEBP1, a member of the Phosphatidylethanolamine Binding Protein family, negatively regulates growth factor signaling by the Raf/MAP kinase pathway. Since an organic compound, locostatin, was reported to bind RKIP and inhibit cell migration by a Raf-dependent mechanism, we addressed the role of RKIP in locostatin function.We analyzed locostatin interaction with RKIP and examined the biological consequences of locostatin binding on RKIP function. NMR studies show that a locostatin precursor binds to the conserved phosphatidylethanolamine binding pocket of RKIP. However, drug binding to the pocket does not prevent RKIP association with its inhibitory target, Raf-1, nor affect RKIP phosphorylation by Protein Kinase C at a regulatory site. Similarly, exposure of wild type, RKIP-depleted HeLa cells or RKIP-deficient (RKIP(-/- mouse embryonic fibroblasts (MEFs to locostatin has no effect on MAP kinase activation. Locostatin treatment of wild type MEFs causes inhibition of cell migration following wounding. RKIP deficiency impairs migration further, indicating that RKIP protects cells against locostatin-mediated inhibition of migration. Locostatin treatment of depleted or RKIP(-/- MEFs reveals cytoskeletal disruption and microtubule abnormalities in the spindle.These results suggest that locostatin's effects on cytoskeletal structure and migration are caused through mechanisms independent of its binding to RKIP and Raf/MAP kinase signaling. The protective effect of RKIP against drug inhibition of migration suggests a new role for RKIP in potentially sequestering toxic compounds that may have deleterious effects on cells.

  2. Raf Kinase Inhibitory Protein protects cells against locostatin-mediated inhibition of migration.

    Science.gov (United States)

    Shemon, Anne N; Eves, Eva M; Clark, Matthew C; Heil, Gary; Granovsky, Alexey; Zeng, Lingchun; Imamoto, Akira; Koide, Shohei; Rosner, Marsha Rich

    2009-06-24

    Raf Kinase Inhibitory Protein (RKIP, also PEBP1), a member of the Phosphatidylethanolamine Binding Protein family, negatively regulates growth factor signaling by the Raf/MAP kinase pathway. Since an organic compound, locostatin, was reported to bind RKIP and inhibit cell migration by a Raf-dependent mechanism, we addressed the role of RKIP in locostatin function. We analyzed locostatin interaction with RKIP and examined the biological consequences of locostatin binding on RKIP function. NMR studies show that a locostatin precursor binds to the conserved phosphatidylethanolamine binding pocket of RKIP. However, drug binding to the pocket does not prevent RKIP association with its inhibitory target, Raf-1, nor affect RKIP phosphorylation by Protein Kinase C at a regulatory site. Similarly, exposure of wild type, RKIP-depleted HeLa cells or RKIP-deficient (RKIP(-/-)) mouse embryonic fibroblasts (MEFs) to locostatin has no effect on MAP kinase activation. Locostatin treatment of wild type MEFs causes inhibition of cell migration following wounding. RKIP deficiency impairs migration further, indicating that RKIP protects cells against locostatin-mediated inhibition of migration. Locostatin treatment of depleted or RKIP(-/-) MEFs reveals cytoskeletal disruption and microtubule abnormalities in the spindle. These results suggest that locostatin's effects on cytoskeletal structure and migration are caused through mechanisms independent of its binding to RKIP and Raf/MAP kinase signaling. The protective effect of RKIP against drug inhibition of migration suggests a new role for RKIP in potentially sequestering toxic compounds that may have deleterious effects on cells.

  3. AMP-activated protein kinase induces actin cytoskeleton reorganization in epithelial cells

    International Nuclear Information System (INIS)

    Miranda, Lisa; Carpentier, Sarah; Platek, Anna; Hussain, Nusrat; Gueuning, Marie-Agnes; Vertommen, Didier; Ozkan, Yurda; Sid, Brice; Hue, Louis; Courtoy, Pierre J.; Rider, Mark H.; Horman, Sandrine

    2010-01-01

    AMP-activated protein kinase (AMPK), a known regulator of cellular and systemic energy balance, is now recognized to control cell division, cell polarity and cell migration, all of which depend on the actin cytoskeleton. Here we report the effects of A769662, a pharmacological activator of AMPK, on cytoskeletal organization and signalling in epithelial Madin-Darby canine kidney (MDCK) cells. We show that AMPK activation induced shortening or radiation of stress fibers, uncoupling from paxillin and predominance of cortical F-actin. In parallel, Rho-kinase downstream targets, namely myosin regulatory light chain and cofilin, were phosphorylated. These effects resembled the morphological changes in MDCK cells exposed to hyperosmotic shock, which led to Ca 2+ -dependent AMPK activation via calmodulin-dependent protein kinase kinase-β(CaMKKβ), a known upstream kinase of AMPK. Indeed, hypertonicity-induced AMPK activation was markedly reduced by the STO-609 CaMKKβ inhibitor, as was the increase in MLC and cofilin phosphorylation. We suggest that AMPK links osmotic stress to the reorganization of the actin cytoskeleton.

  4. Inhibition of Rho-associated kinases disturbs the collective cell migration of stratified TE-10 cells

    Directory of Open Access Journals (Sweden)

    Taro Mikami

    2015-01-01

    Full Text Available BACKGROUND: The collective cell migration of stratified epithelial cells is considered to be an important phenomenon in wound healing, development, and cancer invasion; however, little is known about the mechanisms involved. Furthermore, whereas Rho family proteins, including RhoA, play important roles in cell migration, the exact role of Rho-associated coiled coil-containing protein kinases (ROCKs in cell migration is controversial and might be cell-type dependent. Here, we report the development of a novel modified scratch assay that was used to observe the collective cell migration of stratified TE-10 cells derived from a human esophageal cancer specimen. RESULTS: Desmosomes were found between the TE-10 cells and microvilli of the surface of the cell sheet. The leading edge of cells in the cell sheet formed a simple layer and moved forward regularly; these rows were followed by the stratified epithelium. ROCK inhibitors and ROCK small interfering RNAs (siRNAs disturbed not only the collective migration of the leading edge of this cell sheet, but also the stratified layer in the rear. In contrast, RhoA siRNA treatment resulted in more rapid migration of the leading rows and disturbed movement of the stratified portion. CONCLUSIONS: The data presented in this study suggest that ROCKs play an important role in mediating the collective migration of TE-10 cell sheets. In addition, differences between the effects of siRNAs targeting either RhoA or ROCKs suggested that distinct mechanisms regulate the collective cell migration in the simple epithelium of the wound edge versus the stratified layer of the epithelium.

  5. A Unique Cause of Intestinal and Splenic Infarction in a Sickle Cell Trait Patient

    OpenAIRE

    Asfaw, Sofya H.; Falk, Gavin A.; Morris-Stiff, Gareth; Tuthill, Ralph J.; Moorman, Matthew L.; Samotowka, Michael A.

    2013-01-01

    Sickle-cell trait is a common genetic abnormality in the African American population. A sickle-cell crisis in a patient with sickle-cell trait is uncommon at best. Abdominal painful crises are typical of patients with sickle cell anemia. The treatment for an abdominal painful crisis is usually medical and rarely surgical. We present the case of a cocaine-induced sickle-cell crisis in a sickle-cell trait patient that resulted in splenic, intestinal, and cerebral infarctions and multisystem org...

  6. Mixed lineage kinase 3 is required for matrix metalloproteinase expression and invasion in ovarian cancer cells

    International Nuclear Information System (INIS)

    Zhan, Yu; Abi Saab, Widian F.; Modi, Nidhi; Stewart, Amanda M.; Liu, Jinsong; Chadee, Deborah N.

    2012-01-01

    Mixed lineage kinase 3 (MLK3) is a mitogen-activated protein kinase kinase kinase (MAP3K) that activates MAPK signaling pathways and regulates cellular responses such as proliferation, migration and apoptosis. Here we report high levels of total and phospho-MLK3 in ovarian cancer cell lines in comparison to immortalized nontumorigenic ovarian epithelial cell lines. Using small interfering RNA (siRNA)-mediated gene silencing, we determined that MLK3 is required for the invasion of SKOV3 and HEY1B ovarian cancer cells. Furthermore, mlk3 silencing substantially reduced matrix metalloproteinase (MMP)-1, -2, -9 and -12 gene expression and MMP-2 and -9 activities in SKOV3 and HEY1B ovarian cancer cells. MMP-1, -2, -9 and-12 expression, and MLK3-induced activation of MMP-2 and MMP-9 requires both extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) activities. In addition, inhibition of activator protein-1 (AP-1) reduced MMP-1, MMP-9 and MMP-12 gene expression. Collectively, these findings establish MLK3 as an important regulator of MMP expression and invasion in ovarian cancer cells. -- Highlights: ► Ovarian cancer cell lines have high levels of total and phosphorylated MLK3. ► MLK3 is required for MMP expression and activity in ovarian cancer cells. ► MLK3 is required for invasion of SKOV3 and HEY1B ovarian cancer cells. ► MLK3-dependent regulation of MMP-2 and MMP-9 activities requires ERK and JNK.

  7. Gut-associated lymphoid tissue, T cell trafficking, and chronic intestinal inflammation.

    Science.gov (United States)

    Koboziev, Iurii; Karlsson, Fridrik; Grisham, Matthew B

    2010-10-01

    The etiologies of the inflammatory bowel diseases (IBD; Crohn's disease, ulcerative colitis) have not been fully elucidated. However, there is very good evidence implicating T cell and T cell trafficking to the gut and its associated lymphoid tissue as important components in disease pathogenesis. The objective of this review is to provide an overview of the mechanisms involved in naive and effector T cell trafficking to the gut-associated lymphoid tissue (GALT; Peyer's patches, isolated lymphoid follicles), mesenteric lymph nodes and intestine in response to commensal enteric antigens under physiological conditions as well as during the induction of chronic gut inflammation. In addition, recent data suggests that the GALT may not be required for enteric antigen-driven intestinal inflammation in certain mouse models of IBD. These new data suggest a possible paradigm shift in our understanding of how and where naive T cells become activated to yield disease-producing effector cells. © 2010 New York Academy of Sciences.

  8. Insulin resistance enhances the mitogen-activated protein kinase signaling pathway in ovarian granulosa cells.

    Directory of Open Access Journals (Sweden)

    Linghui Kong

    Full Text Available The ovary is the main regulator of female fertility. Granulosa cell dysfunction may be involved in various reproductive endocrine disorders. Here we investigated the effect of insulin resistance on the metabolism and function of ovarian granulosa cells, and dissected the functional status of the mitogen-activated protein kinase signaling pathway in these cells. Our data showed that dexamethasone-induced insulin resistance in mouse granulosa cells reduced insulin sensitivity, accompanied with an increase in phosphorylation of p44/42 mitogen-activated protein kinase. Furthermore, up-regulation of cytochrome P450 subfamily 17 and testosterone and down-regulation of progesterone were observed in insulin-resistant mouse granulosa cells. Inhibition of p44/42 mitogen-activated protein kinase after induction of insulin resistance in mouse granulosa cells decreased phosphorylation of p44/42 mitogen-activated protein kinase, downregulated cytochrome P450 subfamily 17 and lowered progesterone production. This insulin resistance cell model can successfully demonstrate certain mechanisms such as hyperandrogenism, which may inspire a new strategy for treating reproductive endocrine disorders by regulating cell signaling pathways.

  9. Pyruvate Kinase Triggers a Metabolic Feedback Loop that Controls Redox Metabolism in Respiring Cells

    NARCIS (Netherlands)

    Grüning, N.M.; Rinnerthaler, M.; Bluemlein, K.; Mulleder, M.; Wamelink, M.M.C.; Lehrach, H.; Jakobs, C.A.J.M.; Breitenbach, M.; Ralser, M.

    2011-01-01

    In proliferating cells, a transition from aerobic to anaerobic metabolism is known as the Warburg effect, whose reversal inhibits cancer cell proliferation. Studying its regulator pyruvate kinase (PYK) in yeast, we discovered that central metabolism is self-adapting to synchronize redox metabolism

  10. Radiosensitivity of mice of different lines and age as determinated with reference to ''intestinal'' death and DNA repair in intestinal epithelium cells

    International Nuclear Information System (INIS)

    Konoplyannikova, O.A.; Sklobovskaya, M.V.; Konoplyannikov, A.G.; Saenko, A.S.

    1982-01-01

    A study was made of the influence of strain- and age-related differences on mouse mortality after irradiation with doses lying within the ''intest+nal'' dose range, and also damages to stem cells of intestinal epithelium and induction and repair of single-strand DNA breaks in intestinal epitherium cells. Mice of different lines and age vary in LDsub(50/4) and stem cell radiosensitivity. There are no differences in the sedimentation constants of DNA fragments in alkaline lysates of intestinal crypts of intact mice of different age. Radiosensitivity determined with reference to single-strand breaks induction in DNA is similar with different mo use groups. Repair of single-strand DNA breaks of eldery mice is slower than that of young animals

  11. Biogenic amines as regulators of the proliferative activity of normal and neoplastic intestinal epithelial cells (review).

    Science.gov (United States)

    Tutton, P J; Barkla, D H

    1987-01-01

    The role of extracellular amines such as noradrenaline and serotonin and their interaction with cyclic nucleotides and intracellular polyamines in the regulation of intestinal epithelial cell proliferation is reviewed with particular reference to the differences between normal and neoplastic cells. In respect to the normal epithelium of the small intestine there is a strong case to support the notion that cell proliferation is controlled by, amongst other things, sympathetic nerves. In colonic carcinomas, antagonists for certain serotonin receptors, for histamine H2 receptors and for dopamine D2 receptors inhibit both cell division and tumour growth. Because of the reproducible variations between tumour lines in the response to these antagonists, this inhibition appears to be due to a direct effect on the tumour cells rather than an indirect effect via the tumour host or stroma. This conclusion is supported by the cytocidal effects of toxic congeners of serotonin on the tumour cells. The most salient difference between the amine responses of normal and neoplastic cells relates to the issue of amine uptake. Proliferation of crypt cells is promoted by amine uptake inhibitors, presumably because they block amine re-uptake by the amine secreting cells--sympathetic neurones and enteroendocrine cells. However, tumour cell proliferation is strongly inhibited by amine uptake inhibitors, suggesting that neoplastic cells can, and need to take up the amine before being stimulated by it. Recent revelations in the field of oncogenes also support an important association between amines, cyclic nucleotides and cell division. The ras oncogenes code for a protein that is a member of a family of molecules which relay information from extracellular regulators, such as biogenic amines, to the intracellular regulators, including cyclic nucleotides. Evidence is presented suggesting that enteroendocrine cells, enterocytes, carcinoid tumour cells and adenocarcinoma cells all have the same

  12. The alteration in intestinal secretory immunoglobulin A and its secreting cells during ischemia/reperfusion injury

    Directory of Open Access Journals (Sweden)

    Li-qun SUN

    2012-04-01

    Full Text Available Objective To investigate the change in intestinal secretion immunoglobulin A (sIgA level and IgA-secreting cells during ischemia/reperfusion (I/R injury. Methods Forty-eight BALB/c mice were randomly divided into 6 experimental groups in accordance with different reperfusion times (R2h, R6h, R12h, R24h, and R72h group, and one sham group (n=8. Bacterial translocation to distant organs (lung, spleen, and mesenteric lymph nodes was observed. The sIgA level of the intestinal tract was measured by enzyme-linked immunosorbent assay (ELISA. The B cell subgroup in the lymphocytes related to the intestinal tract was measured by flow cytometry. Results The bacterial translocation occurred during I/R injury, and the intestinal sIgA level decreased, and they showed an obvious negative correlation (r2=0.729. With the increase in intestinal I/R injury, the ratio of IgM+B220+ cells in the gut-associated lymphoid tissue increased, whereas the proportion of IgA+B220+ cells decreased. The most significant change was found in R12h group (P < 0.01. Conclusions The proportion of IgM+ B cells in the gut-associated lymphoid tissue increased, whereas that of IgA+ B cells reduced during I/R injury. These phenomena may cause sIgA level to reduce and bacterial translocation of the distant organs to occur.

  13. Cell lineage identification and stem cell culture in a porcine model for the study of intestinal epithelial regeneration.

    Directory of Open Access Journals (Sweden)

    Liara M Gonzalez

    Full Text Available Significant advances in intestinal stem cell biology have been made in murine models; however, anatomical and physiological differences between mice and humans limit mice as a translational model for stem cell based research. The pig has been an effective translational model, and represents a candidate species to study intestinal epithelial stem cell (IESC driven regeneration. The lack of validated reagents and epithelial culture methods is an obstacle to investigating IESC driven regeneration in a pig model. In this study, antibodies against Epithelial Adhesion Molecule 1 (EpCAM and Villin marked cells of epithelial origin. Antibodies against Proliferative Cell Nuclear Antigen (PCNA, Minichromosome Maintenance Complex 2 (MCM2, Bromodeoxyuridine (BrdU and phosphorylated Histone H3 (pH3 distinguished proliferating cells at various stages of the cell cycle. SOX9, localized to the stem/progenitor cells zone, while HOPX was restricted to the +4/'reserve' stem cell zone. Immunostaining also identified major differentiated lineages. Goblet cells were identified by Mucin 2 (MUC2; enteroendocrine cells by Chromogranin A (CGA, Gastrin and Somatostatin; and absorptive enterocytes by carbonic anhydrase II (CAII and sucrase isomaltase (SIM. Transmission electron microscopy demonstrated morphologic and sub-cellular characteristics of stem cell and differentiated intestinal epithelial cell types. Quantitative PCR gene expression analysis enabled identification of stem/progenitor cells, post mitotic cell lineages, and important growth and differentiation pathways. Additionally, a method for long-term culture of porcine crypts was developed. Biomarker characterization and development of IESC culture in the porcine model represents a foundation for translational studies of IESC-driven regeneration of the intestinal epithelium in physiology and disease.

  14. Distribution and characterisation of CCK containing enteroendocrine cells of the mouse small and large intestine

    DEFF Research Database (Denmark)

    Fakhry, Josiane; Wang, Joyce; Martins, Patricia

    2017-01-01

    but positive cells were rare in the rectum. Immunoreactive EEC were as common in the caecum and proximal colon as they were in the duodenum and jejunum. CCK gene transcripts were found in the mucosa throughout the intestine but mRNA for gastrin, a hormone that can bind some anti-CCK antibodies, was only found...

  15. Impact of thymectomy and antilymphocytic serum on stem cells of the intestinal epithelium

    International Nuclear Information System (INIS)

    Aparovich, G.G.; Trufakin, V.A.

    1982-01-01

    The population of stem cells of the intestinal epithelium was studied under conditions of the disturbed balance in the immune system on F 1 (CBAxC57B1) mice. It has been shown that thymectomy in adult mice does not influence the stem region of the intestinal epithelium at early time of observation but causes a tendency to the changed number of epithelial stem cells in 4-6 months. Administration of specific sera against T-, B- and mixed lymphoid populations on the 1st day of observation produces an ambi us effect on the stem region and results in an increase of the number of epithelial stem cells on the 5th day. After administration of the antilymphocytic serum there have been determined morphological changes in the population of mature erythrocytes and undulatory fluctuations in the number of mitotic cells of the intestinal epithelium. These data suggest functional correlation of the intestinal epithelium and the state of the immunocompetent tissue [ru

  16. Characterizing microbiota-independent effects of oligosaccharides on intestinal epithelial cells

    NARCIS (Netherlands)

    Akbari, Peyman; Fink-Gremmels, Johanna; Willems, Rianne H.A.M.; Difilippo, Elisabetta; Schols, Henk A.; Schoterman, Margriet H.C.; Garssen, Johan; Braber, Saskia

    2017-01-01

    Purpose: The direct effects of galacto-oligosaccharides (GOS), including Vivinal® GOS syrup (VGOS) and purified Vivinal® GOS (PGOS), on the epithelial integrity and corresponding interleukin-8 (IL-8/CXCL8) release were examined in a Caco-2 cell model for intestinal barrier dysfunction. To

  17. Intestinal handling-induced mast cell activation and inflammation in human postoperative ileus

    NARCIS (Netherlands)

    The, F. O.; Bennink, R. J.; Ankum, W. M.; Buist, M. R.; Busch, O. R. C.; Gouma, D. J.; van der Heide, S.; van den Wijngaard, R. M.; de Jonge, W. J.; Boeckxstaens, G. E.

    2008-01-01

    Background: Murine postoperative ileus results from intestinal inflammation triggered by manipulation-induced mast cell activation. As its extent depends on the degree of handling and subsequent inflammation, it is hypothesised that the faster recovery after minimal invasive surgery results from

  18. Intestinal handling-induced mast cell activation and inflammation in human postoperative ileus

    NARCIS (Netherlands)

    The, F. O.; Bennink, R. J.; Ankum, W. M.; Buist, M. R.; Busch, O. R. C.; Gouma, D. J.; Van der Heide, S.; van den Wijngaard, R. M.; Boeckxstaens, G. E.; de Jonge, Wouter J.

    Background: Murine postoperative ileus results from intestinal inflammation triggered by manipulation-induced mast cell activation. As its extent depends on the degree of handling and subsequent inflammation, it is hypothesised that the faster recovery after minimal invasive surgery results from

  19. [Effect of inhibitors serine/threonine protein kinases and protein phosphatases on mitosis progression of synchronized tobacco by-2 cells].

    Science.gov (United States)

    Sheremet, Ia A; Emets, A I; Azmi, A; Vissenberg, K; Verbelen, J-P; Blium, Ia B

    2012-01-01

    In order to investigate the role of various serine/ threonine protein kinases and protein phosphatases in the regulation of mitosis progression in plant cells the influence of cyclin-dependent (olomoucine) and Ca2+ -calmodulin-dependent (W7) protein kinases inhibitors, as well as protein kinase C inhibitors (H7 and staurosporine) and protein phosphatases inhibitor (okadaic acid) on mitosis progression in synchronized tobacco BY-2 cells has been studied. It was found that BY-2 culture treatment with inhibitors of cyclin dependent protein kinases and protein kinase C causes prophase delay, reduces the mitotic index and displaces of mitotic peak as compare with control cells. Inhibition of Ca2+ -calmodulin dependent protein kinases enhances the cell entry into prophase and delays their exit from mitosis. Meanwhile inhibition of serine/threonine protein phosphatases insignificantly enhances of synchronized BY-2 cells entering into all phases of mitosis.

  20. Poliovirus mutants excreted by a chronically infected hypogammaglobulinemic patient establish persistent infections in human intestinal cells

    International Nuclear Information System (INIS)

    Labadie, Karine; Pelletier, Isabelle; Saulnier, Aure; Martin, Javier; Colbere-Garapin, Florence

    2004-01-01

    Immunodeficient patients whose gut is chronically infected by vaccine-derived poliovirus (VDPV) may excrete large amounts of virus for years. To investigate how poliovirus (PV) establishes chronic infections in the gut, we tested whether it is possible to establish persistent VDPV infections in human intestinal Caco-2 cells. Four type 3 VDPV mutants, representative of the viral evolution in the gut of a hypogammaglobulinemic patient over almost 2 years [J. Virol. 74 (2000) 3001], were used to infect both undifferentiated, dividing cells, and differentiated, polarized enterocytes. A VDPV mutant excreted 36 days postvaccination by the patient was lytic in both types of intestinal cell cultures, like the parental Sabin 3 (S3) strain. In contrast, three VDPVs excreted 136, 442, and 637 days postvaccination, established persistent infections both in undifferentiated cells and in enterocytes. Thus, viral determinants selected between day 36 and 136 conferred on VDPV mutants the capacity to infect intestinal cells persistently. The percentage of persistently VDPV-infected cultures was higher in enterocytes than in undifferentiated cells, implicating cellular determinants involved in the differentiation of enterocytes in persistent VDPV infections. The establishment of persistent infections in enterocytes was not due to poor replication of VDPVs in these cells, but was associated with reduced viral adsorption to the cell surface

  1. Genome-wide RNAi Screen Identifies Networks Involved in Intestinal Stem Cell Regulation in Drosophila

    Directory of Open Access Journals (Sweden)

    Xiankun Zeng

    2015-02-01

    Full Text Available The intestinal epithelium is the most rapidly self-renewing tissue in adult animals and maintained by intestinal stem cells (ISCs in both Drosophila and mammals. To comprehensively identify genes and pathways that regulate ISC fates, we performed a genome-wide transgenic RNAi screen in adult Drosophila intestine and identified 405 genes that regulate ISC maintenance and lineage-specific differentiation. By integrating these genes into publicly available interaction databases, we further developed functional networks that regulate ISC self-renewal, ISC proliferation, ISC maintenance of diploid status, ISC survival, ISC-to-enterocyte (EC lineage differentiation, and ISC-to-enteroendocrine (EE lineage differentiation. By comparing regulators among ISCs, female germline stem cells, and neural stem cells, we found that factors related to basic stem cell cellular processes are commonly required in all stem cells, and stem-cell-specific, niche-related signals are required only in the unique stem cell type. Our findings provide valuable insights into stem cell maintenance and lineage-specific differentiation.

  2. Stem Cells in the Intestine: Possible Roles in Pathogenesis of Irritable Bowel Syndrome.

    Science.gov (United States)

    Ratanasirintrawoot, Sutheera; Israsena, Nipan

    2016-07-30

    Irritable bowel syndrome is one of the most common functional gastrointestinal (GI) disorders that significantly impair quality of life in patients. Current available treatments are still not effective and the pathophysiology of this condition remains unclearly defined. Recently, research on intestinal stem cells has greatly advanced our understanding of various GI disorders. Alterations in conserved stem cell regulatory pathways such as Notch, Wnt, and bone morphogenic protein/TGF- β have been well documented in diseases such as inflammatory bowel diseases and cancer. Interaction between intestinal stem cells and various signals from their environment is important for the control of stem cell self-renewal, regulation of number and function of specific intestinal cell types, and maintenance of the mucosal barrier. Besides their roles in stem cell regulation, these signals are also known to have potent effects on immune cells, enteric nervous system and secretory cells in the gut, and may be responsible for various aspects of pathogenesis of functional GI disorders, including visceral hypersensitivity, altered gut motility and low grade gut inflammation. In this article, we briefly summarize the components of these signaling pathways, how they can be modified by extrinsic factors and novel treatments, and provide evidenced support of their roles in the inflammation processes. Furthermore, we propose how changes in these signals may contribute to the symptom development and pathogenesis of irritable bowel syndrome.

  3. p70S6 kinase signals cell survival as well as growth, inactivating the pro-apoptotic molecule BAD

    DEFF Research Database (Denmark)

    Harada, H; Andersen, Jens S.; Mann, M

    2001-01-01

    Cytokines often deliver simultaneous, yet distinct, cell growth and cell survival signals. The 70-kDa ribosomal protein S6 kinase (p70S6K) is known to regulate cell growth by inducing protein synthesis components. We purified membrane-based p70S6K as a kinase responsible for site-specific phospho...

  4. Differential effects on cell motility, embryonic stem cell self-renewal and senescence by diverse Src kinase family inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Tamm, Christoffer, E-mail: christoffer.tamm@imbim.uu.se; Galito, Sara Pijuan, E-mail: sara.pijuan@imbim.uu.se; Anneren, Cecilia, E-mail: cecilia.anneren@imbim.uu.se

    2012-02-15

    The Src family of non-receptor tyrosine kinases (SFKs) has been shown to play an intricate role in embryonic stem (ES) cell maintenance. In the present study we have focused on the underlying molecular mechanisms responsible for the vastly different effects induced by various commonly used SFK inhibitors. We show that several diverse cell types, including fibroblasts completely lacking SFKs, cannot undergo mitosis in response to SU6656 and that this is caused by an unselective inhibition of Aurora kinases. In contrast, PP2 and PD173952 block motility immediately upon exposure and forces cells to grow in dense colonies. The subsequent halt in proliferation of fibroblast and epithelial cells in the center of the colonies approximately 24 h post-treatment appears to be caused by cell-to-cell contact inhibition rather than a direct effect of SFK kinase inhibition. Interestingly, in addition to generating more homogenous and dense ES cell cultures, without any diverse effect on proliferation, PP2 and PD173652 also promote ES cell self-renewal by reducing the small amount of spontaneous differentiation typically observed under standard ES cell culture conditions. These effects could not be mirrored by the use of Gleevec, a potent inhibitor of c-Abl and PDGFR kinases that are also inhibited by PP2. -- Highlights: Black-Right-Pointing-Pointer SFK inhibitor SU6656 induces senescence in mouse ES cells. Black-Right-Pointing-Pointer SU6656 inhibits mitosis in a SFK-independent manner via cross-selectivity for Aurora kinases. Black-Right-Pointing-Pointer SFK inhibitor PP2 impairs cell motility in various cell lines, including mouse ES cells. Black-Right-Pointing-Pointer Ensuing impeded motility, PP2 inhibits proliferation of various cells lines except for mouse ES cells. Black-Right-Pointing-Pointer SFK inhibitors PP2 and PD173952 impede spontaneous differentiation in standard mouse ES culture maintenance.

  5. Differential effects on cell motility, embryonic stem cell self-renewal and senescence by diverse Src kinase family inhibitors

    International Nuclear Information System (INIS)

    Tamm, Christoffer; Galitó, Sara Pijuan; Annerén, Cecilia

    2012-01-01

    The Src family of non-receptor tyrosine kinases (SFKs) has been shown to play an intricate role in embryonic stem (ES) cell maintenance. In the present study we have focused on the underlying molecular mechanisms responsible for the vastly different effects induced by various commonly used SFK inhibitors. We show that several diverse cell types, including fibroblasts completely lacking SFKs, cannot undergo mitosis in response to SU6656 and that this is caused by an unselective inhibition of Aurora kinases. In contrast, PP2 and PD173952 block motility immediately upon exposure and forces cells to grow in dense colonies. The subsequent halt in proliferation of fibroblast and epithelial cells in the center of the colonies approximately 24 h post-treatment appears to be caused by cell-to-cell contact inhibition rather than a direct effect of SFK kinase inhibition. Interestingly, in addition to generating more homogenous and dense ES cell cultures, without any diverse effect on proliferation, PP2 and PD173652 also promote ES cell self-renewal by reducing the small amount of spontaneous differentiation typically observed under standard ES cell culture conditions. These effects could not be mirrored by the use of Gleevec, a potent inhibitor of c-Abl and PDGFR kinases that are also inhibited by PP2. -- Highlights: ► SFK inhibitor SU6656 induces senescence in mouse ES cells. ► SU6656 inhibits mitosis in a SFK-independent manner via cross-selectivity for Aurora kinases. ► SFK inhibitor PP2 impairs cell motility in various cell lines, including mouse ES cells. ► Ensuing impeded motility, PP2 inhibits proliferation of various cells lines except for mouse ES cells. ► SFK inhibitors PP2 and PD173952 impede spontaneous differentiation in standard mouse ES culture maintenance.

  6. Bromovinyl-deoxyuridine: A selective substrate for mitochondrial thymidine kinase in cell extracts

    International Nuclear Information System (INIS)

    Franzolin, Elisa; Rampazzo, Chiara; Perez-Perez, Maria-Jesus; Hernandez, Ana-Isabel; Balzarini, Jan; Bianchi, Vera

    2006-01-01

    Cellular models of mitochondrial thymidine kinase (TK2) deficiency require a reliable method to measure TK2 activity in whole cell extracts containing two interfering deoxyribonucleoside kinases, thymidine kinase 1 (TK1) and deoxycytidine kinase. We tested the value of the thymidine analog (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU) as a TK2-specific substrate. With extracts of OSTTK1 - cells containing TK2 as the only thymidine kinase and a highly specific TK2 inhibitor we established conditions to detect the low TK2 activity commonly present in cells. With extracts of TK1-proficient osteosarcoma cells and normal human fibroblasts we showed that BVDU, but not 1-(β-D-arabinofuranosyl)thymine (Ara-T), discriminates TK2 activity even in the presence of 100-fold excess TK1. A comparison with current procedures based on TK2 inhibition demonstrated the better performance of the new TK2 assay. When cultured human fibroblasts passed from proliferation to quiescence TK2 activity increased by 3-fold, stressing the importance of TK2 function in the absence of TK1

  7. Bromovinyl-deoxyuridine: A selective substrate for mitochondrial thymidine kinase in cell extracts.

    Science.gov (United States)

    Franzolin, Elisa; Rampazzo, Chiara; Pérez-Pérez, María-Jesús; Hernández, Ana-Isabel; Balzarini, Jan; Bianchi, Vera

    2006-05-26

    Cellular models of mitochondrial thymidine kinase (TK2) deficiency require a reliable method to measure TK2 activity in whole cell extracts containing two interfering deoxyribonucleoside kinases, thymidine kinase 1 (TK1) and deoxycytidine kinase. We tested the value of the thymidine analog (E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU) as a TK2-specific substrate. With extracts of OSTTK1- cells containing TK2 as the only thymidine kinase and a highly specific TK2 inhibitor we established conditions to detect the low TK2 activity commonly present in cells. With extracts of TK1-proficient osteosarcoma cells and normal human fibroblasts we showed that BVDU, but not 1-(beta-d-arabinofuranosyl)thymine (Ara-T), discriminates TK2 activity even in the presence of 100-fold excess TK1. A comparison with current procedures based on TK2 inhibition demonstrated the better performance of the new TK2 assay. When cultured human fibroblasts passed from proliferation to quiescence TK2 activity increased by 3-fold, stressing the importance of TK2 function in the absence of TK1.

  8. Rorγt+ innate lymphoid cells in intestinal homeostasis and immunity.

    Science.gov (United States)

    Aparicio-Domingo, Patricia; Cupedo, Tom

    2011-01-01

    Innate lymphoid cells (ILC) combine innate and adaptive immune functions and are part of the first line of defense against mucosal infections. ILC are set apart from adaptive lymphocytes by their independence on RAG genes and the resulting absence of specific antigen receptors. In this review, we will discuss the biology and function of intestinal ILC that express the nuclear hormone receptor Rorγt (encoded by the Rorc gene) and highlight their role in intestinal homeostasis and immunity. Copyright © 2011 S. Karger AG, Basel.

  9. Quantitative rather than qualitative differences in gene expression predominate in intestinal cell maturation along distinct cell lineages

    International Nuclear Information System (INIS)

    Velcich, Anna; Corner, Georgia; Paul, Doru; Zhuang Min; Mariadason, John M.; Laboisse, Christian; Augenlicht, Leonard

    2005-01-01

    Several cell types are present in the intestinal epithelium that likely arise from a common precursor, the stem cell, and each mature cell type expresses a unique set of genes that characterizes its functional phenotype. Although the process of differentiation is intimately linked to the cessation of proliferation, the mechanisms that dictate intestinal cell fate determination are not well characterized. To investigate the reprogramming of gene expression during the cell lineage allocation/differentiation process, we took advantage of a unique system of two clonal derivatives of HT29 cells, Cl16E and Cl19A cells, which spontaneously differentiate as mucus producing goblet and chloride-secreting cells, respectively, as a function of time. By profiling gene expression, we found that these two cell lines show remarkably similar kinetics of change in gene expression and common clusters of coordinately regulated genes. This demonstrates that lineage-specific differentiation of intestinal epithelial cells is characterized overall by the sequential recruitment of functionally similar gene sets independent of the final phenotype of the mature cells

  10. Hsp90 inhibition differentially destabilises MAP kinase and TGF-beta signalling components in cancer cells revealed by kinase-targeted chemoproteomics

    International Nuclear Information System (INIS)

    Haupt, Armin; Dahl, Andreas; Lappe, Michael; Lehrach, Hans; Gonzalez, Cayetano; Drewes, Gerard; Lange, Bodo MH; Joberty, Gerard; Bantscheff, Marcus; Fröhlich, Holger; Stehr, Henning; Schweiger, Michal R; Fischer, Axel; Kerick, Martin; Boerno, Stefan T

    2012-01-01

    The heat shock protein 90 (Hsp90) is required for the stability of many signalling kinases. As a target for cancer therapy it allows the simultaneous inhibition of several signalling pathways. However, its inhibition in healthy cells could also lead to severe side effects. This is the first comprehensive analysis of the response to Hsp90 inhibition at the kinome level. We quantitatively profiled the effects of Hsp90 inhibition by geldanamycin on the kinome of one primary (Hs68) and three tumour cell lines (SW480, U2OS, A549) by affinity proteomics based on immobilized broad spectrum kinase inhibitors ('kinobeads'). To identify affected pathways we used the KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway classification. We combined Hsp90 and proteasome inhibition to identify Hsp90 substrates in Hs68 and SW480 cells. The mutational status of kinases from the used cell lines was determined using next-generation sequencing. A mutation of Hsp90 candidate client RIPK2 was mapped onto its structure. We measured relative abundances of > 140 protein kinases from the four cell lines in response to geldanamycin treatment and identified many new potential Hsp90 substrates. These kinases represent diverse families and cellular functions, with a strong representation of pathways involved in tumour progression like the BMP, MAPK and TGF-beta signalling cascades. Co-treatment with the proteasome inhibitor MG132 enabled us to classify 64 kinases as true Hsp90 clients. Finally, mutations in 7 kinases correlate with an altered response to Hsp90 inhibition. Structural modelling of the candidate client RIPK2 suggests an impact of the mutation on a proposed Hsp90 binding domain. We propose a high confidence list of Hsp90 kinase clients, which provides new opportunities for targeted and combinatorial cancer treatment and diagnostic applications

  11. The crypt and cell size kinetics in the irradiated intestinal epithelium in mice

    International Nuclear Information System (INIS)

    Kononenko, A.M.; Gagarin, A.U.

    1975-01-01

    A study has been made of changes in the average values of the axial cross-sectional area of the crypt and of cell area in this cross-section for eight days after a single whole-body exposure of male mice to 400 rad of X-rays. A small reduction in the crypt area in the destructive period gives way to a much greater increase in the normal dimensions of the area in the regenerative period. Two very considerable waves of anomalous increase are observed in the dimensions of the cryptal cell cross-sections, the first in the destructive and the second in the regenerative period. These fluctuations in cell dimensions do not occur around but above the control level, attaining the latter level only at the minimum (4th day). The size of the cryptal cells of the intact intestinal epithelium is evidently close to the minimum needed for enterocyte proliferation. The considerable increase in crypt dimensions in the regenerative period (beginning from the 6th day) is not due to the larger number of cells (they are even somewhat fewer than normal) but rather to a substantial increase in cell dimensions. Thus, according to these data, on the 6th-8th day after irradiation the intestinal epithelium deviates strongly from the stationary state. The index I sub(v), where I is the mitotic index and v the cell volume, was used to evaluate the changes in the value of the material stream, connected with proliferation, to the intestinal epithelium per cryptal cell. A considerable increase was found in this stream (hypertrophy of proliferative cells) in the intestinal epithelium restored after irradiation. (author)

  12. The Xenobiotic Transporter Mdr1 Enforces T Cell Homeostasis in the Presence of Intestinal Bile Acids.

    Science.gov (United States)

    Cao, Wei; Kayama, Hisako; Chen, Mei Lan; Delmas, Amber; Sun, Amy; Kim, Sang Yong; Rangarajan, Erumbi S; McKevitt, Kelly; Beck, Amanda P; Jackson, Cody B; Crynen, Gogce; Oikonomopoulos, Angelos; Lacey, Precious N; Martinez, Gustavo J; Izard, Tina; Lorenz, Robin G; Rodriguez-Palacios, Alex; Cominelli, Fabio; Abreu, Maria T; Hommes, Daniel W; Koralov, Sergei B; Takeda, Kiyoshi; Sundrud, Mark S

    2017-12-19

    CD4 + T cells are tightly regulated by microbiota in the intestine, but whether intestinalcells interface with host-derived metabolites is less clear. Here, we show that CD4 + T effector (Teff) cells upregulated the xenobiotic transporter, Mdr1, in the ileum to maintain homeostasis in the presence of bile acids. Whereas wild-type Teff cells upregulated Mdr1 in the ileum, those lacking Mdr1 displayed mucosal dysfunction and induced Crohn's disease-like ileitis following transfer into Rag1 -/- hosts. Mdr1 mitigated oxidative stress and enforced homeostasis in Teff cells exposed to conjugated bile acids (CBAs), a class of liver-derived emulsifying agents that actively circulate through the ileal mucosa. Blocking ileal CBA reabsorption in transferred Rag1 -/- mice restored Mdr1-deficient Teff cell homeostasis and attenuated ileitis. Further, a subset of ileal Crohn's disease patients displayed MDR1 loss of function. Together, these results suggest that coordinated interaction between mucosal Teff cells and CBAs in the ileum regulate intestinal immune homeostasis. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Optimization of micro-fabricated porous membranes for intestinal epithelial cell culture and in vitro modeling of the human intestinal barrier

    Science.gov (United States)

    Nair Gourikutty Sajay, Bhuvanendran; Yin, Chiam Su; Ramadan, Qasem

    2017-12-01

    In vitro modeling of organs could provide a controlled platform for studying physiological events and has great potential in the field of pharmaceutical development. Here, we describe the characterization of in vitro modeling of the human intestinal barrier mimicked using silicon porous membranes as a substrate. To mimic an intestinal in vivo setup as closely as possible, a porous substrate is required in a dynamic environment for the cells to grow rather than a static setup with an impermeable surface such as a petri dish. In this study, we focus on the detailed characterization of Caco-2 cells cultured on a silicon membrane with different pore sizes as well as the effect of dynamic fluid flow on the model. The porous silicon membrane together with continuous perfusion of liquid applying shear stress on the cells enhances the differentiation of polarized cells by providing access to the both their basal and apical surfaces. Membranes with pore sizes of 0.5-3 µm were used and a shear stress of ~0.03 dyne cm-2 was created by applying a low flow rate of 20 nl s-1. By providing these optimized conditions, cells were able to differentiate with columnar morphology, which developed microvilli structures on their apical side and tight junctions between adjacent cells like those in a healthy human intestinal barrier. In this setup, it is possible to study the important cellular functions of the intestine such as transport, absorption and secretion, and thus this model has great potential in drug screening.

  14. Isolation and Flow Cytometry Analysis of Innate Lymphoid Cells from the Intestinal Lamina Propria.

    Science.gov (United States)

    Gronke, Konrad; Kofoed-Nielsen, Michael; Diefenbach, Andreas

    2017-01-01

    The intestinal mucosa constitutes the biggest surface area of the body. It is constantly challenged by bacteria, commensal and pathogenic, protozoa, and food-derived irritants. In order to maintain homeostasis, a complex network of signaling circuits has evolved that includes contributions of immune cells. In recent years a subset of lymphocytes, which belong to the innate immune system, has caught particular attention. These so-called innate lymphoid cells (ILC) reside within the lamina propria of the small and large intestines and rapidly respond to environmental challenges. They provide immunity to various types of infections but may also contribute to organ homeostasis as they produce factors acting on epithelial cells thereby enhancing barrier integrity. Here, we describe how these cells can be isolated from their environment and provide an in-depth protocol how to visualize the various ILC subsets by flow cytometry.

  15. MAP kinase pathways and calcitonin influence CD44 alternate isoform expression in prostate cancer cells

    International Nuclear Information System (INIS)

    Robbins, Eric W; Travanty, Emily A; Yang, Kui; Iczkowski, Kenneth A

    2008-01-01

    Dysregulated expression and splicing of cell adhesion marker CD44 is found in many types of cancer. In prostate cancer (PC) specifically, the standard isoform (CD44s) has been found to be downregulated compared with benign tissue whereas predominant variant isoform CD44v7-10 is upregulated. Mitogen-activated protein kinase pathways and paracrine calcitonin are two common factors linked to dysregulated expression and splicing of CD44 in cancer. Calcitonin has been found to increase proliferation and invasion in PC acting through the protein kinase A pathway. In androgen-independent PC with known high CD44v7-10 expression, CD44 total and CD44v7-10 RNA or protein were assessed in response to exogenous and endogenous calcitonin and to inhibitors of protein kinase A, MEK, JNK, or p38 kinase. Benign cells and calcitonin receptor-negative PC cells were also tested. MEK or p38 but not JNK reduced CD44 total RNA by 40%–65% in cancer and benign cells. Inhibition of protein kinase A reduced CD44 total and v7-10 protein expression. In calcitonin receptor-positive cells only, calcitonin increased CD44 variant RNA and protein by 3 h and persisting to 48 h, apparently dependent on an uninhibited p38 pathway. Cells with constitutive CT expression showed an increase in CD44v7-10 mRNA but a decrease in CD44 total RNA. The MEK pathway increases CD44 RNA, while calcitonin, acting through the protein kinase A and p38 pathway, facilitates variant splicing. These findings could be used in the formulation of therapeutic methods for PC targeting CD44 alternate splicing

  16. Cell-permeable intrinsic cellular inhibitors of apoptosis protect and rescue intestinal epithelial cells from radiation-induced cell death

    International Nuclear Information System (INIS)

    Matsuzaki-Horibuchi, Shiori; Yasuda, Takeshi; Sakaguchi, Nagako; Yamaguchi, Yoshihiro; Akashi, Makoto

    2015-01-01

    One of the important mechanisms for gastrointestinal (GI) injury following high-dose radiation exposure is apoptosis of epithelial cells. X-linked inhibitor of apoptosis (XIAP) and cellular IAP2 (cIAP2) are intrinsic cellular inhibitors of apoptosis. In order to study the effects of exogenously added IAPs on apoptosis in intestinal epithelial cells, we constructed bacterial expression plasmids containing genes of XIAP (full-length, BIR2 domain and BIR3-RING domain with and without mutations of auto-ubiquitylation sites) and cIAP2 proteins fused to a protein-transduction domain (PTD) derived from HIV-1 Tat protein (TAT) and purified these cell-permeable recombinant proteins. When the TAT-conjugated IAPs were added to rat intestinal epithelial cells IEC6, these proteins were effectively delivered into the cells and inhibited apoptosis, even when added after irradiation. Our results suggest that PTD-mediated delivery of IAPs may have clinical potential, not only for radioprotection but also for rescuing the GI system from radiation injuries. (author)

  17. A Refined Culture System for Human Induced Pluripotent Stem Cell-Derived Intestinal Epithelial Organoids

    Directory of Open Access Journals (Sweden)

    Yu Takahashi

    2018-01-01

    Full Text Available Gut epithelial organoids are routinely used to investigate intestinal biology; however, current culture methods are not amenable to genetic manipulation, and it is difficult to generate sufficient numbers for high-throughput studies. Here, we present an improved culture system of human induced pluripotent stem cell (iPSC-derived intestinal organoids involving four methodological advances. (1 We adopted a lentiviral vector to readily establish and optimize conditioned medium for human intestinal organoid culture. (2 We obtained intestinal organoids from human iPSCs more efficiently by supplementing WNT3A and fibroblast growth factor 2 to induce differentiation into definitive endoderm. (3 Using 2D culture, followed by re-establishment of organoids, we achieved an efficient transduction of exogenous genes in organoids. (4 We investigated suspension organoid culture without scaffolds for easier harvesting and assays. These techniques enable us to develop, maintain, and expand intestinal organoids readily and quickly at low cost, facilitating high-throughput screening of pathogenic factors and candidate treatments for gastrointestinal diseases.

  18. Activation-induced cell death of dendritic cells is dependent on sphingosine kinase 1

    Directory of Open Access Journals (Sweden)

    Anja eSchwiebs

    2016-04-01

    Full Text Available Sphingosine 1-phosphate (S1P is an immune modulatory lipid mediator and has been implicated in numerous pathophysiological processes. S1P is produced by sphingosine kinase 1 (Sphk1 and Sphk2. Dendritic cells (DCs are central for the direction of immune responses and crucially involved in autoimmunity and cancerogenesis. In this study we examined the function and survival of bone marrow-derived DCs under long-term inflammatory stimulation. We observed that differentiated cells undergo activation-induced cell death upon LPS stimulation with an increased metabolic activity shortly after stimulation, followed by a rapid activation of caspase 3 and subsequent augmented apoptosis. Importantly, we highlight a profound role of Sphk1 in secretion of inflammatory cytokines and survival of dendritic cells that might be mediated by a change in sphingolipid levels as well as by a change in STAT3 expression. Cell growth during differentiation of Sphk1-deficient cells treated with the functional S1P receptor antagonist FTYP was reduced. Importantly, in dendritic cells we did not observe a compensatory regulation of Sphk2 mRNA in Sphk1-deficient cells. Instead, we discovered a massive increase in Sphk1 mRNA concentration upon long-term stimulation with LPS in wild type cells that might function as an attempt to rescue from inflammation-caused cell death. Taken together, in this investigation we describe details of a crucial involvement of sphingolipids and Sphk1 in activation-induced cell death during long-term immunogenic activity of DCs that might play an important role in autoimmunity and might explain the differences in immune response observed in in vivo studies of Sphk1 modulation.

  19. Cdc42 and Rab8a are critical for intestinal stem cell division, survival, and differentiation in mice

    DEFF Research Database (Denmark)

    Sakamori, Ryotaro; Das, Soumyashree; Yu, Shiyan

    2012-01-01

    The constant self renewal and differentiation of adult intestinal stem cells maintains a functional intestinal mucosa for a lifetime. However, the molecular mechanisms that regulate intestinal stem cell division and epithelial homeostasis are largely undefined. We report here that the small GTPases...... reminiscent of human microvillus inclusion disease (MVID), a devastating congenital intestinal disorder that results in severe nutrient deprivation. Further analysis revealed that Cdc42-deficient stem cells had cell division defects, reduced capacity for clonal expansion and differentiation into Paneth cells...... suggest that defects of the stem cell niche can cause MVID. This hypothesis represents a conceptual departure from the conventional view of this disease, which has focused on the affected enterocytes, and suggests stem cell-based approaches could be beneficial to infants with this often lethal condition....

  20. Steroid hormones as regulators of the proliferative activity of normal and neoplastic intestinal epithelial cells (review).

    Science.gov (United States)

    Tutton, P J; Barkla, D H

    1988-01-01

    Glucocorticoid and mineralocorticoid receptors are present in normal epithelial cells of both the small and large intestine and there have also been contentious reports of androgen, oestrogen and progesterone receptors in the epithelium of the normal large intestine. The majority of reports suggest that stimulation of the intestinal glucocorticoid receptors results in increased proliferation of epithelial cells in the small bowel, as does stimulation of androgen receptors and possibly mineralocorticoid receptors. The proliferative response of the normal intestine to oestrogens is difficult to evaluate and that to progestigens appears not to have been reported. Epidemiological studies reveal a higher incidence of bowel cancer in premenopausal women than in men of the same age and yet there is a lower incidence of these tumors in women of higher parity. These findings have been atributted to a variety of non-epithelial gender characteristic such as differences in bile metabolism, colonic bacterial and fecal transit times. In experimental animals, androgens have also been shown to influence carcinogenesis and this could well be attributed to changes in food intake etc. However, many studies have now revealed steroid hormone receptors on colorectal tumor cells and thus a direct effect of the steroid hormones on the epithelium during and after malignant transformation must now be considered.

  1. Relevance of mast cell-nerve interactions in intestinal nociception

    NARCIS (Netherlands)

    van Diest, Sophie A.; Stanisor, Oana I.; Boeckxstaens, Guy E.; de Jonge, Wouter J.; van den Wijngaard, René M.

    2012-01-01

    Cross-talk between the immune- and nervous-system is considered an important biological process in health and disease. Because mast cells are often strategically placed between nerves and surrounding (immune)cells they may function as important intermediate cells. This review summarizes the current

  2. Control mechanisms of cell proliferation in intestinal epithelium

    NARCIS (Netherlands)

    R.P.C. Rijke (Rudy)

    1977-01-01

    textabstractIn the adult organism some organs and tissues still contain proliferating and differentiating cells, whereas other organs only consist of non-dividing specialized cells. On the basis of their proliferative activity cell populations may be classified into three categories (135, 138,208).

  3. VEGF secretion during hypoxia depends on free radicals-induced Fyn kinase activity in mast cells

    International Nuclear Information System (INIS)

    Garcia-Roman, Jonathan; Ibarra-Sanchez, Alfredo; Lamas, Monica; Gonzalez Espinosa, Claudia

    2010-01-01

    Research highlights: → Bone marrow-derived mast cells (BMMCs) secrete functional VEGF but do not degranulate after Cobalt chloride-induced hypoxia. → CoCl 2 -induced VEGF secretion in mast cells occurs by a Ca 2+ -insensitive but brefeldin A and Tetanus toxin-sensitive mechanism. → Trolox and N-acetylcysteine inhibit hypoxia-induced VEGF secretion but only Trolox inhibits FcεRI-dependent anaphylactic degranulation in mast cells. → Src family kinase Fyn activation after free radical production is necessary for hypoxia-induced VEGF secretion in mast cells. -- Abstract: Mast cells (MC) have an important role in pathologic conditions such as asthma and chronic obstructive pulmonary disease (COPD), where hypoxia conduce to deleterious inflammatory response. MC contribute to hypoxia-induced angiogenesis producing factors such as vascular endothelial growth factor (VEGF), but the mechanisms behind the control of hypoxia-induced VEGF secretion in this cell type is poorly understood. We used the hypoxia-mimicking agent cobalt chloride (CoCl 2 ) to analyze VEGF secretion in murine bone marrow-derived mast cells (BMMCs). We found that CoCl 2 promotes a sustained production of functional VEGF, able to induce proliferation of endothelial cells in vitro. CoCl 2 -induced VEGF secretion was independent of calcium rise but dependent on tetanus toxin-sensitive vesicle-associated membrane proteins (VAMPs). VEGF exocytosis required free radicals formation and the activation of Src family kinases. Interestingly, an important deficiency on CoCl 2 -induced VEGF secretion was observed in Fyn kinase-deficient BMMCs. Moreover, Fyn kinase was activated by CoCl 2 in WT cells and this activation was prevented by treatment with antioxidants such as Trolox and N-acetylcysteine. Our results show that BMMCs are able to release VEGF under hypoxic conditions through a tetanus toxin-sensitive mechanism, promoted by free radicals-dependent Fyn kinase activation.

  4. VEGF secretion during hypoxia depends on free radicals-induced Fyn kinase activity in mast cells

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Roman, Jonathan; Ibarra-Sanchez, Alfredo; Lamas, Monica [Departamento de Farmacobiologia, Centro de Investigacion y de Estudios Avanzados del IPN (Cinvestav, IPN) (Mexico); Gonzalez Espinosa, Claudia, E-mail: cgonzal@cinvestav.mx [Departamento de Farmacobiologia, Centro de Investigacion y de Estudios Avanzados del IPN (Cinvestav, IPN) (Mexico)

    2010-10-15

    Research highlights: {yields} Bone marrow-derived mast cells (BMMCs) secrete functional VEGF but do not degranulate after Cobalt chloride-induced hypoxia. {yields} CoCl{sub 2}-induced VEGF secretion in mast cells occurs by a Ca{sup 2+}-insensitive but brefeldin A and Tetanus toxin-sensitive mechanism. {yields} Trolox and N-acetylcysteine inhibit hypoxia-induced VEGF secretion but only Trolox inhibits Fc{epsilon}RI-dependent anaphylactic degranulation in mast cells. {yields} Src family kinase Fyn activation after free radical production is necessary for hypoxia-induced VEGF secretion in mast cells. -- Abstract: Mast cells (MC) have an important role in pathologic conditions such as asthma and chronic obstructive pulmonary disease (COPD), where hypoxia conduce to deleterious inflammatory response. MC contribute to hypoxia-induced angiogenesis producing factors such as vascular endothelial growth factor (VEGF), but the mechanisms behind the control of hypoxia-induced VEGF secretion in this cell type is poorly understood. We used the hypoxia-mimicking agent cobalt chloride (CoCl{sub 2}) to analyze VEGF secretion in murine bone marrow-derived mast cells (BMMCs). We found that CoCl{sub 2} promotes a sustained production of functional VEGF, able to induce proliferation of endothelial cells in vitro. CoCl{sub 2}-induced VEGF secretion was independent of calcium rise but dependent on tetanus toxin-sensitive vesicle-associated membrane proteins (VAMPs). VEGF exocytosis required free radicals formation and the activation of Src family kinases. Interestingly, an important deficiency on CoCl{sub 2}-induced VEGF secretion was observed in Fyn kinase-deficient BMMCs. Moreover, Fyn kinase was activated by CoCl{sub 2} in WT cells and this activation was prevented by treatment with antioxidants such as Trolox and N-acetylcysteine. Our results show that BMMCs are able to release VEGF under hypoxic conditions through a tetanus toxin-sensitive mechanism, promoted by free radicals

  5. AMP-activated protein kinase downregulates Kv7.1 cell surface expression

    DEFF Research Database (Denmark)

    Andersen, Martin N; Krzystanek, Katarzyna; Jespersen, Thomas

    2012-01-01

    in response to polarization of the epithelial Madin-Darby canine kidney (MDCK) cell line and that this was mediated by activation of protein kinase C (PKC). In this study, the pathway downstream of PKC, which leads to internalization of Kv7.1 upon cell polarization, is elucidated. We show by confocal...... microscopy that Kv7.1 is endocytosed upon initiation of the polarization process and sent for degradation by the lysosomal pathway. The internalization could be mimicked by pharmacological activation of the AMP-activated protein kinase (AMPK) using three different AMPK activators. We demonstrate...

  6. Wnt control of stem cells and differentiation in the intestinal epithelium

    International Nuclear Information System (INIS)

    Pinto, Daniel; Clevers, Hans

    2005-01-01

    The intestinal epithelium represents a very attractive experimental model for the study of integrated key cellular processes such as proliferation and differentiation. The tissue is subjected to a rapid and perpetual self-renewal along the crypt-villus axis. Renewal requires division of multipotent stem cells, still to be morphologically identified and isolated, followed by transit amplification, and differentiation of daughter cells into specialized absorptive and secretory cells. Our understanding of the crucial role played by the Wnt/β-catenin signaling pathway in controlling the fine balance between cell proliferation and differentiation in the gut has been significantly enhanced in recent years. Mutations in some of its components irreversibly lead to carcinogenesis in humans and in mice. Here, we discuss recent advances related to the Wnt/β-catenin signaling pathway in regulating intestinal stem cells, homeostasis, and cancer. We emphasize how Wnt signaling is able to maintain a stem cell/progenitor phenotype in normal intestinal crypts, and to impose a very similar phenotype onto colorectal adenomas

  7. Polarity of fatty acid uptake and metabolism in a human intestinal cell line (CACO-2)

    International Nuclear Information System (INIS)

    Trotter, P.J.; Storch, J.

    1990-01-01

    Free fatty acids (ffa) can enter the intestinal cell via the apical (AP) or basolateral (BL) membrane. The authors are using the Caco-2 intestinal cell line to examine the polarity of ffa uptake and metabolism in the enterocyte. Cells are grown on permeable polycarbonate Transwell filters in order to obtain access to both AP and BL compartments. Differentiated Caco-2 cells form tight polarized monolayers which express small intestine-specific enzymes and are impermeable to the fluid phase marker Lucifer Yellow. Submicellar concentrations of 3 H-palmitic acid (2uM) were added to AP or BL sides of Caco-2 monolayers at 37 degrees C and cells were incubated for various times between 2 and 120 minutes. Total AP and BL uptake is similar; however, when relative membrane surface areas are accounted for, AP uptake is about 2-fold higher. The metabolism of AP and BL ffa is not significantly different: triacylglycerol and phosphatidylcholine account for most of the metabolites (32±4 and 24±2% respectively at 5 minutes). Little ffa oxidation is observed. Preincubation with albumin-bound 2-monoolein (100uM) and palmitate (50uM) increases the level of TG metabolites. The results suggest that in this cell line the uptake of AP ffa may be greater than BL ffa, but that AP (dietary) ffa and BL (plasma) ffa are metabolized similarly

  8. Indian Hedgehog Suppresses a Stromal Cell-Driven Intestinal Immune Response.

    Science.gov (United States)

    Westendorp, B Florien; Büller, Nikè V J A; Karpus, Olga N; van Dop, Willemijn A; Koster, Jan; Versteeg, Rogier; Koelink, Pim J; Snel, Clinton Y; Meisner, Sander; Roelofs, Joris J T H; Uhmann, Anja; Ver Loren van Themaat, Emiel; Heijmans, Jarom; Hahn, Heidi; Muncan, Vanesa; Wildenberg, Manon E; van den Brink, Gijs R

    2018-01-01

    Upon intestinal epithelial damage a complex wound healing response is initiated to restore epithelial integrity and defend against pathogenic invasion. Epithelium-derived Indian Hedgehog (Ihh) functions as a critical sensor in this process. Signaling occurs in a paracrine manner because the receptor for Ihh is expressed only in the mesenchyme, but the exact Hedgehog target cell has remained elusive. The aim of this study was to elucidate further the nature of this target cell in the context of intestinal inflammation. Hedgehog activity was modulated genetically in both cell type-specific and body-wide models and the resulting animals were analyzed for gene expression profiles and sensitivity for dextran sodium sulfate (DSS) colitis. To characterize the Hedgehog target cell, Gli1-CreERT2-Rosa26-ZsGreen animals were generated, which express ZsGreen in all Hedgehog-responsive cells. These cells were characterized using flow cytometry and immunofluorescence. Loss of Indian Hedgehog from the intestinal epithelium resulted in a rapid increase in expression of inflammation-related genes, accompanied by increased influx of immune cells. Animals with epithelium-specific deletion of Ihh or lacking the Hedgehog receptor Smoothened from Hedgehog target cells were more sensitive to DSS colitis. In contrast, specific deletion of Smoothened in the myeloid compartment did not alter the response to DSS. This suggests that Hedgehog signaling does not repress intestinal immunity through an effect on myeloid cells. Indeed, we found that Hedgehog-responsive cells expressed gp38, smooth muscle actin, and desmin, indicating a fibroblastic nature. Ihh signaling inhibited expression of C-X-C motif chemokine ligand 12 (CXCL12) in fibroblasts in vitro and in vivo, thereby impairing the recruitment of immune cells. We show that epithelium-derived Indian Hedgehog signals exclusively to fibroblasts in the intestine. Loss of Ihh leads to a rapid immune response with up-regulation of fibroblast

  9. Osteopontin attenuates acute gastrointestinal graft-versus-host disease by preventing apoptosis of intestinal epithelial cells

    International Nuclear Information System (INIS)

    Kawakami, Kentaro; Minami, Naoki; Matsuura, Minoru; Iida, Tomoya; Toyonaga, Takahiko; Nagaishi, Kanna; Arimura, Yoshiaki; Fujimiya, Mineko; Uede, Toshimitsu; Nakase, Hiroshi

    2017-01-01

    Background and aims: Acute graft-versus-host disease (GVHD) is a major complication after allogeneic hematopoietic stem cell transplantation, which often targets gastrointestinal (GI) tract. Osteopontin (OPN) plays an important physiological role in the efficient development of Th1 immune responses and cell survival by inhibiting apoptosis. The role of OPN in acute GI-GVHD is poorly understood. In the present study, we investigated the role of OPN in donor T cells in the pathogenicity of acute GI-GVHD. Methods: OPN knockout (KO) mice and C57BL/6 (B6) mice were used as donors, and (C57BL/6 × DBA/2) F1 (BDF1) mice were used as allograft recipients. Mice with acute GI-GVHD were divided into three groups: the control group (BDF1→BDF1), B6 group (B6→BDF1), and OPN-KO group (OPN-KO→BDF1). Bone marrow cells and spleen cells from donors were transplanted to lethally irradiated recipients. Clinical GVHD scores were assessed daily. Recipients were euthanized on day 7 after transplantation, and colons and small intestines were collected for various analyses. Results: The clinical GVHD score in the OPN-KO group was significantly increased compared with the B6 and control groups. We observed a difference in the severity of colonic GVHD between the OPN-KO group and B6 group, but not small intestinal-GVHD between these groups. Interferon-γ, Tumor necrosis factor-α, Interleukin-17A, and Interleukin-18 gene expression in the OPN-KO group was differed between the colon and small intestine. Flow cytometric analysis revealed that the fluorescence intensity of splenic and colonic CD8 T cells expressing Fas Ligand was increased in the OPN-KO group compared with the B6 group. Conclusion: We demonstrated that the importance of OPN in T cells in the onset of acute GI-GVHD involves regulating apoptosis of the intestinal cell via the Fas-Fas Ligand pathway. - Highlights: • A lack of osteopontin in donor cells exacerbated clinical gastrointestinal GVHD. • Donor cells lacking

  10. Enteral peptide formulas inhibit radiation induced enteritis and apoptosis in intestinal epithelial cells and suppress the expression and function of Alzheimer's and cell division control gene products

    International Nuclear Information System (INIS)

    Cope, F.O.; Issinger, O.G.; McArdle, A.H.; Shapiro, J.; Tomei, L.D.

    1991-01-01

    Studies have shown that patients receiving enteral peptide formulas prior to irradiation have a significantly reduced incidence of enteritis and express a profound increase in intestinal cellularity. Two conceptual approaches were taken to describe this response. First was the evaluation in changes in programmed intestinal cell death and secondly the evaluation of a gene product controlling cell division cycling. This study provided a relationship between the ratio of cell death to cell formulations. The results indicate that in the canine and murine models, irradiation induces expression of the Alzheimer's gene in intestinal crypt cells, while the incidence of apoptosis in apical cells is significantly increased. The use of peptide enteral formulations suppresses the expression of the Alzheimer's gene in crypt cells, while apoptosis is eliminated in the apical cells of the intestine. Concomitantly, enteral peptide formulations suppress the function of the CK-II gene product in the basal and baso-lateral cells of the intestine. These data indicate that although the mitotic index is significantly reduced in enterocytes, this phenomenon alone is not sufficient to account for the peptide-induced radio-resistance of the intestine. The data also indicate a significant reduction of normal apoptosis in the upper lateral and apical cells of the intestinal villi. Thus, the ratio of cell death to cell replacement is significantly decreased resulting in an increase in villus height and hypertrophy of the apical villus cells. Thus, peptide solutions should be considered as an adjunct treatment both in radio- and chemotherapy

  11. Immunity and Tolerance Induced by Intestinal Mucosal Dendritic Cells

    Directory of Open Access Journals (Sweden)

    Julio Aliberti

    2016-01-01

    Full Text Available Dendritic cells present in the digestive tract are constantly exposed to environmental antigens, commensal flora, and invading pathogens. Under steady-state conditions, these cells have high tolerogenic potential, triggering differentiation of regulatory T cells to protect the host from unwanted proinflammatory immune responses to innocuous antigens or commensals. On the other hand, these cells must discriminate between commensal flora and invading pathogens and mount powerful immune response against pathogens. A potential result of unbalanced tolerogenic versus proinflammatory responses mediated by dendritic cells is associated with chronic inflammatory conditions, such as Crohn’s disease, ulcerative colitis, food allergies, and celiac disease. Herein, we review the dendritic cell population involved in mediating tolerance and immunity in mucosal surfaces, the progress in unveiling their development in vivo, and factors that can influence their functions.

  12. Identification of Mediator Kinase Substrates in Human Cells using Cortistatin A and Quantitative Phosphoproteomics.

    Science.gov (United States)

    Poss, Zachary C; Ebmeier, Christopher C; Odell, Aaron T; Tangpeerachaikul, Anupong; Lee, Thomas; Pelish, Henry E; Shair, Matthew D; Dowell, Robin D; Old, William M; Taatjes, Dylan J

    2016-04-12

    Cortistatin A (CA) is a highly selective inhibitor of the Mediator kinases CDK8 and CDK19. Using CA, we now report a large-scale identification of Mediator kinase substrates in human cells (HCT116). We identified over 16,000 quantified phosphosites including 78 high-confidence Mediator kinase targets within 64 proteins, including DNA-binding transcription factors and proteins associated with chromatin, DNA repair, and RNA polymerase II. Although RNA-seq data correlated with Mediator kinase targets, the effects of CA on gene expression were limited and distinct from CDK8 or CDK19 knockdown. Quantitative proteome analyses, tracking around 7,000 proteins across six time points (0-24 hr), revealed that CA selectively affected pathways implicated in inflammation, growth, and metabolic regulation. Contrary to expectations, increased turnover of Mediator kinase targets was not generally observed. Collectively, these data support Mediator kinases as regulators of chromatin and RNA polymerase II activity and suggest their roles extend beyond transcription to metabolism and DNA repair. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  13. MET Signaling Mediates Intestinal Crypt-Villus Development, Regeneration, and Adenoma Formation and Is Promoted by Stem Cell CD44 Isoforms.

    Science.gov (United States)

    Joosten, Sander P J; Zeilstra, Jurrit; van Andel, Harmen; Mijnals, R Clinton; Zaunbrecher, Joost; Duivenvoorden, Annet A M; van de Wetering, Marc; Clevers, Hans; Spaargaren, Marcel; Pals, Steven T

    2017-10-01

    Resistance of metastatic human colorectal cancer cells to drugs that block epidermal growth factor (EGF) receptor signaling could be caused by aberrant activity of other receptor tyrosine kinases, activating overlapping signaling pathways. One of these receptor tyrosine kinases could be MET, the receptor for hepatocyte growth factor (HGF). We investigated how MET signaling, and its interaction with CD44 (a putative MET coreceptor regulated by Wnt signaling and highly expressed by intestinal stem cells [ISCs] and adenomas) affects intestinal homeostasis, regeneration, and adenoma formation in mini-gut organoids and mice. We established organoid cultures from ISCs stimulated with HGF or EGF and assessed intestinal differentiation by immunohistochemistry. Mice with total epithelial disruption of MET (Ah Cre /Met fl/fl /LacZ) or ISC-specific disruption of MET (Lgr5 Creert2 /Met fl/fl /LacZ) and control mice (Ah Cre /Met +/+ /LacZ, Lgr5 Creert2 /Met +/+ /LacZ) were exposed to 10 Gy total body irradiation; intestinal tissues were collected, and homeostasis and regeneration were assessed by immunohistochemistry. We investigated adenoma organoid expansion stimulated by HGF or EGF using adenomas derived from Lgr5 Creert2 /Met fl/fl /Apc fl/fl and Lgr5 Creert2 /Met +/+ /Apc fl/fl mice. The same mice were evaluated for adenoma prevalence and size. We also quantified adenomas in Ah Cre /Met fl/fl /Apc fl/+ mice compared with Ah Cre /Met +/+ /Apc fl/+ control mice. We studied expansion of organoids generated from crypts and adenomas, stimulated by HGF or EGF, that were derived from mice expressing different CD44 splice variants (Cd44 +/+ , Cd44 -/- , Cd44 s/s , or Cd44 v4-10/v4-10 mice). Crypts incubated with EGF or HGF expanded into self-organizing mini-guts with similar levels of efficacy and contained all differentiated cell lineages. MET-deficient mice did not have defects in intestinal homeostasis. Total body irradiation reduced numbers of proliferating crypts in Ah Cre

  14. Influence of adhesion and bacteriocin production by Lactobacillus salivarius on the intestinal epithelial cell transcriptional response.

    Science.gov (United States)

    O'Callaghan, John; Buttó, Ludovica F; MacSharry, John; Nally, Kenneth; O'Toole, Paul W

    2012-08-01

    Lactobacillus salivarius strain UCC118 is a human intestinal isolate that has been extensively studied for its potential probiotic effects in human and animal models. The objective of this study was to determine the effect of L. salivarius UCC118 on gene expression responses in the Caco-2 cell line to improve understanding of how the strain might modulate intestinal epithelial cell phenotypes. Exposure of Caco-2 cells to UCC118 led to the induction of several human genes (TNFAIP3, NFKBIA, and BIRC3) that are negative regulators of inflammatory signaling pathways. Induction of chemokines (CCL20, CXCL-1, and CXCL-2) with antimicrobial functions was also observed. Disruption of the UCC118 sortase gene srtA causes reduced bacterial adhesion to epithelial cells. Transcription of three mucin genes was reduced significantly when Caco-2 cells were stimulated with the ΔsrtA derivative of UCC118 compared to cells stimulated with the wild type, but there was no significant change in the transcription levels of the anti-inflammatory genes. UCC118 genes that were significantly upregulated upon exposure to Caco-2 cells were identified by bacterial genome microarray and consisted primarily of two groups of genes connected with purine metabolism and the operon for synthesis of the Abp118 bacteriocin. Following incubation with Caco-2 cells, the bacteriocin synthesis genes were transcribed at higher levels in the wild type than in the ΔsrtA derivative. These data indicate that L. salivarius UCC118 influences epithelial cells both through modulation of the inflammatory response and by modulation of intestinal cell mucin production. Sortase-anchored cell surface proteins of L. salivarius UCC118 have a central role in promoting the interaction between the bacterium and epithelial cells.

  15. Hes1-deficient mice show precocious differentiation of Paneth cells in the small intestine

    International Nuclear Information System (INIS)

    Suzuki, Katsumasa; Fukui, Hirokazu; Kayahara, Takahisa; Sawada, Mitsutaka; Seno, Hiroshi; Hiai, Hiroshi; Kageyama, Ryoichiro; Okano, Hideyuki; Chiba, Tsutomu

    2005-01-01

    We have previously shown that Hes1 is expressed both in putative epithelial stem cells just above Paneth cells and in the crypt base columnar cells between Paneth cells, while Hes1 is completely absent in Paneth cells. This study was undertaken to clarify the role of Hes1 in Paneth cell differentiation, using Hes1-knockout (KO) newborn (P0) mice. Electron microscopy revealed premature appearance of distinct cells containing cytoplasmic granules in the intervillous region in Hes1-KO P0 mice, whereas those cells were absent in wild-type (WT) P0 mice. In Hes1-KO P0 mice, the gene expressions of cryptdins, exclusively present in Paneth cells, were all enhanced compared with WT P0 mice. Immunohistochemistry demonstrated increased number of both lysozyme-positive and cryptdin-4-positive cells in the small intestinal epithelium of Hes1-KO P0 mice as compared to WT P0 mice. Thus, Hes1 appears to have an inhibitory role in Paneth cell differentiation in the small intestine

  16. AMP-activated kinase mediates adipose stem cell-stimulated neuritogenesis of PC12 cells.

    Science.gov (United States)

    Tan, B; Luan, Z; Wei, X; He, Y; Wei, G; Johnstone, B H; Farlow, M; Du, Y

    2011-05-05

    Adipose tissue stroma contains a population of mesenchymal stem cells, which support repair of damaged tissues through the protective effects of secreted trophic factors. Neurotrophic factors, including nerve growth factor (NGF) have been identified in media collected from cultured adipose-derived stem cells (ASC). We previously demonstrated that administration of cell-free ASC conditioned medium (ASC-CM) at 24 h after injury reduced lesion volume and promoted functional recovery in a rat model of neonatal brain hypoxic-ischemic (HI) injury. The timing of administration well after the peak in neural cell apoptosis in the affected region suggests that regeneration of lost neurons is promoted by factors in ASC-CM. In this study, we determined which of the factors in ASC-CM could induce neurogenesis by testing the ability of the mixture, either whole or after inactivating specific components, to stimulate neurite outgrowth in vitro using the neurogenic cell line PC12. Neuritogenesis in PC12 cells treated with ASC-CM was observed at a level comparable to that observed with purified recombinant NGF. It was observed that NGF in ASC-CM was mainly responsible for inducing PC12 cell neuritogenesis. Interestingly, both ASC-CM and NGF induced PC12 cell neuritogenesis through activation of the AMP-activated kinase (AMPK) pathway which is the central protein involved in controlling many critical functions in response to changes in the cellular energy status. Pharmacological and genetic inhibition of AMPK activity greatly reduced neuritogenesis in PC12 cells. These results suggest that, in addition to possessing neuroprotective properties, ASC-CM mediates repair of damaged tissues through inducing neuronal differentiation via NGF-induced AMPK activation. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

  17. Saccharomyces boulardii improves intestinal cell restitution through activation of the α2β1 integrin collagen receptor.

    Directory of Open Access Journals (Sweden)

    Alexandra Canonici

    Full Text Available Intestinal epithelial cell damage is frequently seen in the mucosal lesions of inflammatory bowel diseases such as ulcerative colitis or Crohn's disease. Complete remission of these diseases requires both the cessation of inflammation and the migration of enterocytes to repair the damaged epithelium. Lyophilized Saccharomyces boulardii (Sb, Biocodex is a nonpathogenic yeast widely used as a therapeutic agent for the treatment and prevention of diarrhea and other gastrointestinal disorders. In this study, we determined whether Sb could accelerate enterocyte migration. Cell migration was determined in Sb force-fed C57BL6J mice and in an in vitro wound model. The impact on α2β1 integrin activity was assessed using adhesion assays and the analysis of α2β1 mediated signaling pathways both in vitro and in vivo. We demonstrated that Sb secretes compounds that enhance the migration of enterocytes independently of cell proliferation. This enhanced migration was associated with the ability of Sb to favor cell-extracellular matrix interaction. Indeed, the yeast activates α2β1 integrin collagen receptors. This leads to an increase in tyrosine phosphorylation of cytoplasmic molecules, including focal adhesion kinase and paxillin, involved in the integrin signaling pathway. These changes are associated with the reorganization of focal adhesion structures. In conclusion Sb secretes motogenic factors that enhance cell restitution through the dynamic regulation of α2β1 integrin activity. This could be of major importance in the development of novel therapies targeting diseases characterized by severe mucosal injury, such as inflammatory and infectious bowel diseases.

  18. HIC1 links retinoic acid signalling to group 3 innate lymphoid cell-dependent regulation of intestinal immunity and homeostasis

    Science.gov (United States)

    Antignano, Frann; Korinek, Vladimir; Underhill, T. Michael

    2018-01-01

    The intestinal immune system must be able to respond to a wide variety of infectious organisms while maintaining tolerance to non-pathogenic microbes and food antigens. The Vitamin A metabolite all-trans-retinoic acid (atRA) has been implicated in the regulation of this balance, partially by regulating innate lymphoid cell (ILC) responses in the intestine. However, the molecular mechanisms of atRA-dependent intestinal immunity and homeostasis remain elusive. Here we define a role for the transcriptional repressor Hypermethylated in cancer 1 (HIC1, ZBTB29) in the regulation of ILC responses in the intestine. Intestinal ILCs express HIC1 in a vitamin A-dependent manner. In the absence of HIC1, group 3 ILCs (ILC3s) that produce IL-22 are lost, resulting in increased susceptibility to infection with the bacterial pathogen Citrobacter rodentium. Thus, atRA-dependent expression of HIC1 in ILC3s regulates intestinal homeostasis and protective immunity. PMID:29470558

  19. Stress responsive miR-31 is a major modulator of mouse intestinal stem cells during regeneration and tumorigenesis.

    Science.gov (United States)

    Tian, Yuhua; Ma, Xianghui; Lv, Cong; Sheng, Xiaole; Li, Xiang; Zhao, Ran; Song, Yongli; Andl, Thomas; Plikus, Maksim V; Sun, Jinyue; Ren, Fazheng; Shuai, Jianwei; Lengner, Christopher J; Cui, Wei; Yu, Zhengquan

    2017-09-05

    Intestinal regeneration and tumorigenesis are believed to be driven by intestinal stem cells (ISCs). Elucidating mechanisms underlying ISC activation during regeneration and tumorigenesis can help uncover the underlying principles of intestinal homeostasis and disease including colorectal cancer. Here we show that miR-31 drives ISC proliferation, and protects ISCs against apoptosis, both during homeostasis and regeneration in response to ionizing radiation injury. Furthermore, miR-31 has oncogenic properties, promoting intestinal tumorigenesis. Mechanistically, miR-31 acts to balance input from Wnt, BMP, TGFβ signals to coordinate control of intestinal homeostasis, regeneration and tumorigenesis. We further find that miR-31 is regulated by the STAT3 signaling pathway in response to radiation injury. These findings identify miR-31 as a critical modulator of ISC biology, and a potential therapeutic target for a broad range of intestinal regenerative disorders and cancers.

  20. Stem-cell-specific endocytic degradation defects lead to intestinal dysplasia in Drosophila

    Directory of Open Access Journals (Sweden)

    Péter Nagy

    2016-05-01

    Full Text Available UV radiation resistance-associated gene (UVRAG is a tumor suppressor involved in autophagy, endocytosis and DNA damage repair, but how its loss contributes to colorectal cancer is poorly understood. Here, we show that UVRAG deficiency in Drosophila intestinal stem cells leads to uncontrolled proliferation and impaired differentiation without preventing autophagy. As a result, affected animals suffer from gut dysfunction and short lifespan. Dysplasia upon loss of UVRAG is characterized by the accumulation of endocytosed ligands and sustained activation of STAT and JNK signaling, and attenuation of these pathways suppresses stem cell hyperproliferation. Importantly, the inhibition of early (dynamin-dependent or late (Rab7-dependent steps of endocytosis in intestinal stem cells also induces hyperproliferation and dysplasia. Our data raise the possibility that endocytic, but not autophagic, defects contribute to UVRAG-deficient colorectal cancer development in humans.

  1. Human Intestinal Cells Modulate Conjugational Transfer of Multidrug Resistance Plasmids between Clinical Escherichia coli Isolates

    DEFF Research Database (Denmark)

    Machado, Ana Manuel; Sommer, Morten

    2014-01-01

    Bacterial conjugation in the human gut microbiota is believed to play a major role in the dissemination of antibiotic resistance genes and virulence plasmids. However, the modulation of bacterial conjugation by the human host remains poorly understood and there is a need for controlled systems...... to study this process. We established an in vitro co-culture system to study the interaction between human intestinal cells and bacteria. We show that the conjugation efficiency of a plasmid encoding an extended spectrum beta-lactamase is reduced when clinical isolates of Escherichia coli are co...... of the intestinal cells exposed to bacteria leading to a two-fold reduction in conjugation efficiency. These results show that human gut epithelial cells can modulate bacterial conjugation and may have relevance to gene exchange in the gut....

  2. Effect of an inhibitor of noradrenaline uptake, desipramine, on cell proliferation in the intestinal crypt epithelium.

    Science.gov (United States)

    Tutton, P J; Barkla, D H

    1989-01-01

    The intestinal mucosa receives an adrenergic innervation for which there is no commonly accepted function. However, in recent years, cell kinetic studies have raised the possibility that this innervation may be an important regulator of crypt cell proliferation. The effects of noradrenaline released from adrenergic nerves is terminated principally by re-uptake of the amine into the nerve and this process can be inhibited by the antidepressant drug, desipramine. In this report desipramine is shown to accelerate crypt cell proliferation in intact, but not in chemically sympathectomized rats, thus adding support to the notion that regulation of crypt cell division is an important function of the sympathetic nervous system.

  3. PAI-1-dependent endothelial cell death determines severity of radiation-induced intestinal injury.

    Directory of Open Access Journals (Sweden)

    Rym Abderrahmani

    Full Text Available Normal tissue toxicity still remains a dose-limiting factor in clinical radiation therapy. Recently, plasminogen activator inhibitor type 1 (SERPINE1/PAI-1 was reported as an essential mediator of late radiation-induced intestinal injury. However, it is not clear whether PAI-1 plays a role in acute radiation-induced intestinal damage and we hypothesized that PAI-1 may play a role in the endothelium radiosensitivity. In vivo, in a model of radiation enteropathy in PAI-1 -/- mice, apoptosis of radiosensitive compartments, epithelial and microvascular endothelium was quantified. In vitro, the role of PAI-1 in the radiation-induced endothelial cells (ECs death was investigated. The level of apoptotic ECs is lower in PAI-1 -/- compared with Wt mice after irradiation. This is associated with a conserved microvascular density and consequently with a better mucosal integrity in PAI-1 -/- mice. In vitro, irradiation rapidly stimulates PAI-1 expression in ECs and radiation sensitivity is increased in ECs that stably overexpress PAI-1, whereas PAI-1 knockdown increases EC survival after irradiation. Moreover, ECs prepared from PAI-1 -/- mice are more resistant to radiation-induced cell death than Wt ECs and this is associated with activation of the Akt pathway. This study demonstrates that PAI-1 plays a key role in radiation-induced EC death in the intestine and suggests that this contributes strongly to the progression of radiation-induced intestinal injury.

  4. Intestinal mast cells in gut inflammation and motility disturbances

    NARCIS (Netherlands)

    de Winter, Benedicte Y.; van den Wijngaard, Rene M.; de Jonge, Wouter J.

    2012-01-01

    Mast cells may be regarded as prototypes of innate immune cells that can be controlled by neuronal mediators. Their activation has been implicated in many types of neuro-inflammatory responses, and related disturbances of gut motility, via direct or indirect mechanisms that involve several

  5. Increased chromogranin A cell density in the large intestine of patients with irritable bowel syndrome after receiving dietary guidance

    OpenAIRE

    Mazzawi, Tarek; Gundersen, Doris Irene; Hausken, Trygve; El-Salhy, Magdy

    2015-01-01

    The large intestine contains five types of endocrine cells that regulate its functions by sensing its luminal contents and releasing specific hormones. Chromogranin A (CgA) is a common marker for the gastrointestinal endocrine cells, and it is abnormal in irritable bowel syndrome (IBS) patients. Most IBS patients relate their symptoms to certain food elements. The present study investigated the effect of dietary guidance on the total endocrine cells of the large intestine as detected by CgA i...

  6. Cell Adhesion Molecule CD166/ALCAM Functions Within the Crypt to Orchestrate Murine Intestinal Stem Cell HomeostasisSummary

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    Nicholas R. Smith

    2017-05-01

    Full Text Available Background & Aims: Intestinal epithelial homeostasis is maintained by active-cycling and slow-cycling stem cells confined within an instructive crypt-based niche. Exquisite regulating of these stem cell populations along the proliferation-to-differentiation axis maintains a homeostatic balance to prevent hyperproliferation and cancer. Although recent studies focus on how secreted ligands from mesenchymal and epithelial populations regulate intestinal stem cells (ISCs, it remains unclear what role cell adhesion plays in shaping the regulatory niche. Previously we have shown that the cell adhesion molecule and cancer stem cell marker, CD166/ALCAM (activated leukocyte cell adhesion molecule, is highly expressed by both active-cycling Lgr5+ ISCs and adjacent Paneth cells within the crypt base, supporting the hypothesis that CD166 functions to mediate ISC maintenance and signal coordination. Methods: Here we tested this hypothesis by analyzing a CD166–/– mouse combined with immunohistochemical, flow cytometry, gene expression, and enteroid culture. Results: We found that animals lacking CD166 expression harbored fewer active-cycling Lgr5+ ISCs. Homeostasis was maintained by expansion of the transit-amplifying compartment and not by slow-cycling Bmi1+ ISC stimulation. Loss of active-cycling ISCs was coupled with deregulated Paneth cell homeostasis, manifested as increased numbers of immature Paneth progenitors due to decreased terminal differentiation, linked to defective Wnt signaling. CD166–/– Paneth cells expressed reduced Wnt3 ligand expression and depleted nuclear β-catenin. Conclusions: These data support a function for CD166 as an important cell adhesion molecule that shapes the signaling microenvironment by mediating ISC–niche cell interactions. Furthermore, loss of CD166 expression results in decreased ISC and Paneth cell homeostasis and an altered Wnt microenvironment. Keywords: Intestinal Stem Cell, Homeostasis

  7. The role of phosphatidylinositol 3-kinase in neural cell adhesion molecule-mediated neuronal differentiation and survival

    DEFF Research Database (Denmark)

    Ditlevsen, Dorte K; Køhler, Lene B; Pedersen, Martin Volmer

    2003-01-01

    The neural cell adhesion molecule, NCAM, is known to stimulate neurite outgrowth from primary neurones and PC12 cells presumably through signalling pathways involving the fibroblast growth factor receptor (FGFR), protein kinase A (PKA), protein kinase C (PKC), the Ras-mitogen activated protein...... kinase (MAPK) pathway and an increase in intracellular Ca2+ levels. Stimulation of neurones with the synthetic NCAM-ligand, C3, induces neurite outgrowth through signalling pathways similar to the pathways activated through physiological, homophilic NCAM-stimulation. We present here data indicating...... that phosphatidylinositol 3-kinase (PI3K) is required for NCAM-mediated neurite outgrowth from PC12-E2 cells and from cerebellar and dopaminergic neurones in primary culture, and that the thr/ser kinase Akt/protein kinase B (PKB) is phosphorylated downstream of PI3K after stimulation with C3. Moreover, we present data...

  8. Recruitment of focal adhesion kinase and paxillin to β1 integrin promotes cancer cell migration via mitogen activated protein kinase activation

    International Nuclear Information System (INIS)

    Crowe, David L; Ohannessian, Arthur

    2004-01-01

    Integrin-extracellular matrix interactions activate signaling cascades such as mitogen activated protein kinases (MAPK). Integrin binding to extracellular matrix increases tyrosine phosphorylation of focal adhesion kinase (FAK). Inhibition of FAK activity by expression of its carboxyl terminus decreases cell motility, and cells from FAK deficient mice also show reduced migration. Paxillin is a focal adhesion protein which is also phosphorylated on tyrosine. FAK recruitment of paxillin to the cell membrane correlates with Shc phosphorylation and activation of MAPK. Decreased FAK expression inhibits papilloma formation in a mouse skin carcinogenesis model. We previously demonstrated that MAPK activation was required for growth factor induced in vitro migration and invasion by human squamous cell carcinoma (SCC) lines. Adapter protein recruitment to integrin subunits was examined by co-immunoprecipitation in SCC cells attached to type IV collagen or plastic. Stable clones overexpressing FAK or paxillin were created using the lipofection technique. Modified Boyden chambers were used for invasion assays. In the present study, we showed that FAK and paxillin but not Shc are recruited to the β1 integrin cytoplasmic domain following attachment of SCC cells to type IV collagen. Overexpression of either FAK or paxillin stimulated cancer cell migration on type IV collagen and invasion through reconstituted basement membrane which was dependent on MAPK activity. We concluded that recruitment of focal adhesion kinase and paxillin to β1 integrin promoted cancer cell migration via the mitogen activated protein kinase pathway

  9. Recruitment of focal adhesion kinase and paxillin to β1 integrin promotes cancer cell migration via mitogen activated protein kinase activation

    Directory of Open Access Journals (Sweden)

    Ohannessian Arthur

    2004-05-01

    Full Text Available Abstract Background Integrin-extracellular matrix interactions activate signaling cascades such as mitogen activated protein kinases (MAPK. Integrin binding to extracellular matrix increases tyrosine phosphorylation of focal adhesion kinase (FAK. Inhibition of FAK activity by expression of its carboxyl terminus decreases cell motility, and cells from FAK deficient mice also show reduced migration. Paxillin is a focal adhesion protein which is also phosphorylated on tyrosine. FAK recruitment of paxillin to the cell membrane correlates with Shc phosphorylation and activation of MAPK. Decreased FAK expression inhibits papilloma formation in a mouse skin carcinogenesis model. We previously demonstrated that MAPK activation was required for growth factor induced in vitro migration and invasion by human squamous cell carcinoma (SCC lines. Methods Adapter protein recruitment to integrin subunits was examined by co-immunoprecipitation in SCC cells attached to type IV collagen or plastic. Stable clones overexpressing FAK or paxillin were created using the lipofection technique. Modified Boyden chambers were used for invasion assays. Results In the present study, we showed that FAK and paxillin but not Shc are recruited to the β1 integrin cytoplasmic domain following attachment of SCC cells to type IV collagen. Overexpression of either FAK or paxillin stimulated cancer cell migration on type IV collagen and invasion through reconstituted basement membrane which was dependent on MAPK activity. Conclusions We concluded that recruitment of focal adhesion kinase and paxillin to β1 integrin promoted cancer cell migration via the mitogen activated protein kinase pathway.

  10. Regulation of CD93 cell surface expression by protein kinase C isoenzymes.

    Science.gov (United States)

    Ikewaki, Nobunao; Kulski, Jerzy K; Inoko, Hidetoshi

    2006-01-01

    Human CD93, also known as complement protein 1, q subcomponent, receptor (C1qRp), is selectively expressed by cells with a myeloid lineage, endothelial cells, platelets, and microglia and was originally reported to be involved in the complement protein 1, q subcomponent (C1q)-mediated enhancement of phagocytosis. The intracellular molecular events responsible for the regulation of its expression on the cell surface, however, have not been determined. In this study, the effect of protein kinases in the regulation of CD93 expression on the cell surface of a human monocyte-like cell line (U937), a human NK-like cell line (KHYG-1), and a human umbilical vein endothelial cell line (HUV-EC-C) was investigated using four types of protein kinase inhibitors, the classical protein kinase C (cPKC) inhibitor Go6976, the novel PKC (nPKC) inhibitor Rottlerin, the protein kinase A (PKA) inhibitor H-89 and the protein tyrosine kinase (PTK) inhibitor herbimycin A at their optimum concentrations for 24 hr. CD93 expression was analyzed using flow cytometry and glutaraldehyde-fixed cellular enzyme-linked immunoassay (EIA) techniques utilizing a CD93 monoclonal antibody (mAb), mNI-11, that was originally established in our laboratory as a CD93 detection probe. The nPKC inhibitor Rottlerin strongly down-regulated CD93 expression on the U937 cells in a dose-dependent manner, whereas the other inhibitors had little or no effect. CD93 expression was down-regulated by Go6976, but not by Rottlerin, in the KHYG-1 cells and by both Rottlerin and Go6976 in the HUV-EC-C cells. The PKC stimulator, phorbol myristate acetate (PMA), strongly up-regulated CD93 expression on the cell surface of all three cell-lines and induced interleukin-8 (IL-8) production by the U937 cells and interferon-gamma (IFN-gamma) production by the KHYG-1 cells. In addition, both Go6976 and Rottlerin inhibited the up-regulation of CD93 expression induced by PMA and IL-8 or IFN-gamma production in the respective cell

  11. The fate of epithelial cells in the human large intestine.

    Science.gov (United States)

    Barkla, D H; Gibson, P R

    1999-08-01

    One hundred and forty biopsies of the colon and rectum, collected during routine colonoscopies of 51 patients aged 19 to 74 years, were examined using light microscopy and transmission and scanning electron microscopy. The results indicated that surface epithelial cells undergo apoptosis, passing through fenestrations in the basement membrane to where they enter the lamina propria and are taken up by macrophages; and it is hypothesized that apoptotic cells are carried through the fenestrations on a current of fluid. The study also found that epithelial cells positioned over the crypts are better attached and more robust than those more distant from the crypt opening; and it is further hypothesized that, after reaching the top of the crypts, some goblet cells cease secreting mucus and pass onto the surface compartment of absorptive cells. An unexpected finding was that the lower regions of the crypts commonly contain isolated necrotic colonocytes. Apoptotic cells were rarely observed in the crypt epithelium. The findings of this study support the "recycling" model of epithelial cell death in the surface compartment of the human colon.

  12. Regulation of glucose metabolism in T cells; new insight into the role of Phosphoinositide 3-kinases

    Directory of Open Access Journals (Sweden)

    David K Finlay

    2012-08-01

    Full Text Available Naïve T cells are relatively quiescent cells that only require energy to prevent atrophy and for survival and migration. However, in response to developmental or extrinsic cues T cells can engage in rapid growth and robust proliferation, produce of a range of effector molecules and migrate through peripheral tissues. To meet the significantly increased metabolic demands of these activities, T cells switch from primarily metabolizing glucose to carbon dioxide through oxidative phosphorylation to utilizing glycolysis to convert glucose to lactate (termed aerobic glycolysis. This metabolic switch allows glucose to be used as a source of carbon to generate biosynthetic precursors for the production of protein, DNA and phospholipids, and is crucial for T cells to meet metabolic demands. Phosphoinositide 3-kinases (PI3K are a family of inositol lipid kinases linked with a broad range of cellular functions in T lymphocytes that include cell growth, proliferation, metabolism, differentiation, survival and migration. Initial research described a critical role for PI3K signaling through Akt (also called Protein kinase B for the increased glucose uptake and glycolysis that accompanies T cell activation. This review article relates this original research with more recent data and discusses the evidence for and against a role for PI3K in regulating the metabolic switch to aerobic glycolysis in T cells.

  13. KCl cotransport regulation and protein kinase G in cultured vascular smooth muscle cells.

    Science.gov (United States)

    Adragna, N C; Zhang, J; Di Fulvio, M; Lincoln, T M; Lauf, P K

    2002-05-15

    K-Cl cotransport is activated by vasodilators in erythrocytes and vascular smooth muscle cells and its regulation involves putative kinase/phosphatase cascades. N-ethylmaleimide (NEM) activates the system presumably by inhibiting a protein kinase. Nitrovasodilators relax smooth muscle via cGMP-dependent activation of protein kinase G (PKG), a regulator of membrane channels and transporters. We investigated whether PKG regulates K-Cl cotransport activity or mRNA expression in normal, PKG-deficient-vector-only-transfected (PKG-) and PKG-catalytic-domain-transfected (PKG+) rat aortic smooth muscle cells. K-Cl cotransport was calculated as the Cl-dependent Rb influx, and mRNA was determined by semiquantitative RT-PCR. Baseline K-Cl cotransport was higher in PKG+ than in PKG- cells (p <0.01). At 0.5 mM, NEM stimulated K-Cl cotransport by 5-fold in PKG- but not in PKG+ cells. However, NEM was more potent although less effective to activate K-Cl cotransport in normal (passage 1-3) and PKG+ than in PKG- cells. In PKG- cells, [(dihydroindenyl) oxy] alkanoic acid (300 mM) but not furosemide (1 mM) inhibited K-Cl cotransport. Furthermore, no difference in K-Cl cotransport mRNA expression was observed between these cells. In conclusion, this study shows that manipulation of PKG expression in vascular smooth muscle cells affects K-Cl cotransport activity and its activation by NEM.

  14. Krüppel-like factor 5 is essential for proliferation and survival of mouse intestinal epithelial stem cells

    Directory of Open Access Journals (Sweden)

    Mandayam O. Nandan

    2015-01-01

    Full Text Available Krüppel-like factor 5 (KLF5 is a pro-proliferative transcription factor that is expressed in dividing epithelial cells of the intestinal crypt. Leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5 has been identified as a stem cell marker in both small intestinal and colonic epithelial cells. To determine whether KLF5 regulates proliferation of intestinal stem cells, we investigated the effects of Klf5 deletion specifically from the intestinal stem cells in adult mice. Mice with inducible intestinal stem cell-specific deletion of Klf5 (Lgr5-Klf5fl/fl were injected with tamoxifen for 5 consecutive days to induce Lgr5-driven Cre expression. Intestinal and colonic tissues were examined by immunohistochemistry at various time points up to 112 days following start of tamoxifen treatment. Klf5 is co-localized in the crypt-based columnar (CBC cells that express Lgr5. By 11 days following the start of tamoxifen treatment, Lgr5-positive crypts from which Klf5 was deleted exhibited a loss of proliferation that was accompanied by an increase in apoptosis. Beginning at 14 days following the start of tamoxifen treatment, both Klf5 expression and proliferation were re-established in the transit-amplifying epithelial cells but not in the Lgr5-positive CBC cells. By 112 days post-treatment, up to 90% of the Lgr5-positive cells from which Klf5 was deleted were lost from the intestinal crypts. These results indicate a critical role for KLF5 in the survival and maintenance of intestinal stem cells.

  15. Trophoblast cell fusion and differentiation are mediated by both the protein kinase C and a pathways.

    Directory of Open Access Journals (Sweden)

    Waka Omata

    Full Text Available The syncytiotrophoblast of the human placenta is an epithelial barrier that interacts with maternal blood and is a key for the transfer of nutrients and other solutes to the developing fetus. The syncytiotrophoblast is a true syncytium and fusion of progenitor cytotrophoblasts is the cardinal event leading to the formation of this layer. BeWo cells are often used as a surrogate for cytotrophoblasts, since they can be induced to fuse, and then express certain differentiation markers associated with trophoblast syncytialization. Dysferlin, a syncytiotrophoblast membrane repair protein, is up-regulated in BeWo cells induced to fuse by treatment with forskolin; this fusion is thought to occur through cAMP/protein kinase A-dependent mechanisms. We hypothesized that dysferlin may also be up-regulated in response to fusion through other pathways. Here, we show that BeWo cells can also be induced to fuse by treatment with an activator of protein kinase C, and that this fusion is accompanied by increased expression of dysferlin. Moreover, a dramatic synergistic increase in dysferlin expression is observed when both the protein kinase A and protein kinase C pathways are activated in BeWo cells. This synergy in fusion is also accompanied by dramatic increases in mRNA for the placental fusion proteins syncytin 1, syncytin 2, as well as dysferlin. Dysferlin, however, was shown to be dispensable for stimulus-induced BeWo cell syncytialization, since dysferlin knockdown lines fused to the same extent as control cells. The classical trophoblast differentiation marker human chorionic gonadotropin was also monitored and changes in the expression closely parallel that of dysferlin in all of the experimental conditions employed. Thus different biochemical markers of trophoblast fusion behave in concert supporting the hypothesis that activation of both protein kinase C and A pathways lead to trophoblastic differentiation.

  16. Overall survival after immunotherapy, tyrosine kinase inhibitors and surgery in treatment of metastatic renal cell cancer

    DEFF Research Database (Denmark)

    de Lichtenberg, Trine Honnens; Hermann, Gregers G.; Rorth, Mikael

    2014-01-01

    Abstract Objective. The aim of this study was to evaluate overall survival (OS) after treatment of metastatic renal cell carcinoma (mRCC) following the introduction of tyrosine kinase inhibitors (TKIs) and mammalian target of rapamycin (mTOR) inhibitors. Material and methods. One-hundred and forty...

  17. Dendritic cells sensitize TCRs through self-MHC-mediated Src family kinase activation

    Czech Academy of Sciences Publication Activity Database

    Meraner, P.; Hořejší, Václav; Wolpl, A.; Fischer, G.F.; Stingl, G.; Maurer, D.

    2007-01-01

    Roč. 178, č. 4 (2007), s. 2262-2271 ISSN 0022-1767 Institutional research plan: CEZ:AV0Z50520514 Keywords : TCR * dendritic cells * Src kinases Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 6.068, year: 2007

  18. Functional modulation of human intestinal epithelial cell responses by Bifidobacterium infantis and Lactobacillus salivarius

    Science.gov (United States)

    O'Hara, Ann M; O'Regan, Padraig; Fanning, Áine; O'Mahony, Caitlin; MacSharry, John; Lyons, Anne; Bienenstock, John; O'Mahony, Liam; Shanahan, Fergus

    2006-01-01

    Intestinal epithelial cells (IECs) and dendritic cells (DCs) play a pivotal role in antigen sampling and the maintenance of gut homeostasis. However, the interaction of commensal bacteria with the intestinal surface remains incompletely understood. Here we investigated immune cell responses to commensal and pathogenic bacteria. HT-29 human IECs were incubated with Bifidobacterium infantis 35624, Lactobacillus salivarius UCC118 or Salmonella typhimurium UK1 for varying times, or were pretreated with a probiotic for 2 hr prior to stimulation with S. typhimurium or flagellin. Gene arrays were used to examine inflammatory gene expression. Nuclear factor (NF)-κB activation, interleukin (IL)-8 secretion, pathogen adherence to IECs, and mucin-3 (MUC3) and E-cadherin gene expression were assayed by TransAM assay, enzyme-linked immunosorbent assay (ELISA), fluorescence, and real-time reverse transcriptase–polymerase chain reaction (RT-PCR), respectively. IL-10 and tumour necrosis factor (TNF)-α secretion by bacteria-treated peripheral blood-derived DCs were measured using ELISA. S. typhimurium increased expression of 36 of the 847 immune-related genes assayed, including NF-κB and IL-8. The commensal bacteria did not alter expression levels of any of the 847 genes. However, B. infantis and L. salivarius attenuated both IL-8 secretion at baseline and S. typhimurium-induced pro-inflammatory responses. B. infantis also limited flagellin-induced IL-8 protein secretion. The commensal bacteria did not increase MUC3 or E-cadherin expression, or interfere with pathogen binding to HT-29 cells, but they did stimulate IL-10 and TNF-α secretion by DCs. The data demonstrate that, although the intestinal epithelium is immunologically quiescent when it encounters B. infantis or L. salivarius, these commensal bacteria exert immunomodulatory effects on intestinal immune cells that mediate host responses to flagellin and enteric pathogens. PMID:16771855

  19. Coating with luminal gut-constituents alters adherence of nanoparticles to intestinal epithelial cells

    Directory of Open Access Journals (Sweden)

    Heike Sinnecker

    2014-12-01

    Full Text Available Background: Anthropogenic nanoparticles (NPs have found their way into many goods of everyday life. Inhalation, ingestion and skin contact are potential routes for NPs to enter the body. In particular the digestive tract with its huge absorptive surface area provides a prime gateway for NP uptake. Considering that NPs are covered by luminal gut-constituents en route through the gastrointestinal tract, we wanted to know if such modifications have an influence on the interaction between NPs and enterocytes.Results: We investigated the consequences of a treatment with various luminal gut-constituents on the adherence of nanoparticles to intestinal epithelial cells. Carboxylated polystyrene particles 20, 100 and 200 nm in size represented our anthropogenic NPs, and differentiated Caco-2 cells served as model for mature enterocytes of the small intestine. Pretreatment with the proteins BSA and casein consistently reduced the adherence of all NPs to the cultured enterocytes, while incubation of NPs with meat extract had no obvious effect on particle adherence. In contrast, contact with intestinal fluid appeared to increase the particle-cell interaction of 20 and 100 nm NPs.Conclusion: Luminal gut-constituents may both attenuate and augment the adherence of NPs to cell surfaces. These effects appear to be dependent on the particle size as well as on the type of interacting protein. While some proteins will rather passivate particles towards cell attachment, possibly by increasing colloid stability or camouflaging attachment sites, certain components of intestinal fluid are capable to modify particle surfaces in such a way that interactions with cellular surface structures result in an increased binding.

  20. Bioengineered Systems and Designer Matrices That Recapitulate the Intestinal Stem Cell Niche

    Directory of Open Access Journals (Sweden)

    Yuli Wang

    2018-01-01

    Full Text Available The relationship between intestinal stem cells (ISCs and the surrounding niche environment is complex and dynamic. Key factors localized at the base of the crypt are necessary to promote ISC self-renewal and proliferation, to ultimately provide a constant stream of differentiated cells to maintain the epithelial barrier. These factors diminish as epithelial cells divide, migrate away from the crypt base, differentiate into the postmitotic lineages, and end their life span in approximately 7 days when they are sloughed into the intestinal lumen. To facilitate the rapid and complex physiology of ISC-driven epithelial renewal, in vivo gradients of growth factors, extracellular matrix, bacterial products, gases, and stiffness are formed along the crypt-villus axis. New bioengineered tools and platforms are available to recapitulate various gradients and support the stereotypical cellular responses associated with these gradients. Many of these technologies have been paired with primary small intestinal and colonic epithelial cells to re-create select aspects of normal physiology or disease states. These biomimetic platforms are becoming increasingly sophisticated with the rapid discovery of new niche factors and gradients. These advancements are contributing to the development of high-fidelity tissue constructs for basic science applications, drug screening, and personalized medicine applications. Here, we discuss the direct and indirect evidence for many of the important gradients found in vivo and their successful application to date in bioengineered in vitro models, including organ-on-chip and microfluidic culture devices.

  1. Bmi1 regulates murine intestinal stem cell proliferation and self-renewal downstream of Notch.

    Science.gov (United States)

    López-Arribillaga, Erika; Rodilla, Verónica; Pellegrinet, Luca; Guiu, Jordi; Iglesias, Mar; Roman, Angel Carlos; Gutarra, Susana; González, Susana; Muñoz-Cánoves, Pura; Fernández-Salguero, Pedro; Radtke, Freddy; Bigas, Anna; Espinosa, Lluís

    2015-01-01

    Genetic data indicate that abrogation of Notch-Rbpj or Wnt-β-catenin pathways results in the loss of the intestinal stem cells (ISCs). However, whether the effect of Notch is direct or due to the aberrant differentiation of the transit-amplifying cells into post-mitotic goblet cells is unknown. To address this issue, we have generated composite tamoxifen-inducible intestine-specific genetic mouse models and analyzed the expression of intestinal differentiation markers. Importantly, we found that activation of β-catenin partially rescues the differentiation phenotype of Rbpj deletion mutants, but not the loss of the ISC compartment. Moreover, we identified Bmi1, which is expressed in the ISC and progenitor compartments, as a gene that is co-regulated by Notch and β-catenin. Loss of Bmi1 resulted in reduced proliferation in the ISC compartment accompanied by p16(INK4a) and p19(ARF) (splice variants of Cdkn2a) accumulation, and increased differentiation to the post-mitotic goblet cell lineage that partially mimics Notch loss-of-function defects. Finally, we provide evidence that Bmi1 contributes to ISC self-renewal. © 2015. Published by The Company of Biologists Ltd.

  2. Heparin modulates human intestinal smooth muscle (HISM) cell proliferation and matrix production

    International Nuclear Information System (INIS)

    Graham, M.; Perr, H.; Drucker, D.E.; Diegelmann, R.F.

    1986-01-01

    (HISM) cell proliferation and collagen production may play a role in the pathogenesis of intestinal stricture in Crohn's disease. The present studies were performed to evaluate the effects of heparin, a known modulator of vascular smooth muscle cells, on HISM cell proliferation and collagen production. Heparin (100 μg/ml) was added daily to HISM cell cultures for cell proliferation studies and for 24 hours at various time points during culture for collagen synthesis studies. Collagen synthesis was determined by the uptake of 3 H proline into collagenase-sensitive protein. Heparin completely inhibited cell proliferation for 7 days, after which cell numbers increased but at a slower rate than controls. Cells released from heparin inhibition demonstrated catch-up growth to control levels. Collagen production was significantly inhibited by 24 hours exposure to heparin but only at those times during culture when collagen synthesis was maximal (8 to 12 days). Non-collagen protein synthesis was inhibited by heparin at all time points during culture. Heparin through its modulation of HISM cells may play an important role in the control of the extracellular matrix of the intestinal wall

  3. Effects of the ionising radiations on the structure and the function of the intestinal epithelial cell

    International Nuclear Information System (INIS)

    Haton, C.

    2005-06-01

    The intestinal mucosa is a particularly radio-sensitive tissue and damage may occur following either accidental or therapeutic exposure. the deleterious actions of ionizing radiation are linked to the formation of sometimes overwhelming quantities of reactive oxygen species (R.O.S.). Production of R.O.S. is both direct and indirect from the secondary effects of irradiation. A better comprehension of the underlying mechanisms of injury will lead to more adapted therapeutic approaches to limit the harmful effects of irradiation. The homeostasis of the intestinal epithelium is regulated by three factors: proliferation, apoptosis and differentiation. these three factors were studied using the cell model, HT29, in order to analyze modulations of this balance after irradiation. our results, in agreement with other data, showed the establishment of mitotic delay. This arrest of proliferation was followed by apoptosis to be the major mechanism leading to cell death in this model. thus, for the first time, we have shown that irradiated intestinal epithelial cells preserve their capacity to differentiate. This indicates, although indirectly, that intestinal cells have and preserve an intrinsic capacity restore a functional epithelium. R.O.S. are considered as intermediates between the physical nature of radiations and biological responses. It seems essential to understand anti-oxidant mechanisms used by the cell for defence against the deleterious effects of R.O.S post exposure. This study of several anti-oxidant defence mechanisms of intestinal mucosa, was carried out in vivo in the mouse at different times following abdominal irradiation. We observed an early mitochondrial response in the hours following irradiation revealing this organelle as a particular target. We demonstrated a strong alteration of anti-oxidant capacity as revealed by a decrease in S.O.D.s, catalase and an increase of the G.P.X.s and M.T.s. A part of these modifications appeared to depend on an

  4. Odin (ANKS1A is a Src family kinase target in colorectal cancer cells

    Directory of Open Access Journals (Sweden)

    Feller Stephan M

    2008-10-01

    Full Text Available Abstract Background Src family kinases (SFK are implicated in the development of some colorectal cancers (CRC. One SFK member, Lck, is not detectable in normal colonic epithelium, but becomes aberrantly expressed in a subset of CRCs. Although SFK have been extensively studied in fibroblasts and different types of immune cells, their physical and functional targets in many epithelial cancers remain poorly characterised. Results 64 CRC cell lines were tested for expression of Lck. SW620 CRC cells, which express high levels of Lck and also contain high basal levels of tyrosine phosphorylated (pY proteins, were then analysed to identify novel SFK targets. Since SH2 domains of SFK are known to often bind substrates after phosphorylation by the kinase domain, the LckSH2 was compared with 14 other SH2s for suitability as affinity chromatography reagent. Mass spectrometric analyses of LckSH2-purified pY proteins subsequently identified several proteins readily known as SFK kinase substrates, including cortactin, Tom1L1 (SRCASM, GIT1, vimentin and AFAP1L2 (XB130. Additional proteins previously reported as substrates of other tyrosine kinase were also detected, including the EGF and PDGF receptor target Odin. Odin was further analysed and found to contain substantially less pY upon inhibition of SFK activity in SW620 cells, indicating that it is a formerly unknown SFK target in CRC cells. Conclusion Rapid identification of known and novel SFK targets in CRC cells is feasible with SH2 domain affinity chromatography. The elucidation of new SFK targets like Odin in epithelial cancer cells is expected to lead to novel insight into cancer cell signalling mechanisms and may also serve to indicate new biomarkers for monitoring tumor cell responses to drug treatments.

  5. A multicenter study to standardize reporting and analyses of fluorescence-activated cell-sorted murine intestinal epithelial cells

    Science.gov (United States)

    Magness, Scott T.; Puthoff, Brent J.; Crissey, Mary Ann; Dunn, James; Henning, Susan J.; Houchen, Courtney; Kaddis, John S.; Kuo, Calvin J.; Li, Linheng; Lynch, John; Martin, Martin G.; May, Randal; Niland, Joyce C.; Olack, Barbara; Qian, Dajun; Stelzner, Matthias; Swain, John R.; Wang, Fengchao; Wang, Jiafang; Wang, Xinwei; Yan, Kelley; Yu, Jian

    2013-01-01

    Fluorescence-activated cell sorting (FACS) is an essential tool for studies requiring isolation of distinct intestinal epithelial cell populations. Inconsistent or lack of reporting of the critical parameters associated with FACS methodologies has complicated interpretation, comparison, and reproduction of important findings. To address this problem a comprehensive multicenter study was designed to develop guidelines that limit experimental and data reporting variability and provide a foundation for accurate comparison of data between studies. Common methodologies and data reporting protocols for tissue dissociation, cell yield, cell viability, FACS, and postsort purity were established. Seven centers tested the standardized methods by FACS-isolating a specific crypt-based epithelial population (EpCAM+/CD44+) from murine small intestine. Genetic biomarkers for stem/progenitor (Lgr5 and Atoh 1) and differentiated cell lineages (lysozyme, mucin2, chromogranin A, and sucrase isomaltase) were interrogated in target and control populations to assess intra- and intercenter variability. Wilcoxon's rank sum test on gene expression levels showed limited intracenter variability between biological replicates. Principal component analysis demonstrated significant intercenter reproducibility among four centers. Analysis of data collected by standardized cell isolation methods and data reporting requirements readily identified methodological problems, indicating that standard reporting parameters facilitate post hoc error identification. These results indicate that the complexity of FACS isolation of target intestinal epithelial populations can be highly reproducible between biological replicates and different institutions by adherence to common cell isolation methods and FACS gating strategies. This study can be considered a foundation for continued method development and a starting point for investigators that are developing cell isolation expertise to study physiology and

  6. Kinase Gene Expression Profiling of Metastatic Clear Cell Renal Cell Carcinoma Tissue Identifies Potential New Therapeutic Targets.

    Directory of Open Access Journals (Sweden)

    Pooja Ghatalia

    Full Text Available Kinases are therapeutically actionable targets. Kinase inhibitors targeting vascular endothelial growth factor receptors (VEGFR and mammalian target of rapamycin (mTOR improve outcomes in metastatic clear cell renal cell carcinoma (ccRCC, but are not curative. Metastatic tumor tissue has not been comprehensively studied for kinase gene expression. Paired intra-patient kinase gene expression analysis in primary tumor (T, matched normal kidney (N and metastatic tumor tissue (M may assist in identifying drivers of metastasis and prioritizing therapeutic targets. We compared the expression of 519 kinase genes using NanoString in T, N and M in 35 patients to discover genes over-expressed in M compared to T and N tissue. RNA-seq data derived from ccRCC tumors in The Cancer Genome Atlas (TCGA were used to demonstrate differential expression of genes in primary tumor tissue from patients that had metastasis at baseline (n = 79 compared to those that did not develop metastasis for at least 2 years (n = 187. Functional analysis was conducted to identify key signaling pathways by using Ingenuity Pathway Analysis. Of 10 kinase genes overexpressed in metastases compared to primary tumor in the discovery cohort, 9 genes were also differentially expressed in TCGA primary tumors with metastasis at baseline compared to primary tumors without metastasis for at least 2 years: EPHB2, AURKA, GSG2, IKBKE, MELK, CSK, CHEK2, CDC7 and MAP3K8; p<0.001. The top pathways overexpressed in M tissue were pyridoxal 5'-phosphate salvage, salvage pathways of pyrimidine ribonucleotides, NF-kB signaling, NGF signaling and cell cycle control of chromosomal replication. The 9 kinase genes validated to be over-expressed in metastatic ccRCC may represent currently unrecognized but potentially actionable therapeutic targets that warrant functional validation.

  7. LTB4 stimulates growth of human pancreatic cancer cells via MAPK and PI-3 kinase pathways

    International Nuclear Information System (INIS)

    Tong, W.-G.; Ding, X.-Z.; Talamonti, Mark S.; Bell, Richard H.; Adrian, Thomas E.

    2005-01-01

    We have previously shown the importance of LTB4 in human pancreatic cancer. LTB4 receptor antagonists block growth and induce apoptosis in pancreatic cancer cells both in vitro and in vivo. Therefore, we investigated the effect of LTB4 on proliferation of human pancreatic cancer cells and the mechanisms involved. LTB4 stimulated DNA synthesis and proliferation of both PANC-1 and AsPC-1 human pancreatic cancer cells, as measured by thymidine incorporation and cell number. LTB4 stimulated rapid and transient activation of MEK and ERK1/2 kinases. The MEK inhibitors, PD98059 and U0126, blocked LTB4-stimulated ERK1/2 activation and cell proliferation. LTB4 also stimulated phosphorylation of p38 MAPK; however, the p38 MAPK inhibitor, SB203580, failed to block LTB4-stimulated growth. The activity of JNK/SAPK was not affected by LTB4 treatment. Phosphorylation of Akt was also induced by LTB4 and this effect was blocked by the PI-3 kinase inhibitor wortmannin, which also partially blocked LTB4-stimulated cell proliferation. In conclusion, LTB4 stimulates proliferation of human pancreatic cancer cells through MEK/ERK and PI-3 kinase/Akt pathways, while p38 MPAK and JNK/SAPK are not involved

  8. Evaluation of preparation methods for MS-based analysis of intestinal epithelial cell proteomes

    DEFF Research Database (Denmark)

    Hesselager, Marianne Overgaard; Codrea, Marius Cosmin; Bendixen, Emøke

    2015-01-01

    analyzed by LC and electrospray QTOF-MS. The methods were evaluated according to efficiency, purity, transmembrane protein recovery, as well as for suitability to large-scale preparations. Our data clearly demonstrate that mucosal shaving is by far the best-suited method for in-depth MS analysis in terms...... are low in abundance, and large amounts of sample is needed for their preparation and for undertaking MS-based analysis. The aim of this study was to evaluate three different methods for isolation and preparation of pig intestinal epithelial cells for MS-based analysis of the proteome. Samples were...... of ease and speed of sample preparation, as well as protein recovery. In comparison, more gentle methods where intestinal epithelial cells are harvested by shaking are more time consuming, result in lower protein yield, and are prone to increased technical variation due to multiple steps involved....

  9. Intestinal Immunomodulatory Cells (T Lymphocytes: A Bridge between Gut Microbiota and Diabetes

    Directory of Open Access Journals (Sweden)

    Qingwei Li

    2018-01-01

    Full Text Available Diabetes mellitus (DM is one of the most familiar chronic diseases threatening human health. Recent studies have shown that the development of diabetes is closely related to an imbalance of the gut microbiota. Accordingly, there is increasing interest in how changes in the gut microbiota affect diabetes and its underlying mechanisms. Immunomodulatory cells play important roles in maintaining the normal functioning of the human immune system and in maintaining homeostasis. Intestinal immunomodulatory cells (IICs are located in the intestinal mucosa and are regarded as an intermediary by which the gut microbiota affects physiological and pathological properties. Diabetes can be regulated by IICs, which act as a bridge linking the gut microbiota and DM. Understanding this bridge role of IICs may clarify the mechanisms by which the gut microbiota contributes to DM. Based on recent research, we summarize this process, thereby providing a basis for further studies of diabetes and other similar immune-related diseases.

  10. Protein Kinase D Enzymes as Regulators of EMT and Cancer Cell Invasion

    Directory of Open Access Journals (Sweden)

    Nisha Durand

    2016-02-01

    Full Text Available The Protein Kinase D (PKD isoforms PKD1, PKD2, and PKD3 are effectors of the novel Protein Kinase Cs (nPKCs and diacylglycerol (DAG. PKDs impact diverse biological processes like protein transport, cell migration, proliferation, epithelial to mesenchymal transition (EMT and apoptosis. PKDs however, have distinct effects on these functions. While PKD1 blocks EMT and cell migration, PKD2 and PKD3 tend to drive both processes. Given the importance of EMT and cell migration to the initiation and progression of various malignancies, abnormal expression of PKDs has been reported in multiple types of cancers, including breast, pancreatic and prostate cancer. In this review, we discuss how EMT and cell migration are regulated by PKD isoforms and the significance of this regulation in the context of cancer development.

  11. W/kit gene required for interstitial cells of Cajal and for intestinal pacemaker activity

    DEFF Research Database (Denmark)

    Huizinga, J D; Thuneberg, L; Klüppel, M

    1995-01-01

    The pacemaker activity in the mammalian gut is responsible for generating anally propagating phasic contractions. The cellular basis for this intrinsic activity is unknown. The smooth muscle cells of the external muscle layers and the innervated cellular network of interstitial cells of Cajal......, which is closely associated with the external muscle layers of the mammalian gut, have both been proposed to stimulate pacemaker activity. The interstitial cells of Cajal were identified in the last century but their developmental origin and function have remained unclear. Here we show...... of Cajal associated with Auerbach's nerve plexus and intestinal pacemaker activity....

  12. HNF1 alpha activates the aminopeptidase N promoter in intestinal (Caco-2) cells

    DEFF Research Database (Denmark)

    Olsen, Jørgen; Laustsen, Lotte; Troelsen, J

    1994-01-01

    The importance of HNF1 binding proteins for intestinal aminopeptidase N expression was investigated using the Caco-2 cell-line. Aminopeptidase N promoter activity in Caco-2 cells depends on the HNF1 element (positions -85 to -58) and co-transfection with an HNF1 alpha expression vector demonstrates...... a direct activation of the promoter by HNF1 alpha through this element. Electrophoretic mobility shift assays using nuclear extracts from Caco-2 cells show the presence of high amounts of HNF1 binding proteins irrespective of their state of differentiation....

  13. A multi-chamber microfluidic intestinal barrier model using Caco-2 cells for drug transport studies

    DEFF Research Database (Denmark)

    Tan, Hsih-Yin; Trier, Sofie; Rahbek, Ulrik L

    2018-01-01

    with platinum wires, enabling parallel real-time monitoring of barrier integrity for the eight chambers. Additionally, the translucent porous Teflon membrane enabled optical monitoring of cell monolayers. The device was developed and tested with the Caco-2 intestinal model, and compared to the conventional...... through permeability studies of mannitol, dextran and insulin, alone or in combination with the absorption enhancer tetradecylmaltoside (TDM). The thiol-ene-based microchip material and electrodes were highly compatible with cell growth. In fact, Caco-2 cells cultured in the device displayed...

  14. IL-2 receptor γ-chain molecule is critical for intestinal T-cell reconstitution in humanized mice.

    Science.gov (United States)

    Denton, P W; Nochi, T; Lim, A; Krisko, J F; Martinez-Torres, F; Choudhary, S K; Wahl, A; Olesen, R; Zou, W; Di Santo, J P; Margolis, D M; Garcia, J V

    2012-09-01

    Intestinal immune cells are important in host defense, yet the determinants for human lymphoid homeostasis in the intestines are poorly understood. In contrast, lymphoid homeostasis has been studied extensively in mice, where the requirement for a functional common γ-chain molecule has been established. We hypothesized that humanized mice could offer insights into human intestinal lymphoid homeostasis if generated in a strain with an intact mouse common γ-chain molecule. To address this hypothesis, we used three mouse strains (non-obese diabetic (NOD)/severe-combined immunodeficient (SCID) (N/S); NOD/SCID γ-chain(-/-) (NSG); and Rag2(-/-) γ-chain(-/-) (DKO)) and two humanization techniques (bone marrow liver thymus (BLT) and human CD34(+) cell bone marrow transplant of newborn mice (hu)) to generate four common types of humanized mice: N/S-BLT, NSG-BLT, NSG-hu, and DKO-hu mice. The highest levels of intestinal human T cells throughout the small and large intestines were observed in N/S-BLT mice, which have an intact common γ-chain molecule. Furthermore, the small intestine lamina propria T-cell populations of N/S-BLT mice exhibit a human intestine-specific surface phenotype. Thus, the extensive intestinal immune reconstitution of N/S-BLT mice was both quantitatively and qualitatively better when compared with the other models tested such that N/S-BLT mice are well suited for the analysis of human intestinal lymphocyte trafficking and human-specific diseases affecting the intestines.

  15. Intestinal diffuse large B-cell lymphoma: an evaluation of different staging systems.

    Science.gov (United States)

    Hwang, Hee Sang; Yoon, Dok Hyun; Suh, Cheolwon; Park, Chan-Sik; Huh, Jooryung

    2014-01-01

    The gastrointestinal tract is the most common primary extranodal site for diffuse large B-cell lymphoma (DLBCL). However, there is no consensus on the most appropriate staging system for intestinal DLBCL. We evaluated the utility of the modified Ann Arbor system, the Lugano system, and the Paris staging system (a modification of the Tumor, Node, Metastases [TNM] staging for epithelial tumors) in 66 cases of resected intestinal DLBCL. The cases were treated with surgery, plus either cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) chemotherapy alone (n=26) or with the addition of rituximab immunotherapy (n=40). Median follow-up time was 40.4 months (range, 2.1-171.6 months). Fifty-six patients (84.8%) achieved complete remission. The overall 5-yr survival rate was 86.4% (57/66). Of the stage categories defined for each staging system, only the T stage of the Paris classification showed prognostic significance for overall survival by univariate analysis. However, none of the stage parameters was significantly correlated with patient survival on multivariate analysis. In conclusion, the results suggest that the T stage of the Paris classification system may be a prognostic indicator in intestinal DLBCL. The results also imply that in surgically resected intestinal DLBCL, the addition of rituximab to the CHOP regimen does not confer significant survival advantage.

  16. Sedentary lifestyle related exosomal release of Hotair from gluteal-femoral fat promotes intestinal cell proliferation.

    Science.gov (United States)

    Lu, Xiaozhao; Bai, Danna; Liu, Xiangwei; Zhou, Chen; Yang, Guodong

    2017-03-31

    Pioneering epidemiological work has established strong association of sedentary lifestyle and obesity with the risk of colorectal cancer, while the detailed underlying mechanism remains unknown. Here we show that Hotair (HOX transcript antisense RNA) is a pro-adipogenic long non-coding RNA highly expressed in gluteal-femoral fat over other fat depots. Hotair knockout in adipose tissue results in gluteal-femoral fat defect. Squeeze of the gluteal-femoral fat induces intestinal proliferation in wildtype mice, while not in Hotair knockout mice. Mechanistically, squeeze of the gluteal-femoral fat induces exosomal Hotair secretion mainly by transcriptional upregulation of Hotair via NFκB. And increased exosomal Hotair in turn circulates in the blood and is partially endocytosed by the intestine, finally promoting the stemness and proliferation of intestinal stem/progenitor cells via Wnt activation. Clinically, obese subjects with sedentary lifestyle have much higher exosomal HOTAIR expression in the serum. These findings establish that sedentary lifestyle promotes exosomal Hotair release from the gluteal-femoral fat, which in turn facilitates intestinal stem and/or progenitor proliferation, raising a possible link between sedentary lifestyle with colorectal tumorigenesis.

  17. Eosinophils may play regionally disparate roles in influencing IgA(+) plasma cell numbers during large and small intestinal inflammation.

    Science.gov (United States)

    Forman, Ruth; Bramhall, Michael; Logunova, Larisa; Svensson-Frej, Marcus; Cruickshank, Sheena M; Else, Kathryn J

    2016-05-31

    Eosinophils are innate immune cells present in the intestine during steady state conditions. An intestinal eosinophilia is a hallmark of many infections and an accumulation of eosinophils is also observed in the intestine during inflammatory disorders. Classically the function of eosinophils has been associated with tissue destruction, due to the release of cytotoxic granule contents. However, recent evidence has demonstrated that the eosinophil plays a more diverse role in the immune system than previously acknowledged, including shaping adaptive immune responses and providing plasma cell survival factors during the steady state. Importantly, it is known that there are regional differences in the underlying immunology of the small and large intestine, but whether there are differences in context of the intestinal eosinophil in the steady state or inflammation is not known. Our data demonstrates that there are fewer IgA(+) plasma cells in the small intestine of eosinophil-deficient ΔdblGATA-1 mice compared to eosinophil-sufficient wild-type mice, with the difference becoming significant post-infection with Toxoplasma gondii. Remarkably, and in complete contrast, the absence of eosinophils in the inflamed large intestine does not impact on IgA(+) cell numbers during steady state, and is associated with a significant increase in IgA(+) cells post-infection with Trichuris muris compared to wild-type mice. Thus, the intestinal eosinophil appears to be less important in sustaining the IgA(+) cell pool in the large intestine compared to the small intestine, and in fact, our data suggests eosinophils play an inhibitory role. The dichotomy in the influence of the eosinophil over small and large intestinal IgA(+) cells did not depend on differences in plasma cell growth factors, recruitment potential or proliferation within the different regions of the gastrointestinal tract (GIT). We demonstrate for the first time that there are regional differences in the requirement of

  18. Enhancing Oral Vaccine Potency by Targeting Intestinal M Cells

    Czech Academy of Sciences Publication Activity Database

    Azizi, A.; Kumar, A.; Diaz-Mitoma, F.; Městecký, Jiří

    2010-01-01

    Roč. 6, č. 11 (2010) ISSN 1553-7366 Institutional research plan: CEZ:AV0Z50200510 Keywords : PATCH M-CELLS * UROPATHOGENIC ESCHERICHIA-COLI * MUCOSAL IMMUNE-SYSTEM Subject RIV: EE - Microbiology, Virology Impact factor: 9.079, year: 2010

  19. Fusion between Intestinal epithelial cells and macrophages in a cancer context results in nuclear reprogramming.

    Science.gov (United States)

    Powell, Anne E; Anderson, Eric C; Davies, Paige S; Silk, Alain D; Pelz, Carl; Impey, Soren; Wong, Melissa H

    2011-02-15

    The most deadly phase in cancer progression is attributed to the inappropriate acquisition of molecular machinery leading to metastatic transformation and spread of disease to distant organs. Although it is appreciated that metastasis involves epithelial-mesenchymal interplay, the underlying mechanism defining this process is poorly understood. Specifically, how cancer cells evade immune surveillance and gain the ability to navigate the circulatory system remains a focus. One possible mechanism underlying metastatic conversion is fusion between blood-derived immune cells and cancer cells. While this notion is a century old, in vivo evidence that cell fusion occurs within tumors and imparts genetic or physiologic changes remains controversial. We have previously demonstrated in vivo cell fusion between blood cells and intestinal epithelial cells in an injury setting. Here, we hypothesize that immune cells, such as macrophages, fuse with tumor cells imparting metastatic capabilities by transferring their cellular identity. We used parabiosis to introduce fluorescent-labeled bone marrow-derived cells to mice with intestinal tumors, finding that fusion between circulating blood-derived cells and tumor epithelium occurs during the natural course of tumorigenesis. Moreover, we identify the macrophage as a key cellular partner for this process. Interestingly, cell fusion hybrids retain a transcriptome identity characteristic of both parental derivatives, while also expressing a unique subset of transcripts. Our data supports the novel possibility that tumorigenic cell fusion may impart physical behavior attributed to migratory macrophages, including navigation of circulation and immune evasion. As such, cell fusion may represent a promising novel mechanism underlying the metastatic conversion of cancer cells. ©2011 AACR.

  20. The MAP kinase-activated protein kinase Rck2p regulates cellular responses to cell wall stresses, filamentation and virulence in the human fungal pathogen Candida albicans.

    Science.gov (United States)

    Li, Xichuan; Du, Wei; Zhao, Jingwen; Zhang, Lilin; Zhu, Zhiyan; Jiang, Linghuo

    2010-06-01

    Rck2p is the Hog1p-MAP kinase-activated protein kinase required for the attenuation of protein synthesis in response to an osmotic challenge in Saccharomyces cerevisiae. Rck2p also regulates rapamycin sensitivity in both S. cerevisiae and Candida albicans. In this study, we demonstrate that the deletion of CaRCK2 renders C. albicans cells sensitive to, and CaRck2p translocates from the cytosol to the nucleus in response to, cell wall stresses caused by Congo red, Calcoflor White, elevated heat and zymolyase. However, the kinase activity of CaRck2p is not required for the cellular response to these cell wall stresses. Furthermore, transcripts of cell wall protein-encoding genes CaBGL2, CaHWP1 and CaXOG1 are reduced in C. albicans cells lacking CaRCK2. The deletion of CaRCK2 also reduces the in vitro filamentation of C. albicans and its virulence in a mouse model of systemic candidasis. The kinase activity of CaRck2p is required for the virulence, but not for the in vitro filamentation, in C. albicans. Therefore, Rck2p regulates cellular responses to cell wall stresses, filamentation and virulence in the human fungal pathogen C. albicans.

  1. GLP-1 and GIP are colocalized in a subset of endocrine cells in the small intestine

    DEFF Research Database (Denmark)

    Mortensen, Kristine; Christensen, Louise Lundby; Holst, Jens Juul

    2003-01-01

    BACKGROUND: The incretin hormones GIP and GLP-1 are thought to be produced in separate endocrine cells located in the proximal and distal ends of the mammalian small intestine, respectively. METHODS AND RESULTS: Using double immunohistochemistry and in situ hybridization, we found that GLP-1 was ....... CONCLUSIONS: Our results provide a morphological basis to suggest simultaneous, rather than sequential, secretion of these hormones by postprandial luminal stimulation....

  2. Role of BK channels in the apoptotic volume decrease in native eel intestinal cells

    DEFF Research Database (Denmark)

    Lionetto, Maria Giulia; Giordano, Maria Elena; Calisi, Antonio

    2010-01-01

    High conductance Ca(+)-activated K(+) channels (BK channels) have previously been demonstrated in the eel intestine. They are specifically activated following a hypotonic stress and sustain Regulatory Volume Decrease (RVD). The aim of the present work was to address the possible role...... enterocytes that BK channels, which are involved in RVD in these cells, plays also a crucial role in the AVD process and in the progression of apoptosis....

  3. Autoradiographic quantification of vasoactive intestinal peptide binding sites in sections from human blood mononuclear cell pellets

    Energy Technology Data Exchange (ETDEWEB)

    Gutkind, J.S.; Kurihara, M.; Castren, E.; Saavedra, J.M.

    1988-09-01

    Quantitative autoradiographic methods were utilized to characterize specific, high-affinity vasoactive intestinal peptide binding sites (Kd = 310 +/- 60 pmol/L; Bmax = 93 +/- 11 fmol/mg protein) in frozen sections obtained from a mononuclear cell pellet derived from 20 ml of human blood. The method is at least one order of magnitude more sensitive than conventional membrane binding techniques, and it has the potential for wide applications in studies of neuropeptide, biogenic amine, and drug binding in clinical samples.

  4. Autoradiographic quantification of vasoactive intestinal peptide binding sites in sections from human blood mononuclear cell pellets

    International Nuclear Information System (INIS)

    Gutkind, J.S.; Kurihara, M.; Castren, E.; Saavedra, J.M.

    1988-01-01

    Quantitative autoradiographic methods were utilized to characterize specific, high-affinity vasoactive intestinal peptide binding sites (Kd = 310 +/- 60 pmol/L; Bmax = 93 +/- 11 fmol/mg protein) in frozen sections obtained from a mononuclear cell pellet derived from 20 ml of human blood. The method is at least one order of magnitude more sensitive than conventional membrane binding techniques, and it has the potential for wide applications in studies of neuropeptide, biogenic amine, and drug binding in clinical samples

  5. Commensal Streptococcus salivarius Modulates PPARγ Transcriptional Activity in Human Intestinal Epithelial Cells.

    Directory of Open Access Journals (Sweden)

    Benoît Couvigny

    Full Text Available The impact of commensal bacteria in eukaryotic transcriptional regulation has increasingly been demonstrated over the last decades. A multitude of studies have shown direct effects of commensal bacteria from local transcriptional activity to systemic impact. The commensal bacterium Streptococcus salivarius is one of the early bacteria colonizing the oral and gut mucosal surfaces. It has been shown to down-regulate nuclear transcription factor (NF-кB in human intestinal cells, a central regulator of the host mucosal immune system response to the microbiota. In order to evaluate its impact on a further important transcription factor shown to link metabolism and inflammation in the intestine, namely PPARγ (peroxisome proliferator-activated receptor, we used human intestinal epithelial cell-lines engineered to monitor PPARγ transcriptional activity in response to a wide range of S. salivarius strains. We demonstrated that different strains from this bacterial group share the property to inhibit PPARγ activation independently of the ligand used. First attempts to identify the nature of the active compounds showed that it is a low-molecular-weight, DNase-, proteases- and heat-resistant metabolite secreted by S. salivarius strains. Among PPARγ-targeted metabolic genes, I-FABP and Angptl4 expression levels were dramatically reduced in intestinal epithelial cells exposed to S. salivarius supernatant. Both gene products modulate lipid accumulation in cells and down-regulating their expression might consequently affect host health. Our study shows that species belonging to the salivarius group of streptococci impact both host inflammatory and metabolic regulation suggesting a possible role in the host homeostasis and health.

  6. Fluorescent peptide biosensor for probing the relative abundance of cyclin-dependent kinases in living cells.

    Directory of Open Access Journals (Sweden)

    Laetitia Kurzawa

    Full Text Available Cyclin-dependant kinases play a central role in coordinating cell growth and division, and in sustaining proliferation of cancer cells, thereby constituting attractive pharmacological targets. However, there are no direct means of assessing their relative abundance in living cells, current approaches being limited to antigenic and proteomic analysis of fixed cells. In order to probe the relative abundance of these kinases directly in living cells, we have developed a fluorescent peptide biosensor with biligand affinity for CDKs and cyclins in vitro, that retains endogenous CDK/cyclin complexes from cell extracts, and that bears an environmentally-sensitive probe, whose fluorescence increases in a sensitive fashion upon recognition of its targets. CDKSENS was introduced into living cells, through complexation with the cell-penetrating carrier CADY2 and applied to assess the relative abundance of CDK/Cyclins through fluorescence imaging and ratiometric quantification. This peptide biosensor technology affords direct and sensitive readout of CDK/cyclin complex levels, and reports on differences in complex formation when tampering with a single CDK or cyclin. CDKSENS further allows for detection of differences between different healthy and cancer cell lines, thereby enabling to distinguish cells that express high levels of these heterodimeric kinases, from cells that present decreased or defective assemblies. This fluorescent biosensor technology provides information on the overall status of CDK/Cyclin complexes which cannot be obtained through antigenic detection of individual subunits, in a non-invasive fashion which does not require cell fixation or extraction procedures. As such it provides promising perspectives for monitoring the response to therapeutics that affect CDK/Cyclin abundance, for cell-based drug discovery strategies and fluorescence-based cancer diagnostics.

  7. A unique cause of intestinal and splenic infarction in a sickle cell trait patient.

    Science.gov (United States)

    Asfaw, Sofya H; Falk, Gavin A; Morris-Stiff, Gareth; Tuthill, Ralph J; Moorman, Matthew L; Samotowka, Michael A

    2013-01-01

    Sickle-cell trait is a common genetic abnormality in the African American population. A sickle-cell crisis in a patient with sickle-cell trait is uncommon at best. Abdominal painful crises are typical of patients with sickle cell anemia. The treatment for an abdominal painful crisis is usually medical and rarely surgical. We present the case of a cocaine-induced sickle-cell crisis in a sickle-cell trait patient that resulted in splenic, intestinal, and cerebral infarctions and multisystem organ failure necessitating a splenectomy, subtotal colectomy, and small bowel resection. This case highlights the diagnostic dilemma that abdominal pain can present in the sickle-cell population and illustrates the importance of recognizing the potential for traditionally medically managed illnesses to become surgical emergencies.

  8. A Unique Cause of Intestinal and Splenic Infarction in a Sickle Cell Trait Patient

    Directory of Open Access Journals (Sweden)

    Sofya H. Asfaw

    2013-01-01

    Full Text Available Sickle-cell trait is a common genetic abnormality in the African American population. A sickle-cell crisis in a patient with sickle-cell trait is uncommon at best. Abdominal painful crises are typical of patients with sickle cell anemia. The treatment for an abdominal painful crisis is usually medical and rarely surgical. We present the case of a cocaine-induced sickle-cell crisis in a sickle-cell trait patient that resulted in splenic, intestinal, and cerebral infarctions and multisystem organ failure necessitating a splenectomy, subtotal colectomy, and small bowel resection. This case highlights the diagnostic dilemma that abdominal pain can present in the sickle-cell population and illustrates the importance of recognizing the potential for traditionally medically managed illnesses to become surgical emergencies.

  9. Human cytosolic thymidine kinase: purification and physical characterization of the enzyme from HeLa cells

    International Nuclear Information System (INIS)

    Sherley, J.L.; Kelly, T.J.

    1988-01-01

    The mammalian cytosolic thymidine kinase is one of a number of enzymes involved in DNA replication whose activities increase dramatically during S phase of the cell cycle. As a first step in defining the mechanisms that control the S phase induction of thymidine kinase activity, the authors have purified the human enzyme from HeLa cells and raised a specific immune serum against the purified protein. The enzyme was isolated from cells arrested in S phase by treatment with methotrexate and purified to near homogeneity by ion-exchange and affinity chromatography. Stabilization of the purified enzyme was achieved by the addition of digitonin. An electrophoretic R/sub m/ of 0.2 in nondenaturing gels characterizes the purified enzyme activity as cytosolic thymidine kinase. The enzyme has a Stoke's radius of 40 A determined by gel filtration and a sedimentation coefficient of 5.5 S determined by glycerol gradient sedimentation. Based on these hydrodynamic values, a native molecular weight of 96,000 was calculated for the purified enzyme. When electrophoresed in denaturing sodium dodecyl sulfate-polyacrylamide gels under reducing conditions, the most purified enzyme fraction was found to contain one predominant polypeptide of M/sub r/ = 24,000. Several lines of evidence indicate that this polypeptide is responsible for thymidine kinase enzymatic activity

  10. The effect of storage time of human red cells on intestinal microcirculatory oxygenation in a rat isovolemic exchange model

    NARCIS (Netherlands)

    Raat, N. J.; Verhoeven, A. J.; Mik, E. G.; Gouwerok, C. W.; Verhaar, R.; Goedhart, P. T.; de Korte, D.; Ince, C.

    2005-01-01

    Objective: To determine whether the storage time of human leukodepleted red blood cell concentrates compromises intestinal microvascular oxygen concentration oxygen (muPo(2)) during isovolemic exchange transfusion at low hematocrit. Design: Prospective, randomized, controlled study. Setting:

  11. Xenobiotic effects on intestinal stem cell proliferation in adult honey bee (Apis mellifera L) workers.

    Science.gov (United States)

    Forkpah, Cordelia; Dixon, Luke R; Fahrbach, Susan E; Rueppell, Olav

    2014-01-01

    The causes of the current global decline in honey bee health are unknown. One major group of hypotheses invokes the pesticides and other xenobiotics to which this important pollinator species is often exposed. Most studies have focused on mortality or behavioral deficiencies in exposed honey bees while neglecting other biological functions and target organs. The midgut epithelium of honey bees presents an important interface between the insect and its environment. It is maintained by proliferation of intestinal stem cells throughout the adult life of honey bees. We used caged honey bees to test multiple xenobiotics for effects on the replicative activity of the intestinal stem cells under laboratory conditions. Most of the tested compounds did not alter the replicative activity of intestinal stem cells. However, colchicine, methoxyfenozide, tetracycline, and a combination of coumaphos and tau-fluvalinate significantly affected proliferation rate. All substances except methoxyfenozide decreased proliferation rate. Thus, the results indicate that some xenobiotics frequently used in apiculture and known to accumulate in honey bee hives may have hitherto unknown physiological effects. The nutritional status and the susceptibility to pathogens of honey bees could be compromised by the impacts of xenobiotics on the maintenance of the midgut epithelium. This study contributes to a growing body of evidence that more comprehensive testing of xenobiotics may be required before novel or existing compounds can be considered safe for honey bees and other non-target species.

  12. Effects of protein kinase C activators on phorbol ester-sensitive and -resistant EL4 thymoma cells.

    Science.gov (United States)

    Sansbury, H M; Wisehart-Johnson, A E; Qi, C; Fulwood, S; Meier, K E

    1997-09-01

    Phorbol ester-sensitive EL4 murine thymoma cells respond to phorbol 12-myristate 13-acetate with activation of ERK mitogen-activated protein kinases, synthesis of interleukin-2, and death, whereas phorbol ester-resistant variants of this cell line do not exhibit these responses. Additional aspects of the resistant phenotype were examined, using a newly-established resistant cell line. Phorbol ester induced morphological changes, ERK activation, calcium-dependent activation of the c-Jun N-terminal kinase (JNK), interleukin-2 synthesis, and growth inhibition in sensitive but not resistant cells. A series of protein kinase C activators caused membrane translocation of protein kinase C's (PKCs) alpha, eta, and theta in both cell lines. While PKC eta was expressed at higher levels in sensitive than in resistant cells, overexpression of PKC eta did not restore phorbol ester-induced ERK activation to resistant cells. In sensitive cells, PKC activators had similar effects on cell viability and ERK activation, but differed in their abilities to induce JNK activation and interleukin-2 synthesis. PD 098059, an inhibitor of the mitogen activated protein (MAP)/ERK kinase kinase MEK, partially inhibited ERK activation and completely blocked phorbol ester-induced cell death in sensitive cells. Thus MEK and/or ERK activation, but not JNK activation or interleukin-2 synthesis, appears to be required for phorbol ester-induced toxicity. Alterations in phorbol ester response pathways, rather than altered expression of PKC isoforms, appear to confer phorbol ester resistance to EL4 cells.

  13. A comprehensive target selectivity survey of the BCR-ABL kinase inhibitor INNO-406 by kinase profiling and chemical proteomics in chronic myeloid leukemia cells.

    Science.gov (United States)

    Rix, U; Remsing Rix, L L; Terker, A S; Fernbach, N V; Hantschel, O; Planyavsky, M; Breitwieser, F P; Herrmann, H; Colinge, J; Bennett, K L; Augustin, M; Till, J H; Heinrich, M C; Valent, P; Superti-Furga, G

    2010-01-01

    Resistance to the BCR-ABL tyrosine kinase inhibitor imatinib poses a pressing challenge in treating chronic myeloid leukemia (CML). This resistance is often caused by point mutations in the ABL kinase domain or by overexpression of LYN. The second-generation BCR-ABL inhibitor INNO-406 is known to inhibit most BCR-ABL mutants and LYN efficiently. Knowledge of its full target spectrum would provide the molecular basis for potential side effects or suggest novel therapeutic applications and possible combination therapies. We have performed an unbiased chemical proteomics native target profile of INNO-406 in CML cells combined with functional assays using 272 recombinant kinases thereby identifying several new INNO-406 targets. These include the kinases ZAK, DDR1/2 and various ephrin receptors. The oxidoreductase NQO2, inhibited by both imatinib and nilotinib, is not a relevant target of INNO-406. Overall, INNO-406 has an improved activity over imatinib but a slightly broader target profile than both imatinib and nilotinib. In contrast to dasatinib and bosutinib, INNO-406 does not inhibit all SRC kinases and most TEC family kinases and is therefore expected to elicit fewer side effects. Altogether, these properties may make INNO-406 a valuable component in the drug arsenal against CML.

  14. Tyrosine kinase inhibitors and mesenchymal stromal cells: effects on self-renewal, commitment and functions

    Science.gov (United States)

    Borriello, Adriana; Caldarelli, Ilaria; Bencivenga, Debora; Stampone, Emanuela; Perrotta, Silverio; Oliva, Adriana; Ragione, Fulvio Della

    2017-01-01

    The hope of selectively targeting cancer cells by therapy and eradicating definitively malignancies is based on the identification of pathways or metabolisms that clearly distinguish “normal” from “transformed” phenotypes. Some tyrosine kinase activities, specifically unregulated and potently activated in malignant cells, might represent important targets of therapy. Consequently, tyrosine kinase inhibitors (TKIs) might be thought as the “vanguard” of molecularly targeted therapy for human neoplasias. Imatinib and the successive generations of inhibitors of Bcr-Abl1 kinase, represent the major successful examples of TKI use in cancer treatment. Other tyrosine kinases have been selected as targets of therapy, but the efficacy of their inhibition, although evident, is less definite. Two major negative effects exist in this therapeutic strategy and are linked to the specificity of the drugs and to the role of the targeted kinase in non-malignant cells. In this review, we will discuss the data available on the TKIs effects on the metabolism and functions of mesenchymal stromal cells (MSCs). MSCs are widely distributed in human tissues and play key physiological roles; nevertheless, they might be responsible for important pathologies. At present, bone marrow (BM) MSCs have been studied in greater detail, for both embryological origins and functions. The available data are evocative of an unexpected degree of complexity and heterogeneity of BM-MSCs. It is conceivable that this grade of intricacy occurs also in MSCs of other organs. Therefore, in perspective, the negative effects of TKIs on MSCs might represent a critical problem in long-term cancer therapies based on such inhibitors. PMID:27750212

  15. Activation of Cyclin-Dependent Kinase 5 Is a Consequence of Cell Death

    Directory of Open Access Journals (Sweden)

    Yixia Ye

    2009-01-01

    Full Text Available Cyclin-dependent kinase 5 (Cdk5 is similar to other Cdks but is activated during cell differentiation and cell death rather than cell division. Since activation of Cdk5 has been reported in many situations leading to cell death, we attempted to determine if it was required for any form of cell death. We found that Cdk5 is activated during apoptotic deaths and that the activation can be detected even when the cells continue to secondary necrosis. This activation can occur in the absence of Bim, calpain, or neutral cathepsins. The kinase is typically activated by p25, derived from p35 by calpain-mediated cleavage, but inhibition of calpain does not affect cell death or the activation of Cdk5. Likewise, RNAi-forced suppression of the synthesis of Cdk5 does not affect the incidence or kinetics of cell death. We conclude that Cdk5 is activated as a consequence of metabolic changes that are common to many forms of cell death. Thus its activation suggests processes during cell death that will be interesting or important to understand, but activation of Cdk5 is not necessary for cells to die.

  16. Indomethacin promotes apoptosis in gastric cancer cells through concomitant degradation of Survivin and Aurora B kinase proteins.

    Science.gov (United States)

    Chiou, Shiun-Kwei; Hoa, Neil; Hodges, Amy; Ge, Lishen; Jadus, Martin R

    2014-09-01

    Regular usage of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with reduced incidence of a variety of cancers. The molecular mechanisms underlying these chemopreventive effects remain poorly understood. This current investigation showed that in gastric cancer cells: (1) Indomethacin treatment enhanced the degradation of chromosomal passenger proteins, Survivin and Aurora B kinase; (2) Indomethacin treatment down-regulated Aurora B kinase activity in a cell cycle-independent fashion; (3) siRNA knockdown of Survivin level promoted Aurora B kinase protein degradation, and vice versa; (4) ectopic overexpression of Survivin blocked reduction of Aurora B kinase level and activity by indomethacin treatment, and vice versa; (5) siRNA knockdown of Aurora B kinase level and AZD1152 inhibition of its activity induced apoptosis, and overexpression of Aurora B kinase inhibited indomethacin-induced apoptosis; (6) indomethacin treatment reduced Aurora B kinase level, coinciding with reduction of Survivin level and induction of apoptosis, in KATO III and HT-29 cells, and in mouse gastric mucosa. A role for Aurora B kinase function in NSAID-induced apoptosis was not previously explored. Thus this report provides better understanding of the molecular mechanisms underlying the anti-cancer effect of NSAIDs by elucidating a significant role for Aurora B kinase in indomethacin-induced apoptosis.

  17. Thyroid Hormone-Induced Activation of Notch Signaling is Required for Adult Intestinal Stem Cell Development During Xenopus Laevis Metamorphosis.

    Science.gov (United States)

    Hasebe, Takashi; Fujimoto, Kenta; Kajita, Mitsuko; Fu, Liezhen; Shi, Yun-Bo; Ishizuya-Oka, Atsuko

    2017-04-01

    In Xenopus laevis intestine during metamorphosis, the larval epithelial cells are removed by apoptosis, and the adult epithelial stem (AE) cells appear concomitantly. They proliferate and differentiate to form the adult epithelium (Ep). Thyroid hormone (TH) is well established to trigger this remodeling by regulating the expression of various genes including Notch receptor. To study the role of Notch signaling, we have analyzed the expression of its components, including the ligands (DLL and Jag), receptor (Notch), and targets (Hairy), in the metamorphosing intestine by real-time reverse transcription-polymerase chain reaction and in situ hybridization or immunohistochemistry. We show that they are up-regulated during both natural and TH-induced metamorphosis in a tissue-specific manner. Particularly, Hairy1 is specifically expressed in the AE cells. Moreover, up-regulation of Hairy1 and Hairy2b by TH was prevented by treating tadpoles with a γ-secretase inhibitor (GSI), which inhibits Notch signaling. More importantly, TH-induced up-regulation of LGR5, an adult intestinal stem cell marker, was suppressed by GSI treatment. Our results suggest that Notch signaling plays a role in stem cell development by regulating the expression of Hairy genes during intestinal remodeling. Furthermore, we show with organ culture experiments that prolonged exposure of tadpole intestine to TH plus GSI leads to hyperplasia of secretory cells and reduction of absorptive cells. Our findings here thus provide evidence for evolutionarily conserved role of Notch signaling in intestinal cell fate determination but more importantly reveal, for the first time, an important role of Notch pathway in the formation of adult intestinal stem cells during vertebrate development. Stem Cells 2017;35:1028-1039. © 2016 The Authors STEM CELLS published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  18. Polarization of migrating monocytic cells is independent of PI 3-kinase activity.

    Directory of Open Access Journals (Sweden)

    Silvia Volpe

    Full Text Available BACKGROUND: Migration of mammalian cells is a complex cell type and environment specific process. Migrating hematopoietic cells assume a rapid amoeboid like movement when exposed to gradients of chemoattractants. The underlying signaling mechanisms remain controversial with respect to localization and distribution of chemotactic receptors within the plasma membrane and the role of PI 3-kinase activity in cell polarization. METHODOLOGY/PRINCIPAL FINDINGS: We present a novel model for the investigation of human leukocyte migration. Monocytic THP-1 cells transfected with the alpha(2A-adrenoceptor (alpha(2AAR display comparable signal transduction responses, such as calcium mobilization, MAP-kinase activation and chemotaxis, to the noradrenaline homologue UK 14'304 as when stimulated with CCL2, which binds to the endogenous chemokine receptor CCR2. Time-lapse video microscopy reveals that chemotactic receptors remain evenly distributed over the plasma membrane and that their internalization is not required for migration. Measurements of intramolecular fluorescence resonance energy transfer (FRET of alpha(2AAR-YFP/CFP suggest a uniform activation of the receptors over the entire plasma membrane. Nevertheless, PI 3-kinase activation is confined to the leading edge. When reverting the gradient of chemoattractant by moving the dispensing micropipette, polarized monocytes--in contrast to neutrophils--rapidly flip their polarization axis by developing a new leading edge at the previous posterior side. Flipping of the polarization axis is accompanied by re-localization of PI-3-kinase activity to the new leading edge. However, reversal of the polarization axis occurs in the absence of PI 3-kinase activation. CONCLUSIONS/SIGNIFICANCE: Accumulation and internalization of chemotactic receptors at the leading edge is dispensable for cell migration. Furthermore, uniformly distributed receptors allow the cells to rapidly reorient and adapt to changes in the

  19. Fasting protects mice from lethal DNA damage by promoting small intestinal epithelial stem cell survival.

    Science.gov (United States)

    Tinkum, Kelsey L; Stemler, Kristina M; White, Lynn S; Loza, Andrew J; Jeter-Jones, Sabrina; Michalski, Basia M; Kuzmicki, Catherine; Pless, Robert; Stappenbeck, Thaddeus S; Piwnica-Worms, David; Piwnica-Worms, Helen

    2015-12-22

    Short-term fasting protects mice from lethal doses of chemotherapy through undetermined mechanisms. Herein, we demonstrate that fasting preserves small intestinal (SI) architecture by maintaining SI stem cell viability and SI barrier function following exposure to high-dose etoposide. Nearly all SI stem cells were lost in fed mice, whereas fasting promoted sufficient SI stem cell survival to preserve SI integrity after etoposide treatment. Lineage tracing demonstrated that multiple SI stem cell populations, marked by Lgr5, Bmi1, or HopX expression, contributed to fasting-induced survival. DNA repair and DNA damage response genes were elevated in SI stem/progenitor cells of fasted etoposide-treated mice, which importantly correlated with faster resolution of DNA double-strand breaks and less apoptosis. Thus, fasting preserved SI stem cell viability as well as SI architecture and barrier function suggesting that fasting may reduce host toxicity in patients undergoing dose intensive chemotherapy.

  20. Physiology and pathophysiology of apoptosis in epithelial cells of the liver, pancreas, and intestine.

    Science.gov (United States)

    Jones, B A; Gores, G J

    1997-12-01

    Cell death of gastrointestinal epithelial cells occurs by a process referred to as apoptosis. In this review, we succinctly define apoptosis and summarize the role of apoptosis in the physiology and pathophysiology of epithelial cells in the liver, pancreas, and small and large intestine. The physiological mediators regulating apoptosis in gastrointestinal epithelial cells, when known, are discussed. Selected pathophysiological consequences of excessive apoptosis and inhibition of apoptosis are used to illustrate the significance of apoptosis in disease processes. These examples demonstrate that excessive apoptosis may result in epithelial cell atrophy, injury, and dysfunction, whereas inhibition of apoptosis results in hyperplasia and promotes malignant transformation. The specific cellular mechanisms responsible for dysregulation of epithelial cell apoptosis during pathophysiological disturbances are emphasized. Potential future areas of physiological research regarding apoptosis in gastrointestinal epithelia are highlighted when appropriate.

  1. Interstitial cells of Cajal in human small intestine. Ultrastructural identification and organization between the main smooth muscle layers

    DEFF Research Database (Denmark)

    Rumessen, J J; Thuneberg, L

    1991-01-01

    with elastin fibers. The organization shown in this study strongly supports the concept of interstitial cells of Cajal as important regulatory cells also in the human small intestine. The characteristic cytology and organization of interstitial cells of Cajal may provide a basis for future morphological......Previous morphological and electrophysiological studies have supported the hypothesis that interstitial cells of Cajal have important regulatory (pacemaker) functions in the gut. In the current study, interstitial cells of Cajal associated with Auerbach's plexus in human small intestine were...... studied. Freshly resected intestine was examined by light and electron microscopy. The interstitial cells of Cajal resembled modified smooth muscle cells. They had caveolae and dense bodies, an incomplete basal lamina, a very well-developed smooth endoplasmic reticulum, and abundant intermediate (10 nm...

  2. Src kinases in chondrosarcoma chemoresistance and migration: dasatinib sensitises to doxorubicin in TP53 mutant cells

    Science.gov (United States)

    van Oosterwijk, J G; van Ruler, M A J H; Briaire-de Bruijn, I H; Herpers, B; Gelderblom, H; van de Water, B; Bovée, J V M G

    2013-01-01

    Background: Chondrosarcomas are malignant cartilage-forming tumours of bone. Because of their resistance to conventional chemotherapy and radiotherapy, currently no treatment strategies exist for unresectable and metastatic chondrosarcoma. Previously, PI3K/AKT/GSK3β and Src kinase pathways were shown to be activated in chondrosarcoma cell lines. Our aim was to investigate the role of these kinases in chemoresistance and migration in chondrosarcoma in relation to TP53 mutation status. Methods: We used five conventional and three dedifferentiated chondrosarcoma cell lines and investigated the effect of PI3K/AKT/GSK3β pathway inhibition (enzastaurin) and Src pathway inhibition (dasatinib) in chemoresistance using WST assay and live cell imaging with AnnexinV staining. Immunohistochemistry on tissue microarrays (TMAs) containing 157 cartilaginous tumours was performed for Src family members. Migration assays were performed with the RTCA xCelligence System. Results: Src inhibition was found to overcome chemoresistance, to induce apoptosis and to inhibit migration. Cell lines with TP53 mutations responded better to combination therapy than wild-type cell lines (P=0.002). Tissue microarray immunohistochemistry confirmed active Src (pSrc) signalling, with Fyn being most abundantly expressed (76.1%). Conclusion: These results strongly indicate Src family kinases, in particular Fyn, as a potential target for the treatment of inoperable and metastatic chondrosarcomas, and to sensitise for doxorubicin especially in the presence of TP53 mutations. PMID:23922104

  3. STK33 kinase activity is nonessential in KRAS-dependent cancer cells.

    Science.gov (United States)

    Babij, Carol; Zhang, Yihong; Kurzeja, Robert J; Munzli, Anke; Shehabeldin, Amro; Fernando, Manory; Quon, Kim; Kassner, Paul D; Ruefli-Brasse, Astrid A; Watson, Vivienne J; Fajardo, Flordeliza; Jackson, Angela; Zondlo, James; Sun, Yu; Ellison, Aaron R; Plewa, Cherylene A; San, Miguel Tisha; Robinson, John; McCarter, John; Schwandner, Ralf; Judd, Ted; Carnahan, Josette; Dussault, Isabelle

    2011-09-01

    Despite the prevalence of KRAS mutations in human cancers, there remain no targeted therapies for treatment. The serine-threonine kinase STK33 has been proposed to be required for the survival of mutant KRAS-dependent cell lines, suggesting that small molecule kinase inhibitors of STK33 may be useful to treat KRAS-dependent tumors. In this study, we investigated the role of STK33 in mutant KRAS human cancer cells using RNA interference, dominant mutant overexpression, and small molecule inhibitors. As expected, KRAS downregulation decreased the survival of KRAS-dependent cells. In contrast, STK33 downregulation or dominant mutant overexpression had no effect on KRAS signaling or survival of these cells. Similarly, a synthetic lethal siRNA screen conducted in a broad panel of KRAS wild-type or mutant cells identified KRAS but not STK33 as essential for survival. We also obtained similar negative results using small molecule inhibitors of the STK33 kinase identified by high-throughput screening. Taken together, our findings refute earlier proposals that STK33 inhibition may be a useful therapeutic approach to target human KRAS mutant tumors. ©2011 AACR.

  4. Ibrutinib Inhibits ERBB Receptor Tyrosine Kinases and HER2-Amplified Breast Cancer Cell Growth.

    Science.gov (United States)

    Chen, Jun; Kinoshita, Taisei; Sukbuntherng, Juthamas; Chang, Betty Y; Elias, Laurence

    2016-12-01

    Ibrutinib is a potent, small-molecule Bruton tyrosine kinase (BTK) inhibitor developed for the treatment of B-cell malignancies. Ibrutinib covalently binds to Cys481 in the ATP-binding domain of BTK. This cysteine residue is conserved among 9 other tyrosine kinases, including HER2 and EGFR, which can be targeted. Screening large panels of cell lines demonstrated that ibrutinib was growth inhibitory against some solid tumor cells, including those inhibited by other HER2/EGFR inhibitors. Among sensitive cell lines, breast cancer lines with HER2 overexpression were most potently inhibited by ibrutinib (ibrutinib coincided with downregulation of phosphorylation on HER2 and EGFR and their downstream targets, AKT and ERK. Irreversible inhibition of HER2 and EGFR in breast cancer cells was established after 30-minute incubation above 100 nmol/L or following 2-hour incubation at lower concentrations. Furthermore, ibrutinib inhibited recombinant HER2 and EGFR activity that was resistant to dialysis and rapid dilution, suggesting an irreversible interaction. The dual activity toward TEC family (BTK and ITK) and ERBB family kinases was unique to ibrutinib, as ERBB inhibitors do not inhibit or covalently bind BTK or ITK. Xenograft studies with HER2 + MDA-MB-453 and BT-474 cells in mice in conjunction with determination of pharmacokinetics demonstrated significant exposure-dependent inhibition of growth and key signaling molecules at levels that are clinically achievable. Ibrutinib's unique dual spectrum of activity against both TEC family and ERBB kinases suggests broader applications of ibrutinib in oncology. Mol Cancer Ther; 15(12); 2835-44. ©2016 AACR. ©2016 American Association for Cancer Research.

  5. Long-term Persistence of Innate Lymphoid Cells in the Gut After Intestinal Transplantation.

    Science.gov (United States)

    Weiner, Joshua; Zuber, Julien; Shonts, Brittany; Yang, Suxiao; Fu, Jianing; Martinez, Mercedes; Farber, Donna L; Kato, Tomoaki; Sykes, Megan

    2017-10-01

    Little is known about innate lymphoid cell (ILC) populations in the human gut, and the turnover of these cells and their subsets after transplantation has not been described. Intestinal samples were taken from 4 isolated intestine and 3 multivisceral transplant recipients at the time of any operative resection, such as stoma closure or revision. ILCs were isolated and analyzed by flow cytometry. The target population was defined as being negative for lineage markers and double-positive for CD45/CD127. Cells were further stained to define ILC subsets and a donor-specific or recipient-specific HLA marker to analyze chimerism. Donor-derived ILCs were found to persist greater than 8 years after transplantation. Additionally, the percentage of cells thought to be lymphoid tissue inducer cells among donor ILCs was far higher than that among recipient ILCs. Our findings demonstrate that donor-derived ILCs persist long-term after transplantation and support the notion that human lymphoid tissue inducer cells may form in the fetus and persist throughout life, as hypothesized in rodents. Correlation between chimerism and rejection, graft failure, and patient survival requires further study.

  6. Defining a stem cell hierarchy in the intestine: markers, caveats and controversies

    Science.gov (United States)

    Smith, Nicholas R.; Gallagher, Alexandra C.

    2016-01-01

    Abstract The past decade has appreciated rapid advance in identifying the once elusive intestinal stem cell (ISC) populations that fuel the continual renewal of the epithelial layer. This advance was largely driven by identification of novel stem cell marker genes, revealing the existence of quiescent, slowly‐ and active‐cycling ISC populations. However, a critical barrier for translating this knowledge to human health and disease remains elucidating the functional interplay between diverse stem cell populations. Currently, the precise hierarchical and regulatory relationships between these ISC populations are under intense scrutiny. The classical theory of a linear hierarchy, where quiescent and slowly‐cycling stem cells self‐renew but replenish an active‐cycling population, is well established in other rapidly renewing tissues such as the haematopoietic system. Efforts to definitively establish a similar stem cell hierarchy within the intestinal epithelium have yielded conflicting results, been difficult to interpret, and suggest non‐conventional alternatives to a linear hierarchy. While these new and potentially paradigm‐shifting discoveries are intriguing, the field will require development of a number of critical tools, including highly specific stem cell marker genes along with more rigorous experimental methodologies, to delineate the complex cellular relationships within this dynamic organ system. PMID:26864260

  7. Atractylodes macrocephala Koidz stimulates intestinal epithelial cell migration through a polyamine dependent mechanism.

    Science.gov (United States)

    Song, Hou-Pan; Li, Ru-Liu; Zhou, Chi; Cai, Xiong; Huang, Hui-Yong

    2015-01-15

    Atractylodes macrocephala Koidz (AMK), a valuable traditional Chinese herbal medicine, has been widely used in clinical practice for treating patients with disorders of the digestive system. AMK has shown noteworthy promoting effect on improving gastrointestinal function and immunity, which might represent a promising candidate for the treatment of intestinal mucosa injury. The aim of this study was to investigate the efficacy of AMK on intestinal mucosal restitution and the underlying mechanisms via intestinal epithelial (IEC-6) cell migration model. A cell migration model of IEC-6 cells was induced by a single-edge razor blade along the diameter of the cell layers in six-well polystyrene plates. After wounding, the cells were grown in control cultures and in cultures containing spermidine (5μM, SPD, reference drug), alpha-difluoromethylornithine (2.5mM, DFMO, polyamine inhibitor), AMK (50, 100, and 200mg/L), DFMO plus SPD and DFMO plus AMK for 12h. The polyamines content was detected by high-performance liquid chromatography (HPLC) with pre-column derivatization. The Rho mRNAs expression levels were assessed by Q-RT-PCR. The Rho and non-muscle myosin II proteins expression levels were analyzed by Western blot. The formation and distribution of non-muscle myosin II stress fibers were monitored with immunostaining techniques using specific antibodies and observed by confocal microscopy. Cell migration assay was carried out using inverted microscope and the Image-Pro Plus software. All of these indexes were used to evaluate the effectiveness of AMK. (1) Treatment with AMK caused significant increases in cellular polyamines content and Rho mRNAs and proteins expression levels, as compared to control group. Furthermore, AMK exposure increased non-muscle myosin II protein expression levels and formation of non-muscle myosin II stress fibers, and resulted in an acceleration of cell migration in IEC-6 cells. (2) Depletion of cellular polyamines by DFMO resulted in a

  8. Modulation of Pacemaker Potentials in Murine Small Intestinal Interstitial Cells of Cajal by Gamisoyo-San, a Traditional Chinese Herbal Medicine.

    Science.gov (United States)

    Kim, Doeun; Kim, Jung Nam; Nam, Joo Hyun; Lee, Jong Rok; Kim, Sang Chan; Kim, Byung Joo

    2018-04-19

    The Gamisoyo-san (GSS) has been used for -improving the gastrointestinal (GI) symptoms. The purpose of this study was to investigate the effects of GSS, a traditional Chinese herbal medicine, on the pacemaker potentials of mouse small intestinal interstitial cells of Cajal (ICCs). ICCs from the small intestines were dissociated and cultured. Whole-cell patch-clamp configuration was used to record pacemaker potentials and membrane currents. GSS depolarized ICC pacemaker potentials in a dose-dependent manner. Pretreatment with 4-diphenylacetoxypiperidinium iodide completely inhibited GSS-induced pacemaker potential depolarizations. Intracellular GDP-β-S inhibited GSS-induced effects, and in the presence of U-73122, GSS-induced effects were inhibited. Also, GSS in the presence of a Ca2+-free solution or thapsigargin did not depolarize pacemaker potentials. However, in the presence of calphostin C, GSS slightly depolarized pacemaker potentials. Furthermore, GSS inhibited both transient receptor potential melastatin7 and Ca2+-activated Cl- channel (anoctamin1) currents. GSS depolarized pacemaker potentials of ICCs via G protein and muscarinic M3 receptor signaling pathways and through internal or external Ca2+-, phospholipase C-, and protein kinase C-dependent and transient receptor potential melastatin 7-, and anoctamin 1-independent pathways. The study shows that GSS may regulate GI tract motility, suggesting that GSS could be a basis for developing novel prokinetic agents for treating GI motility dysfunctions. © 2018 S. Karger AG, Basel.

  9. Zinc Supplementation, via GPR39, Upregulates PKCζ to Protect Intestinal Barrier Integrity in Caco-2 Cells Challenged by Salmonella enterica Serovar Typhimurium.

    Science.gov (United States)

    Shao, Yu-Xin; Lei, Zhao; Wolf, Patricia G; Gao, Yan; Guo, Yu-Ming; Zhang, Bing-Kun

    2017-07-01

    Background: Zinc has been shown to improve intestinal barrier function against Salmonella enterica serovar Typhimurium ( S. typhimurium ) infection, but the mechanisms involved in this process remain undefined. Objective: We aimed to explore the roles of G protein-coupled receptor (GPR)39 and protein kinase Cζ (PKCζ) in the regulation by zinc of intestinal barrier function. Methods: A Transwell Caco-2 monolayer was pretreated with 0, 50, or 100 μM Zn and then incubated with S. typhimurium for 0-6 h. Afterward, cells silenced by the small interfering RNA for GPR39 or PKCζ were pretreated with 100 μM Zn and incubated with S. typhimurium for 3 h. Finally, transepithelial electrical resistance (TEER), permeability, tight junction (TJ) proteins, and signaling molecules GPR39 and PKCζ were measured. Results: Compared with controls, S. typhimurium decreased TEER by 62.3-96.2% at 4-6 h ( P 0.1). Silencing GPR39 decreased ( P zinc-activated PKCζ and blocked ( P zinc on epithelial integrity. Furthermore, silencing PKCζ counteracted the protective effect of zinc on epithelial integrity but did not inhibit GPR39 ( P = 0.138). Conclusion: We demonstrated that zinc upregulates PKCζ by activating GPR39 to enhance the abundance of ZO-1, thereby improving epithelial integrity in S. typhimurium- infected Caco-2 cells. © 2017 American Society for Nutrition.

  10. Cell-type-specific activation of mitogen-activated protein kinases in PAN-induced progressive renal disease in rats

    International Nuclear Information System (INIS)

    Park, Sang-Joon; Jeong, Kyu-Shik

    2004-01-01

    We examined the time-course activation and the cell-type specific role of MAP kinases in puromycin aminonucleoside (PAN)-induced renal disease. The maximal activation of c-Jun-NH 2 -terminal kinase (JNK), extracellular signal regulated kinase (ERK), and p38 MAP kinase was detected on Days 52, 38, and 38 after PAN-treatment, respectively. p-JNK was localized in mesangial and proximal tubular cells at the early renal injury. It was expressed, therefore, in the inflammatory cells of tubulointerstitial lesions. While, p-ERK was markedly increased in the glomerular regions and macrophages p-p38 was observed in glomerular endothelial cells, tubular cells, and some inflammatory cells. The results show that the activation of MAP kinases in the early renal injury by PAN-treatment involves cellular changes such as cell proliferation or apoptosis in renal native cells. The activation of MAP kinases in infiltrated inflammatory cells and fibrotic cells plays an important role in destructive events such as glomerulosclerosis and tubulointerstitial fibrosis

  11. Group 3 innate lymphoid cells mediate intestinal selection of commensal bacteria-specific CD4+ T cells

    Science.gov (United States)

    Hepworth, Matthew R.; Fung, Thomas C.; Masur, Samuel H.; Kelsen, Judith R.; McConnell, Fiona M.; Dubrot, Juan; Withers, David R.; Hugues, Stephanie; Farrar, Michael A.; Reith, Walter; Eberl, Gerard; Baldassano, Robert N.; Laufer, Terri M.; Elson, Charles O.; Sonnenberg, Gregory F.

    2015-01-01

    Inflammatory CD4+ T cell responses to self or commensal bacteria underlie the pathogenesis of autoimmunity and inflammatory bowel disease (IBD), respectively. While selection of self-specific T cells in the thymus limits responses to tissue antigens, the mechanisms that control selection of commensal bacteria-specific T cells remain poorly understood. Here we demonstrate that group 3 innate lymphoid cell (ILC3)-intrinsic expression of major histocompatibility complex class II (MHCII) is regulated similarly to thymic epithelial cells, and that MHCII+ ILC3s directly induce cell death of activated commensal bacteria-specific T cells. Further, MHCII on human colonic ILC3s was reduced in pediatric IBD patients. Collectively, these results define a selection pathway for commensal bacteria-specific CD4+ T cells in the intestine, and suggest that this process is dysregulated in human IBD. PMID:25908663

  12. EGFR/Ras Signaling Controls Drosophila Intestinal Stem Cell Proliferation via Capicua-Regulated Genes.

    Directory of Open Access Journals (Sweden)

    Yinhua Jin

    2015-12-01

    Full Text Available Epithelial renewal in the Drosophila intestine is orchestrated by Intestinal Stem Cells (ISCs. Following damage or stress the intestinal epithelium produces ligands that activate the epidermal growth factor receptor (EGFR in ISCs. This promotes their growth and division and, thereby, epithelial regeneration. Here we demonstrate that the HMG-box transcriptional repressor, Capicua (Cic, mediates these functions of EGFR signaling. Depleting Cic in ISCs activated them for division, whereas overexpressed Cic inhibited ISC proliferation and midgut regeneration. Epistasis tests showed that Cic acted as an essential downstream effector of EGFR/Ras signaling, and immunofluorescence showed that Cic's nuclear localization was regulated by EGFR signaling. ISC-specific mRNA expression profiling and DNA binding mapping using DamID indicated that Cic represses cell proliferation via direct targets including string (Cdc25, Cyclin E, and the ETS domain transcription factors Ets21C and Pointed (pnt. pnt was required for ISC over-proliferation following Cic depletion, and ectopic pnt restored ISC proliferation even in the presence of overexpressed dominant-active Cic. These studies identify Cic, Pnt, and Ets21C as critical downstream effectors of EGFR signaling in Drosophila ISCs.

  13. MUC1 (CD227) interacts with lck tyrosine kinase in Jurkat lymphoma cells and normal T cells.

    Science.gov (United States)

    Mukherjee, P; Tinder, T L; Basu, G D; Gendler, S J

    2005-01-01

    MUC1 (CD227) is a large transmembrane epithelial mucin glycoprotein, which is aberrantly overexpressed in most adenocarcinomas and is a target for immune therapy for epithelial tumors. Recently, MUC1 has been detected in a variety of hematopoietic cell malignancies including T and B cell lymphomas and myelomas; however, its function in these cells is not clearly defined. Using the Jurkat T cell lymphoma cell line and normal human T cells, we demonstrate that MUC1 is not only expressed in these cells but is also phosphorylated upon T cell receptor (TCR) ligation and associates with the Src-related T cell tyrosine kinase, p56lck. Upon TCR-mediated activation of Jurkat cells, MUC1 is found in the low-density membrane fractions, where linker of T cell activation is contained. Abrogation of MUC1 expression in Jurkat cells by MUC1-specific small interfering RNA resulted in defects in TCR-mediated downstream signaling events associated with T cell activation. These include reduction in Ca2+ influx and extracellular signal-regulated kinase 1/2 phosphorylation, leading to a decrease in CD69 expression, proliferation, and interleukin-2 production. These results suggest a regulatory role of MUC1 in modulating proximal signal transduction events through its interaction with proteins of the activation complex.

  14. Mapping of HNF4alpha target genes in intestinal epithelial cells

    DEFF Research Database (Denmark)

    Boyd, Mette; Bressendorff, Simon; Moller, Jette

    2009-01-01

    ABSTRACT: BACKGROUND: The role of HNF4alpha has been extensively studied in hepatocytes and pancreatic beta-cells, and HNF4alpha is also regarded as key regulator of intestinal epithelial cell differentiation as well. The aim of the present work is to identify novel HNF4alpha target genes....... The HNF4alpha ChIP-chip data was matched with gene expression and histone H3 acetylation status of the promoters in order to identify HNF4alpha binding to actively transcribed genes with an open chromatin structure. RESULTS: 1,541 genes were identified as potential HNF4alpha targets, many of which have...

  15. A kinase inhibitor screen identifies Mcl-1 and Aurora kinase A as novel treatment targets in antiestrogen-resistant breast cancer cells

    DEFF Research Database (Denmark)

    Thrane, S; Pedersen, A M; Thomsen, M B H

    2015-01-01

    Antiestrogen resistance is a major problem in breast cancer treatment. Therefore, the search for new therapeutic targets and biomarkers for antiestrogen resistance is crucial. In this study, we performed a kinase inhibitor screen on antiestrogen responsive MCF-7 cells and a panel of MCF-7-derived...

  16. RACK1 Targets the Extracellular Signal-Regulated Kinase/Mitogen-Activated Protein Kinase Pathway To Link Integrin Engagement with Focal Adhesion Disassembly and Cell Motility

    Czech Academy of Sciences Publication Activity Database

    Vomastek, Tomáš; Iwanicki, M. P.; Schaeffer, J.; J.; Tarcsafalvi, A.; Parsons, J. T.; Weber, M. J.

    2007-01-01

    Roč. 27, č. 23 (2007), s. 8296-8305 ISSN 0270-7306 R&D Projects: GA AV ČR IAA500200716 Institutional research plan: CEZ:AV0Z50200510 Keywords : protein kinase * adhesion * cell Subject RIV: EE - Microbiology, Virology Impact factor: 6.420, year: 2007

  17. Multilevel dysregulation of STAT3 activation in anaplastic lymphoma kinase-positive T/null-cell lymphoma

    DEFF Research Database (Denmark)

    Zhang, Qian; Raghunath, Puthryaveett N; Xue, Liquan

    2002-01-01

    Accumulating evidence indicates that expression of anaplastic lymphoma kinase (ALK), typically due to t(2;5) translocation, defines a distinct type of T/null-cell lymphoma (TCL). The resulting nucleophosmin (NPM) /ALK chimeric kinase is constitutively active and oncogenic. Downstream effector mol...

  18. HOXB4 Gene Expression Is Regulated by CDX2 in Intestinal Epithelial Cells

    DEFF Research Database (Denmark)

    Jørgensen, Steffen; Coshun, Mehmet; Mikkelsen Homburg, Keld

    2016-01-01