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Sample records for airway mucin secretion

  1. Regulated Mucin Secretion from Airway Epithelial Cells

    PubMed Central

    Adler, Kenneth B.; Tuvim, Michael J.; Dickey, Burton F.

    2013-01-01

    Secretory epithelial cells of the proximal airways synthesize and secrete gel-forming polymeric mucins. The secreted mucins adsorb water to form mucus that is propelled by neighboring ciliated cells, providing a mobile barrier which removes inhaled particles and pathogens from the lungs. Several features of the intracellular trafficking of mucins make the airway secretory cell an interesting comparator for the cell biology of regulated exocytosis. Polymeric mucins are exceedingly large molecules (up to 3 × 106 Da per monomer) whose folding and initial polymerization in the ER requires the protein disulfide isomerase Agr2. In the Golgi, mucins further polymerize to form chains and possibly branched networks comprising more than 20 monomers. The large size of mucin polymers imposes constraints on their packaging into transport vesicles along the secretory pathway. Sugar side chains account for >70% of the mass of mucins, and their attachment to the protein core by O-glycosylation occurs in the Golgi. Mature polymeric mucins are stored in large secretory granules ∼1 μm in diameter. These are translocated to the apical membrane to be positioned for exocytosis by cooperative interactions among myristoylated alanine-rich C kinase substrate, cysteine string protein, heat shock protein 70, and the cytoskeleton. Mucin granules undergo exocytic fusion with the plasma membrane at a low basal rate and a high stimulated rate. Both rates are mediated by a regulated exocytic mechanism as indicated by phenotypes in both basal and stimulated secretion in mice lacking Munc13-2, a sensor of the second messengers calcium and diacylglycerol (DAG). Basal secretion is induced by low levels of activation of P2Y2 purinergic and A3 adenosine receptors by extracellular ATP released in paracrine fashion and its metabolite adenosine. Stimulated secretion is induced by high levels of the same ligands, and possibly by inflammatory mediators as well. Activated receptors are coupled to

  2. VAMP8 is a vesicle SNARE that regulates mucin secretion in airway goblet cells.

    PubMed

    Jones, Lisa C; Moussa, Lama; Fulcher, M Leslie; Zhu, Yunxiang; Hudson, Elizabeth J; O'Neal, Wanda K; Randell, Scott H; Lazarowski, Eduardo R; Boucher, Richard C; Kreda, Silvia M

    2012-02-01

    Mucin secretion is an innate defence mechanism, which is noxiously upregulated in obstructive lung diseases (e.g. chronic obstructive pulmonary disease (COPD), cystic fibrosis and asthma). Mucin granule exocytosis is regulated by specific protein complexes, but the SNARE exocytotic core has not been defined in airway goblet cells. In this study, we identify VAMP8 as one of the SNAREs regulating mucin granule exocytosis. VAMP8 mRNA was present in human airway and lung epithelial cells, and deep-sequencing and expression analyses of airway epithelial cells revealed that VAMP8 transcripts were expressed at 10 times higher levels than other VAMP mRNAs. In human airway epithelial cell cultures and freshly excised tissues, VAMP8 immunolocalised mainly to goblet cell mucin granules. The function of VAMP8 in airway mucin secretion was tested by RNA interference techniques. Both VAMP8 short interfering RNAs (siRNAs) and short hairpin RNAs (shRNAs) reduced mucin secretion induced by PAR agonists, neutrophil elastase and ATP in two airway epithelial cell culture models. Notably, basal (non-agonist elicited) mucin secretion was also reduced in these experiments. VAMP8 knockdown was also effective in decreasing mucin secretion in airway epithelial cell cultures with induced mucous metaplasia/mucin hypersecretion. Unlike VAMP8 silencing, knockdown of VAMP2 or VAMP3 did not affect mucin secretion. Importantly, in VAMP8 knock-out (KO) mice with IL-13-induced mucous metaplasia, mucin content in the bronchoalveolar lavage (BAL) and ATP-stimulated mucin secretion in the trachea were reduced compared to WT-matched littermates. Our data indicate that VAMP8 is an essential SNARE in airway mucin granule exocytosis. Reduction of VAMP8 activity/expression may provide a novel therapeutic target to ameliorate airway mucus obstruction in lung diseases. PMID:22144578

  3. SNAP23 is selectively expressed in airway secretory cells and mediates baseline and stimulated mucin secretion

    PubMed Central

    Ren, Binhui; Azzegagh, Zoulikha; Jaramillo, Ana M.; Zhu, Yunxiang; Pardo-Saganta, Ana; Bagirzadeh, Rustam; Flores, Jose R.; Han, Wei; Tang, Yong-jun; Tu, Jing; Alanis, Denise M.; Evans, Christopher M.; Guindani, Michele; Roche, Paul A.; Rajagopal, Jayaraj; Chen, Jichao; Davis, C. William; Tuvim, Michael J.; Dickey, Burton F.

    2015-01-01

    Airway mucin secretion is important pathophysiologically and as a model of polarized epithelial regulated exocytosis. We find the trafficking protein, SNAP23 (23-kDa paralogue of synaptosome-associated protein of 25 kDa), selectively expressed in secretory cells compared with ciliated and basal cells of airway epithelium by immunohistochemistry and FACS, suggesting that SNAP23 functions in regulated but not constitutive epithelial secretion. Heterozygous SNAP23 deletant mutant mice show spontaneous accumulation of intracellular mucin, indicating a defect in baseline secretion. However mucins are released from perfused tracheas of mutant and wild-type (WT) mice at the same rate, suggesting that increased intracellular stores balance reduced release efficiency to yield a fully compensated baseline steady state. In contrast, acute stimulated release of intracellular mucin from mutant mice is impaired whether measured by a static imaging assay 5 min after exposure to the secretagogue ATP or by kinetic analysis of mucins released from perfused tracheas during the first 10 min of ATP exposure. Together, these data indicate that increased intracellular stores cannot fully compensate for the defect in release efficiency during intense stimulation. The lungs of mutant mice develop normally and clear bacteria and instilled polystyrene beads comparable to WT mice, consistent with these functions depending on baseline secretion that is fully compensated. PMID:26182382

  4. Baseline Goblet Cell Mucin Secretion in the Airways Exceeds Stimulated Secretion over Extended Time Periods, and Is Sensitive to Shear Stress and Intracellular Mucin Stores

    PubMed Central

    Doyle, Sean P.; Nguyen, Kristine; Ribeiro, Carla M. P.; Vasquez, Paula A.; Forest, M. Gregory; Lethem, Michael I.; Dickey, Burton F.; Davis, C. William

    2015-01-01

    Airway mucin secretion studies have focused on goblet cell responses to exogenous agonists almost to the exclusion of baseline mucin secretion (BLMS). In human bronchial epithelial cell cultures (HBECCs), maximal agonist-stimulated secretion exceeds baseline by ~3-fold as measured over hour-long periods, but mucin stores are discharged completely and require 24 h for full restoration. Hence, over 24 h, total baseline exceeds agonist-induced secretion by several-fold. Studies with HBECCs and mouse tracheas showed that BLMS is highly sensitive to mechanical stresses. Harvesting three consecutive 1 h baseline luminal incubations with HBECCs yielded equal rates of BLMS; however, lengthening the middle period to 72 h decreased the respective rate significantly, suggesting a stimulation of BLMS by the gentle washes of HBECC luminal surfaces. BLMS declined exponentially after washing HBECCs (t1/2 = 2.75 h), to rates approaching zero. HBECCs exposed to low perfusion rates exhibited spike-like increases in BLMS when flow was jumped 5-fold: BLMS increased >4 fold, then decreased within 5 min to a stable plateau at 1.5–2-fold over control. Higher flow jumps induced proportionally higher BLMS increases. Inducing mucous hyperplasia in HBECCs increased mucin production, BLMS and agonist-induced secretion. Mouse tracheal BLMS was ~6-fold higher during perfusion, than when flow was stopped. Munc13-2 null mouse tracheas, with their defect of accumulated cellular mucins, exhibited similar BLMS as WT, contrary to predictions of lower values. Graded mucous metaplasia induced in WT and Munc13-2 null tracheas with IL-13, caused proportional increases in BLMS, suggesting that naïve Munc13-2 mouse BLMS is elevated by increased mucin stores. We conclude that BLMS is, [i] a major component of mucin secretion in the lung, [ii] sustained by the mechanical activity of a dynamic lung, [iii] proportional to levels of mucin stores, and [iv] regulated differentially from agonist-induced mucin

  5. Baseline Goblet Cell Mucin Secretion in the Airways Exceeds Stimulated Secretion over Extended Time Periods, and Is Sensitive to Shear Stress and Intracellular Mucin Stores.

    PubMed

    Zhu, Yunxiang; Abdullah, Lubna H; Doyle, Sean P; Nguyen, Kristine; Ribeiro, Carla M P; Vasquez, Paula A; Forest, M Gregory; Lethem, Michael I; Dickey, Burton F; Davis, C William

    2015-01-01

    Airway mucin secretion studies have focused on goblet cell responses to exogenous agonists almost to the exclusion of baseline mucin secretion (BLMS). In human bronchial epithelial cell cultures (HBECCs), maximal agonist-stimulated secretion exceeds baseline by ~3-fold as measured over hour-long periods, but mucin stores are discharged completely and require 24 h for full restoration. Hence, over 24 h, total baseline exceeds agonist-induced secretion by several-fold. Studies with HBECCs and mouse tracheas showed that BLMS is highly sensitive to mechanical stresses. Harvesting three consecutive 1 h baseline luminal incubations with HBECCs yielded equal rates of BLMS; however, lengthening the middle period to 72 h decreased the respective rate significantly, suggesting a stimulation of BLMS by the gentle washes of HBECC luminal surfaces. BLMS declined exponentially after washing HBECCs (t1/2 = 2.75 h), to rates approaching zero. HBECCs exposed to low perfusion rates exhibited spike-like increases in BLMS when flow was jumped 5-fold: BLMS increased >4 fold, then decreased within 5 min to a stable plateau at 1.5-2-fold over control. Higher flow jumps induced proportionally higher BLMS increases. Inducing mucous hyperplasia in HBECCs increased mucin production, BLMS and agonist-induced secretion. Mouse tracheal BLMS was ~6-fold higher during perfusion, than when flow was stopped. Munc13-2 null mouse tracheas, with their defect of accumulated cellular mucins, exhibited similar BLMS as WT, contrary to predictions of lower values. Graded mucous metaplasia induced in WT and Munc13-2 null tracheas with IL-13, caused proportional increases in BLMS, suggesting that naïve Munc13-2 mouse BLMS is elevated by increased mucin stores. We conclude that BLMS is, [i] a major component of mucin secretion in the lung, [ii] sustained by the mechanical activity of a dynamic lung, [iii] proportional to levels of mucin stores, and [iv] regulated differentially from agonist-induced mucin

  6. Coupling of airway ciliary activity and mucin secretion to mechanical stresses by purinergic signaling.

    PubMed

    Davis, C William; Lazarowski, Eduardo

    2008-11-30

    The mucociliary clearance system is comprised of three components, ion transport activities controlling the height of airway surface liquid (ASL), mucin secretion, and ciliary activity. These activities in humans are controlled principally by local agonists, extracellular nucleotides and nucleosides released from the epithelium. Importantly, mechanical stresses stimulate goblet cell mucin secretion, ciliary beating, and Cl- and fluid secretion through mechanically induced nucleotide release. Emerging evidence also implicates co-secretion of nucleotides and mucin from goblet cells as a source of extracellular agonist. At rest, ATP is released onto airway surfaces at approximately 370fmol/mincm2, but only approximately 3% of released ATP is recovered in ASL. Secreted UTP meets with a similar fate. A wide variety of hydrolytic and transphosphorylating ecto-enzymes convert the triphosphate nucleotides into ADP, AMP, and adenosine, UDP, UMP, and uridine. Of these, ATP, adenosine, UTP, and UDP act as agonists at apical P2Y2 (ATP, UTP), P2Y6 (UDP), and A2B (adenosine) receptors on ciliated and/or goblet cells to regulate mucociliary clearance. PMID:18635403

  7. Cystic fibrosis airway secretions exhibit mucin hyperconcentration and increased osmotic pressure

    PubMed Central

    Henderson, Ashley G.; Ehre, Camille; Button, Brian; Abdullah, Lubna H.; Cai, Li-Heng; Leigh, Margaret W.; DeMaria, Genevieve C.; Matsui, Hiro; Donaldson, Scott H.; Davis, C. William; Sheehan, John K.; Boucher, Richard C.; Kesimer, Mehmet

    2014-01-01

    The pathogenesis of mucoinfective lung disease in cystic fibrosis (CF) patients likely involves poor mucus clearance. A recent model of mucus clearance predicts that mucus flow depends on the relative mucin concentration of the mucus layer compared with that of the periciliary layer; however, mucin concentrations have been difficult to measure in CF secretions. Here, we have shown that the concentration of mucin in CF sputum is low when measured by immunologically based techniques, and mass spectrometric analyses of CF mucins revealed mucin cleavage at antibody recognition sites. Using physical size exclusion chromatography/differential refractometry (SEC/dRI) techniques, we determined that mucin concentrations in CF secretions were higher than those in normal secretions. Measurements of partial osmotic pressures revealed that the partial osmotic pressure of CF sputum and the retained mucus in excised CF lungs were substantially greater than the partial osmotic pressure of normal secretions. Our data reveal that mucin concentration cannot be accurately measured immunologically in proteolytically active CF secretions; mucins are hyperconcentrated in CF secretions; and CF secretion osmotic pressures predict mucus layer–dependent osmotic compression of the periciliary liquid layer in CF lungs. Consequently, mucin hypersecretion likely produces mucus stasis, which contributes to key infectious and inflammatory components of CF lung disease. PMID:24892808

  8. Effects of the root of Platycodon grandiflorum on airway mucin hypersecretion in vivo and platycodin D(3) and deapi-platycodin on production and secretion of airway mucin in vitro.

    PubMed

    Ryu, Jiho; Lee, Hyun Jae; Park, Su Hyun; Kim, Jinwoong; Lee, Dongho; Lee, Sang Kook; Kim, Yeong Shik; Hong, Jang-Hee; Seok, Jeong Ho; Lee, Choong Jae

    2014-03-15

    We investigated whether aqueous extract of the root of Platycodon grandiflorum A. de Candolle (APG), platycodinD(3) and deapi-platycodin significantly affect the production and secretion of airway mucin using in vivo and in vitro experimental models. Effect of APG was checked on hypersecretion of pulmonary mucin in sulfur dioxide-induced bronchitis in rats. Confluent NCI-H292 cells were pretreated with platycodinD(3) or deapi-platycodin for 30min and then stimulated with PMA (phorbol 12-myristate 13-acetate) for 24h. The MUC5AC mucin production and secretion were measured by ELISA. The results were as follows: (1) APG stimulated the secretion of airway mucin in sulfur dioxide-induced bronchitis rat model; (2) platycodinD(3) and deapi-platycodin inhibited the production of MUC5AC mucin induced by PMA from NCI-H292 cells, respectively; (3) however, platycodinD(3) and deapi-platycodin did not inhibit but stimulated the secretion of MUC5AC mucin induced by PMA from NCI-H292 cells, respectively. This result suggests that aqueous extract of P. grandiflorum A. de Candolle and the two natural products derived from it, platycodinD(3) and deapi-platycodin, can regulate the production and secretion of airway mucin and, at least in part, explains the traditional use of aqueous extract of P. grandiflorum A. de Candolle as expectorants in diverse inflammatory pulmonary diseases. PMID:24290472

  9. Regulation of Airway Mucin Gene Expression

    PubMed Central

    Thai, Philip; Loukoianov, Artem; Wachi, Shinichiro; Wu, Reen

    2015-01-01

    Mucins are important components that exert a variety of functions in cell-cell interaction, epidermal growth factor receptor signaling, and airways protection. In the conducting airways of the lungs, mucins are the major contributor to the viscoelastic property of mucous secretion, which is the major barrier to trapping inhaled microbial organism, particulates, and oxidative pollutants. The homeostasis of mucin production is an important feature in conducting airways for the maintenance of mucociliary function. Aberrant mucin secretion and accumulation in airway lumen are clinical hallmarks associated with various lung diseases, such as asthma, chronic obstructive pulmonary disease, cystic fibrosis, emphysema, and lung cancer. Among 20 known mucin genes identified, 11 of them have been verified at either the mRNA and/or protein level in airways. The regulation of mucin genes is complicated, as are the mediators and signaling pathways. This review summarizes the current view on the mediators, the signaling pathways, and the transcriptional units that are involved in the regulation of airway mucin gene expression. In addition, we also point out essential features of epigenetic mechanisms for the regulation of these genes. PMID:17961085

  10. Luteolin inhibited the gene expression, production and secretion of MUC5AC mucin via regulation of nuclear factor kappa B signaling pathway in human airway epithelial cells.

    PubMed

    Lee, Hyun Jae; Seo, Hyo-Seok; Ryu, Jiho; Yoon, Yong Pill; Park, Su Hyun; Lee, Choong Jae

    2015-04-01

    Luteolin, a flavonoidal compound derived from Lonicera japonica Thunb. and Chrysanthemum indicum L., has been reported to show anti-inflammatory, anti-oxidative and anti-carcinogenic effects. In this study, we investigated whether luteolin significantly affects the secretion, production and gene expression of airway mucin. Confluent NCI-H292 cells were pretreated with luteolin for 30 min and then stimulated with EGF (epidermal growth factor) or PMA (phorbol 12-myristate 13-acetate) for 24 h or the indicated periods. The MUC5AC mucin gene expression was measured by RT-PCR. Production and secretion of MUC5AC mucin protein were measured by ELISA. To elucidate the action mechanism of luteolin, effect of luteolin on PMA-induced NF-κB signaling pathway was investigated by western blot analysis. The results were as follows: (1) Luteolin inhibited the secretion of MUC5AC mucin protein induced by EGF or PMA; (2) Luteolin inhibited the production of MUC5AC mucin protein and the expression of MUC5AC mucin gene induced by EGF or PMA; (3) Luteolin inhibited PMA-induced phosphorylation and degradation of inhibitory kappa Bα (IκBα); (4) Luteolin inhibited PMA-induced phosphorylation and nuclear translocation of nuclear factor kappa B (NF-κB) p65. This result suggests that luteolin can regulate the secretion, production and gene expression of mucin by acting on airway epithelial cells via regulation of NF-kB signaling pathway. PMID:25285988

  11. P2u purinoceptor regulation of mucin secretion in SPOC1 cells, a goblet cell line from the airways.

    PubMed Central

    Abdullah, L H; Davis, S W; Burch, L; Yamauchi, M; Randell, S H; Nettesheim, P; Davis, C W

    1996-01-01

    The SPOC1 cell, a novel goblet cell line derived from rat trachea, was tested for its ability to exhibit regulated mucin secretion in response to purinergic (P2) agonists. High-molecular mass glycoconjugates (HMMGs) purified by CsCl-density-gradient centrifugation had a buoyant density of 1.45 g/ml. The purified HMMG material exhibited a single major band with an apparent molecular mass of greater than 1000 kDa in SDS/ polyacrylamide gels stained with silver or blotted and stained with soya-bean agglutinin. [3H]HMMG was resistant to proteoglycan-degrading enzymes, but was susceptible to neuraminidase. The HMMG was approx. 91% carbohydrate by weight, and the glycosides were O-linked. The HMMG amino acid composition was enriched in Ser and Thr (sum 27%). Thus SPOC1-cell HMMG possess the characteristics of mucin. Mucin secretion by SPOC1 cells, grown on permeable supports and perfused luminally, was stimulated by ATP, UTP and adenosine 5'-[gamma-thio]triphosphate (100 microM) 4-5-fold over a baseline of 4 ng/min. The three dose-effect relations were nearly identical (K0.5 approximately 4 microM). SPOC1 cells grown on plastic and rat tracheal epithelial primary cells responded similarly to ATP and/or UTP. SPOC1 cells failed to respond to other purinergic agonists, either luminally or serosally, and consequently seem to possess an apical membrane P2u purinoceptor. SPOC1-cell total RNA was probed for P2u purinoceptor mRNA. Using conserved primers for both reverse transcriptase and PCR, a single band of the predicted size was observed, which had a nucleotide base sequence identical with the rat P2u purinoceptor mRNA. Thus SPOC1 cells secrete mucin under the control of a P2u purinoceptor; they should prove useful in dissecting the associated cellular regulatory pathways. PMID:8670174

  12. Influenza A induces the major secreted airway mucin MUC5AC in a protease-EGFR-extracellular regulated kinase-Sp1-dependent pathway.

    PubMed

    Barbier, Diane; Garcia-Verdugo, Ignacio; Pothlichet, Julien; Khazen, Roxana; Descamps, Delphyne; Rousseau, Karine; Thornton, David; Si-Tahar, Mustapha; Touqui, Lhousseine; Chignard, Michel; Sallenave, Jean-Michel

    2012-08-01

    Mucins, the main glycoproteins present within mucus, modulate the rheologic properties of airways and participate in lung defense. They are thought to be able to trap and eliminate microorganisms from the lung. Among the mucins secreted in the lung, MUC5AC is the most prominent factor secreted by surface epithelial cells. Although much is known about the signaling pathways involved in the regulation of MUC5AC by host factors such as cytokines or proteases, less is known about the pathways triggered by microorganisms and, specifically, by influenza A virus (IAV). We therefore set up experiments to dissect the molecular mechanisms responsible for the potential modulation of MUC5AC by IAV. Using epithelial cells, C57/Bl6 mice, and IAV strains, we measured MUC5AC expression at the RNA and protein levels, specificity protein 1 (Sp1) activation, and protease activity. Intermediate molecular partners were confirmed using pharmacological inhibitors, blocking antibodies, and small interfering (si)RNAs. We showed in vitro and in vivo that IAV up-regulates epithelial cell-derived MUC5AC and Muc5ac expression in mice, both at transcriptional (through the induction of Sp1) and translational levels. In addition, we determined that this induction was dependent on a protease-epithelial growth factor receptor-extracellular regulated kinase-Sp1 signaling cascade, involving in particular the human airway trypsin. Our data point to MUC5AC as a potential modulatory mechanism by which the lung epithelia respond to IAV infection, and we dissect, for the first time to the best of our knowledge, the molecular partners involved. Future experiments using MUC5AC-targeted strategies should help further unravel the pathophysiological consequences of IAV-induced MUC5AC expression for lung homeostasis. PMID:22383584

  13. Regulation of mucin secretion from in vitro cellular models.

    PubMed

    Davis, C William

    2002-01-01

    Conceptually, in vitro models for airway mucin secretion may provide useful information pertinent to many aspects of goblet cell biology/physiology. Such models may be especially useful in identifying potential secretagogues, probing the distribution of receptors between goblet cell apical and basolateral membrane domains, and revealing intracellular messenger pathways underlying receptor activation. We have focused most recently on human bronchial epithelial cell cultures grown as tracheal xenografts and SPOC1 cell cultures. These two models are remarkably similar with respect to the regulation of mucin secretion: luminal challenges with the P2Y2 purinoceptor agonists ATP or UTP elicit mucin secretion with EC50s of about 3 microM and archetypal agonists to other purinoceptors test negative. P2Y2 purinoceptors typically couple via Gq to phospholipase C, suggesting that intracellular Ca2+ and protein kinase C (PKC) are important in activating intracellular pathways leading to goblet cell mucin release. Consistent with this notion, phorbol myristate acetate and ionomycin elicit mucin secretion from SPOC1 cells and HBE xenografts, whereas cyclic nucleotides do not. Delineation of the molecules comprising these receptor/messenger interactions and their supporting pathways remains an important challenge for the development of drugs effective in therapeutic interventions in mucin hypersecretory airway diseases; with these models we have initiated the process. PMID:12568491

  14. The buffer capacity of airway epithelial secretions

    PubMed Central

    Kim, Dusik; Liao, Jie; Hanrahan, John W.

    2014-01-01

    The pH of airway epithelial secretions influences bacterial killing and mucus properties and is reduced by acidic pollutants, gastric reflux, and respiratory diseases such as cystic fibrosis (CF). The effect of acute acid loads depends on buffer capacity, however the buffering of airway secretions has not been well characterized. In this work we develop a method for titrating micro-scale (30 μl) volumes and use it to study fluid secreted by the human airway epithelial cell line Calu-3, a widely used model for submucosal gland serous cells. Microtitration curves revealed that HCO−3 is the major buffer. Peak buffer capacity (β) increased from 17 to 28 mM/pH during forskolin stimulation, and was reduced by >50% in fluid secreted by cystic fibrosis transmembrane conductance regulator (CFTR)-deficient Calu-3 monolayers, confirming an important role of CFTR in HCO−3 secretion. Back-titration with NaOH revealed non-volatile buffer capacity due to proteins synthesized and released by the epithelial cells. Lysozyme and mucin concentrations were too low to buffer Calu-3 fluid significantly, however model titrations of porcine gastric mucins at concentrations near the sol-gel transition suggest that mucins may contribute to the buffer capacity of ASL in vivo. We conclude that CFTR-dependent HCO−3 secretion and epithelially-derived proteins are the predominant buffers in Calu-3 secretions. PMID:24917822

  15. Tear Film Mucins: Front Line Defenders of the Ocular Surface; Comparison with Airway and Gastrointestinal Tract Mucins

    PubMed Central

    Hodges, Robin R.; Dartt, Darlene A.

    2014-01-01

    The ocular surface including the cornea and conjunctiva and its overlying tear film are the first tissues of the eye to interact with the external environment. The tear film is complex containing multiple layers secreted by different glands and tissues. Each layer contains specific molecules and proteins that not only maintain the health of the cells on the ocular surface by providing nourishment and removal of waste products but also protect these cells from environment. A major protective mechanism that the corneal and conjunctival cells have developed is secretion of the innermost layer of the tear film, the mucous layer. Both the cornea and conjunctiva express membrane spanning mucins, whereas the conjunctiva also produces soluble mucins. The mucins present in the tear film serve to maintain the hydration of the ocular surface and to provide lubrication and anti-adhesive properties between the cells of the ocular surface and conjunctiva during the blink. A third function is to contribute to the epithelial barrier to prevent pathogens from binding to the ocular surface. This review will focus on the different types of mucins produced by the corneal and conjunctival epithelia. Also included in this review will be a presentation of the structure of mucins, regulation of mucin production, role of mucins in ocular surface diseases, and the differences in mucin production by the ocular surface, airways and gastrointestinal tract. PMID:23954166

  16. Cross-species immunoreactivity of airway mucin as revealed by monoclonal antibodies directed against mucins from human, hamster, and rat.

    PubMed

    Shin, C Y; Lee, W J; Kim, D J; Park, C S; Choi, E Y; Ko, K H

    2000-10-01

    Airway mucin plays crucial role in host-defense and has been implicated in pathophysiology of various airway diseases including asthma and cystic fibrosis. The analysis of airway mucin has been hampered mostly by the lack of specific and efficient methods for the detection of mucin. Recent production of antibodies against airway mucin from several species and also the development of immunoassay procedures make it more efficient to study the airway mucin. However, the cross-species immunoreactivity of antibodies against airway mucin has not been clearly demonstrated and this prompted us to investigate the cross-species immunoreactivity of monoclonal antibodies against human (HM02), hamster (HTA), and rat airway mucin (RT03), which is three most widely used species in the study of mucin. All the monoclonal antibodies (MAbs) used in this study is IgM isotype and recognizes N-acetyl-galactosamine-linked carbohydrate core or backbone portion of airway mucin. In enzyme-linked immunoadsorbent assay (ELISA), Western blot, immunoprecipitation, and immunohistochemical staining experiments, it was demonstrated that human and hamster airway mucin showed strong cross-species immunoreactivity. However, rat airway mucin did not show any cross-species immunoreactivity against human and hamster airway mucin. Endotoxin-induced secretory cell metaplasia and hence the increase in mucin release from hamster airway mucin could be detected with antibodies against hamster and human airway mucin in vivo and in vitro. However, the same increase from rat airway could only be detected with antibody against rat airway mucin but not with antibodies against human and hamster airway mucin. In addition, the increase in mucin release from asthmatic patients could be detected with antibodies against human and hamster airway mucin but not with the antibody against rat airway mucin. The data from the present study implicates that the carbohydrate chain of human and hamster airway mucin, but not that

  17. Heterogeneity of airways mucus: variations in the amounts and glycoforms of the major oligomeric mucins MUC5AC and MUC5B.

    PubMed Central

    Kirkham, Sara; Sheehan, John K; Knight, David; Richardson, Paul S; Thornton, David J

    2002-01-01

    Respiratory mucus contains a mixture of gel-forming mucins but the functional significance of these different mucin species is unknown. To help gain a better understanding of mucus in airways we therefore need to ascertain the concentration of each of the gel-forming mucins within respiratory secretions. Thus the aim of this study was to determine the amounts of specific gel-forming mucins directly from solubilized secretions of the airways and purified mucin preparations. We investigated the feasibility of using direct-binding ELISA employing mucin-specific antisera but were unable to obtain reliable data owing to interference with the immobilization of the mucins on the assay surface by 6 M urea and high levels of non-mucin proteins. We therefore developed an alternative approach based on quantitative Western blotting after agarose-gel electrophoresis, which was not subject to these problems. Here we demonstrate that this procedure provides reliable and reproducible data and have employed it to determine the amounts of the MUC2, MUC5AC and MUC5B mucins in saline-induced sputa from healthy airways and spontaneous sputa from asthmatic airways. Additionally we have used this procedure to analyse these glycoproteins in mucin preparations purified from cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) mucus. Our findings indicate that MUC5AC and MUC5B are the major oligomeric mucins and that airways mucus contains variable amounts of these glycoproteins. By contrast, the MUC2 mucin comprised, at most, only 2.5% of the weight of the gel-forming mucins, indicating that MUC2 is a minor component in sputum. Finally, we show that the amounts and glycosylated variants of the MUC5AC and MUC5B mucins can be altered significantly in diseased airways with, for instance, an increase in the low-charge form of the MUC5B mucin in CF and COPD mucus. PMID:11802783

  18. Secretory Phospholipases A2 Are Secreted From Ciliated Cells and Increase Mucin and Eicosanoid Secretion From Goblet Cells

    PubMed Central

    Shimokawaji, Tadasuke; Kanoh, Soichiro; Rubin, Bruce K.

    2015-01-01

    BACKGROUND: Secretory phospholipases A2 (sPLA2) initiate the biosynthesis of eicosanoids, are increased in the airways of people with severe asthma, and induce mucin hypersecretion. We used IL-13-transformed, highly enriched goblet cells and differentiated (ciliary cell-enriched) human bronchial epithelial cell culture to evaluate the relative contribution of ciliated and goblet cells to airway sPLA2 generation and response. We wished to determine the primary source(s) of sPLA2 and leukotrienes in human airway epithelial cells. METHODS: Human bronchial epithelial cells from subjects without lung disease were differentiated to a ciliated-enriched or goblet-enriched cell phenotype. Synthesis of sPLA2, cysteinyl leukotrienes (cysLTs), and airway mucin messenger RNA and protein was measured by real-time-polymerase chain reaction and an enzyme-linked immunosorbent assay, and the localization of mucin and sPLA2 to specific cells types was confirmed by confocal microscopy. RESULTS: sPLA2 group IIa, V, and X messenger RNA expression was increased in ciliated-enriched cells (P < .001) but not in goblet-enriched cells. sPLA2 were secreted from the apical (air) side of ciliated-enriched cells but not goblet-enriched cells (P < .001). Immunostaining of sPLA2 V was strongly positive in ciliated-enriched cells but not in goblet-enriched cells. sPLA2 released cysLTs from goblet-enriched cells but not from ciliated-enriched cells, and this result was greatest with sPLA2 V (P < .05). sPLA2 V increased goblet-enriched cell mucin secretion, which was inhibited by inhibitors of lipoxygenase or cyclooxygenase (P < .02). CONCLUSIONS: sPLA2 are secreted from ciliated cells and appear to induce mucin and cysLT secretion from goblet cells, strongly suggesting that airway goblet cells are proinflammatory effector cells. PMID:25429648

  19. FLUID SECRETION BY SUBMUCOSAL GLANDS OF THE TRACHEOBRONCHIAL AIRWAYS

    PubMed Central

    Ballard, Stephen T.; Spadafora, Domenico

    2009-01-01

    Submucosal glands of the tracheobronchial airways provide the important functions of secreting mucins, antimicrobial substances, and fluid. This review focuses on the ionic mechanism and regulation of gland fluid secretion and examines the possible role of gland dysfunction in the lethal disease cystic fibrosis (CF). The fluid component of gland secretion is driven by the active transepithelial secretion of both Cl− and HCO3− by serous cells. Gland fluid secretion is neurally regulated with acetylcholine, substance P, and vasoactive intestinal peptide (VIP) playing prominent roles. The cystic fibrosis transmembrane conductance regulator (CFTR) is present in the apical membrane of gland serous cells and mediates the VIP-induced component of liquid secretion whereas the muscarinic component of liquid secretion appears to be at least partially CFTR-independent. Loss of CFTR function, which occurs in CF disease, reduces the capacity of glands to secrete fluid but not mucins. The possible links between the loss of fluid secretion capability and the complex airway pathology of CF are discussed. PMID:17707699

  20. Mycoplasma pneumoniae Modulates STAT3-STAT6/EGFR-FOXA2 Signaling To Induce Overexpression of Airway Mucins

    PubMed Central

    Hao, Yonghua; Kuang, Zhizhou; Jing, Jia; Miao, Jinfeng; Mei, Li Yu; Lee, Ryan J.; Kim, Susie; Choe, Shawn; Krause, Duncan C.

    2014-01-01

    Aberrant mucin secretion and accumulation in the airway lumen are clinical hallmarks associated with various lung diseases such as asthma, chronic obstructive pulmonary disease, and cystic fibrosis. Mycoplasma pneumoniae, long appreciated as one of the triggers of acute exacerbations of chronic pulmonary diseases, has recently been reported to promote excessive mucus secretion. However, the mechanism of mucin overproduction induced by M. pneumoniae remains unclear. This study aimed to determine the mechanism by which M. pneumoniae induces mucus hypersecretion by using M. pneumoniae infection of mouse lungs, human primary bronchial epithelial (NHBE) cells cultured at the air-liquid interface, and the conventionally cultured airway epithelial NCI-H292 cell line. We demonstrated that M. pneumoniae induced the expression of mucins MUC5AC and MUC5B by activating the STAT6-STAT3 and epidermal growth factor receptor (EGFR) signal pathways, which in turn downregulated FOXA2, a transcriptional repressor of mucin biosynthesis. The upstream stimuli of these pathways, including interleukin-4 (IL-4), IL-6, and IL-13, increased dramatically upon exposure to M. pneumoniae. Inhibition of the STAT6, STAT3, and EGFR signaling pathways significantly restored the expression of FOXA2 and attenuated the expression of airway mucins MUC5AC and MUC5B. Collectively, these studies demonstrated that M. pneumoniae induces airway mucus hypersecretion by modulating the STAT/EGFR-FOXA2 signaling pathways. PMID:25287927

  1. Effect of guaifenesin on mucin production, rheology, and mucociliary transport in differentiated human airway epithelial cells.

    PubMed

    Seagrave, JeanClare; Albrecht, Helmut; Park, Yong Sung; Rubin, Bruce; Solomon, Gail; Kim, K Chul

    2011-12-01

    Guaifenesin is widely used to alleviate symptoms of excessive mucus accumulation in the respiratory tract. However, its mechanism of action is poorly understood. The authors hypothesized that guaifenesin improves mucociliary clearance in humans by reducing mucin release, by decreasing mucus viscoelasticity, and by increasing mucociliary transport. To test these hypotheses, human differentiated airway epithelial cells, cultured at an air-liquid interface, were treated with clinically relevant concentrations of guaifenesin by addition to the basolateral medium. To evaluate the effect on mucin secretion, the authors used an anzyme-linked immunosorbent assay (ELISA) to measure the amounts of MUC5AC protein in apical surface fluid and cell lysates. To measure mucociliary transportability, additional cultures were treated for 1 or 6 hours with guaifenesin, and the movement of cell debris was measured from video data. Further, the authors measured mucus dynamic viscoelasticity using a micro cone and plate rheometer with nondestructive creep transformation. Guaifenesin suppressed mucin production in a dose-dependent manner at clinically relevant concentrations. The reduced mucin production was associated with increased mucociliary transport and decreased viscoelasticity of the mucus. Viability of the cultures was not significantly affected. These results suggest that guaifenesin could improve mucociliary clearance in humans by reducing the release and/or production of mucins, thereby altering mucus rheology. PMID:22044398

  2. Noninvasive clearance of airway secretions.

    PubMed

    Hardy, K A; Anderson, B D

    1996-06-01

    Airway clearance techniques are indicated for specific diseases that have known clearance abnormalities (Table 2). Murray and others have commented that such techniques are required only for patients with a daily sputum production of greater than 30 mL. The authors have observed that patients with diseases known to cause clearance abnormalities can have sputum clearance with some techniques, such as positive expiratory pressure, autogenic drainage, and active cycle of breathing techniques, when PDPV has not been effective. Hasani et al has shown that use of the forced exhalatory technique in patients with nonproductive cough still resulted in movement of secretions proximally from all regions of the lung in patients with airway obstruction. It is therefore reasonable to consider airway clearance techniques for any patient who has a disease known to alter mucous clearance, including CF, dyskinetic cilia syndromes, and bronchiectasis from any cause. Patients with atelectasis from mucous plugs and hypersecretory states, such as asthma and chronic bronchitis, patients with pain secondary to surgical procedures, and patients with neuromuscular disease, weak cough, and abnormal patency of the airway may also benefit from the application of airway clearance techniques. Infants and children up to 3 years of age with airway clearance problems need to be treated with PDPV. Manual percussion with hands alone or a flexible face mask or cup and small mechanical vibrator/percussors, such as the ultrasonic devices, can be used. The intrapulmonary percussive ventilator shows growing promise in this area. The high-frequency oscillator is not supplied with vests of appropriate sizes for tiny babies and has not been studied in this group. Young patients with neuromuscular disease may require assisted ventilation and airway oscillations can be applied. CPAP alone has been shown to improve achievable flow rates that will increase air-liquid interactions for patients with these diseases

  3. Effect of dexamethasone and ACC on bacteria-induced mucin expression in human airway mucosa.

    PubMed

    Hauber, Hans-Peter; Goldmann, Torsten; Vollmer, Ekkehard; Wollenberg, Barbara; Zabel, Peter

    2007-11-01

    Gram-negative bacteria can stimulate mucin production, but excessive mucus supports bacterial infection and consequently leads to airway obstruction. Therefore, the effect of dexamethasone (DEX) and the antioxidant acetyl-cysteine (ACC) on bacteria-induced mucus expression was investigated. Explanted human airway mucosa and mucoepidermoid cells (Calu-3) were stimulated with lipopolysaccharide (LPS) or PAM3 (a synthetic lipoprotein). DEX or ACC were added to either LPS- or PAM3-stimulated airway mucosa or Calu-3 cells. Mucin mRNA expression (MUC5AC) and total mucus glycoconjugates (mucin protein) were quantified using real-time PCR and periodic acid Schiff staining. LPS and PAM3 significantly increased mucin expression in airway mucosa and Calu-3 cells (P < 0.05). DEX alone had no significant effect on mucin expression in airway mucosa or Calu-3 cells (P > 0.05). In contrast, DEX significantly reduced LPS- and PAM3-induced mucin expression in explanted mucosal tissue and mucin expression in Calu-3 cells (P < 0.05). In explanted human airway mucosa ACC alone significantly increased mucin expression (P < 0.05). In contrast, ACC significantly decreased LPS- and PAM3-induced mucin expression (P < 0.05). In Calu-3 cells ACC alone had no significant effect on mucin expression (P > 0.05). ACC decreased LPS- and PAM3-induced mucin expression, but this effect was not significant (P > 0.05). These data suggest that DEX can effectively reduce bacteria-induced mucin expression in the airways. ACC alone may increase mucin expression in noninfected mucosa, but it decreased bacteria-induced mucin expression. Further studies are warranted to evaluate whether the effect of DEX or ACC is clinically relevant. PMID:17600317

  4. Parasympathetic and sympathetic regulation of secretion from submucosal glands in airways.

    PubMed

    Nadel, J A; Davis, B

    1980-11-01

    We developed methods to study secretions from airway submucosal glands in vivo: micropipettes with tips specially designed to seal around individual gland duct openings allowed us to collect all of the fluid secreted from individual glands. We visualized the secretions from large numbers of glands simultaneously by coating the airway surface with powdered tantalum; secreted mucus formed "hillocks" over each gland duct opening. Measurement of hillock size provided an estimate of secretion rate. We modified the "hillocks" method to study tracheal glands in vitro. To study regulation of mucin secretion in vitro, we measured the radioactivity from 35S bound to mucins secreted from the luminal surface of pieces of trachea mounted in Using-type chambers. Using these techniques, we demonstrated both cholinergic and alpha-adrenergic regulation of the glands. PMID:7428952

  5. Site of Fluid Secretion in Small Airways.

    PubMed

    Flores-Delgado, Guillermo; Lytle, Christian; Quinton, Paul M

    2016-03-01

    The secretion and management of readily transportable airway surface liquid (ASL) along the respiratory tract is crucial for the clearance of debris and pathogens from the lungs. In proximal large airways, submucosal glands (SMGs) can produce ASL. However, in distal small airways, SMGs are absent, although the lumens of these airways are, uniquely, highly plicated. Little is known about the production and maintenance of ASL in small airways, but using electrophysiology, we recently found that native porcine small airways simultaneously secrete and absorb. How these airways can concurrently transport ASL in opposite directions is puzzling. Using high expression of the Na-K-2Cl cotransport (NKCC) 1 protein (SLC12a2) as a phenotypic marker for fluid secretory cells, immunofluorescence microscopy of porcine small airways revealed two morphologically separated sets of luminal epithelial cells. NKCC1 was abundantly expressed by most cells in the contraluminal regions of the pleats but highly expressed very infrequently by cells in the luminal folds of the epithelial plications. In larger proximal airways, the acini of SMGs expressed NKCC1 prominently, but cells expressing NKCC1 in the surface epithelium were sparse. Our findings indicate that, in the small airway, cells in the pleats of the epithelium secrete ASL, whereas, in the larger proximal airways, SMGs mainly secrete ASL. We propose a mechanism in which the locations of secretory cells in the base of pleats and of absorptive cells in luminal folds physically help maintain a constant volume of ASL in small airways. PMID:26562629

  6. Pseudomonas aeruginosa pyocyanin modulates mucin glycosylation with sialyl-Lewis(x) to increase binding to airway epithelial cells.

    PubMed

    Jeffries, J L; Jia, J; Choi, W; Choe, S; Miao, J; Xu, Y; Powell, R; Lin, J; Kuang, Z; Gaskins, H R; Lau, G W

    2016-07-01

    Cystic fibrosis (CF) patients battle life-long pulmonary infections with the respiratory pathogen Pseudomonas aeruginosa (PA). An overabundance of mucus in CF airways provides a favorable niche for PA growth. When compared with that of non-CF individuals, mucus of CF airways is enriched in sialyl-Lewis(x), a preferred binding receptor for PA. Notably, the levels of sialyl-Lewis(x) directly correlate with infection severity in CF patients. However, the mechanism by which PA causes increased sialylation remains uncharacterized. In this study, we examined the ability of PA virulence factors to modulate sialyl-Lewis(x) modification in airway mucins. We found pyocyanin (PCN) to be a potent inducer of sialyl-Lewis(x) in both mouse airways and in primary and immortalized CF and non-CF human airway epithelial cells. PCN increased the expression of C2/4GnT and ST3Gal-IV, two of the glycosyltransferases responsible for the stepwise biosynthesis of sialyl-Lewis(x), through a tumor necrosis factor (TNF)-α-mediated phosphoinositol-specific phospholipase C (PI-PLC)-dependent pathway. Furthermore, PA bound more efficiently to airway epithelial cells pre-exposed to PCN in a flagellar cap-dependent manner. Importantly, antibodies against sialyl-Lewis(x) and anti-TNF-α attenuated PA binding. These results indicate that PA secretes PCN to induce a favorable environment for chronic colonization of CF lungs by increasing the glycosylation of airway mucins with sialyl-Lewis(x). PMID:26555707

  7. Pseudomonas aeruginosa pyocyanin modulates mucin glycosylation with sialyl-Lewisx to increase binding to airway epithelial cells

    PubMed Central

    Choi, Woosuk; Choe, Shawn; Miao, Jinfeng; Xu, Ying; Powell, Rebecca; Lin, Jingjun; Kuang, Zhizhou; Gaskins, H Rex; Lau, Gee W.

    2015-01-01

    Cystic fibrosis (CF) patients battle life-long pulmonary infections with the respiratory pathogen Pseudomonas aeruginosa (PA). An overabundance of mucus in CF airways provides a favorable niche for PA growth. When compared to that of non-CF individuals, mucus of CF airways is enriched in sialyl-Lewisx, a preferred binding receptor for PA. Notably, the levels of sialyl-Lewisx directly correlate with infection severity in CF patients. However, the mechanism by which PA causes increased sialylation remains uncharacterized. In this study, we examined the ability of PA virulence factors to modulate sialyl-Lewisx modification in airway mucins. We found pyocyanin (PCN) to be a potent inducer of sialyl-Lewisx in both mouse airways and in primary and immortalized CF and non-CF human airway epithelial cells. PCN increased the expression of C2/4GnT and ST3Gal-IV, two of the glycosyltransferases responsible for the stepwise biosynthesis of sialyl-Lewisx, through a TNF-α-mediated phosphoinositol-specific phospholipase C (PI-PLC) dependent pathway. Furthermore, PA bound more efficiently to airway epithelial cells pre-exposed to PCN through a flagellar cap-dependent manner. Importantly, antibodies against sialyl-Lewisx and anti-TNF-α attenuated PA binding. These results indicate that PCN secretes PCN to induce a favorable environment for chronic colonization of CF lungs by increasing the glycosylation of airway mucins with sialyl-Lewisx. PMID:26555707

  8. Excess Secretion of Gel-Forming Mucins and Associated Innate Defense Proteins with Defective Mucin Un-Packaging Underpin Gallbladder Mucocele Formation in Dogs.

    PubMed

    Kesimer, Mehmet; Cullen, John; Cao, Rui; Radicioni, Giorgia; Mathews, Kyle G; Seiler, Gabriela; Gookin, Jody L

    2015-01-01

    Mucosal protection of the gallbladder is vital yet we know very little about the mechanisms involved. In domestic dogs, an emergent syndrome referred to as gallbladder mucocele formation is characterized by excessive secretion of abnormal mucus that results in obstruction and rupture of the gallbladder. The cause of gallbladder mucocele formation is unknown. In these first mechanistic studies of this disease, we investigated normal and mucocele-forming dog gallbladders to determine the source, identity, biophysical properties, and protein associates of the culprit mucins with aim to identify causes for abnormal mucus behavior. We established that mucocele formation involves an adoptive excess secretion of gel forming mucins with abnormal properties by the gallbladder epithelium. The mucus is characterized by a disproportionally significant increase in Muc5ac relative to Muc5b, defective mucin un-packaging, and mucin-interacting innate defense proteins that are capable of dramatically altering the physical and functional properties of mucus. These findings provide an explanation for abnormal mucus behavior and based on similarity to mucus observed in the airways of people with cystic fibrosis, suggest that abnormal mechanisms for maintenance of gallbladder epithelial hydration may be an instigating factor for mucocele formation in dogs. PMID:26414376

  9. Excess Secretion of Gel-Forming Mucins and Associated Innate Defense Proteins with Defective Mucin Un-Packaging Underpin Gallbladder Mucocele Formation in Dogs

    PubMed Central

    Kesimer, Mehmet; Cullen, John; Cao, Rui; Radicioni, Giorgia; Mathews, Kyle G.; Seiler, Gabriela; Gookin, Jody L.

    2015-01-01

    Mucosal protection of the gallbladder is vital yet we know very little about the mechanisms involved. In domestic dogs, an emergent syndrome referred to as gallbladder mucocele formation is characterized by excessive secretion of abnormal mucus that results in obstruction and rupture of the gallbladder. The cause of gallbladder mucocele formation is unknown. In these first mechanistic studies of this disease, we investigated normal and mucocele-forming dog gallbladders to determine the source, identity, biophysical properties, and protein associates of the culprit mucins with aim to identify causes for abnormal mucus behavior. We established that mucocele formation involves an adoptive excess secretion of gel forming mucins with abnormal properties by the gallbladder epithelium. The mucus is characterized by a disproportionally significant increase in Muc5ac relative to Muc5b, defective mucin un-packaging, and mucin-interacting innate defense proteins that are capable of dramatically altering the physical and functional properties of mucus. These findings provide an explanation for abnormal mucus behavior and based on similarity to mucus observed in the airways of people with cystic fibrosis, suggest that abnormal mechanisms for maintenance of gallbladder epithelial hydration may be an instigating factor for mucocele formation in dogs. PMID:26414376

  10. Evidence and Role for Bacterial Mucin Degradation in Cystic Fibrosis Airway Disease

    PubMed Central

    Flynn, Jeffrey M.; Niccum, David; Dunitz, Jordan M.

    2016-01-01

    Chronic lung infections in cystic fibrosis (CF) patients are composed of complex microbial communities that incite persistent inflammation and airway damage. Despite the high density of bacteria that colonize the lower airways, nutrient sources that sustain bacterial growth in vivo, and how those nutrients are derived, are not well characterized. In this study, we examined the possibility that mucins serve as an important carbon reservoir for the CF lung microbiota. While Pseudomonas aeruginosa was unable to efficiently utilize mucins in isolation, we found that anaerobic, mucin-fermenting bacteria could stimulate the robust growth of CF pathogens when provided intact mucins as a sole carbon source. 16S rRNA sequencing and enrichment culturing of sputum also identified that mucin-degrading anaerobes are ubiquitous in the airways of CF patients. The collective fermentative metabolism of these mucin-degrading communities in vitro generated amino acids and short chain fatty acids (propionate and acetate) during growth on mucin, and the same metabolites were also found in abundance within expectorated sputum. The significance of these findings was supported by in vivo P. aeruginosa gene expression, which revealed a heightened expression of genes required for the catabolism of propionate. Given that propionate is exclusively derived from bacterial fermentation, these data provide evidence for an important role of mucin fermenting bacteria in the carbon flux of the lower airways. More specifically, microorganisms typically defined as commensals may contribute to airway disease by degrading mucins, in turn providing nutrients for pathogens otherwise unable to efficiently obtain carbon in the lung. PMID:27548479

  11. Evidence and Role for Bacterial Mucin Degradation in Cystic Fibrosis Airway Disease.

    PubMed

    Flynn, Jeffrey M; Niccum, David; Dunitz, Jordan M; Hunter, Ryan C

    2016-08-01

    Chronic lung infections in cystic fibrosis (CF) patients are composed of complex microbial communities that incite persistent inflammation and airway damage. Despite the high density of bacteria that colonize the lower airways, nutrient sources that sustain bacterial growth in vivo, and how those nutrients are derived, are not well characterized. In this study, we examined the possibility that mucins serve as an important carbon reservoir for the CF lung microbiota. While Pseudomonas aeruginosa was unable to efficiently utilize mucins in isolation, we found that anaerobic, mucin-fermenting bacteria could stimulate the robust growth of CF pathogens when provided intact mucins as a sole carbon source. 16S rRNA sequencing and enrichment culturing of sputum also identified that mucin-degrading anaerobes are ubiquitous in the airways of CF patients. The collective fermentative metabolism of these mucin-degrading communities in vitro generated amino acids and short chain fatty acids (propionate and acetate) during growth on mucin, and the same metabolites were also found in abundance within expectorated sputum. The significance of these findings was supported by in vivo P. aeruginosa gene expression, which revealed a heightened expression of genes required for the catabolism of propionate. Given that propionate is exclusively derived from bacterial fermentation, these data provide evidence for an important role of mucin fermenting bacteria in the carbon flux of the lower airways. More specifically, microorganisms typically defined as commensals may contribute to airway disease by degrading mucins, in turn providing nutrients for pathogens otherwise unable to efficiently obtain carbon in the lung. PMID:27548479

  12. Mechanophysical Stimulations of Mucin Secretion in Cultures of Nasal Epithelial Cells

    PubMed Central

    Even-Tzur Davidovich, Nurit; Kloog, Yoel; Wolf, Michael; Elad, David

    2011-01-01

    Nasal epithelial cells secret mucins and are exposed in vivo to airflow-induced mechanophysical stresses, including wall shear stress (WSS), temperature, and humidity. In this work, human nasal epithelial cells cultured under air-liquid interface conditions were subjected to fields of airflow-induced oscillatory WSS at different temperature and humidity conditions. Changes in mucin secretion due to WSS were measured and the role of the cytoskeleton in mucin secretion was explored. Mucin secretion significantly increased in response to WSS in a magnitude-dependent manner with respect to static cultures and independently of the airflow temperature and humidity. In static cultures, mucin secretion decreased at high humidity with or without elevation of the temperature with respect to cultures at a comfortable climate. In cultures exposed to WSS, mucin secretion increased at high temperature with respect to cultures at comfortable climate conditions. The polymerization of actin microfilaments was shown to increase mucin secretion under WSS, whereas the dynamics of microtubule polymerization did not affect secretion. In conclusion, the data in this study show that mucin secretion is sensitive to oscillatory WSS as well as high temperature and humidity conditions. PMID:21689518

  13. Regulation of particulate matter-induced mucin secretion by transient receptor potential vanilloid 1 receptors.

    PubMed

    Yu, Hongmei; Li, Qi; Kolosov, Victor P; Perelman, Juliy M; Zhou, Xiangdong

    2012-12-01

    Exposure to airborne particulate matter (PM) is a worldwide health problem. Previous studies have reported that PMs induced depolarizing currents and increased intracellular Ca(2+) in human bronchial epithelial cells. Ca(2+) plays important role in the regulation of mucus exocytosis, and mucin hypersecretion is a key pathological feature of inflammatory respiratory diseases. To explore more mechanisms underlying PM toxicity, we measured PM-induced mucin secretion in human bronchial epithelial (16HBE) cells. MUC5AC secretion and cyclic adenosine monophosphate (cAMP) level were detected by ELISA. Transient receptor potential vanilloid (TRPV)1 inward currents were examined by electrophysiology. Ca(2+) concentration was assessed by laser scanning confocal microscope. Exposure of PMs to 16HBE cells was found to induce mucin secretion, as a consequence of sustained Ca(2+) influx and cAMP increase through TRPV1 receptors. Mucin secretion was completely inhibited by TRPV1 receptor antagonist capsazepine. Removal of Ca(2+) by Ca(2+) chelator BAPTA or inhibition of protein kinase A (PKA) by the PKA inhibitors H-89 each partially reduced PC(2)s-induced mucin secretion. The combination of BAPTA and H-89 completely prevented mucin secretion mediated by PMs. These results suggest that PM induces mucin secretion through Ca(2+) influx and cAMP/PKA pathway by TRPV1 receptors in human bronchial epithelial cells, thereby providing a potential mechanism to reduce PM toxicity. PMID:22829138

  14. Epidermal growth factor system regulates mucin production in airways

    PubMed Central

    Takeyama, Kiyoshi; Dabbagh, Karim; Lee, Heung-Man; Agustí, Carlos; Lausier, James A.; Ueki, Iris F.; Grattan, Kathleen M.; Nadel, Jay A.

    1999-01-01

    Goblet-cell hyperplasia is a critical pathological feature in hypersecretory diseases of airways. However, the underlying mechanisms are unknown, and no effective therapy exists. Here we show that stimulation of epidermal growth factor receptors (EGF-R) by its ligands, EGF and transforming growth factor α (TGFα), causes MUC5AC expression in airway epithelial cells both in in vitro and in vivo. We found that a MUC5AC-inducing epithelial cell line, NCI-H292, expresses EGF-R constitutively; EGF-R gene expression was stimulated further by tumor necrosis factor α (TNFα). EGF-R ligands increased the expression of MUC5AC at both gene and protein levels, and this effect was potentiated by TNFα. Selective EGF-R tyrosine kinase inhibitors blocked MUC5AC expression induced by EGF-R ligands. Pathogen-free rats expressed little EGF-R protein in airway epithelial cells; intratracheal instillation of TNFα induced EGF-R in airway epithelial cells, and subsequent instillation of EGF-R ligands increased the number of goblet cells, Alcian blue–periodic acid–Schiff staining (reflecting mucous glycoconjugates), and MUC5AC gene expression, whereas TNFα, EGF, or TGFα alone was without effect. In sensitized rats, three intratracheal instillations of ovalbumin resulted in EGF-R expression and goblet-cell production in airway epithelium. Pretreatment with EGF-R tyrosine kinase inhibitor, BIBX1522, prevented goblet-cell production both in rats stimulated by TNFα-EGF-R ligands and in an asthma model. These findings suggest potential roles for inhibitors of the EGF-R cascade in hypersecretory diseases of airways. PMID:10077640

  15. Oxidation increases mucin polymer cross-links to stiffen airway mucus gels

    PubMed Central

    Yuan, Shaopeng; Hollinger, Martin; Lachowicz-Scroggins, Marrah E.; Kerr, Sheena C.; Dunican, Eleanor M.; Daniel, Brian M.; Ghosh, Sudakshina; Erzurum, Serpel C.; Willard, Belinda; Hazen, Stanley L.; Huang, Xiaozhu; Carrington, Stephen D.; Oscarson, Stefan; Fahy, John V.

    2015-01-01

    Airway mucus in cystic fibrosis (CF) is highly elastic, but the mechanism behind this pathology is unclear. We hypothesized that the biophysical properties of CF mucus are altered because of neutrophilic oxidative stress. Using confocal imaging, rheology, and biochemical measures of inflammation and oxidation, we found that CF airway mucus gels have a molecular architecture characterized by a core of mucin covered by a web of DNA and a rheological profile characterized by high elasticity that can be normalized by chemical reduction. We also found that high levels of reactive oxygen species in CF mucus correlated positively and significantly with high concentrations of the oxidized products of cysteine (disulfide cross-links). To directly determine whether oxidation can cross-link mucins to increase mucus elasticity, we exposed induced sputum from healthy subjects to oxidizing stimuli and found a marked and thiol-dependent increase in sputum elasticity. Targeting mucin disulfide cross-links using current thiol-amino structures such as N-acetylcysteine (NAC) requires high drug concentrations to have mucolytic effects. We therefore synthesized a thiol-carbohydrate structure (methyl 6-thio-6-deoxy-α-D-galactopyranoside) and found that it had stronger reducing activity than NAC and more potent and fast-acting mucolytic activity in CF sputum. Thus, oxidation arising from airway inflammation or environmental exposure contributes to pathologic mucus gel formation in the lung, which suggests that it can be targeted by thiol-modified carbohydrates. PMID:25717100

  16. Oxidation increases mucin polymer cross-links to stiffen airway mucus gels.

    PubMed

    Yuan, Shaopeng; Hollinger, Martin; Lachowicz-Scroggins, Marrah E; Kerr, Sheena C; Dunican, Eleanor M; Daniel, Brian M; Ghosh, Sudakshina; Erzurum, Serpel C; Willard, Belinda; Hazen, Stanley L; Huang, Xiaozhu; Carrington, Stephen D; Oscarson, Stefan; Fahy, John V

    2015-02-25

    Airway mucus in cystic fibrosis (CF) is highly elastic, but the mechanism behind this pathology is unclear. We hypothesized that the biophysical properties of CF mucus are altered because of neutrophilic oxidative stress. Using confocal imaging, rheology, and biochemical measures of inflammation and oxidation, we found that CF airway mucus gels have a molecular architecture characterized by a core of mucin covered by a web of DNA and a rheological profile characterized by high elasticity that can be normalized by chemical reduction. We also found that high levels of reactive oxygen species in CF mucus correlated positively and significantly with high concentrations of the oxidized products of cysteine (disulfide cross-links). To directly determine whether oxidation can cross-link mucins to increase mucus elasticity, we exposed induced sputum from healthy subjects to oxidizing stimuli and found a marked and thiol-dependent increase in sputum elasticity. Targeting mucin disulfide cross-links using current thiol-amino structures such as N-acetylcysteine (NAC) requires high drug concentrations to have mucolytic effects. We therefore synthesized a thiol-carbohydrate structure (methyl 6-thio-6-deoxy-α-D-galactopyranoside) and found that it had stronger reducing activity than NAC and more potent and fast-acting mucolytic activity in CF sputum. Thus, oxidation arising from airway inflammation or environmental exposure contributes to pathologic mucus gel formation in the lung, which suggests that it can be targeted by thiol-modified carbohydrates. PMID:25717100

  17. Residual oil fly ash induces cytotoxicity and mucin secretion by guinea pig tracheal epithelial cells via an oxidant-mediated mechanism.

    PubMed

    Jiang, N; Dreher, K L; Dye, J A; Li, Y; Richards, J H; Martin, L D; Adler, K B

    2000-03-15

    Inhalation of ambient air particulate matter (PM) is associated with pulmonary injury and inflammation. Using primary cultures of guinea pig tracheal epithelial (GPTE) cells as an in vitro model of airway epithelium, we examined effects of exposure to suspensions of six different emission and ambient air PM samples: residual oil fly ash (ROFA) from an electrical power plant; fly ash from a domestic oil burning furnace (DOFA); ambient air dust from St. Louis (STL), Ottawa (OT), and Washington, DC (WDC); and volcanic ash from the eruption of Mount Saint Helens (MSH) in 1980. Effects of these particulates on cell viability (assessed via LDH assay), secretion of mucin (measured by a monoclonal antibody-based ELISA), and steady-state mRNA levels of the mucin gene MUC2 were determined. ROFA was the most toxic of the dusts tested, as it significantly increased LDH release following a 24-h incubation with 50 microg/cm(2) ROFA. ROFA also enhanced MUC2 mRNA after 4-h exposure, and mucin secretion after 8 h. ROFA-induced mucin secretion and cytotoxicity were attenuated by the oxidant scavenger, dimethylthiourea (DMTU). ROFA exposure also depleted cells of glutathione (GSH). Relatedly, depletion of intracellular GSH by treatment of the cells with buthionine sulfoxamine (BSO) also provoked mucin secretion, as well as enhancing the secretory effect of ROFA when the two agents were added together. L-NMA, the nitric oxide synthase (NOS) inhibitor, did not affect ROFA-induced mucin secretion. Of the soluble transition metals in ROFA (nickel, iron, vanadium), only vanadium individually, or combinations of the metals containing vanadium, provoked secretion. The results suggest ROFA enhances mucin secretion and generates toxicity in vitro to airway epithelium via a mechanism(s) involving generation of oxidant stress, perhaps related to depletion of cellular antioxidant capacity. Deleterious effects of inhalation of ROFA in the respiratory tract in vivo may relate to these cellular

  18. Mucin secretion is modulated by luminal factors in the isolated vascularly perfused rat colon

    PubMed Central

    Barcelo, A; Claustre, J; Moro, F; Chayvialle, J; Cuber, J; Plaisancie, P

    2000-01-01

    BACKGROUND—Mucins play an important protective role in the colonic mucosa. Luminal factors modulating colonic mucus release have been not fully identified.
AIM—To determine the effect of some dietary compounds on mucus discharge in rat colon.
METHODS—An isolated vascularly perfused rat colon model was used. Mucus secretion was induced by a variety of luminal factors administered as a bolus of 1 ml for 30 minutes in the colonic loop. Mucin release was evaluated using a sandwich enzyme linked immunosorbent assay supported by histological analysis.
RESULTS—The three dietary fibres tested in this study (pectin, gum arabic, and cellulose) did not provoke mucus secretion. Luminal administration of sodium alginate (an algal polysaccharide used as a food additive) or ulvan (a sulphated algal polymer) induced a dose dependent increase in mucin discharge over the concentration range 1-25 mg/l (p<0.05 for 25 mg/l alginate and p<0.05 for 10 and 25 mg/l ulvan). Glucuronic acid and galacturonic acid, which are major constituents of a variety of fibres, produced significant mucin secretion (p<0.05). Hydrogen sulphide and mercaptoacetate, two sulphides produced in the colonic lumen by microbial fermentation of sulphated polysaccharides, did not modify mucin secretion. Among the short chain fatty acids, acetate (5-100 mM) induced a dose dependent release of mucus (p<0.05 for 100 mM acetate). Interestingly, butyrate at a concentration of 5 mM produced colonic mucin secretion (p<0.05), but increasing its concentration to 100 mM provoked a gradual decrease in mucus discharge. Propionate (5-100 mM) did not induce mucin release. Several dietary phenolic compounds (quercetin, epicatechin, resveratrol) did not provoke mucus discharge.
CONCLUSIONS—Two algal polysaccharides (alginate and ulvan), two uronic acids (glucuronic acid and galacturonic acid), and the short chain fatty acids acetate and butyrate induce mucin secretion in rat colon. Taken together, these

  19. Regulation of high glucose-mediated mucin expression by matrix metalloproteinase-9 in human airway epithelial cells.

    PubMed

    Yu, Hongmei; Yang, Juan; Xiao, Qian; Lü, Yang; Zhou, Xiangdong; Xia, Li; Nie, Daijing

    2015-04-10

    Mucus hypersecretion is the key manifestation in patients with chronic inflammatory airway diseases and mucin 5AC (MUC5AC) is a major component of airway mucus. Matrix metalloproteinases (MMP)-9, have been found to be involved in the pathogenesis of inflammatory airway diseases. Hyperglycemia has been shown to be an independent risk factor for respiratory infections. We hypothesize that high glucose (HG)-regulates MMP-9 production and MMP-9 activity through nicotinamide adenine dinucleotide phosphate (NADPH)/reactive oxygen species (ROS) cascades pathways, leading to mucin production in human airway epithelial cells (16HBE). We show that HG increases MMP-9 production, MMP-9 activity and MUC5AC expression. These effects are prevented by small interfering RNA (siRNA) for MMP-9, indicating that HG-induced mucin production is MMP-9-dependent. HG activates MMP-9 production, MMP-9 activity and MUC5AC overproduction, which is inhibited by nPG, DMSO and DPI (inhibitors of ROS and NADPH), suggesting that HG-activated mucin synthesis is mediated by NADPH/ROS in 16HBE cells. These observations demonstrate an important role for MMP-9 activated by NADPH/ROS signaling pathways in regulating HG-induced MUC5AC expression. These findings may bring new insights into the molecular pathogenesis of the infections related to diabetes mellitus and lead to novel therapeutic intervention for mucin overproduction in chronic inflammatory airway diseases. PMID:25704757

  20. Secreted mucins in pseudomyxoma peritonei: pathophysiological significance and potential therapeutic prospects

    PubMed Central

    2014-01-01

    Pseudomyxoma peritonei (PMP, ORPHA26790) is a clinical syndrome characterized by progressive dissemination of mucinous tumors and mucinous ascites in the abdomen and pelvis. PMP is a rare disease with an estimated incidence of 1–2 out of a million. Clinically, PMP usually presents with a variety of unspecific signs and symptoms, including abdominal pain and distention, ascites or even bowel obstruction. It is also diagnosed incidentally at surgical or non-surgical investigations of the abdominopelvic viscera. PMP is a neoplastic disease originating from a primary mucinous tumor of the appendix with a distinctive pattern of the peritoneal spread. Computed tomography and histopathology are the most reliable diagnostic modalities. The differential diagnosis of the disease includes secondary peritoneal carcinomatoses and some rare peritoneal conditions. Optimal elimination of mucin and the mucin-secreting tumor comprises the current standard of care for PMP offered in specialized centers as visceral resections and peritonectomy combined with intraperitoneal chemotherapy. This multidisciplinary approach has reportedly provided a median survival rate of 16.3 years, a median progression-free survival rate of 8.2 years and 10- and 15-year survival rates of 63% and 59%, respectively. Despite its indolent, bland nature as a neoplasm, PMP is a debilitating condition that severely impacts quality of life. It tends to be diagnosed at advanced stages and frequently recurs after treatment. Being ignored in research, however, PMP remains a challenging, enigmatic entity. Clinicopathological features of the PMP syndrome and its morbid complications closely correspond with the multifocal distribution of the secreted mucin collections and mucin-secreting implants. Novel strategies are thus required to facilitate macroscopic, as well as microscopic, elimination of mucin and its source as the key components of the disease. In this regard, MUC2, MUC5AC and MUC5B have been found as

  1. Virulent Shigella flexneri Affects Secretion, Expression, and Glycosylation of Gel-Forming Mucins in Mucus-Producing Cells

    PubMed Central

    Sperandio, Brice; Fischer, Natalie; Chevalier-Curt, Marie Joncquel; Rossez, Yannick; Roux, Pascal; Robbe Masselot, Catherine

    2013-01-01

    Mucin glycoproteins are secreted in large amounts by the intestinal epithelium and constitute an efficient component of innate immune defenses to promote homeostasis and protect against enteric pathogens. In this study, our objective was to investigate how the bacterial enteropathogen Shigella flexneri, which causes bacillary dysentery, copes with the mucin defense barrier. We report that upon in vitro infection of mucin-producing polarized human intestinal epithelial cells, virulent S. flexneri manipulates the secretion of gel-forming mucins. This phenomenon, which is triggered only by virulent strains, results in accumulation of mucins at the cell apical surface, leading to the appearance of a gel-like structure that favors access of bacteria to the cell surface and the subsequent invasion process. We identify MUC5AC, a gel-forming mucin, as a component of this structure. Formation of this gel does not depend on modifications of electrolyte concentrations, induction of trefoil factor expression, endoplasmic reticulum stress, or response to unfolded proteins. In addition, transcriptional and biochemical analyses of infected cells reveal modulations of mucin gene expression and modifications of mucin glycosylation patterns, both of which are induced by virulent bacteria in a type III secretion system-dependent manner. Thus, S. flexneri has developed a dedicated strategy to alter the mucus barrier by targeting key elements of the gel-forming capacity of mucins: gene transcription, protein glycosylation, and secretion. PMID:23876800

  2. A formulation for in situ lysis of mucin secreted in pseudomyxoma peritonei.

    PubMed

    Pillai, Krishna; Akhter, Javed; Chua, Terence C; Morris, David L

    2014-01-15

    Although numerous clinical attempts have been made to disintegrate mucin secreted by pseudomyxoma peritonei (PMP), none are clinically recommended. Through examination of the pharmacologic characteristics of two novel agents, we titrated an optimized combination of bromelain and N-acetyl cysteine (NAC) that demonstrates in vitro and in vivo efficacy in the dissolution of mucinous ascites from PMP. In the in vitro experiments, 1 g of mucin was incubated in varying concentrations of bromelain (0-400 µg/ml) and NAC (0-5%) individually followed by a combination before arriving at a therapeutic combination dose of 300 µg/ml bromelain+4% NAC. This established an effective dose of bromelain 300 µg/ml+4% NAC at pH 7.0, when tested in a rat model implanted with 3 g of mucin intraperitoneally (IP). IP administration of the drug in a rat model of PMP was shown to result in mucin disintegration within 72 hr with no toxicity observed. PMID:23843173

  3. Assessment of Intracellular Mucin Content In Vivo

    PubMed Central

    Piccotti, Lucia; Dickey, Burton F.

    2013-01-01

    Airway mucus presents a first line of defense against inhaled materials. It also, however, is a significant pathological contributor to chronic lung diseases such as asthma, cystic fibrosis, and chronic obstructive pulmonary disease. Thus, gaining a better understanding of the mechanisms of mucus production and secretion is an important goal for improving respiratory health. Mucins, the chief glycoprotein components of airway mucus, are very large polymeric glycoproteins, and measuring their production and secretion in experimental animals present significant technical challenges. Over the past several years, we have developed assays for accurately quantifying mucin production and secretion using histological and biochemical assays. These methods are described here. PMID:22259143

  4. Effect of epithelium ATP release on cyclic pressure-induced airway mucus secretion

    PubMed Central

    Tong, Jin; Zhou, Xiang-dong; Perelman, Juliy M.; Kolosov, Victor P.

    2013-01-01

    The cyclic mechanical effect of airflow during breathing creates the optimal airway hydration state. MUC (mucin) 5AC is an important component of the airway mucus. The formation of MUC5AC is related to ATP and intracellular calcium in the epithelial cells. In this study, we evaluated the effect of ATP release from intracellular calcium in epithelial cells on cyclic pressure-induced mucus secretion in the airway. 16HBE (human bronchial epithelial cells) were cultured in vitro on cyclically tilted cultured plates and divided into five groups: control, tilt, tilt and BAPTA–AM (1,2-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid–acetoxymethyl ester), tilt and EGTA and tilt and RB-2 (reactive blue-2). The shear stress and compressive stress were induced by the surface tension of the liquid, atmospheric pressure and liquid gravity. Cell activity, MUC5AC mRNA expression level, MUC5AC protein expression level and ATP release and intracellular calcium changes were measured with the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay, RT–PCR (reverse transcription–PCR), HPLC and inverted fluorescence microscope, respectively. We detected that cyclic pressure significantly increased MUC5AC secretion and ATP release. The enhanced ATP release could be inhibited by both BAPTA–AM and RB-2, while EGTA did not have a suppressive effect. BAPTA–AM, EGTA and RB-2 did not obviously inhibit MUC5AC mRNA expression. Cyclic pressure did not induce MUC5AC secretion in the airway mucus epithelium via Ca2+-dependent ATP release, and nearly all Ca2+ was provided by stored intracellular Ca2+. PMID:24329423

  5. Effect of epithelium ATP release on cyclic pressure-induced airway mucus secretion.

    PubMed

    Tong, Jin; Zhou, Xiang-Dong; Perelman, Juliy M; Kolosov, Victor P

    2013-12-16

    The cyclic mechanical effect of airflow during breathing creates the optimal airway hydration state. Mucin (MUC) 5AC is an impotent component of the airway mucus. The formation of MUC5AC is related to adenosine triphosphate (ATP) and intracellular calciumin the epithelial cells. In this study, we evaluated the effect of ATP release from and intracellular calcium in epithelial cells on cyclic pressure-induced mucus secretion in the airway. Human bronchial epithelial cells (16HBE) were cultured in vitro on cyclically tilted cultured plates and divided into 5 groups: control, tilt, tilt and BAPTA-AM, tilt and EGTA, and tilt and RB-2. The shear stress and compressive stress were induced by the surface tension of the liquid, atmospheric pressure and liquid gravity. Cell activity, MUC5AC mRNA expression level, MUC5AC protein expression level and ATP release, and intracellular calcium changes were measured with the MTT assay, RT-PCR, high performance liquid chromatography (HPLC) and inverted fluorescence microscope, respectively. We detected that cyclic pressure significantly increased MUC5AC secretion and ATP release. The enhanced ATP release could be inhibited by both BAPTA-AM and RB-2, while EGTA did not have a suppressive effect. BAPTA-AM, EGTA, and RB-2 did not obviously inhibit MUC5AC mRNA expression.Cyclic pressure did not induce MUC5AC secretion in the airway mucus epithelium via Ca2+-dependent ATP release, and nearly all Ca2+ was provided by stored intracellular Ca2+. PMID:24329423

  6. The polymeric mucin Muc5ac is required for allergic airway hyperreactivity

    PubMed Central

    Evans, Christopher M.; Raclawska, Dorota S.; Ttofali, Fani; Liptzin, Deborah R.; Fletcher, Ashley A.; Harper, Daniel N.; McGing, Maggie A.; McElwee, Melissa M.; Williams, Olatunji W.; Sanchez, Elizabeth; Roy, Michelle G.; Kindrachuk, Kristen N.; Wynn, Thomas A.; Eltzschig, Holger K.; Blackburn, Michael R.; Tuvim, Michael J.; Janssen, William J.; Schwartz, David A.; Dickey, Burton F.

    2015-01-01

    In asthma, airflow obstruction is thought to result primarily from inflammation-triggered airway smooth muscle (ASM) contraction. However, anti-inflammatory and smooth muscle-relaxing treatments are often temporary or ineffective. Overproduction of the mucin MUC5AC is an additional disease feature that, while strongly associated pathologically, is poorly understood functionally. Here we show that Muc5ac is a central effector of allergic inflammation that is required for airway hyperreactivity (AHR) to methacholine (MCh). In mice bred on two well-characterized strain backgrounds (C57BL/6 and BALB/c) and exposed to two separate allergic stimuli (ovalbumin and Aspergillus extract), genetic removal of Muc5ac abolishes AHR. Residual MCh responses are identical to unchallenged controls, and although inflammation remains intact, heterogeneous mucus occlusion decreases by 74%. Thus, whereas inflammatory effects on ASM alone are insufficient for AHR, Muc5ac-mediated plugging is an essential mechanism. Inhibiting MUC5AC may be effective for treating asthma and other lung diseases where it is also overproduced. PMID:25687754

  7. Surface fluid absorption and secretion in small airways

    PubMed Central

    Shamsuddin, A K M; Quinton, P M

    2012-01-01

    Native small airways must remain wet enough to be pliable and support ciliary clearance, but dry enough to remain patent for gas flow. The airway epithelial lining must both absorb and secrete ions to maintain a critical level of fluid on its surface. Despite frequent involvement in lung diseases, the minuscule size has limited studies of peripheral airways. To meet this challenge, we used a capillary to construct an Ussing chamber (area <1 mm2) to measure electrolyte transport across small native airways (∼1 mm ø) from pig lung. Transepithelial potentials (Vt) were recorded in open circuit conditions while applying constant current pulses across the luminal surface of dissected airways to calculate transepithelial electrical conductance (Gt) and equivalent short circuit current () in the presence and absence of selected Na+ and Cl− transport inhibitors (amiloride, GlyH-101, Niflumic acid) and agonists (Forskolin + IBMX, UTP). Considered together the responses suggest an organ composed of both secreting and absorbing epithelia that constitutively and concurrently transport fluids into and out of the airway, i.e. in opposite directions. Since the epithelial lining of small airways is arranged in long, accordion-like rows of pleats and folds that run axially down the lumen, we surmise that cells within the pleats are mainly secretory while the cells of the folds are principally absorptive. This structural arrangement could provide local fluid transport from within the pleats toward the luminal folds that may autonomously regulate the local surface fluid volume for homeostasis while permitting acute responses to maintain clearance. PMID:22547637

  8. Effects of Lupenone, Lupeol, and Taraxerol Derived from Adenophora triphylla on the Gene Expression and Production of Airway MUC5AC Mucin

    PubMed Central

    Yoon, Yong Pill; Lee, Hyun Jae; Lee, Dong-Ung; Lee, Sang Kook; Hong, Jang-Hee

    2015-01-01

    Background Adenophora triphylla var. japonica is empirically used for controlling airway inflammatory diseases in folk medicine. We evaluated the gene expression and production of mucin from airway epithelial cells in response to lupenone, lupeol and taraxerol derived from Adenophora triphylla var. japonica. Methods Confluent NCI-H292 cells were pretreated with lupenone, lupeol or taraxerol for 30 minutes and then stimulated with tumor necrosis factor α (TNF-α) for 24 hours. The MUC5AC mucin gene expression and production were measured by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. Additionally, we examined whether lupenone, lupeol or taraxerol affects MUC5AC mucin production induced by epidermal growth factor (EGF) and phorbol 12-myristate 13-acetate (PMA), the other 2 stimulators of airway mucin production. Results Lupenone, lupeol, and taraxerol inhibited the gene expression and production of MUC5AC mucin induced by TNF-α from NCI-H292 cells, respectively. The 3 compounds inhibited the EGF or PMA-induced production of MUC5AC mucin in NCI-H292 cells. Conclusion These results indicated that lupenone, lupeol and taraxerol derived from Adenophora triphylla var. japonica regulates the production and gene expression of mucin, by directly acting on airway epithelial cells. In addition, the results partly explain the mechanism of of Adenophora triphylla var. japonica as a traditional remedy for diverse inflammatory pulmonary diseases. PMID:26175774

  9. Bacteria may induce the secretion of mucin-like proteins by the diatom Phaeodactylum tricornutum.

    PubMed

    Buhmann, Matthias T; Schulze, Birgit; Förderer, Alexander; Schleheck, David; Kroth, Peter G

    2016-06-01

    Benthic diatoms live in photoautotrophic/heterotrophic biofilm communities embedded in a matrix of secreted extracellular polymeric substances. Closely associated bacteria influence their growth, aggregation, and secretion of exopolymers. We have studied a diatom/bacteria model community, in which a marine Roseobacter strain is able to grow with secreted diatom exopolymers as a sole source of carbon. The strain influences the aggregation of Phaeodactylum tricornutum by inducing a morphotypic transition from planktonic, fusiform cells to benthic, oval cells. Analysis of the extracellular soluble proteome of P. tricornutum in the presence and absence of bacteria revealed constitutively expressed newly identified proteins with mucin-like domains that appear to be typical for extracellular diatom proteins. In contrast to mucins, the proline-, serine-, threonine-rich (PST) domains in these proteins were also found in combination with protease-, glucosidase- and leucine-rich repeat-domains. Bioinformatic functional predictions indicate that several of these newly identified diatom-specific proteins may be involved in algal defense, intercellular signaling, and aggregation. PMID:26993172

  10. A family of secreted mucins from the parasitic nematode Toxocara canis bears diverse mucin domains but shares similar flanking six-cysteine repeat motifs.

    PubMed

    Loukas, A; Hintz, M; Linder, D; Mullin, N P; Parkinson, J; Tetteh, K K; Maizels, R M

    2000-12-15

    Infective larvae of the parasitic nematode Toxocara canis secrete a family of mucin-like glycoproteins, which are implicated in parasite immune evasion. Analysis of T. canis expressed sequence tags identified a family of four mRNAs encoding distinct apomucins (Tc-muc-1-4), one of which had been previously identified in the TES-120 family of glycoproteins secreted by this parasite. The protein products of all four cDNAs contain signal peptides, a repetitive serine/threonine-rich tract, and varying numbers of 36-amino acid six-cysteine (SXC) domains. SXC domains are found in many nematode proteins and show similarity to cnidarian (sea anemone) toxins. Antibodies to the SXC domains of Tc-MUC-1 and Tc-MUC-3 recognize differently migrating members of TES-120. TES-120 proteins separated by chromatographic methods showed distinct amino acid composition, mass, and sequence information by both Edman degradation and matrix-assisted laser desorption ionization/time of flight mass spectrometry on peptide fragments. Tc-MUC-1, -2, and -3 were shown to be secreted mucins with real masses of 39.7, 47.8, and 45.0 kDa in contrast to their predicted peptide masses of 15.7, 16.2, and 26.0 kDa, respectively. The presence of SXC domains in all mucin products supports the suggestion that the SXC motif is required for mucin assembly or export. Homology modeling indicates that the six-cysteine domains of the T. canis mucins adopt a similar fold to the sea anemone potassium channel-blocking toxin BgK, forming three disulfide bonds within each subunit. PMID:10950959

  11. Actions of adenosine A1 and A2 receptor antagonists on CFTR antibody-inhibited β-adrenergic mucin secretion response

    PubMed Central

    Pereira, M M C; Lloyd Mills, C; Dormer, R L; McPherson, M A

    1998-01-01

    The cystic fibrosis gene protein, the cystic fibrosis transmembrane conductance regulator (CFTR) acts as a chloride channel and is a key regulator of mucin secretion. The mechanism by which 3-isobutyl-1-methylxanthine (IBMX) corrects the defect in CFTR mediated β-adrenergic stimulation of mucin secretion has not been determined. The present study has investigated the actions of adenosine A1 and A2 receptor antagonists to determine whether ability to stimulate mucin secretion correlates with correction of CFTR antibody inhibited β-adrenergic response and whether excessive cyclic AMP rise is required.CFTR antibodies were introduced into living rat submandibular acini by hypotonic swelling. Following recovery, mucin secretion in response to isoproterenol was measured.The adenosine A1 receptor antagonist, 8 cyclopentyltheophylline (CPT) was a less potent stimulator of mucin secretion than was the A2 receptor antagonist dimethylpropargylxanthine (DMPX). A concentration of CPT close to the Ki for A1 receptor antagonism (10 nM) did not stimulate mucin secretion.DMPX, although a potent stimulator of mucin secretion, did not correct CFTR antibody inhibited mucin secretion.CPT corrected defective CFTR antibody inhibited mucin secretion at a high (1 mM) concentration, suggesting a mechanism other than adenosine receptor antagonism.DMPX potentiated the isoproterenol induced cyclic AMP rise, whereas CPT did not.Correction of the defective CFTR mucin secretion response did not correlate with ability to stimulate mucin secretion and did not require potentiation of β-adrenergic induced increases in cyclic AMP. This affords real promise for the development of a selective drug treatment for cystic fibrosis. PMID:9831904

  12. Increased Th2 cytokine secretion, eosinophilic airway inflammation, and airway hyperresponsiveness in neurturin-deficient mice.

    PubMed

    Michel, Tatiana; Thérésine, Maud; Poli, Aurélie; Domingues, Olivia; Ammerlaan, Wim; Brons, Nicolaas H C; Hentges, François; Zimmer, Jacques

    2011-06-01

    Neurotrophins such as nerve growth factor and brain-derived neurotrophic factor have been described to be involved in the pathogenesis of asthma. Neurturin (NTN), another neurotrophin from the glial cell line-derived neurotrophic factor family, was shown to be produced by human immune cells: monocytes, B cells, and T cells. Furthermore, it was previously described that the secretion of inflammatory cytokines was dramatically stimulated in NTN knockout (NTN(-/-)) mice. NTN is structurally similar to TGF-β, a protective cytokine in airway inflammation. This study investigates the implication of NTN in a model of allergic airway inflammation using NTN(-/-) mice. The bronchial inflammatory response of OVA-sensitized NTN(-/-) mice was compared with wild-type mice. Airway inflammation, Th2 cytokines, and airway hyperresponsiveness (AHR) were examined. NTN(-/-) mice showed an increase of OVA-specific serum IgE and a pronounced worsening of inflammatory features. Eosinophil number and IL-4 and IL-5 concentration in the bronchoalveolar lavage fluid and lung tissue were increased. In parallel, Th2 cytokine secretion of lung draining lymph node cells was also augmented when stimulated by OVA in vitro. Furthermore, AHR was markedly enhanced in NTN(-/-) mice after sensitization and challenge when compared with wild-type mice. Administration of NTN before challenge with OVA partially rescues the phenotype of NTN(-/-) mice. These findings provide evidence for a dampening role of NTN on allergic inflammation and AHR in a murine model of asthma. PMID:21508262

  13. Bile Salts Modulate the Mucin-Activated Type VI Secretion System of Pandemic Vibrio cholerae

    PubMed Central

    Unterweger, Daniel; Diaz-Satizabal, Laura; Ogg, Stephen; Pukatzki, Stefan

    2015-01-01

    The causative agent of cholera, Vibrio cholerae, regulates its diverse virulence factors to thrive in the human small intestine and environmental reservoirs. Among this pathogen’s arsenal of virulence factors is the tightly regulated type VI secretion system (T6SS). This system acts as an inverted bacteriophage to inject toxins into competing bacteria and eukaryotic phagocytes. V. cholerae strains responsible for the current 7th pandemic activate their T6SS within the host. We established that T6SS-mediated competition occurs upon T6SS activation in the infant mouse, and that this system is functional under anaerobic conditions. When investigating the intestinal host factors mucins (a glycoprotein component of mucus) and bile for potential regulatory roles in controlling the T6SS, we discovered that once mucins activate the T6SS, bile acids can further modulate T6SS activity. Microbiota modify bile acids to inhibit T6SS-mediated killing of commensal bacteria. This interplay is a novel interaction between commensal bacteria, host factors, and the V. cholerae T6SS, showing an active host role in infection. PMID:26317760

  14. Butyrate modulates bacterial adherence on LS174T human colorectal cells by stimulating mucin secretion and MAPK signaling pathway

    PubMed Central

    Jung, Tae-Hwan; Park, Jeong Hyeon; Han, Kyoung-Sik

    2015-01-01

    BACKGROUND/OBJECTIVES Fermentation of dietary fiber results in production of various short chain fatty acids in the colon. In particular, butyrate is reported to regulate the physical and functional integrity of the normal colonic mucosa by altering mucin gene expression or the number of goblet cells. The objective of this study was to investigate whether butyrate modulates mucin secretion in LS174T human colorectal cells, thereby influencing the adhesion of probiotics such as Lactobacillus and Bifidobacterium strains and subsequently inhibiting pathogenic bacteria such as E. coli. In addition, possible signaling pathways involved in mucin gene regulation induced by butyrate treatment were also investigated. MATERIALS/METHODS Mucin protein content assay and periodic acid-Schiff (PAS) staining were performed in LS174T cells treated with butyrate at various concentrations. Effects of butyrate on the ability of probiotics to adhere to LS174T cells and their competition with E. coli strains were examined. Real time polymerase chain reaction for mucin gene expression and Taqman array 96-well fast plate-based pathway analysis were performed on butyrate-treated LS174T cells. RESULTS Treatment with butyrate resulted in a dose-dependent increase in mucin protein contents in LS174T cells with peak effects at 6 or 9 mM, which was further confirmed by PAS staining. Increase in mucin protein contents resulted in elevated adherence of probiotics, which subsequently reduced the adherent ability of E. coli. Treatment with butyrate also increased transcriptional levels of MUC3, MUC4, and MUC12, which was accompanied by higher gene expressions of signaling kinases and transcription factors involved in mitogen-activated protein kinase (MAPK) signaling pathways. CONCLUSIONS Based on our results, butyrate is an effective regulator of modulation of mucin protein production at the transcriptional and translational levels, resulting in changes in the adherence of gut microflora. Butyrate

  15. Enterotoxigenic Escherichia coli secretes a highly conserved mucin-degrading metalloprotease to effectively engage intestinal epithelial cells.

    PubMed

    Luo, Qingwei; Kumar, Pardeep; Vickers, Tim J; Sheikh, Alaullah; Lewis, Warren G; Rasko, David A; Sistrunk, Jeticia; Fleckenstein, James M

    2014-02-01

    Enterotoxigenic Escherichia coli (ETEC) is a leading cause of death due to diarrheal illness among young children in developing countries, and there is currently no effective vaccine. Many elements of ETEC pathogenesis are still poorly defined. Here we demonstrate that YghJ, a secreted ETEC antigen identified in immunoproteomic studies using convalescent patient sera, is required for efficient access to small intestinal enterocytes and for the optimal delivery of heat-labile toxin (LT). Furthermore, YghJ is a highly conserved metalloprotease that influences intestinal colonization of ETEC by degrading the major mucins in the small intestine, MUC2 and MUC3. Genes encoding YghJ and its cognate type II secretion system (T2SS), which also secretes LT, are highly conserved in ETEC and exist in other enteric pathogens, including other diarrheagenic E. coli and Vibrio cholerae bacteria, suggesting that this mucin-degrading enzyme may represent a shared virulence feature of these important pathogens. PMID:24478067

  16. Enterotoxigenic Escherichia coli Secretes a Highly Conserved Mucin-Degrading Metalloprotease To Effectively Engage Intestinal Epithelial Cells

    PubMed Central

    Luo, Qingwei; Kumar, Pardeep; Vickers, Tim J.; Sheikh, Alaullah; Lewis, Warren G.; Rasko, David A.; Sistrunk, Jeticia

    2014-01-01

    Enterotoxigenic Escherichia coli (ETEC) is a leading cause of death due to diarrheal illness among young children in developing countries, and there is currently no effective vaccine. Many elements of ETEC pathogenesis are still poorly defined. Here we demonstrate that YghJ, a secreted ETEC antigen identified in immunoproteomic studies using convalescent patient sera, is required for efficient access to small intestinal enterocytes and for the optimal delivery of heat-labile toxin (LT). Furthermore, YghJ is a highly conserved metalloprotease that influences intestinal colonization of ETEC by degrading the major mucins in the small intestine, MUC2 and MUC3. Genes encoding YghJ and its cognate type II secretion system (T2SS), which also secretes LT, are highly conserved in ETEC and exist in other enteric pathogens, including other diarrheagenic E. coli and Vibrio cholerae bacteria, suggesting that this mucin-degrading enzyme may represent a shared virulence feature of these important pathogens. PMID:24478067

  17. Importance of acidic mucin secretions by foveolar and mucous neck cells of rat fundic mucosa as the defence mechanisms against HCl as revealed by fasting.

    PubMed

    Yamazaki, Y; Ueda, T; Kohli, Y; Fujiki, N; Imamura, Y; Fukuda, M

    1992-01-01

    The localization of neutral mucin and acidic mucins in both control and fasted rat gastric fundic mucosa were examined by microscopic and electron microscopic histochemical methods. By Carnoy's fixation, the surface mucous coat of the control rat gastric fundic mucosa was found to be composed of alternating layers of acidic mucins and neutral mucin, indicating the synchronous and cyclic secretions of them. In many gastric pits of the fundic glands, the acidic mucins were found to spring out from the deep foveolar regions like volcanoes. This phenomenon may suggest that the acidic mucins play a fundamental role in protecting the pit cells against HCl during its passage, and the layers of neutral mucin and acidic mucins in the surface coat is the safeguard against the HCl and digestive enzymes in the gastric lumen. In the fasting rat gastric fundic mucosa, the acidity and the amount of the gastric juice were markedly decreased, indicating the suppressed secretions of mucins and HCl. The decreased production of sulfomucin was directly demonstrated by 35SO4-autoradiography. Many mucous neck cells existing in close association with the parietal cells were ballooned due to accumulation of alcian blue (AB)-positive but high iron-diamine (HID)-negative sialomucin, which was not demonstrable in the control. The secretory granules of sialomucin contained in the ballooned mucous neck cells were positively stained ultrastructurally with cacodylate-ferric colloid to stain acid mucopolysaccharides. PMID:1380850

  18. Lysozyme secretion by submucosal glands protects the airway from bacterial infection.

    PubMed

    Dajani, Rana; Zhang, Yulong; Taft, Peter J; Travis, Sue M; Starner, Timothy D; Olsen, Ansgar; Zabner, Joseph; Welsh, Michael J; Engelhardt, John F

    2005-06-01

    Submucosal glands are abundant (approximately 1 gland/mm2) secretory structures in the tracheobronchial airways of the human lung. Because submucosal glands express antibacterial proteins, it has been proposed that they contribute to lung defense. However, this concept is challenged by the fact that mice do not have submucosal glands in their bronchial airways, yet are quite resistant to bacterial lung infection. The contribution of airway submucosal glands to host defense is also debated as a pathophysiologic component of cystic fibrosis lung disease. Here, we asked whether submucosal glands protect airways against bacterial infection. By comparing tracheal xenograft airways with and without glands, we found that the presence of glands enhanced bacterial killing in vivo and by airway secretions in vitro. Moreover, immunodepletion studies suggested that lysozyme is a major antibacterial component secreted by submucosal glands. These studies provide evidence that submucosal glands are a major source of antibacterials critical for maintaining sterile airways. PMID:15746432

  19. Lysozyme Secretion by Submucosal Glands Protects the Airway from Bacterial Infection

    PubMed Central

    Dajani, Rana; Zhang, Yulong; Taft, Peter J.; Travis, Sue M.; Starner, Timothy D.; Olsen, Ansgar; Zabner, Joseph; Welsh, Michael J.; Engelhardt, John F.

    2005-01-01

    Submucosal glands are abundant (∼ 1 gland/mm2) secretory structures in the tracheobronchial airways of the human lung. Because submucosal glands express antibacterial proteins, it has been proposed that they contribute to lung defense. However, this concept is challenged by the fact that mice do not have submucosal glands in their bronchial airways, yet are quite resistant to bacterial lung infection. The contribution of airway submucosal glands to host defense is also debated as a pathophysiologic component of cystic fibrosis lung disease. Here, we asked whether submucosal glands protect airways against bacterial infection. By comparing tracheal xenograft airways with and without glands, we found that the presence of glands enhanced bacterial killing in vivo and by airway secretions in vitro. Moreover, immunodepletion studies suggested that lysozyme is a major antibacterial component secreted by submucosal glands. These studies provide evidence that submucosal glands are a major source of antibacterials critical for maintaining sterile airways. PMID:15746432

  20. A soluble secreted glycoprotein (eCLCA1) is overexpressed due to goblet cell hyperplasia and metaplasia in horses with recurrent airway obstruction.

    PubMed

    Range, F; Mundhenk, L; Gruber, A D

    2007-11-01

    The equine putative chloride channel protein eCLCA1 is thought to be critically involved in the pathogenesis of recurrent airway obstruction (RAO) via modulation of the hydration of airway mucins. A recent study revealed a strong increase of eCLCA1 messenger ribonucleic acid (mRNA) in the lungs of horses with RAO. In this study, eCLCA1 protein and mRNA expression were quantified in airway goblet cells of 9 horses affected with RAO and 9 control horses by using immunohistochemistry and laser microdissection followed by real-time quantitative reverse transcription polymerase chain reaction, respectively. Horses affected by RAO had strong goblet cell metaplasia in bronchioles and goblet cell hyperplasia in bronchi and the trachea. Expression of the eCLCA1 protein was tightly linked to all airway goblet cells in both groups. No differences were detected in the ratio of eCLCA1 mRNA copy numbers to the mRNA copy numbers of the housekeeping gene EF-1a per goblet cell between horses affected with RAO and unaffected horses, suggesting that the increase in eCLCA1 expression is because of increased numbers of goblet cells and not transcriptional upregulation of the eCLCA1 gene. In addition, biochemical analyses of the eCLCA1 protein after in vitro translation and heterologous expression in cultured cells revealed that eCLCA1 is a secreted glycoprotein and not an integral membrane protein. Taken together, the results suggest that eCLCA1 mediates its effect as a soluble constituent of airway mucins that is overexpressed in RAO airways because of goblet cell hyperplasia and metaplasia, not transcriptional upregulation. PMID:18039903

  1. Induction of cyclooxygenase-2 in monocyte/macrophage by mucins secreted from colon cancer cells

    PubMed Central

    Inaba, Takaaki; Sano, Hajime; Kawahito, Yutaka; Hla, Timothy; Akita, Kaoru; Toda, Munetoyo; Yamashina, Ikuo; Inoue, Mizue; Nakada, Hiroshi

    2003-01-01

    Up-regulation of cyclooxygenase-2 (COX-2) and overproduction of prostaglandins have been implicated in the initiation and/or progression of colon cancer. However, it is uncertain in which cells and how COX-2 is induced initially in the tumor microenvironment. We found that a conditioned medium of the colon cancer cell line, LS 180, contained a factor to induce COX-2 in human peripheral blood mononuclear cells. This factor was purified biochemically and revealed to be mucins. A small amount of mucins (≈100 ng of protein per ml) could elevate prostaglandin E2 production by monocytes. The mucins induced COX-2 mRNA and protein levels of monocytes in a dose- and time-dependent manner, indicating a COX-2-mediated pathway. We also have examined immunohistochemically the localization of COX-2 protein and mucins in human colorectal cancer tissues. It is noteworthy that COX-2-expressing macrophages were located around the region in which mucins were detectable, suggesting that COX-2 also was induced by mucins in vivo. These results suggest that mucins produced by colon cancer cells play a critical role in the initial induction of COX-2 in the tumor microenvironment. PMID:12598658

  2. "Mucin"-secreting papillary renal cell carcinoma: clinicopathological, immunohistochemical, and molecular genetic analysis of seven cases.

    PubMed

    Pivovarcikova, Kristyna; Peckova, Kvetoslava; Martinek, Petr; Montiel, Delia Perez; Kalusova, Kristyna; Pitra, Tomas; Hora, Milan; Skenderi, Faruk; Ulamec, Monika; Daum, Ondrej; Rotterova, Pavla; Ondic, Ondrej; Dubova, Magdalena; Curik, Romuald; Dunatov, Ana; Svoboda, Tomas; Michal, Michal; Hes, Ondrej

    2016-07-01

    Mucin and mucin-like material are features of mucinous tubular and spindle renal cell carcinoma (MTS RCC) but are rarely seen in papillary renal cell carcinoma (PRCC). We reviewed 1311 PRCC and identified 7 tumors containing extracellular and/or intracellular mucinous/mucin-like material (labeled as PRCCM). We analyzed these using morphological, histochemical, immunohistochemical, and molecular genetic methods (arrayCGH, FISH). Clinical data were available for six of the seven patients (five males and one female, age range 61-78 years). Follow-up was available for four patients (2-4 years); one patient died of widespread metastases. Tumor size ranged from 3 to 5 cm (mean 3.8). Of all cases, histological architecture showed a predominantly papillary pattern. Mucin or mucin-like was extracellular in one, intracellular in three, and both intra/extracellular in three cases. All tumors were positive for AMACR, vimentin, and OSCAR, while CK7 was positive in four. Mucicarmine stain was positive in all cases, PAS in six and Alcian blue in three cases. Five tumors were positive for MUC 1, but none were positive for MUC 2, MUC 4, or MUC 6. In only four cases, genetic analysis could be performed. Gain of chromosomes 7 and 17 was found in two cases; gain of 17 only was found in one case. Loss of heterozygosity of 3p was found in one case together with polysomy of chromosomes 7 and 17. No abnormalities of VHL, fumarate dehydrogenase, and TFE3 genes were detected. We conclude that PRCCM is a rare but challenging subtype of RCC that deserves to be further studied. In all the tumors, the mucin-like material was found in those stained with mucicarmin, but other conventional and immunohistochemical stains did not reveal consistent features of a single mucin. The molecular-genetic profile of these tumors was most consistent with that of typical papillary RCC, although one case had mixed genetic features of papillary and clear RCC. PRCCM has metastatic potential, as evidenced by

  3. Mucin secretion in germfree rats fed fiber-free and psyllium diets and bacterial mass and carbohydrate fermentation after colonization.

    PubMed

    Cabotaje, L M; Shinnick, F L; Lopéz-Guisa, J M; Marlett, J A

    1994-04-01

    The effect of psyllium on mucin secretion was determined by comparing water-soluble and -insoluble fractions of excreta from germfree rats fed a fiber-free (FF) diet or a diet containing psyllium seed husk (PS). Excreta from the same rats after colonization with a rat mixed cecal culture were separated into water-soluble, plant, and bacterial fractions to compare the remaining carbohydrate and the mass of bacteria. The sugar composition and water solubility of carbohydrate in excreta from germfree rats fed FF diets indicated that a primary fermentable substrate was mucin. PS increased fecal excretion of mucin-derived sugars almost threefold in germfree rats. Fecal carbohydrate was reduced from 619 to 237 mumol/g of dry feces and mostly in the bacterial fraction when rats fed an FF diet were colonized. The total sugar content and the amount of muramic acid, but not bacterial counts and mass, indicated that PS increased fecal bacteria. Fractionation of excreta from PS-fed rats was complicated by a gel which, based on sugar composition, was PS. Sugar composition of the water-soluble fraction from excreta from PS-fed rats suggested that it contained some bacterial component, possibly exopolysaccharides and some of the PS, but not mucin. PS digestibility ranged from 60 to 80%, depending on what fecal fraction was used for output. Because of the presence of PS-derived sugars in the gel and soluble fraction, it was not possible to determine which, if any, of the PS digestibilities was correct. PMID:8017918

  4. Mucin-Related Molecular Responses of Bronchial Epithelial Cells in Rats Infected with the Nematode Nippostrongylus brasiliensis

    PubMed Central

    Soga, Koichi; Yamada, Minoru; Naito, Yuji; Yoshikawa, Toshikazu; Arizono, Naoki

    2013-01-01

    Although mucins are essential for the protection of internal epithelial surfaces, molecular responses involving mucin production and secretion in response to various infectious agents in the airway have not been fully elucidated. The present study analysed airway goblet cell mucins in rats infected with the nematode Nippostrongylus brasiliensis, which migrates to the lungs shortly after infection. Goblet cell hyperplasia occurred in the bronchial epithelium 3–10 days after infection. The high iron diamine-alcian blue staining combined with neuraminidase treatment showed that sialomucin is the major mucin in hyperplastic goblet cells. Immunohistochemical studies demonstrated that goblet cell mucins were immunoreactive with both the major airway mucin core peptide, Muc5AC, and the major intestinal mucin core peptide Muc2. Reverse transcription real-time PCR studies demonstrated upregulation of gene transcription levels of Muc5AC, Muc2, the sialyltransferase St3gal4, and the resistin-like molecule beta (Retnlb) in the lungs. These results showed that nematode infection induces airway epithelial responses characterised by the production of sialomucin with Muc5AC and Muc2 core peptides. These mucins, as well as Retnlb, might have important roles in the protection of mucosa from migrating nematodes in the airway. PMID:27335862

  5. Rhythmic Pressure Waves Induce Mucin5AC Expression via an EGFR-Mediated Signaling Pathway in Human Airway Epithelial Cells

    PubMed Central

    Liu, Chunyi; Li, Qi; Kolosov, Victor P.; Perelman, Juliy M.

    2013-01-01

    Rhythmic pressure waves (RPW), mimicking the mechanical forces generated during normal breathing, play a key role in airway surface liquid (ASL) homeostasis. As a major component of ASL, we speculated that the mucin5AC (MUC5AC) expression must also be regulated by RPW. However, fewer researches have focused on this question. Therefore, our aim was to test the effect and mechanism of RPW on MUC5AC expression in cultured human bronchial epithelial cells. Compared with the relevant controls, the transcriptional level of MUC5AC and the protein expressions of MUC5AC, the phospho-epidermal growth factor receptor (p-EGFR), phospho-extracellular signal-related kinase (p-ERK), and phospho-Akt (p-Akt) were all significantly increased after mechanical stimulation. However, this effect could be significantly attenuated by transfecting with EGFR-siRNA. Similarly, pretreating with the inhibitor of ERK or phosphatidylinositol 3-kinases (PI3K)/Akt separately or jointly also significantly reduced MUC5AC expression. Collectively, these results indicate that RPW modulate MUC5AC expression via the EGFR-PI3K-Akt/ERK-signaling pathway in human bronchial epithelial cells. PMID:23768102

  6. Cold-inducible RNA binding protein regulates mucin expression induced by cold temperatures in human airway epithelial cells.

    PubMed

    Ran, DanHua; Chen, LingXiu; Xie, WenYue; Xu, Qing; Han, Zhong; Huang, HuaPing; Zhou, XiangDong

    2016-08-01

    Mucus overproduction is an important manifestation of chronic airway inflammatory diseases, however, the mechanisms underlying the association between cold air and mucus overproduction remain unknown. We found that the expression of the cold-inducible RNA binding protein (CIRP) was increased in patients with chronic obstructive pulmonary disease (COPD). In the present study, we tested whether CIRP was involved in inflammatory factors and mucin5AC (MUC5AC) expression after cold stimulation and investigated the potential signaling pathways involved in this process. We found that CIRP was highly expressed in the bronchi of COPD patients. The expression of CIRP, interleukin-1β (IL-1β) and tumor necrosis factor α (TNF-α) were increased, and the CIRP was localized in cytoplasm after cold stimulation. MUC5AC mRNA and protein expression levels were elevated in a temperature- and time-dependent manner after cold stimulation and were associated with the phosphorylation of ERK and NF-κB, which reflected their activation. These responses were suppressed by knockdown of CIRP with a specific siRNA or the ERK and NF-κB inhibitors. These results demonstrated that CIRP was expressed in the bronchi of human COPD patients and was involved in inflammatory factors and MUC5AC expression after cold stimulation through the ERK and NF-κB pathways. PMID:27184164

  7. [An almost fatal airway obstruction caused by a secretion plug in an endotracheal tube].

    PubMed

    Andersen, Emir Benjamin; Olsen, Karsten Skovgaard

    2014-12-15

    Airway obstruction caused by a secretion plug in an endotracheal tube or a tracheostomy cannula can be a serious complication to mechanical ventilation. This case describes an event caused by a mucus plug localized to the distal part of a tracheostomy tube in a tetraplegic patient. The plug functioned as a check valve, allowing air to pass in - but not out - of the patient. A suction catheter could be passed through the airway without any resistance, and thus the airway was believed to be free. The event, which had an almost fatal outcome due to hyperinflation of the lungs, was relieved by replacement of the tracheostomy cannula. PMID:25497629

  8. Effects of second hand smoke on airway secretion and mucociliary clearance

    PubMed Central

    Liu, Yanyan; Di, Y. Peter

    2012-01-01

    The airway acts as the first defense against inhaled pathogens and particulate matter from the environment. One major way for the airway to clear inhaled foreign objects is through mucociliary clearance (MCC), an important component of the respiratory innate immune defense against lung disease. MCC is characterized by the upward movement of mucus by ciliary motion that requires a balance between the volume and composition of the mucus, adequate periciliary liquid (PCL) volume, and normal ciliary beat frequency (CBF). Airway surface fluid (ASL) is a thin layer liquid that consists of the highly viscous mucus upper “gel” layer, and the watery lubricating lower “sol” layer. Mucus production, secretion and clearance are considered to play a critical role in maintenance of airway health because it maintains hydration in the airway and traps particulates, bacteria, and viruses. Different types of epithelial cells, including secretory cells, and ciliated cells, contribute to the MCC function. Cigarette smoke (CS) contains chemicals and particulates that significantly affect airway secretion. Active and passive CS-induced chronic obstructive pulmonary disease (COPD) is frequently associated with hyperplasia of goblet cells and submucosal glands (SMGs), thus increasing the secretory capacity of the airways that impairs MCC. PMID:22973232

  9. Effects of thoracic squeezing on airway secretion removal in mechanically ventilated patients

    PubMed Central

    Yousefnia-Darzi, Farkhondeh; Hasavari, Farideh; Khaleghdoost, Tahereh; Kazemnezhad-Leyli, Ehsan; Khalili, Malahat

    2016-01-01

    Background: Accumulation of secretions in the airways of patients with an endotracheal tube and mechanical ventilation will have serious consequences. One of the most common methods of airway clearance is endotracheal suctioning. In order to facilitate discharge of airway secretion resulting in promotion of gas exchange, chest physiotherapy techniques can be used at the time of expiration before suction. Materials and Methods: In this clinical trial with a cross-over design, 50 mechanically ventilated patients admitted to intensive care units (ICUs) were randomly divided into two groups of thoracic squeezing. In each patient, two interventions of endotracheal suctioning were conducted, one with and the other without thoracic squeezing during exhalation, with a 3 h gap between the two interventions and an elapse of three respiratory cycles between the number of compressions. Sputum secreted was collected in a container connected to a suction catheter and weighed. Data were recorded in data gathering forms and analyzed using descriptive and inferential statistics (Wilcoxon and independent t-test, Chi-square) in SPSS version 16. Results: Findings showed that the mean weight of the suction secretions removed from airway without thoracic squeezing was 1.35 g and that of suction secretions removed by thoracic squeezing was 1.94 g. Wilcoxon test showed a significant difference regarding the rate of secretion between the two techniques (P = 0.003). Conclusions: According to the study findings, endotracheal suction with thoracic squeezing on expiration helps airway secretion discharge more than suction alone in patients on mechanical ventilators and can be used as an effective method. PMID:27186214

  10. Differential expression and characterization of a member of the mucin-associated surface protein family secreted by Trypanosoma cruzi.

    PubMed

    De Pablos, Luis Miguel; González, Gloria González; Solano Parada, Jennifer; Seco Hidalgo, Víctor; Díaz Lozano, Isabel María; Gómez Samblás, María Mercedes; Cruz Bustos, Teresa; Osuna, Antonio

    2011-10-01

    We describe the characterization, purification, expression, and location of a 52-kDa protein secreted during interaction between the metacyclic form of Trypanosoma cruzi and its target host cell. The protein, which we have named MASP52, belongs to the family of mucin-associated surface proteins (MASPs). The highest levels of expression of both the protein and mRNA occur during the metacyclic and bloodstream trypomastigote stages, the forms that infect the vertebrate host cells. The protein is located in the plasma membrane and in the flagellar pockets of the epimastigote, metacyclic, and trypomastigote forms and is secreted into the medium at the point of contact between the parasite and the cell membrane, as well as into the host-cell cytosol during the amastigote stage. IgG antibodies specific against a synthetic peptide corresponding to the catalytic zone of MASP52 significantly reduce the parasite's capacity to infect the host cells. Furthermore, when the protein is adsorbed onto inert particles of bentonite and incubated with a nonphagocytic cell culture, the particles are able to induce endocytosis in the cells, which seems to demonstrate that MASP52 plays a role in a process whereby the trypomastigote forms of the parasite invade the host cell. PMID:21788387

  11. Pseudomonas aeruginosa triggers CFTR-mediated airway surface liquid secretion in swine trachea

    PubMed Central

    Luan, Xiaojie; Campanucci, Verónica A.; Nair, Manoj; Yilmaz, Orhan; Belev, George; Machen, Terry E.; Chapman, Dean; Ianowski, Juan P.

    2014-01-01

    Cystic fibrosis (CF) is an autosomal recessive genetic disorder caused by mutations in the gene encoding for the anion channel cystic fibrosis transmembrane conductance regulator (CFTR). Several organs are affected in CF, but most of the morbidity and mortality comes from lung disease. Recent data show that the initial consequence of CFTR mutation is the failure to eradicate bacteria before the development of inflammation and airway remodeling. Bacterial clearance depends on a layer of airway surface liquid (ASL) consisting of both a mucus layer that traps, kills, and inactivates bacteria and a periciliary liquid layer that keeps the mucus at an optimum distance from the underlying epithelia, to maximize ciliary motility and clearance of bacteria. The airways in CF patients and animal models of CF demonstrate abnormal ASL secretion and reduced antimicrobial properties. Thus, it has been proposed that abnormal ASL secretion in response to bacteria may facilitate the development of the infection and inflammation that characterize CF airway disease. Whether the inhalation of bacteria triggers ASL secretion, and the role of CFTR, have never been tested, however. We developed a synchrotron-based imaging technique to visualize the ASL layer and measure the effect of bacteria on ASL secretion. We show that the introduction of Pseudomonas aeruginosa and other bacteria into the lumen of intact isolated swine tracheas triggers CFTR-dependent ASL secretion by the submucosal glands. This response requires expression of the bacterial protein flagellin. In patients with CF, the inhalation of bacteria would fail to trigger ASL secretion, leading to infection and inflammation. PMID:25136096

  12. Concentration of the antibacterial precursor thiocyanate in cystic fibrosis airway secretions.

    PubMed

    Lorentzen, Daniel; Durairaj, Lakshmi; Pezzulo, Alejandro A; Nakano, Yoko; Launspach, Janice; Stoltz, David A; Zamba, Gideon; McCray, Paul B; Zabner, Joseph; Welsh, Michael J; Nauseef, William M; Bánfi, Botond

    2011-05-01

    A recently discovered enzyme system produces antibacterial hypothiocyanite (OSCN(-)) in the airway lumen by oxidizing the secreted precursor thiocyanate (SCN(-)). Airway epithelial cultures have been shown to secrete SCN(-) in a CFTR-dependent manner. Thus, reduced SCN(-) availability in the airway might contribute to the pathogenesis of cystic fibrosis (CF), a disease caused by mutations in the CFTR gene and characterized by an airway host defense defect. We tested this hypothesis by analyzing the SCN(-) concentration in the nasal airway surface liquid (ASL) of CF patients and non-CF subjects and in the tracheobronchial ASL of CFTR-ΔF508 homozygous pigs and control littermates. In the nasal ASL, the SCN(-) concentration was ~30-fold higher than in serum independent of the CFTR mutation status of the human subject. In the tracheobronchial ASL of CF pigs, the SCN(-) concentration was somewhat reduced. Among human subjects, SCN(-) concentrations in the ASL varied from person to person independent of CFTR expression, and CF patients with high SCN(-) levels had better lung function than those with low SCN(-) levels. Thus, although CFTR can contribute to SCN(-) transport, it is not indispensable for the high SCN(-) concentration in ASL. The correlation between lung function and SCN(-) concentration in CF patients may reflect a beneficial role for SCN(-). PMID:21334431

  13. Concentration of the antibacterial precursor thiocyanate in cystic fibrosis airway secretions

    PubMed Central

    Lorentzen, Daniel; Durairaj, Lakshmi; Pezzulo, Alejandro A.; Nakano, Yoko; Launspach, Janice; Stoltz, David A.; Zamba, Gideon; McCray, Paul B.; Zabner, Joseph; Welsh, Michael J.; Nauseef, William M.; Bánfi, Botond

    2011-01-01

    A recently discovered enzyme system produces antibacterial hypothiocyanite (OSCN−) in the airway lumen by oxidizing the secreted precursor thiocyanate (SCN−). Airway epithelial cultures have been shown to secrete SCN− in a CFTR-dependent manner. Thus, reduced SCN− availability in the airway might contribute to the pathogenesis of cystic fibrosis (CF), a disease caused by mutations in the CFTR gene and characterized by an airway host defense defect. We tested this hypothesis by analyzing the SCN− concentration in the nasal airway surface liquid (ASL) of CF patients and non-CF subjects, and in the tracheobronchial ASL of CFTR-ΔF508 homozygous pigs and control littermates. In the nasal ASL, the SCN− concentration was ~30-fold higher than in serum independently of the CFTR mutation status of the human subject. In the tracheobronchial ASL of CF pigs, the SCN− concentration was somewhat reduced. Among human subjects, SCN− concentrations in the ASL varied from person to person independent of CFTR expression, and CF patients with high SCN− levels had better lung function than those with low SCN− levels. Thus, although CFTR can contribute to SCN− transport, it is not indispensable for the high SCN− concentration in ASL. The correlation between lung function and SCN− concentration in CF patients may reflect a beneficial role for SCN−. PMID:21334431

  14. Sex Steroids Influence Brain-Derived Neurotropic Factor Secretion From Human Airway Smooth Muscle Cells.

    PubMed

    Wang, Sheng-Yu; Freeman, Michelle R; Sathish, Venkatachalem; Thompson, Michael A; Pabelick, Christina M; Prakash, Y S

    2016-07-01

    Brain derived neurotropic factor (BDNF) is emerging as an important player in airway inflammation, remodeling, and hyperreactivity. Separately, there is increasing evidence that sex hormones contribute to pathophysiology in the lung. BDNF and sex steroid signaling are thought to be intricately linked in the brain. There is currently little information on BDNF and sex steroid interactions in the airway but is relevant to understanding growth factor signaling in the context of asthma in men versus women. In this study, we assessed the effect of sex steroids on BDNF expression and secretion in human airway smooth muscle (ASM). Human ASM was treated with estrogen (E2 ) or testosterone (T, 10 nM each) and intracellular BDNF and secreted BDNF measured. E2 and T significantly reduced secretion of BDNF; effects prevented by estrogen and androgen receptor inhibitor, ICI 182,780 (1 μM), and flutamide (10 μM), respectively. Interestingly, no significant changes were observed in intracellular BDNF mRNA or protein expression. High affinity BDNF receptor, TrkB, was not altered by E2 or T. E2 (but not T) significantly increased intracellular cyclic AMP levels. Notably, Epac1 and Epac2 expression were significantly reduced by E2 and T. Furthermore, SNARE complex protein SNAP25 was decreased. Overall, these novel data suggest that physiologically relevant concentrations of E2 or T inhibit BDNF secretion in human ASM, suggesting a potential interaction of sex steroids with BDNF in the airway that is different from brain. The relevance of sex steroid-BDNF interactions may lie in their overall contribution to airway diseases such as asthma. J. Cell. Physiol. 231: 1586-1592, 2016. © 2015 Wiley Periodicals, Inc. PMID:26566264

  15. Mitotic Asynchrony Induces Transforming Growth Factor-β1 Secretion from Airway Epithelium

    PubMed Central

    Alcala, Sarah E.; Benton, Angela S.; Watson, Alan M.; Kureshi, Suraiya; Reeves, Erica M. K.; Damsker, Jesse; Wang, Zuyi; Nagaraju, Kanneboyina; Anderson, Julia; Williams, Aaron M.; Lee, Amber J. Y.; Hayes, Kathleen; Rose, Mary C.; Hoffman, Eric P.

    2014-01-01

    We recently proposed that mitotic asynchrony in repairing tissue may underlie chronic inflammation and fibrosis, where immune cell infiltration is secondary to proinflammatory cross-talk among asynchronously repairing adjacent tissues. Building on our previous finding that mitotic asynchrony is associated with proinflammatory/fibrotic cytokine secretion (e.g., transforming growth factor [TGF]-β1), here we provide evidence supporting cause-and-effect. Under normal conditions, primary airway epithelial basal cell populations undergo mitosis synchronously and do not secrete proinflammatory or profibrotic cytokines. However, when pairs of nonasthmatic cultures were mitotically synchronized at 12 hours off-set and then combined, the mixed cell populations secreted elevated levels of TGF-β1. This shows that mitotic asynchrony is not only associated with but is also causative of TGF-β1 secretion. The secreted cytokines and other mediators from asthmatic cells were not the cause of asynchronous regeneration; synchronously mitotic nonasthmatic epithelia exposed to conditioned media from asthmatic cells did not show changes in mitotic synchrony. We also tested if resynchronization of regenerating asthmatic airway epithelia reduces TGF-β1 secretion and found that pulse-dosed dexamethasone, simvastatin, and aphidicolin were all effective. We therefore propose a new model for chronic inflammatory and fibrotic conditions where an underlying factor is mitotic asynchrony. PMID:24669775

  16. The tyrosine phosphatase, SHP-1, is involved in bronchial mucin production during oxidative stress.

    PubMed

    Jang, Min Kyoung; Kim, Sae-Hoon; Lee, Ki-Young; Kim, Tae-Bum; Moon, Keun Ae; Park, Chan Sun; Bae, Yun Jeong; Zhu, Zhou; Moon, Hee-Bom; Cho, You Sook

    2010-02-26

    Mucus hypersecretion is a clinically important manifestation of chronic inflammatory airway diseases, such as asthma and Chronic obstructive pulmonary disease (COPD). Mucin production in airway epithelia is increased under conditions of oxidative stress. Src homology 2 domain-containing protein tyrosine phosphatase (SHP)-1 suppression is related to the development of airway inflammation and increased ROS levels. In this study, we investigated the role of SHP-1 in mucin secretion triggered by oxidative stress. Human lung mucoepidermoid H292 carcinoma cells were transfected with specific siRNA to eliminate SHP-1 gene expression. Cultured cells were treated with hydrogen peroxide (H(2)O(2)), and Mucin 5AC(MUC5AC) gene expression and mucin production were determined. Activation of p38 mitogen activated protein kinase (MAPK) in association with MUC5AC production was evaluated. N-acetylcysteine (NAC) was employed to determine whether antioxidants could block MUC5AC production. To establish the precise role of p38, mucin expression was observed after pre-treatment of SHP-1-depleted H292 cells with the p38 chemical blocker. We investigated the in vivo effects of oxidative stress on airway mucus production in SHP-1-deficient heterozygous (mev/+) mice. MUC5AC expression was enhanced in SHP-1 knockdown H292 cells exposed to H(2)O(2), compared to that in control cells. The ratio between phosphorylated and total p38 was significantly increased in SHP-1-deficient cells under oxidative stress. Pre-treatment with NAC suppressed both MUC5AC production and p38 activation. Blockage of p38 MAPK led to suppression of MUC5AC mRNA expression. Notably, mucin production was enhanced in the airway epithelia of mev/+ mice exposed to oxidative stress. Our results clearly indicate that SHP-1 plays an important role in airway mucin production through regulating oxidative stress. PMID:20117097

  17. Bicarbonate and chloride secretion in Calu-3 human airway epithelial cells.

    PubMed

    Devor, D C; Singh, A K; Lambert, L C; DeLuca, A; Frizzell, R A; Bridges, R J

    1999-05-01

    Serous cells are the predominant site of cystic fibrosis transmembrane conductance regulator expression in the airways, and they make a significant contribution to the volume, composition, and consistency of the submucosal gland secretions. We have employed the human airway serous cell line Calu-3 as a model system to investigate the mechanisms of serous cell anion secretion. Forskolin-stimulated Calu-3 cells secrete HCO-3 by a Cl-offdependent, serosal Na+-dependent, serosal bumetanide-insensitive, and serosal 4,4'-dinitrostilben-2,2'-disulfonic acid (DNDS)-sensitive, electrogenic mechanism as judged by transepithelial currents, isotopic fluxes, and the results of ion substitution, pharmacology, and pH studies. Similar studies revealed that stimulation of Calu-3 cells with 1-ethyl-2-benzimidazolinone (1-EBIO), an activator of basolateral membrane Ca2+-activated K+ channels, reduced HCO-3 secretion and caused the secretion of Cl- by a bumetanide-sensitive, electrogenic mechanism. Nystatin permeabilization of Calu-3 monolayers demonstrated 1-EBIO activated a charybdotoxin- and clotrimazole- inhibited basolateral membrane K+ current. Patch-clamp studies confirmed the presence of an intermediate conductance inwardly rectified K+ channel with this pharmacological profile. We propose that hyperpolarization of the basolateral membrane voltage elicits a switch from HCO-3 secretion to Cl- secretion because the uptake of HCO-3 across the basolateral membrane is mediated by a 4,4 '-dinitrostilben-2,2'-disulfonic acid (DNDS)-sensitive Na+:HCO-3 cotransporter. Since the stoichiometry reported for Na+:HCO-3 cotransport is 1:2 or 1:3, hyperpolarization of the basolateral membrane potential by 1-EBIO would inhibit HCO-3 entry and favor the secretion of Cl-. Therefore, differential regulation of the basolateral membrane K+ conductance by secretory agonists could provide a means of stimulating HCO-3 and Cl- secretion. In this context, cystic fibrosis transmembrane conductance

  18. Analysis of airway secretions in a model of sulfur dioxide induced chronic obstructive pulmonary disease (COPD)

    PubMed Central

    Wagner, Ulrich; Staats, Petra; Fehmann, Hans-Christoph; Fischer, Axel; Welte, Tobias; Groneberg, David A

    2006-01-01

    Hypersecretion and chronic phlegm are major symptoms of chronic obstructive pulmonary disease (COPD) but animal models of COPD with a defined functional hypersecretion have not been established so far. To identify an animal model of combined morphological signs of airway inflammation and functional hypersecretion, rats were continuously exposed to different levels of sulfur dioxide (SO2, 5 ppm, 10 ppm, 20 ppm, 40 ppm, 80 ppm) for 3 (short-term) or 20–25 (long-term) days. Histology revealed a dose-dependent increase in edema formation and inflammatory cell infiltration in short-term-exposed animals. The submucosal edema was replaced by fibrosis after long-term-exposure. The basal secretory activity was only significantly increased in the 20 ppm group. Also, stimulated secretion was significantly increased only after exposure to 20 ppm. BrdU-assays and AgNOR-analysis demonstrated cellular metaplasia and glandular hypertrophy rather than hyperplasia as the underlying morphological correlate of the hypersecretion. In summary, SO2-exposure can lead to characteristic airway remodeling and changes in mucus secretion in rats. As only long-term exposure to 20 ppm leads to a combination of hypersecretion and airway inflammation, only this mode of exposure should be used to mimic human COPD. Concentrations less or higher than 20 ppm or short term exposure do not induce the respiratory symptom of hypersecretion. The present model may be used to characterize the effects of new compounds on mucus secretion in the background of experimental COPD. PMID:16759388

  19. A new paradigm in respiratory hygiene: increasing the cohesivity of airway secretions to improve cough interaction and reduce aerosol dispersion

    PubMed Central

    Zayas, Gustavo; Dimitry, John; Zayas, Ana; O'Brien, Darryl; King, Malcolm

    2005-01-01

    Background Infectious respiratory diseases are transmitted to non-infected subjects when an infected person expels pathogenic microorganisms to the surrounding environment when coughing or sneezing. When the airway mucus layer interacts with high-speed airflow, droplets are expelled as aerosol; their concentration and size distribution may each play an important role in disease transmission. Our goal is to reduce the aerosolizability of respiratory secretions while interfering only minimally with normal mucus clearance using agents capable of increasing crosslinking in the mucin glycoprotein network. Methods We exposed mucus simulants (MS) to airflow in a simulated cough machine (SCM). The MS ranged from non-viscous, non-elastic substances (water) to MS of varying degrees of viscosity and elasticity. Mucociliary clearance of the MS was assessed on the frog palate, elasticity in the Filancemeter and the aerosol pattern in a "bulls-eye" target. The sample loaded was weighed before and after each cough maneuver. We tested two mucomodulators: sodium tetraborate (XL"B") and calcium chloride (XL "C"). Results Mucociliary transport was close to normal speed in viscoelastic samples compared to non-elastic, non-viscous or viscous-only samples. Spinnability ranged from 2.5 ± 0.6 to 50.9 ± 6.9 cm, and the amount of MS expelled from the SCM increased from 47 % to 96 % adding 1.5 μL to 150 μL of XL "B". Concurrently, particles were inversely reduced to almost disappear from the aerosolization pattern. Conclusion The aerosolizability of MS was modified by increasing its cohesivity, thereby reducing the number of particles expelled from the SCM while interfering minimally with its clearance on the frog palate. An unexpected finding is that MS crosslinking increased "expectoration". PMID:16138926

  20. Site-specific O-Glycosylation on the MUC2 Mucin Protein Inhibits Cleavage by the Porphyromonas gingivalis Secreted Cysteine Protease (RgpB)*

    PubMed Central

    van der Post, Sjoerd; Subramani, Durai B.; Bäckström, Malin; Johansson, Malin E. V.; Vester-Christensen, Malene B.; Mandel, Ulla; Bennett, Eric P.; Clausen, Henrik; Dahlén, Gunnar; Sroka, Aneta; Potempa, Jan; Hansson, Gunnar C.

    2013-01-01

    The colonic epithelial surface is protected by an inner mucus layer that the commensal microflora cannot penetrate. We previously demonstrated that Entamoeba histolytica secretes a protease capable of dissolving this layer that is required for parasite penetration. Here, we asked whether there are bacteria that can secrete similar proteases. We screened bacterial culture supernatants for such activity using recombinant fragments of the MUC2 mucin, the major structural component, and the only gel-forming mucin in the colonic mucus. MUC2 has two central heavily O-glycosylated mucin domains that are protease-resistant and has cysteine-rich N and C termini responsible for polymerization. Culture supernatants of Porphyromonas gingivalis, a bacterium that secretes proteases responsible for periodontitis, cleaved the MUC2 C-terminal region, whereas the N-terminal region was unaffected. The active enzyme was isolated and identified as Arg-gingipain B (RgpB). Two cleavage sites were localized to IR↓TT and NR↓QA. IR↓TT cleavage will disrupt the MUC2 polymers. Because this site has two potential O-glycosylation sites, we tested whether recombinant GalNAc-transferases (GalNAc-Ts) could glycosylate a synthetic peptide covering the IRTT sequence. Only GalNAc-T3 was able to glycosylate the second Thr in IRTT, rendering the sequence resistant to cleavage by RgpB. Furthermore, when GalNAc-T3 was expressed in CHO cells expressing the MUC2 C terminus, the second threonine was glycosylated, and the protein became resistant to RgpB cleavage. These findings suggest that bacteria can produce proteases capable of dissolving the inner protective mucus layer by specific cleavages in the MUC2 mucin and that this cleavage can be modulated by site-specific O-glycosylation. PMID:23546879

  1. cAMP stimulation of HCO3- secretion across airway epithelia.

    PubMed

    Welsh, M J; Smith, J J

    2001-07-01

    To test for the presence of HCO(3)(-) transport across airway epithelia, we measured short-circuit current in primary cultures of canine and human airway epithelia bathed in a Cl(-)-free, HCO(3)(-)/CO(2)-buffered solution. cAMP agonists stimulated a secretory current that was likely carried by HCO(3)(-) because it was absent in HCO(3)(-)-free solutions. In addition, the cAMP-stimulated current was inhibited by the carbonic anhydrase inhibitor, acetazolamide, and by the apical addition of a blocker of cystic fibrosis transmembrane conductance regulator (CFTR), diphenylamine-2-carboxylate. The current was dependent on Na(+) because it was inhibited by removing Na(+) from the submucosal solution and by inhibition of the Na(+)-K(+)-ATPase with ouabain. The cAMP-stimulated current was absent in cystic fibrosis (CF) airway epithelia. These data suggest that cAMP agonists can stimulate HCO(3)(-) secretion across airway epithelia and that CFTR may provide a conductive pathway for HCO(3)(-) movement across the apical membrane. PMID:11875274

  2. Human airway smooth muscle cells secrete amphiregulin via bradykinin/COX-2/PGE2, inducing COX-2, CXCL8, and VEGF expression in airway epithelial cells

    PubMed Central

    Knox, Alan J.

    2015-01-01

    Human airway smooth muscle cells (HASMC) contribute to asthma pathophysiology through an increased smooth muscle mass and elevated cytokine/chemokine output. Little is known about how HASMC and the airway epithelium interact to regulate chronic airway inflammation and remodeling. Amphiregulin is a member of the family of epidermal growth factor receptor (EGFR) agonists with cell growth and proinflammatory roles and increased expression in the lungs of asthma patients. Here we show that bradykinin (BK) stimulation of HASMC increases amphiregulin secretion in a mechanism dependent on BK-induced COX-2 expression, increased PGE2 output, and the stimulation of HASMC EP2 and EP4 receptors. Conditioned medium from BK treated HASMC induced CXCL8, VEGF, and COX-2 mRNA and protein accumulation in airway epithelial cells, which were blocked by anti-amphiregulin antibodies and amphiregulin siRNA, suggesting a paracrine effect of HASMC-derived amphiregulin on airway epithelial cells. Consistent with this, recombinant amphiregulin induced CXCL8, VEGF, and COX-2 in airway epithelial cells. Finally, we found that conditioned media from amphiregulin-stimulated airway epithelial cells induced amphiregulin expression in HASMC and that this was dependent on airway epithelial cell COX-2 activity. Our study provides evidence of a dynamic axis of interaction between HASMC and epithelial cells that amplifies CXCL8, VEGF, COX-2, and amphiregulin production. PMID:26047642

  3. Control of airway tube diameter and integrity by secreted chitin-binding proteins in Drosophila.

    PubMed

    Tiklová, Katarína; Tsarouhas, Vasilios; Samakovlis, Christos

    2013-01-01

    The transporting function of many branched tubular networks like our lungs and circulatory system depend on the sizes and shapes of their branches. Understanding the mechanisms of tube size control during organ development may offer new insights into a variety of human pathologies associated with stenoses or cystic dilations in tubular organs. Here, we present the first secreted luminal proteins involved in tube diametric expansion in the Drosophila airways. obst-A and gasp are conserved among insect species and encode secreted proteins with chitin binding domains. We show that the widely used tracheal marker 2A12, recognizes the Gasp protein. Analysis of obst-A and gasp single mutants and obst-A; gasp double mutant shows that both genes are primarily required for airway tube dilation. Similarly, Obst-A and Gasp control epidermal cuticle integrity and larval growth. The assembly of the apical chitinous matrix of the airway tubes is defective in gasp and obst-A mutants. The defects become exaggerated in double mutants indicating that the genes have partially redundant functions in chitin structure modification. The phenotypes in luminal chitin assembly in the airway tubes are accompanied by a corresponding reduction in tube diameter in the mutants. Conversely, overexpression of Obst-A and Gasp causes irregular tube expansion and interferes with tube maturation. Our results suggest that the luminal levels of matrix binding proteins determine the extent of diametric growth. We propose that Obst-A and Gasp organize luminal matrix assembly, which in turn controls the apical shapes of adjacent cells during tube diameter expansion. PMID:23826295

  4. Neural control of submucosal gland and apical membrane secretions in airways

    PubMed Central

    Cuthbert, Alan W; Murthy, Meena; Darlington, Alexander P S

    2015-01-01

    The mechanisms that lay behind the low-level secretions from airway submucosal glands and the surface epithelium in the absence of external innervation have been investigated in small areas (1.0–1.5 cm2) of mucosa from sheep tracheas, freshly collected from a local abattoir. Glandular secretion was measured by an optical method while short circuit current was used as a measure of surface secretion. Activation of neurones in the intrinsic nerve net by veratrine alkaloids caused an immediate increase in both glandular secretion and short circuit current, both effects being blocked by the addition of tetrodotoxin. However, agents known to be acting directly on the glands, such as muscarinic agonists (e.g., carbachol) or adenylate cyclase activators (e.g., forskolin) were not influenced by tetrodotoxin. The toxin alone had no discernable effect on the low-level basal secretion shown by unstimulated glands. Calu-3 cell monolayers, generally agreed to be a surrogate for the secretory cells of submucosal glands, showed no sensitivity to veratrine alkaloids, strengthening the view that the veratrine-like drugs acted exclusively on the intrinsic nerve net. The data are discussed in relation way in which transplanted lungs can maintain mucociliary clearance and hence a sterile environment in the absence of external innervation, as in transplanted lungs. PMID:26059031

  5. Dietary threonine response of Pekin ducks from hatch to 14 d of age based on performance, serology, and intestinal mucin secretion.

    PubMed

    Zhang, Q; Zeng, Q F; Cotter, P; Applegate, T J

    2016-06-01

    Two experiments were conducted to determine the dietary threonine (Thr) requirement of Pekin ducks from hatch to 14 d of age. In experiment 1, practical corn-soybean meal diets were formulated to contain 0.78, 0.84, 0.90, 0.96, and 1.02% Thr (0.74, 0.83, 0.88, 0.92, and 1.00% Thr on an analyzed basis). In experiment 2, corn-soybean meal diets supplemented with 11 crystalline amino acids were formulated to contain 0.60, 0.70, 0.80, 0.90, 1.00, and 1.10% Thr (0.60, 0.75, 0.89, 0.95, 1.01, and 1.09% Thr on an analyzed basis). In both experiments, diets were fed to 8 replicate cages with 6 male ducks per cage. Body weight and feed intake from each cage were recorded weekly. At 14 d of age, breast meat, ileal digesta, and serum were collected to determine breast meat yield, mucin secretion, and serology parameters. In both studies, the estimated Thr requirement (expressed as % dietary Thr basis) for 14 d BW and BW gain (BWG) by quadratic broken-line (QBL) regression were similar, which were 0.87 and 0.86%, respectively. Additional measures in both experiments resulted in Thr requirements via QBL regression in rank order of crude mucin secretion < breast meat yield < serum immune activity. Summing up the estimates from both studies, the Thr requirement ranged from a low of 0.81% to maximize feed intake (FI) to a high of 1.00% to maximize serum Rb L100 by QBL regression. Correspondingly, the Thr requirement varied between a low of 0.90% to maximize crude mucin secretion on a dry matter intake (DMI) basis and a high of 0.98% to maximize feed-to-gain when using quadratic regression. PMID:26944967

  6. Airway Gland Structure and Function.

    PubMed

    Widdicombe, Jonathan H; Wine, Jeffrey J

    2015-10-01

    Submucosal glands contribute to airway surface liquid (ASL), a film that protects all airway surfaces. Glandular mucus comprises electrolytes, water, the gel-forming mucin MUC5B, and hundreds of different proteins with diverse protective functions. Gland volume per unit area of mucosal surface correlates positively with impaction rate of inhaled particles. In human main bronchi, the volume of the glands is ∼ 50 times that of surface goblet cells, but the glands diminish in size and frequency distally. ASL and its trapped particles are removed from the airways by mucociliary transport. Airway glands have a tubuloacinar structure, with a single terminal duct, a nonciliated collecting duct, then branching secretory tubules lined with mucous cells and ending in serous acini. They allow for a massive increase in numbers of mucus-producing cells without replacing surface ciliated cells. Active secretion of Cl(-) and HCO3 (-) by serous cells produces most of the fluid of gland secretions. Glands are densely innervated by tonically active, mutually excitatory airway intrinsic neurons. Most gland mucus is secreted constitutively in vivo, with large, transient increases produced by emergency reflex drive from the vagus. Elevations of [cAMP]i and [Ca(2+)]i coordinate electrolyte and macromolecular secretion and probably occur together for baseline activity in vivo, with cholinergic elevation of [Ca(2+)]i being mainly responsive for transient increases in secretion. Altered submucosal gland function contributes to the pathology of all obstructive diseases, but is an early stage of pathogenesis only in cystic fibrosis. PMID:26336032

  7. Host mucin glycosylation plays a role in bacterial adhesion in lungs of individuals with cystic fibrosis.

    PubMed

    Venkatakrishnan, Vignesh; Packer, Nicolle H; Thaysen-Andersen, Morten

    2013-10-01

    Malfunction of the cell surface glycoprotein, cystic fibrosis transmembrane conductance regulator, is the molecular hallmark of cystic fibrosis (CF), causing salt imbalance across the lung epithelium and biochemical and biophysical alterations of the mucous secretion and airway surfaces. Abnormal glycosylation of both secreted and membrane-tethered airway mucins in CF hosts are reported by a substantial body of literature and correlates with bacterial infection and inflammation in CF airways, features that are linked to the CF pathology. It is established that Pseudomonas aeruginosa and other CF-typic bacteria use the altered host mucin glycosylation as receptors for adhesion by dedicated lectins and adhesins recognizing an array of the aberrantly expressed glycan determinants. This review aims to describe the aberrant mucin glycosylation phenotype observed in CF airways relative to the non-CF equivalent by summarizing the wealth of literature on this topic. The possible causes and effects of altered glycosylation in the respiratory system are discussed. Specific attention is given to the adhesion mechanisms of the opportunistic P. aeruginosa, which utilizes the molecular alterations of the lung to gain access to the normally sterile airways. Finally, the emerging glycosylation-based therapeutics that show promising potential for reducing bacterial infection in individuals with CF by molecular mimicry mechanisms are discussed. PMID:24138697

  8. Mucin overproduction in chronic inflammatory lung disease

    PubMed Central

    Hauber, Hans-Peter; Foley, Susan C; Hamid, Qutayba

    2006-01-01

    Mucus overproduction and hypersecretion are commonly observed in chronic inflammatory lung disease. Mucins are gel-forming glycoproteins that can be stimulated by a variety of mediators. The present review addresses the mechanisms involved in the upregulation of secreted mucins. Mucin induction by neutrophil elastase, bacteria, cytokines, growth factors, smoke and cystic fibrosis transmembrane conductance regulator malfunction are also discussed. PMID:16983448

  9. Airway Surface Dehydration Aggravates Cigarette Smoke-Induced Hallmarks of COPD in Mice

    PubMed Central

    Seys, Leen J. M.; Verhamme, Fien M.; Dupont, Lisa L.; Desauter, Elke; Duerr, Julia; Seyhan Agircan, Ayca; Conickx, Griet; Joos, Guy F.; Brusselle, Guy G.

    2015-01-01

    Introduction Airway surface dehydration, caused by an imbalance between secretion and absorption of ions and fluid across the epithelium and/or increased epithelial mucin secretion, impairs mucociliary clearance. Recent evidence suggests that this mechanism may be implicated in chronic obstructive pulmonary disease (COPD). However, the role of airway surface dehydration in the pathogenesis of cigarette smoke (CS)-induced COPD remains unknown. Objective We aimed to investigate in vivo the effect of airway surface dehydration on several CS-induced hallmarks of COPD in mice with airway-specific overexpression of the β-subunit of the epithelial Na+ channel (βENaC). Methods βENaC-Tg mice and wild-type (WT) littermates were exposed to air or CS for 4 or 8 weeks. Pathological hallmarks of COPD, including goblet cell metaplasia, mucin expression, pulmonary inflammation, lymphoid follicles, emphysema and airway wall remodelling were determined and lung function was measured. Results Airway surface dehydration in βENaC-Tg mice aggravated CS-induced airway inflammation, mucin expression and destruction of alveolar walls and accelerated the formation of pulmonary lymphoid follicles. Moreover, lung function measurements demonstrated an increased compliance and total lung capacity and a lower resistance and hysteresis in βENaC-Tg mice, compared to WT mice. CS exposure further altered lung function measurements. Conclusions We conclude that airway surface dehydration is a risk factor that aggravates CS-induced hallmarks of COPD. PMID:26066648

  10. Basolateral K+ channels in airway epithelia. II. Role in Cl- secretion and evidence for two types of K+ channel

    SciTech Connect

    McCann, J.D.; Welsh, M.J. )

    1990-06-01

    We previously described a Ca2(+)-activated K+ channel (KCLIC) in airway epithelial cells. To determine whether the KCLIC channel is a basolateral membrane channel and to understand its role in Cl- secretion, we studied airway epithelial cells grown on permeable supports. When cells were stimulated with A23187, charybdotoxin (ChTX) inhibited Cl- secretion and 86Rb efflux at the same concentrations, indicating that the KCLIC channel is required for Ca2(+)-stimulated Cl- secretion. We also investigated the function of K+ channels in adenosine 3',5'-cyclic monophosphate-stimulated secretion. Addition of isoproterenol caused a biphasic increase in Cl- secretion; the time course of the transient component correlated with the time course of the isoproterenol-induced increase in Ca2+ concentration (( Ca2+)c). ChTX inhibited the transient component, but not the prolonged component of secretion; Ba2+ inhibited the sustained component. These results suggest that when cells are grown on permeable supports isoproterenol-induced secretion depends on activation of two types of K+ channel: the KCLIC channel that is stimulated initially and a ChTX-insensitive K+ channel that is stimulated during sustained secretion. This conclusion was supported by measurement of 86Rb efflux from cell monolayers.

  11. Pharmacological analysis of epithelial chloride secretion mechanisms in adult murine airways.

    PubMed

    Gianotti, Ambra; Ferrera, Loretta; Philp, Amber R; Caci, Emanuela; Zegarra-Moran, Olga; Galietta, Luis J V; Flores, Carlos A

    2016-06-15

    Defective epithelial chloride secretion occurs in humans with cystic fibrosis (CF), a genetic defect due to loss of function of CFTR, a cAMP-activated chloride channel. In the airways, absence of an active CFTR causes a severe lung disease. In mice, genetic ablation of CFTR function does not result in similar lung pathology. This may be due to the expression of an alternative chloride channel which is activated by calcium. The most probable protein performing this function is TMEM16A, a calcium-activated chloride channel (CaCC). Our aim was to assess the relative contribution of CFTR and TMEM16A to chloride secretion in adult mouse trachea. For this purpose we tested pharmacological inhibitors of chloride channels in normal and CF mice. The amplitude of the cAMP-activated current was similar in both types of animals and was not affected by a selective CFTR inhibitor. In contrast, a CaCC inhibitor (CaCCinh-A01) strongly blocked the cAMP-activated current as well as the calcium-activated chloride secretion triggered by apical UTP. Although control experiments revealed that CaCCinh-A01 also shows inhibitory activity on CFTR, our results indicate that transepithelial chloride secretion in adult mouse trachea is independent of CFTR and that another channel, possibly TMEM16A, performs both cAMP- and calcium-activated chloride transport. The prevalent function of a non-CFTR channel may explain the absence of a defect in chloride transport in CF mice. PMID:27063443

  12. Surfactant synthesis, secretion, and function in alveoli and small airways. Review of the physiologic basis for pharmacologic intervention.

    PubMed

    Mason, R J

    1987-01-01

    Surface-active material is known to lower surface tension at the air/liquid interface and provide alveolar stability. Less well appreciated is the potential role of surface-active material in maintaining the patency of small airways and in transporting particles from the alveolar surface to the small airways. The interactions between the two dominant secretory cells in the terminal lung units, i.e., the alveolar type II cell and the Clara cell, are just starting to be discovered. The biochemical signals for secretion of surface-active material in vivo are still not known. The dominant physiologic stimulus is hyperventilation. Secretion in vitro is stimulated by activation of protein-kinase C (tetradecanoyl phorbol acetate), protein-kinase A (cyclic AMP, beta-adrenergic agonists, cholera toxin), and calcium ionophores (A23187 or ionomycin). The biochemical basis for secretion will be discussed. PMID:2885907

  13. Airway Hyperresponsiveness in Asthma Model Occurs Independently of Secretion of β1 Integrins in Airway Wall and Focal Adhesions Proteins Down Regulation.

    PubMed

    Álvarez-Santos, Mayra; Carbajal, Verónica; Tellez-Jiménez, Olivia; Martínez-Cordero, Erasmo; Ruiz, Victor; Hernández-Pando, Rogelio; Lascurain, Ricardo; Santibañez-Salgado, Alfredo; Bazan-Perkins, Blanca

    2016-10-01

    The extracellular domains of some membrane proteins can be shed from the cell. A similar phenomenon occurs with β1 integrins (α1β1 and α2β1) in guinea pig. The putative role of β1 integrin subunit alterations due to shedding in airway smooth muscle (ASM) in an allergic asthma model was evaluated. Guinea pigs were sensitized and challenged with antigen. Antigenic challenges induced bronchoobstruction and hyperresponsiveness at the third antigenic challenge. Immunohistochemistry and immunoelectronmicroscopy studies showed that the cytosolic and extracellular domains of the β1 integrin subunit shared the same distribution in airway structures in both groups. Various polypeptides with similar molecular weights were detected with both the cytosolic and extracellular β1 integrin subunit antibodies in isolated airway myocytes and the connective tissue that surrounds the ASM bundle. Flow cytometry and Western blot studies showed that the expression of cytosolic and extracellular β1 integrin subunit domains in ASM was similar between groups. An increment of ITGB1 mRNA in ASM was observed in the asthma model group. RACE-PCR of ITGB1 in ASM did not show splicing variants. The expression levels of integrin-linked kinase (ILK) and paxillin diminished in the asthma model, but not talin. The levels of phosphorylation of myosin phosphatase target subunit 1 (MYPT1) at Thr(696) increased in asthma model. Our work suggests that β1 integrin is secreted in guinea pig airway wall. This secretion is not altered in asthma model; nevertheless, β1 integrin cytodomain assembly proteins in focal cell adhesions in which ILK and paxillin are involved are altered in asthma model. J. Cell. Biochem. 117: 2385-2396, 2016. © 2016 Wiley Periodicals, Inc. PMID:26969873

  14. Mucin-Based Vaccines

    NASA Astrophysics Data System (ADS)

    Richardson, Jonathan P.; MacMillan, Derek

    Mucins are heavily O-glycosylated cell surface and secreted glycoproteins . In addition to orchestrating cell-extracellular matrix and cell-cell interactions in healthy organisms mucins are also the major carriers of altered glycosylation in carcinomas. Tumor-associated antigens displayed by cancer cells comprise oligosaccharide and glycopeptide motifs not encountered in the same locale or at the same frequency in healthy cells, and potentially confer a selective advantage to the tumor. Frequently tumor-associated antigens are under-glycosylated and prematurely sialylated, and it is these relatively simple saccharide and glycopeptide structures that have been targeted to serve as drug candidates in most cases. A major goal is to assemble glycopeptide vaccine candidates based on partial mucin sequences and displaying tumor-associated antigens that can mount a potent immunological tumor-specific response when, in reality, the tumor has already coerced the immune system into a state of co-existence.

  15. The Role of Bacterial Secretion Systems in the Virulence of Gram-Negative Airway Pathogens Associated with Cystic Fibrosis

    PubMed Central

    Depluverez, Sofie; Devos, Simon; Devreese, Bart

    2016-01-01

    Cystic fibrosis (CF) is the most common lethal inherited disorder in Caucasians. It is caused by mutation of the CF transmembrane conductance regulator (CFTR) gene. A defect in the CFTR ion channel causes a dramatic change in the composition of the airway surface fluid, leading to a highly viscous mucus layer. In healthy individuals, the majority of bacteria trapped in the mucus layer are removed and destroyed by mucociliary clearance. However, in the lungs of patients with CF, the mucociliary clearance is impaired due to dehydration of the airway surface fluid. As a consequence, patients with CF are highly susceptible to chronic or intermittent pulmonary infections, often causing extensive lung inflammation and damage, accompanied by a decreased life expectancy. This mini review will focus on the different secretion mechanisms used by the major bacterial CF pathogens to release virulence factors, their role in resistance and discusses the potential for therapeutically targeting secretion systems. PMID:27625638

  16. The Role of Bacterial Secretion Systems in the Virulence of Gram-Negative Airway Pathogens Associated with Cystic Fibrosis.

    PubMed

    Depluverez, Sofie; Devos, Simon; Devreese, Bart

    2016-01-01

    Cystic fibrosis (CF) is the most common lethal inherited disorder in Caucasians. It is caused by mutation of the CF transmembrane conductance regulator (CFTR) gene. A defect in the CFTR ion channel causes a dramatic change in the composition of the airway surface fluid, leading to a highly viscous mucus layer. In healthy individuals, the majority of bacteria trapped in the mucus layer are removed and destroyed by mucociliary clearance. However, in the lungs of patients with CF, the mucociliary clearance is impaired due to dehydration of the airway surface fluid. As a consequence, patients with CF are highly susceptible to chronic or intermittent pulmonary infections, often causing extensive lung inflammation and damage, accompanied by a decreased life expectancy. This mini review will focus on the different secretion mechanisms used by the major bacterial CF pathogens to release virulence factors, their role in resistance and discusses the potential for therapeutically targeting secretion systems. PMID:27625638

  17. Bile acids stimulate chloride secretion through CFTR and calcium-activated Cl- channels in Calu-3 airway epithelial cells.

    PubMed

    Hendrick, Siobhán M; Mroz, Magdalena S; Greene, Catherine M; Keely, Stephen J; Harvey, Brian J

    2014-09-01

    Bile acids resulting from the aspiration of gastroesophageal refluxate are often present in the lower airways of people with cystic fibrosis and other respiratory distress diseases. Surprisingly, there is little or no information on the modulation of airway epithelial ion transport by bile acids. The secretory effect of a variety of conjugated and unconjugated secondary bile acids was investigated in Calu-3 airway epithelial cells grown under an air-liquid interface and mounted in Ussing chambers. Electrogenic transepithelial ion transport was measured as short-circuit current (Isc). The taurine-conjugated secondary bile acid, taurodeoxycholic acid (TDCA), was found to be the most potent modulator of basal ion transport. Acute treatment (5 min) of Calu-3 cells with TDCA (25 μM) on the basolateral side caused a stimulation of Isc, and removal of extracellular Cl(-) abolished this response. TDCA produced an increase in the cystic fibrosis transmembrane conductance regulator (CFTR)-dependent current that was abolished by pretreatment with the CFTR inhibitor CFTRinh172. TDCA treatment also increased Cl(-) secretion through calcium-activated chloride (CaCC) channels and increased the Na(+)/K(+) pump current. Acute treatment with TDCA resulted in a rapid cellular influx of Ca(2+) and increased cAMP levels in Calu-3 cells. Bile acid receptor-selective activation with INT-777 revealed TGR5 localized at the basolateral membrane as the receptor involved in TDCA-induced Cl(-) secretion. In summary, we demonstrate for the first time that low concentrations of bile acids can modulate Cl(-) secretion in airway epithelial cells, and this effect is dependent on both the duration and sidedness of exposure to the bile acid. PMID:24993131

  18. Mucin Binding Reduces Colistin Antimicrobial Activity

    PubMed Central

    Huang, Johnny X.; Blaskovich, Mark A. T.; Pelingon, Ruby; Ramu, Soumya; Kavanagh, Angela; Elliott, Alysha G.; Butler, Mark S.

    2015-01-01

    Colistin has found increasing use in treating drug-resistant bacterial lung infections, but potential interactions with pulmonary biomolecules have not been investigated. We postulated that colistin, like aminoglycoside antibiotics, may bind to secretory mucin in sputum or epithelial mucin that lines airways, reducing free drug levels. To test this hypothesis, we measured binding of colistin and other antibiotics to porcine mucin, a family of densely glycosylated proteins used as a surrogate for human sputum and airway mucin. Antibiotics were incubated in dialysis tubing with or without mucin, and concentrations of unbound antibiotics able to penetrate the dialysis tubing were measured over time using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The percentage of antibiotic measured in the dialysate after 4 h in the presence of mucin, relative to the amount without mucin, was 15% for colistin, 16% for polymyxin B, 19% for tobramycin, 52% for ciprofloxacin, and 78% for daptomycin. Antibiotics with the strongest mucin binding had an overall polybasic positive charge, whereas those with comparatively little binding were less basic. When comparing MICs measured with or without added mucin, colistin and polymyxin B showed >100-fold increases in MICs for multiple Gram-negative bacteria. Preclinical evaluation of mucin binding should become a standard procedure when considering the potential pulmonary use of new or existing antibiotics, particularly those with a polybasic overall charge. In the airways, mucin binding may reduce the antibacterial efficacy of inhaled or intravenously administered colistin, and the presence of sub-MIC effective antibiotic concentrations could result in the development of antibiotic resistance. PMID:26169405

  19. Hypercapnia modulates cAMP signalling and cystic fibrosis transmembrane conductance regulator-dependent anion and fluid secretion in airway epithelia.

    PubMed

    Turner, Mark J; Saint-Criq, Vinciane; Patel, Waseema; Ibrahim, Salam H; Verdon, Bernard; Ward, Christopher; Garnett, James P; Tarran, Robert; Cann, Martin J; Gray, Michael A

    2016-03-15

    Hypercapnia is clinically defined as an arterial blood partial pressure of CO2 of above 40 mmHg and is a feature of chronic lung disease. In previous studies we have demonstrated that hypercapnia modulates agonist-stimulated cAMP levels through effects on transmembrane adenylyl cyclase activity. In the airways, cAMP is known to regulate cystic fibrosis transmembrane conductance regulator (CFTR)-mediated anion and fluid secretion, which contributes to airway surface liquid homeostasis. The aim of the current work was to investigate if hypercapnia could modulate cAMP-regulated ion and fluid transport in human airway epithelial cells. We found that acute exposure to hypercapnia significantly reduced forskolin-stimulated elevations in intracellular cAMP as well as both adenosine- and forskolin-stimulated increases in CFTR-dependent transepithelial short-circuit current, in polarised cultures of Calu-3 human airway cells. This CO2 -induced reduction in anion secretion was not due to a decrease in HCO3 (-) transport given that neither a change in CFTR-dependent HCO3 (-) efflux nor Na(+) /HCO3 (-) cotransporter-dependent HCO3 (-) influx were CO2 -sensitive. Hypercapnia also reduced the volume of forskolin-stimulated fluid secretion over 24 h, yet had no effect on the HCO3 (-) content of the secreted fluid. Our data reveal that hypercapnia reduces CFTR-dependent, electrogenic Cl(-) and fluid secretion, but not CFTR-dependent HCO3 (-) secretion, which highlights a differential sensitivity of Cl(-) and HCO3 (-) transporters to raised CO2 in Calu-3 cells. Hypercapnia also reduced forskolin-stimulated CFTR-dependent anion secretion in primary human airway epithelia. Based on current models of airways biology, a reduction in fluid secretion, associated with hypercapnia, would be predicted to have important consequences for airways hydration and the innate defence mechanisms of the lungs. PMID:26574187

  20. Bicarbonate-dependent chloride transport drives fluid secretion by the human airway epithelial cell line Calu-3

    PubMed Central

    Shan, Jiajie; Liao, Jie; Huang, Junwei; Robert, Renaud; Palmer, Melissa L; Fahrenkrug, Scott C; O'Grady, Scott M; Hanrahan, John W

    2012-01-01

    Anion and fluid secretion are both defective in cystic fibrosis (CF); however, the transport mechanisms are not well understood. In this study, Cl− and HCO3− secretion was measured using genetically matched CF transmembrane conductance regulator (CFTR)-deficient and CFTR-expressing cell lines derived from the human airway epithelial cell line Calu-3. Forskolin stimulated the short-circuit current (Isc) across voltage-clamped monolayers, and also increased the equivalent short-circuit current (Ieq) calculated under open-circuit conditions. Isc was equivalent to the HCO3− net flux measured using the pH-stat technique, whereas Ieq was the sum of the Cl− and HCO3− net fluxes. Ieq and HCO3− fluxes were increased by bafilomycin and ZnCl2, suggesting that some secreted HCO3− is neutralized by parallel electrogenic H+ secretion. Ieq and fluid secretion were dependent on the presence of both Na+ and HCO3−. The carbonic anhydrase inhibitor acetazolamide abolished forskolin stimulation of Ieq and HCO3− secretion, suggesting that HCO3− transport under these conditions requires catalysed synthesis of carbonic acid. Cl− was the predominant anion in secretions under all conditions studied and thus drives most of the fluid transport. Nevertheless, 50–70% of Cl− and fluid transport was bumetanide-insensitive, suggesting basolateral Cl− loading by a sodium–potassium–chloride cotransporter 1 (NKCC1)-independent mechanism. Imposing a transepithelial HCO3− gradient across basolaterally permeabilized Calu-3 cells sustained a forskolin-stimulated current, which was sensitive to CFTR inhibitors and drastically reduced in CFTR-deficient cells. Net HCO3− secretion was increased by bilateral Cl− removal and therefore did not require apical Cl−/HCO3− exchange. The results suggest a model in which most HCO3− is recycled basolaterally by exchange with Cl−, and the resulting HCO3−-dependent Cl− transport provides an osmotic driving force for

  1. Role of the cystine-knot motif at the C-terminus of rat mucin protein Muc2 in dimer formation and secretion.

    PubMed Central

    Bell, S L; Xu, G; Forstner, J F

    2001-01-01

    DNA constructs based on the 534-amino-acid C-terminus of rat mucin protein Muc2 (RMC), were transfected into COS cells and the resultant (35)S-labelled dimers and monomers were detected by SDS/PAGE of immunoprecipitates. The cystine-knot construct, encoding the C-terminal 115 amino acids, appeared in cell lysates as a 45 kDa dimer, but was not secreted. A construct, devoid of the cystine knot, failed to form dimers. Site-specific mutagenesis within the cystine knot was performed on a conserved unpaired cysteine (designated Cys-X), which has been implicated in some cystine-knot-containing growth factors as being important for intermolecular disulphide-bond formation. Dimerization of RMC was effectively abolished. Each cysteine (Cys-1-Cys-6) comprising the three intramolecular disulphide bonds of the cystine knot was then mutated. Dimer formation was impaired in each case, although much less so for the Cys-3 mutant than the others. Abnormal high-molecular-mass, disulphide-dependent aggregates formed with mutations Cys-1, Cys-2, Cys-4 and Cys-5(,) and were poorly secreted. It is concluded that the intact cystine-knot domain is essential for dimerization of the C-terminal domain of rat Muc2, and that residue Cys-X in the knot plays a key role. The structural integrity of the cystine knot, maintained by intramolecular bonds Cys-1-Cys-4, Cys-2-Cys-5 and Cys-3-Cys-6, also appears to be important for dimerization, probably by allowing correct positioning of the unpaired Cys-X residue for stable intermolecular cystine-bond formation. PMID:11415450

  2. Mucin Dynamics in Intestinal Bacterial Infection

    PubMed Central

    Lindén, Sara K.; Florin, Timothy H. J.; McGuckin, Michael A.

    2008-01-01

    Background Bacterial gastroenteritis causes morbidity and mortality in humans worldwide. Murine Citrobacter rodentium infection is a model for gastroenteritis caused by the human pathogens enteropathogenic Escherichia coli and enterohaemorrhagic E. coli. Mucin glycoproteins are the main component of the first barrier that bacteria encounter in the intestinal tract. Methodology/Principal Findings Using Immunohistochemistry, we investigated intestinal expression of mucins (Alcian blue/PAS, Muc1, Muc2, Muc4, Muc5AC, Muc13 and Muc3/17) in healthy and C. rodentium infected mice. The majority of the C. rodentium infected mice developed systemic infection and colitis in the mid and distal colon by day 12. C. rodentium bound to the major secreted mucin, Muc2, in vitro, and high numbers of bacteria were found in secreted MUC2 in infected animals in vivo, indicating that mucins may limit bacterial access to the epithelial surface. In the small intestine, caecum and proximal colon, the mucin expression was similar in infected and non-infected animals. In the distal colonic epithelium, all secreted and cell surface mucins decreased with the exception of the Muc1 cell surface mucin which increased after infection (p<0.05). Similarly, during human infection Salmonella St Paul, Campylobacter jejuni and Clostridium difficile induced MUC1 in the colon. Conclusion Major changes in both the cell-surface and secreted mucins occur in response to intestinal infection. PMID:19088856

  3. Bicarbonate and functional CFTR channel are required for proper mucin secretion and link cystic fibrosis with its mucus phenotype

    PubMed Central

    Gustafsson, Jenny K.; Ermund, Anna; Ambort, Daniel; Johansson, Malin E.V.; Nilsson, Harriet E.; Thorell, Kaisa; Hebert, Hans; Sjövall, Henrik

    2012-01-01

    Cystic fibrosis (CF) is caused by a nonfunctional chloride and bicarbonate ion channel (CF transmembrane regulator [CFTR]), but the link to the phenomenon of stagnant mucus is not well understood. Mice lacking functional CFTR (CftrΔ508) have no lung phenotype but show similar ileal problems to humans. We show that the ileal mucosa in CF have a mucus that adhered to the epithelium, was denser, and was less penetrable than that of wild-type mice. The properties of the ileal mucus of CF mice were normalized by secretion into a high concentration sodium bicarbonate buffer (∼100 mM). In addition, bicarbonate added to already formed CF mucus almost completely restored the mucus properties. This knowledge may provide novel therapeutic options for CF. PMID:22711878

  4. The role of airway mucus in pulmonary toxicology.

    PubMed Central

    Samet, J M; Cheng, P W

    1994-01-01

    Airway mucus is a complex airway secretion whose primary function as part of the mucociliary transport mechanism is to to serve as renewable and transportable barrier against inhaled particulates and toxic agents. The rheologic properties necessary for this function are imparted by glycoproteins, or mucins. Some respiratory disease states, e.g., asthma, cystic fibrosis, and bronchitis, are characterized by quantitative and qualitative changes in mucus biosynthesis that contribute to pulmonary pathology. Similar alterations in various aspects of mucin biochemistry and biophysics, leading to mucus hypersecretion and altered mucus rheology, result from inhalation of certain air pollutants, such as ozone, sulfur dioxide, nitrogen dioxide, and cigarette smoke. The consequences of these pollutant-induced alterations in mucus biology are discussed in the context of pulmonary pathophysiology and toxicology. PMID:7925190

  5. MUC5B is a major gel-forming, oligomeric mucin from human salivary gland, respiratory tract and endocervix: identification of glycoforms and C-terminal cleavage.

    PubMed Central

    Wickström, C; Davies, J R; Eriksen, G V; Veerman, E C; Carlstedt, I

    1998-01-01

    Mucins from human whole saliva, as well as from respiratory- and cervical-tract secretions, were subjected to density-gradient centrifugation in CsCl/0.5 M guanidinium chloride. A polydisperse population of MUC5B mucins was demonstrated in all samples using anti-peptide antisera (LUM5B-2, LUM5B-3 and LUM5B-4) raised against sequences within the MUC5B mucin. The sequences recognized by the LUM5B-2 and LUM5B-3 antisera are located within the domains flanking the highly glycosylated regions of MUC5B, and reduction increased the reactivity with these antibodies, suggesting that the epitopes are partially shielded and that these regions are folded and stabilized by disulphide bonds. Rate-zonal centrifugation before and after reduction showed MUC5B to be a large oligomeric mucin composed of disulphide-linked subunits. In saliva and respiratory-tract secretions, populations of MUC5B mucins with different charge densities were identified by ion-exchange HPLC, suggesting the presence of MUC5B 'glycoforms'. In trachea, the F2 monoclonal antibody against the sulpho-Lewis C structure reacted preferentially with the later-to-be-eluted populations. An antibody (LUM5B-4) recognizing a sequence in the C-terminal domain of MUC5B identified, after reduction, the mucin subunits as well as smaller fragments, suggesting that some of the MUC5B mucins are cleaved within the C-terminal domain. Immunohistochemistry revealed that MUC5B is produced by cells dispersed throughout the human submandibular and sublingual glands, in the airway submucosal glands as well as the goblet cells, and in the epithelium and glands of the endocervix. The F2 antibody stained a subpopulation of the MUC5B-producing cells in the airway submucosal glands, suggesting that different cells may produce different glycoforms of MUC5B in this tissue. PMID:9729478

  6. Pseudomonas aeruginosa Reduces VX-809 Stimulated F508del-CFTR Chloride Secretion by Airway Epithelial Cells

    PubMed Central

    Stanton, Bruce A.; Coutermarsh, Bonita; Barnaby, Roxanna; Hogan, Deborah

    2015-01-01

    Background P. aeruginosa is an opportunistic pathogen that chronically infects the lungs of 85% of adult patients with Cystic Fibrosis (CF). Previously, we demonstrated that P. aeruginosa reduced wt-CFTR Cl secretion by airway epithelial cells. Recently, a new investigational drug VX-809 has been shown to increase F508del-CFTR Cl secretion in human bronchial epithelial (HBE) cells, and, in combination with VX-770, to increase FEV1 (forced expiratory volume in 1 second) by an average of 3-5% in CF patients homozygous for the F508del-CFTR mutation. We propose that P. aeruginosa infection of CF lungs reduces VX-809 + VX-770- stimulated F508del-CFTR Cl secretion, and thereby reduces the clinical efficacy of VX-809 + VX-770. Methods and Results F508del-CFBE cells and primary cultures of CF-HBE cells (F508del/F508del) were exposed to VX-809 alone or a combination of VX-809 + VX-770 for 48 hours and the effect of P. aeruginosa on F508del-CFTR Cl secretion was measured in Ussing chambers. The effect of VX-809 on F508del-CFTR abundance was measured by cell surface biotinylation and western blot analysis. PAO1, PA14, PAK and 6 clinical isolates of P. aeruginosa (3 mucoid and 3 non-mucoid) significantly reduced drug stimulated F508del-CFTR Cl secretion, and plasma membrane F508del-CFTR. Conclusion The observation that P. aeruginosa reduces VX-809 and VX-809 + VX-770 stimulated F508del CFTR Cl secretion may explain, in part, why VX-809 + VX-770 has modest efficacy in clinical trials. PMID:26018799

  7. Activity of abundant antimicrobials of the human airway.

    PubMed

    Travis, S M; Conway, B A; Zabner, J; Smith, J J; Anderson, N N; Singh, P K; Greenberg, E P; Welsh, M J

    1999-05-01

    Human airways produce several antimicrobial factors; the most abundant are lysozyme and lactoferrin. Despite their likely importance in preventing infection, and their possible key role in the pathogenesis of cystic fibrosis (CF), we know little about their antibacterial activity in the context of the CF airway. We found that abundant airway antimicrobial factors kill common CF pathogens, although Burkholderia was relatively resistant. To study the antibacterial activity, we developed a rapid, sensitive, and quantitative in vitro luminescence assay. Because NaCl concentrations may be elevated in CF airway surface liquid, we tested the effect of salt on antibacterial activity. Activity of individual factors and of airway lavage fluid was inhibited by high ionic strength, and it was particularly sensitive to divalent cations. However, it was not inhibited by nonionic osmolytes and thus did not require hypotonic liquid. The inhibition by ionic strength could be partially compensated by increased concentrations of antibacterial factors, thus there was no one unique salt concentration for inhibition. CF airway secretions also contain abundant mucin and elastase; however, these had no effect on antibacterial activity of lysozyme, lactoferrin, or airway lavage fluids. When studied at low NaCl concentrations, CF and non-CF airway lavage fluids contained similar levels of antibacterial activity. These results suggest approaches toward developing treatments aimed at preventing or reducing airway infections in individuals with CF. PMID:10226057

  8. IL-1ra Secreted by ATP-Induced P2Y2 Negatively Regulates MUC5AC Overproduction via PLCβ3 during Airway Inflammation

    PubMed Central

    Kim, Jiwook; Kim, Bokyoum; Kim, Joowon; Shin, Yusom; Kim, Judeok; Ryu, Siejeong; Yang, Yu-Mi

    2016-01-01

    Mucus secretion is often uncontrolled in many airway inflammatory diseases of humans. Identifying the regulatory pathway(s) of mucus gene expression, mucus overproduction, and hypersecretion is important to alleviate airway inflammation in these diseases. However, the regulatory signaling pathway controlling mucus overproduction has not been fully identified yet. In this study, we report that the ATP/P2Y2 complex secretes many cytokines and chemokines to regulate airway inflammation, among which IL-1 receptor antagonist (IL-1ra) downregulates MUC5AC gene expression via the inhibition of Gαq-induced Ca2+ signaling. IL-1ra inhibited IL-1α protein expression and secretion, and vice versa. Interestingly, ATP/P2Y2-induced IL-1ra and IL-1α secretion were both mediated by PLCβ3. A dominant-negative mutation in the PDZ-binding domain of PLCβ3 inhibited ATP/P2Y2-induced IL-1ra and IL-1α secretion. IL-1α in the presence of the ATP/P2Y2 complex activated the ERK1/2 pathway in a greater degree and for a longer duration than the ATP/P2Y2 complex itself, which was dramatically inhibited by IL-1ra. These findings suggest that secreted IL-1ra exhibits a regulatory effect on ATP/P2Y2-induced MUC5AC gene expression, through inhibition of IL-1α secretion, to maintain the mucus homeostasis in the airway. Therefore, IL-1ra could be an excellent modality for regulating inflamed airway microenvironments in respiratory diseases. PMID:27034593

  9. Capsaicin-induced mucus secretion in rat airways assessed in vivo and non-invasively by magnetic resonance imaging

    PubMed Central

    Karmouty-Quintana, H; Cannet, C; Sugar, R; Fozard, J R; Page, C P; Beckmann, N

    2007-01-01

    Background and purpose: An up-regulation of the sensory neural pathways in the lung has been implicated in asthma and chronic obstructive pulmonary disease (COPD) and is thought to contribute to mucus hypersecretion, an essential feature of both diseases. The aim of this study was to assess non-invasively the acute effects (up to 60 min) of sensory nerve stimulation by capsaicin in the lung, using magnetic resonance imaging (MRI). Experimental approach: Male Brown Norway rats were imaged prior to and 10, 30 and 60 min after intra-tracheal challenge with capsaicin (30 μgkg−1) or vehicle (0.5% ethanol solution). In subsequent studies, pre-treatment with the transient receptor potential vanilloid (TRPV)-1 antagonist, capsazepine; the dual neurokinin (NK) 1 and NK2 receptor antagonist, DNK333 and the mast cell stabilizer, di-sodium cromoglycate (DSCG) was used to modulate the effects of capsaicin. Key results: Diffuse fluid signals were detected by MRI in the lung as early as 10 min after capsaicin, remaining constant 30 and 60 min after treatment. Broncho-alveolar lavage (BAL) fluid analysis performed 60 min after capsaicin revealed increased mucin concentration. Capsazepine (3.5 mgkg−1), DNK333 (10 mgkg−1) but not DSCG (10 mgkg−1) administered prophylactically were able to block the effect of capsaicin in the airways. Conclusions and implications: These observations suggest that the fluid signals detected by MRI after capsaicin administration reflected predominantly the release of mucus following activation of sensory nerves. They point to the opportunity of non-invasively assessing with MRI the influence of neuronal mechanisms in animal models of asthma and COPD. PMID:17351665

  10. Pyocyanin-induced mucin production is associated with redox modification of FOXA2

    PubMed Central

    2013-01-01

    Background The redox-active pyocyanin (PCN) is a toxic, secondary metabolite secreted by the respiratory pathogen Pseudomonas aeruginosa (PA). Previously, we have shown that mouse lungs chronically exposed to PCN develop goblet cell hyperplasia and metaplasia (GCHM) and mucus hypersecretion, fibrosis and emphysema. These pathological features are commonly found in the airways of several chronic lung diseases, including cystic fibrosis (CF), as well as in mouse airways deficient in the forkhead box A2 (FOXA2), a transcriptional repressor of goblet GCHM and mucus biosynthesis. Furthermore, PCN inhibits FOXA2 by activating the pro-GCHM signaling pathways Stat6 and EGFR. However, it is not known whether PCN-generated reactive oxygen (ROS) and nitrogen (RNS) species posttranslationally modify and inactivate FOXA2. Methods We examined the posttranslational modifications of FOXA2 by PCN using specific antibodies against oxidation, nitrosylation, acetylation and ubiquitination. Electrophoretic mobility shift assay (EMSA) was used to examine the ability of modified FOXA2 to bind the promoter of MUC5B mucin gene. In addition, we used quantitative real time PCR, ELISA, immunofluorescence and mouse lung infection to assess whether the loss of FOXA2 function caused GCHM and mucin overexpression. Finally, we examined the restoration of FOXA2 function by the antioxidant glutathione (GSH). Results We found that PCN-generated ROS/RNS caused nitrosylation, acetylation, ubiquitination and degradation of FOXA2. Modified FOXA2 had reduced ability to bind the promoter of the MUC5B gene. The antioxidant GSH alleviated the modification of FOXA2 by PCN, and inhibited the overexpression of MUC5AC and MUC5B mucins. Conclusion These results suggest that PCN-mediated posttranslational modifications of FOXA2 are positively correlated with GCHM and overexpression of airway mucins. Furthermore, antioxidant treatment restores the function of FOXA2 to attenuate GCHM and mucus hypersecretion. PMID

  11. Ocular Surface Membrane-Associated Mucins.

    PubMed

    Ablamowicz, Anna F; Nichols, Jason J

    2016-07-01

    Ocular surface epithelial cells produce and secrete mucins that form a hydrophilic barrier for protection and lubrication of the eye. This barrier, the glycocalyx, is formed by high molecular weight heavily glycosylated membrane-associated mucins (MAMs) that include MUC1, MUC4, and MUC16. These mucins extend into the tear film from the anterior surfaces of the conjunctiva and cornea, and, through interactions with galectin-3, prevent penetrance of pathogens into the eye. Due primarily to the glycosylation of the mucins, the glycocalyx also creates less friction during blinking and enables the tear film to maintain wetting of the eye. The secretory mucins include soluble MUC7 and gel-forming MUC5AC. These mucins, particularly MUC5AC, assist with removal of debris from the tear film and contribute to the hydrophilicity of the tear film. While new methodologies and cell culture models have expanded our understanding of mucin structure and function on the ocular surface, there is still a paucity of studies characterizing the glycosylation of MAMs on a normal ocular surface and a diseased ocular surface. Although studies have shown alterations in mucin production and expression in dry eye diseases, the relationship between changes in mucins and functional consequences is unclear. This review focuses on comparing what is known about MAMs in wet-surfaced epithelia of the body to what has been studied on the eye. PMID:27154035

  12. Airway epithelium interactions with aeroallergens: role of secreted cytokines and chemokines in innate immunity.

    PubMed

    Gandhi, Vivek D; Vliagoftis, Harissios

    2015-01-01

    Airway epithelial cells are the first line of defense against the constituents of the inhaled air, which include allergens, pathogens, pollutants, and toxic compounds. The epithelium not only prevents the penetration of these foreign substances into the interstitium, but also senses their presence and informs the organism's immune system of the impending assault. The epithelium accomplishes the latter through the release of inflammatory cytokines and chemokines that recruit and activate innate immune cells at the site of assault. These epithelial responses aim to eliminate the inhaled foreign substances and minimize their detrimental effects to the organism. Quite frequently, however, the innate immune responses of the epithelium to inhaled substances lead to chronic and high level release of pro-inflammatory mediators that may mediate the lung pathology seen in asthma. The interactions of airway epithelial cells with allergens will be discussed with particular focus on interactions-mediated epithelial release of cytokines and chemokines and their role in the immune response. As pollutants are other major constituents of inhaled air, we will also discuss how pollutants may alter the responses of airway epithelial cells to allergens. PMID:25883597

  13. Airway Epithelium Interactions with Aeroallergens: Role of Secreted Cytokines and Chemokines in Innate Immunity

    PubMed Central

    Gandhi, Vivek D.; Vliagoftis, Harissios

    2015-01-01

    Airway epithelial cells are the first line of defense against the constituents of the inhaled air, which include allergens, pathogens, pollutants, and toxic compounds. The epithelium not only prevents the penetration of these foreign substances into the interstitium, but also senses their presence and informs the organism’s immune system of the impending assault. The epithelium accomplishes the latter through the release of inflammatory cytokines and chemokines that recruit and activate innate immune cells at the site of assault. These epithelial responses aim to eliminate the inhaled foreign substances and minimize their detrimental effects to the organism. Quite frequently, however, the innate immune responses of the epithelium to inhaled substances lead to chronic and high level release of pro-inflammatory mediators that may mediate the lung pathology seen in asthma. The interactions of airway epithelial cells with allergens will be discussed with particular focus on interactions-mediated epithelial release of cytokines and chemokines and their role in the immune response. As pollutants are other major constituents of inhaled air, we will also discuss how pollutants may alter the responses of airway epithelial cells to allergens. PMID:25883597

  14. Abnormal Histone Methylation is Responsible for Increased VEGF165a Secretion from Airway Smooth Muscle Cells in Asthma

    PubMed Central

    Clifford, Rachel L.; John, Alison E.; Brightling, Christopher E.; Knox, Alan J.

    2012-01-01

    Vascular Endothelial Growth Factor (VEGF), a key angiogenic molecule, is aberrantly expressed in several diseases including asthma where it contributes to bronchial vascular remodelling and chronic inflammation. Asthmatic human airway smooth muscle (HASM) cells hypersecrete VEGF but the mechanism is unclear. Here we defined the mechanism in HASM cells from non-asthmatic (NA) and asthmatic (A) patients. We found that asthmatic cells lacked a repression complex at the VEGF promoter which was present in non-asthmatic cells. Recruitment of G9A, trimethylation of histone H3 at lysine 9 (H3K9me3) and a resultant decrease in RNA polymerase II (RNA pol II) at the VEGF promoter was critical to repression of VEGF secretion in non-asthmatic cells. At the asthmatic promoter H3K9me3 was absent due to failed recruitment of G9a; RNA pol II binding, in association with TAF1, was increased, H3K4me3 was present and Sp1 binding was exaggerated and sustained. In contrast DNA methylation and histone acetylation were similar in A and NA cells. This is the first study to show that airway cells in asthma have altered epigenetic regulation of remodelling gene(s). Histone methylation at genes such as VEGF may be an important new therapeutic target. PMID:22689881

  15. T-bet is induced by interferon-γ to mediate chemokine secretion and migration in human airway smooth muscle cells

    PubMed Central

    2011-01-01

    An inappropriate balance between T-helper (Th)1 and Th2 cytokine production underlies inflammatory changes that result in airway disease. Expression of the T-box transcription factor T-bet regulates differentiation of Th cells and production of Th1 cytokines, particularly IFNγ. T-bet-deficient mice develop airway hyperreactivity, undergo airway remodeling, and exhibit defects in IFNγ production while overproducing Th2 cytokines. T-bet is also reduced in the airways of asthmatic patients, suggesting loss of T-bet expression or activity promotes development of inflammatory airway disease. We present novel data demonstrating T-bet expression is induced in human airway smooth muscle cells (ASMC) by IFNγ. This IFNγ-stimulated expression of T-bet is dependent on signaling through JAK2 and signal transducers and activators of transcription 1 (STAT1) and activates T-bet-dependent DNA binding activity. Expression of T-bet stimulates IFNγ-stimulated IFNγ expression, secretion, and promoter activity, while inhibiting IFNγ-stimulated release of chemokines including monocyte chemoattractant protein (MCP)-1/CCL2, regulated on activation normal T-expressed and secreted (RANTES)/CCL5, and eotaxin/CCL11. This is accompanied by changes in expression of the chemokine receptors CCR3 and IL12Rβ2 and TNFα. T-bet expression also reduces chemotactic migration of ASMC in response to serum and PDGF, which contributes to airway hyperplasia. These results are the first to identify T-bet expression and activity in a structural cell of the lung and may provide new insights into therapeutic targets for inflammatory airway disease. PMID:21239533

  16. Characterization of basolateral K+ channels underlying anion secretion in the human airway cell line Calu-3

    PubMed Central

    Cowley, Elizabeth A; Linsdell, Paul

    2002-01-01

    Transepithelial anion secretion in many tissues depends upon the activity of basolateral channels. Using monolayers of the Calu-3 cell line, a human submucosal serous cell model mounted in an Ussing chamber apparatus, we investigated the nature of the K+ channels involved in basal, cAMP- and Ca2+-stimulated anion secretion, as reflected by the transepithelial short circuit current (Isc). The non-specific K+ channel inhibitor Ba2+ inhibited the basal Isc by either 77 or 16 % when applied directly to the basolateral or apical membranes, respectively, indicating that a basolateral K+ conductance is required for maintenance of basal anion secretion. Using the K+ channel blockers clofilium and clotrimazole, we found basal Isc to be sensitive to clofilium, with a small clotrimazole-sensitive component. By stimulating the cAMP and Ca2+ pathways, we determined that cAMP-stimulated anion secretion was almost entirely abolished by clofilium, but insensitive to clotrimazole. In contrast, the Ca2+-stimulated response was sensitive to both clofilium and clotrimazole. Thus, pharmacologically distinct basolateral K+ channels are differentially involved in the control of anion secretion under different conditions. Isolation of the basolateral K+ conductance in permeabilized monolayers revealed a small basal and forskolin-stimulated Isc. Finally, using the reverse transcriptase-polymerase chain reaction, we found that Calu-3 cells express the K+ channel genes KCNN4 and KCNQ1 and the subunits KCNE2 and KCNE3. We conclude that while KCNN4 contributes to Ca2+-activated anion secretion by Calu-3 cells, basal and cAMP-activated secretion are more critically dependent on other K+ channel types, possibly involving one or more class of KCNQ1-containing channel complexes. PMID:11826162

  17. Cigarette smoke and calcium conspire to impair CFTR function in airway epithelia.

    PubMed

    Braun, Andrew P

    2014-01-01

    To maintain health and function in response to inhaled environmental irritants and toxins, the lungs and airways depend upon an innate defense system that involves the secretion of mucus (i.e., mucin, salts, and water) by airway epithelium onto the apical surface to trap foreign particles. Airway mucus is then transported in an oral direction via ciliary beating and coughing, which helps to keep the airways clear. CFTR (cystic fibrosis transmembrane conductance regulator) is a cAMP-regulated Cl(-) channel in the apical membrane of epithelium that contributes to salt and water secretion onto the luminal surface of airways, thereby ensuring that secreted mucus is sufficiently hydrated for movement along the epithelial surface. Dehydration of airway mucus, as occurs in cystic fibrosis, results in a more viscous, less mobile secretion that compromises the lung’s innate defense system by facilitating a build-up of foreign particles and bacterial growth. Related to this situation is chronic obstructive pulmonary disease (COPD), which is a leading cause of death globally. A major cause of COPD is cigarette smoking, which has been reported to decrease the cellular levels of CFTR in airway epithelia. In their recent article, Rasmussen and coworkers now report that exposure to cigarette smoke elevates cytosolic free Ca(2+) in airway epithelium, leading to decreased surface localization and cellular expression of CFTR and reduced levels of secreted airway surface liquid. Blocking this increase in cytosolic Ca(2+) largely prevented CFTR loss in airway epithelium and surprisingly, cellular lysosomes appear to be a major source for smoke-induced Ca(2+) elevation. PMID:24755862

  18. [In vitro evaluation of mucolytic activities of some expectorants using porcine gastric mucin].

    PubMed

    Misawa, M; Imamura, N

    1988-10-01

    The measurement of viscoelasticity of airway secretions (sputum) has been very difficult, because the secretions, mainly consisting of high molecular weight glycoproteins, are heterogeneous and non-Newtonian viscous fluid. In the present study, a new in vitro method was devised for evaluating the effects of mucolytic expectorants, using porcine gastric mucin as a mucous fluid. Twenty percent porcine gastric mucin solution was prepared by dissolving it in tris-HCl buffer solution. The mucolytics tested were incubated with the mucin solution at pH 7.0 and 37 degrees C for 30 min. The viscoelasticity of mucous fluid was determined by the glass plate method and rheometer method. The two cysteine-mucolytics, acetylcysteine (10(-3)-10(-1) M) and ethylcysteine++ (10(-3)-10(-1) M) showed a marked viscoelasticity-lowering effect with either method. On the other hand, another cysteine-mucolytic, carbocysteine had no mucolytic effect at pH 7.0, but showed its effect at pH 6.0. A protease-mucolytic, alpha-chymotrypsin (0.1-10 mg/ml), remarkably lowered the viscoelasticity of mucin fluid with either method. Bromhexine (3 X 10(-4)-3 X 10(-3) M) had no mucolytic effect even at the range of pH 6-8. From the above findings, it is indicated that distinct evaluation of the mucolytic actions of expectorants is feasible using porcine gastric mucin. The glass plate method has many advantages over the rheometer method in terms of required sample volume, measurement time, inexpensive, and so on. PMID:2468589

  19. Link between allergic asthma and airway mucosal infection suggested by proteinase-secreting household fungi.

    PubMed

    Porter, P; Susarla, S C; Polikepahad, S; Qian, Y; Hampton, J; Kiss, A; Vaidya, S; Sur, S; Ongeri, V; Yang, T; Delclos, G L; Abramson, S; Kheradmand, F; Corry, D B

    2009-11-01

    Active fungal proteinases are powerful allergens that induce experimental allergic lung disease strongly resembling atopic asthma, but the precise relationship between proteinases and asthma remains unknown. Here, we analyzed dust collected from the homes of asthmatic children for the presence and sources of active proteinases to further explore the relationship between active proteinases, atopy, and asthma. Active proteinases were present in all houses and many were derived from fungi, especially Aspergillus niger. Proteinase-active dust extracts were alone insufficient to initiate asthma-like disease in mice, but conidia of A. niger readily established a contained airway mucosal infection, allergic lung disease, and atopy to an innocuous bystander antigen. Proteinase produced by A. niger enhanced fungal clearance from lung and was required for robust allergic disease. Interleukin 13 (IL-13) and IL-5 were required for optimal clearance of lung fungal infection and eosinophils showed potent anti-fungal activity in vitro. Thus, asthma and atopy may both represent a protective response against contained airway infection due to ubiquitous proteinase-producing fungi. PMID:19710638

  20. Vasoactive peptides upregulate mRNA expression and secretion of vascular endothelial growth factor in human airway smooth muscle cells.

    PubMed

    Alagappan, Vijay K T; Willems-Widyastuti, Anna; Seynhaeve, Ann L B; Garrelds, Ingrid M; ten Hagen, Timo L M; Saxena, Pramod R; Sharma, Hari S

    2007-01-01

    Airway remodeling and associated angiogenesis are documented features of asthma, of which the molecular mechanisms are not fully understood. Angiotensin (ANG)II and endothelin (ET)-1 are potent vasoconstricting circulatory hormones implicated in asthma. We investigated the effects of ANG II and ET-1 on human airway smooth muscle (ASM) cells proliferation and growth and examined the mRNA expression and release of the angiogenic peptide, vascular endothelial growth factor (VEGF). Serum deprived (48 h) human ASM cells were incubated with ANG II (100 nM) or ET-1 (10 nM) for 30 min, 1, 2, 4, 8, 16, and 24 h and the endogenous synthesis of VEGF was examined in relation to control cells receiving serum free culture medium. ET-1 induced time dependent DNA biosynthesis as determined by [3H]-thymidine incorporation assay. Using northern blot hybridization, we detected two mRNA species of 3.9 and 1.7 kb encoding VEGF in the cultured smooth muscle cells. Both ANG II and ET-1 induced the mRNA expression (two- to threefold) and secretion (1.8- to 2.8-fold) of VEGF reaching maximal levels between 4-8 h of incubation. Induced expression and release of VEGF declined after 8 h of ANG II incubation while levels remained elevated in the case of ET-1. The conditioned medium derived from ET-1-treated ASM cells induced [3H]-thymidine incorporation and cell number in porcine pulmonary artery endothelial as well as human umbilical vein endothelial cells. Moreover, the VEGF tyrosine kinase receptor inhibitor blocked the conditioned medium induced mitogenesis in endothelial cells. Our results suggest a potential role for ANG II and ET-1 in ASM cell growth and upregulation of VEGF that may participate in endothelial cell proliferation via paracrine mechanisms and thus causing pathological angiogenesis and vascular remodelling seen during asthma. PMID:17406064

  1. The chitinase-like protein YKL-40 increases mucin5AC production in human bronchial epithelial cells

    SciTech Connect

    Liu, Chunyi; Li, Qi; Zhou, Xiangdong; Kolosov, Victor P.; Perelman, Juliy M.

    2013-11-01

    Mucus overproduction is an important feature in patients with chronic inflammatory airway diseases. However, the regulatory mechanisms that mediate excessive mucin production remain elusive. Recently, the level of YKL-40, a chitinase-like protein, has been found to be significantly increased in chronic inflammatory airway diseases and has been shown to be associated with the severity of these diseases. In this study, we sought to explore the effect of YKL-40 on mucin5AC (MUC5AC) production in chronic inflammatory airway diseases and the potential signaling pathways involved in this process. We found that elevated YKL-40 levels increased the mRNA and protein expression of MUC5AC in a dose- and time-dependent manner, in association with the phosphorylation of extracellular signal-regulated kinase (ERK) and nuclear factor κB (NF-κB), reflecting their activation. These responses were significantly suppressed by the knockdown of protease-activating receptor 2 (PAR2) with specific small interfering RNA or the inhibitors of ERK and NF-κB. YKL-40-induced MUC5AC overproduction was also effectively attenuated by the inhibitor of focal adhesion kinase (FAK). Taken together, these results imply that YKL-40 can stimulate excessive MUC5AC production through PAR2- and FAK-mediated mechanisms. - Highlights: • MUC5AC is the major secreted mucin in chronic inflammatory airway diseases. • YKL-40 is a prototype of the chitinase-like protein in mammals. • YKL-40 is an active player in chronic inflammatory airway diseases. • YKL-40 can increase MUC5AC production via PAR2-mediated pathway. • FAK is another candidate to mediate YKL-40-induced MUC5AC overexpression.

  2. Oxidant stress stimulates anion secretion from the human airway epithelial cell line calu-3: implications for cystic fibrosis lung disease

    PubMed Central

    Cowley, Elizabeth A; Linsdell, Paul

    2002-01-01

    Exposure to reactive oxygen species (ROS) is associated with tissue damage in the lung and may be a common element in the pathogenesis of all inflammatory lung diseases. Exposure to the ROS hydrogen peroxide (H2O2) evoked a rapid increase in transepithelial anion secretion across monolayers of the human submucosal gland serous cell line Calu-3. This increase was almost entirely abolished by the addition of diphenylamine-2-carboxylate (DPC), implicating the cystic fibrosis transmembrane conductance regulator (CFTR) Cl− channel in the response. The response was also reduced by inhibitors of basolateral K+ channels. Studies of electrically isolated apical and basolateral membranes revealed that H2O2 stimulated both apical Cl− and basolateral K+ conductances (GCl and GK). Apical GCl was sensitive to DPC, but unaffected by 4,4′-diisothiocyanatostilbene-2,2′-disulfonic acid (DIDS), suggesting that CFTR is the major anion conduction pathway mediating the response to H2O2. Additionally, H2O2 had no effect on GCl in the presence of the adenylate cyclase inhibitor SQ22536 or following maximal stimulation of GCl with forskolin, implicating the cAMP-dependent protein kinase pathway in the apical response to H2O2. Basolateral GK was reduced by the K+ channel inhibitors clotrimazole and clofilium, indicating roles for KCNN4 and KCNQ1 in the H2O2-stimulated response. We propose that ROS-stimulated anion secretion from serous cells plays an important role in keeping the airways clear from damaging radicals that could potentially initiate tissue destruction. Our finding that this response is CFTR dependent suggests that an important host defence mechanism would be dysfunctional in the cystic fibrosis (CF) lung. Loss of this compensatory protective mechanism could expose the CF lung to ROS for extended periods, which could be important in the pathogenesis of CF lung disease. PMID:12181292

  3. Oxidant stress stimulates anion secretion from the human airway epithelial cell line Calu-3: implications for cystic fibrosis lung disease.

    PubMed

    Cowley, Elizabeth A; Linsdell, Paul

    2002-08-15

    Exposure to reactive oxygen species (ROS) is associated with tissue damage in the lung and may be a common element in the pathogenesis of all inflammatory lung diseases. Exposure to the ROS hydrogen peroxide (H2O2) evoked a rapid increase in transepithelial anion secretion across monolayers of the human submucosal gland serous cell line Calu-3. This increase was almost entirely abolished by the addition of diphenylamine-2-carboxylate (DPC), implicating the cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel in the response. The response was also reduced by inhibitors of basolateral K+ channels. Studies of electrically isolated apical and basolateral membranes revealed that H2O2 stimulated both apical Cl- and basolateral K+ conductances (G(Cl) and G(K)). Apical G(Cl) was sensitive to DPC, but unaffected by 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), suggesting that CFTR is the major anion conduction pathway mediating the response to H2O2. Additionally, H2O2 had no effect on G(Cl) in the presence of the adenylate cyclase inhibitor SQ22536 or following maximal stimulation of G(Cl) with forskolin, implicating the cAMP-dependent protein kinase pathway in the apical response to H2O2. Basolateral G(K) was reduced by the K+ channel inhibitors clotrimazole and clofilium, indicating roles for KCNN4 and KCNQ1 in the H2O2-stimulated response. We propose that ROS-stimulated anion secretion from serous cells plays an important role in keeping the airways clear from damaging radicals that could potentially initiate tissue destruction. Our finding that this response is CFTR dependent suggests that an important host defence mechanism would be dysfunctional in the cystic fibrosis (CF) lung. Loss of this compensatory protective mechanism could expose the CF lung to ROS for extended periods, which could be important in the pathogenesis of CF lung disease. PMID:12181292

  4. Model of ion transport regulation in chloride-secreting airway epithelial cells. Integrated description of electrical, chemical, and fluorescence measurements.

    PubMed Central

    Hartmann, T; Verkman, A S

    1990-01-01

    An electrokinetic model was developed to calculate the time course of electrical parameters, ion fluxes, and intracellular ion activities for experiments performed in airway epithelial cells. Model variables included cell [Na], [K], [Cl], volume, and membrane potentials. The model contained apical membrane Cl, Na, and K conductances, basolateral membrane K conductance, Na/K/2 Cl and Na/Cl symport, and 3 Na/2 K ATPase, and a paracellular conductance. Transporter permeabilities and ion saturabilities were determined from reported ion flux data and membrane potentials in intact canine trachea. Without additional assumptions, the model predicted accurately the measured short-circuit current (Isc), cellular conductances, voltage-divider ratios, open-circuit potentials, and the time course of cell ion composition in ion substitution experiments. The model was used to examine quantitatively: (a) the effect of transport inhibitors on Isc and membrane potentials, (b) the dual role of apical Cl and basolateral K conductance in cell secretion, (c) whether the basolateral symporter requires K, and (d) the regulation of apical Cl conductance by cAMP and Ca-dependent signaling pathways. Model predictions gave improved understanding of the interrelations among transporting systems and in many cases gave surprising predictions that were not obvious without a detailed model. The model developed here has direct application to secretory or absorptive epithelial cells in the kidney thick ascending limb, cornea, sweat duct, and intestine in normal and pathophysiological states such as cystic fibrosis and cholera. PMID:1698471

  5. Carvedilol binding to β2-adrenergic receptors inhibits CFTR-dependent anion secretion in airway epithelial cells.

    PubMed

    Peitzman, Elizabeth R; Zaidman, Nathan A; Maniak, Peter J; O'Grady, Scott M

    2016-01-01

    Carvedilol functions as a nonselective β-adrenergic receptor (AR)/α1-AR antagonist that is used for treatment of hypertension and heart failure. Carvedilol has been shown to function as an inverse agonist, inhibiting G protein activation while stimulating β-arrestin-dependent signaling and inducing receptor desensitization. In the present study, short-circuit current (Isc) measurements using human airway epithelial cells revealed that, unlike β-AR agonists, which increase Isc, carvedilol decreases basal and 8-(4-chlorophenylthio)adenosine 3',5'-cyclic monophosphate-stimulated current. The decrease in Isc resulted from inhibition of the cystic fibrosis transmembrane conductance regulator (CFTR). The carvedilol effect was abolished by pretreatment with the β2-AR antagonist ICI-118551, but not the β1-AR antagonist atenolol or the α1-AR antagonist prazosin, indicating that its inhibitory effect on Isc was mediated through interactions with apical β2-ARs. However, the carvedilol effect was blocked by pretreatment with the microtubule-disrupting compound nocodazole. Furthermore, immunocytochemistry experiments and measurements of apical CFTR expression by Western blot analysis of biotinylated membranes revealed a decrease in the level of CFTR protein in monolayers treated with carvedilol but no significant change in monolayers treated with epinephrine. These results demonstrate that carvedilol binding to apical β2-ARs inhibited CFTR current and transepithelial anion secretion by a mechanism involving a decrease in channel expression in the apical membrane. PMID:26566905

  6. Characterization of the human mucin gene MUC5AC: a consensus cysteine-rich domain for 11p15 mucin genes?

    PubMed Central

    Guyonnet Duperat, V; Audie, J P; Debailleul, V; Laine, A; Buisine, M P; Galiegue-Zouitina, S; Pigny, P; Degand, P; Aubert, J P; Porchet, N

    1995-01-01

    To date five human mucin cDNAs (MUC2, 5A, 5B, 5C and 6) mapped to 11p15.3-15.5, so it appears that this chromosome region might contain several distinct gene loci for mucins. Three of these cDNAs, MUC5A, B and C, were cloned in our laboratory and previously published. A common number, 5, was recommended by the Human Gene Mapping Nomenclature Committee to designate them because of their common provenance from human tracheobronchial mucosa. In order to define whether they are products of the same gene locus or distinct loci, we describe in this paper physical mapping of these cDNAs using the strategy of analysis of CpG islands by pulse-field gel electrophoresis. The data suggest that MUC5A and MUC5C are part of the same gene (called MUC5AC) which is distinct from MUC5B. In the second part of this work, complete sequences of the inserts corresponding to previously described (JER47, JER58) and novel (JER62, JUL32, MAR2, MAR10 and MAR11) cDNAs of the so-called MUC5AC gene are presented and analysed. The data show that in this mucin gene, the tandem repeat domain is interrupted several times with a subdomain encoding a 130 amino acid cysteine-rich peptide in which the TR3A and TR3B peptides previously isolated by Rose et al. [Rose, Kaufman and Martin (1989) J. Biol. Chem., 264, 8193-8199] from airway mucins are found. A consensus peptide sequence for these subdomains involving invariant positions of most of the cysteines is proposed. The consensus nucleotide sequence of this subdomain is also found in the MUC2 gene and in the MUC5B gene, two other mucin genes mapped to 11p15. The functional significance for secreted mucins of these cysteine-rich subdomains and the modular organization of mucin peptides are discussed. Images Figure 3 Figure 4 Figure 5 Figure 8 PMID:7826332

  7. Basolateral chloride loading by the anion exchanger type 2: role in fluid secretion by the human airway epithelial cell line Calu-3

    PubMed Central

    Huang, Junwei; Shan, Jiajie; Kim, Dusik; Liao, Jie; Evagelidis, Alexandra; Alper, Seth L; Hanrahan, John W

    2012-01-01

    Anion exchanger type 2 (AE2 or SLC4A2) is an electroneutral Cl−/HCO3− exchanger expressed at the basolateral membrane of many epithelia. It is thought to participate in fluid secretion by airway epithelia. However, the role of AE2 in fluid secretion remains uncertain, due to the lack of specific pharmacological inhibitors, and because it is electrically silent and therefore does not contribute directly to short-circuit current (Isc). We have studied the role of AE2 in Cl− and fluid secretion by the airway epithelial cell line Calu-3. After confirming expression of its mRNA and protein, a knock-down cell line called AE2-KD was generated by lentivirus-mediated RNA interference in which AE2 mRNA and protein levels were reduced ≥90%. Suppressing AE2 increased the expression of the cystic fibrosis transmembrane conductance regulator (CFTR) by ∼70% without affecting the levels of NKCC1 (Na+–K+–2Cl− cotransporter) or NBCe1 (Na+–nHCO3− cotransporter). cAMP agonists stimulated fluid secretion by parental Calu-3 and scrambled shRNA cells >6.5-fold. In AE2-KD cells this response was reduced by ∼70%, and the secreted fluid exhibited elevated pH and [HCO3−] as compared with the control lines. Unstimulated equivalent short-circuit current (Ieq) was elevated in AE2-KD cells, but the incremental response to forskolin was unaffected. The modest bumetanide-induced reductions in both Ieq and fluid secretion were more pronounced in AE2-KD cells. Basolateral Cl−/HCO3− exchange measured by basolateral pH-stat in cells with permeabilized apical membranes was abolished in AE2-KD monolayers, and the intracellular alkalinization resulting from basolateral Cl− removal was reduced by ∼80% in AE2-KD cells. These results identify AE2 as a major pathway for basolateral Cl− loading during cAMP-stimulated secretion of Cl− and fluid by Calu-3 cells, and help explain the large bumetanide-insensitive component of fluid secretion reported previously in airway

  8. Postentry Processing of Recombinant Adeno-Associated Virus Type 1 and Transduction of the Ferret Lung Are Altered by a Factor in Airway Secretions

    PubMed Central

    Yan, Ziying; Sun, Xingshen; Evans, Idil A.; Tyler, Scott R.; Song, Yi; Liu, Xiaoming; Sui, Hongshu

    2013-01-01

    Abstract We recently created a cystic fibrosis ferret model that acquires neonatal lung infection. To develop lung gene therapies for this model, we evaluated recombinant adeno-associated virus (rAAV)-mediated gene transfer to the neonatal ferret lung. Unlike in vitro ferret airway epithelial (FAE) cells, in vivo infection of the ferret lung with rAAV1 required proteasome inhibitors to achieve efficient airway transduction. We hypothesized that differences in transduction between these two systems were because of an in vivo secreted factor that alter the transduction biology of rAAV1. Indeed, treatment of rAAV1 with ferret airway secretory fluid (ASF) strongly inhibited rAAV1, but not rAAV2, transduction of primary FAE and HeLa cells. Properties of the ASF inhibitory factor included a strong affinity for the AAV1 capsid, heat-stability, negative charge, and sensitivity to endoproteinase Glu-C. ASF-treated rAAV1 dramatically inhibited apical transduction of FAE ALI cultures (512-fold), while only reducing viral entry by 55-fold, suggesting that postentry processing of virus was influenced by the inhibitor factor. Proteasome inhibitors rescued transduction in the presence of ASF (∼1600-fold) without effecting virus internalization, while proteasome inhibitors only enhanced transduction 45-fold in the absence of ASF. These findings demonstrate that a factor in lung secretions can influence intracellular processing of rAAV1 in a proteasome-dependent fashion. PMID:23948055

  9. Nucleotide-mediated airway clearance.

    PubMed

    Schmid, Andreas; Clunes, Lucy A; Salathe, Mathias; Verdugo, Pedro; Dietl, Paul; Davis, C William; Tarran, Robert

    2011-01-01

    A thin layer of airway surface liquid (ASL) lines the entire surface of the lung and is the first point of contact between the lung and the environment. Surfactants contained within this layer are secreted in the alveolar region and are required to maintain a low surface tension and to prevent alveolar collapse. Mucins are secreted into the ASL throughout the respiratory tract and serve to intercept inhaled pathogens, allergens and toxins. Their removal by mucociliary clearance (MCC) is facilitated by cilia beating and hydration of the ASL by active ion transport. Throughout the lung, secretion, ion transport and cilia beating are under purinergic control. Pulmonary epithelia release ATP into the ASL which acts in an autocrine fashion on P2Y(2) (ATP) receptors. The enzymatic network describes in Chap. 2 then mounts a secondary wave of signaling by surface conversion of ATP into adenosine (ADO), which induces A(2B) (ADO) receptor-mediated responses. This chapter offers a comprehensive description of MCC and the extensive ramifications of the purinergic signaling network on pulmonary surfaces. PMID:21560046

  10. Annexin II mediates the neutrophil elastase-stimulated exocytosis of mucin 5ac.

    PubMed

    Xu, Rui; Li, Qi; Zhou, Xiangdong; Perelman, Juliy M; Kolosov, Victor P

    2014-01-01

    The overexpression and hypersecretion of mucus is a hallmark of several chronic pulmonary inflammatory diseases, including chronic obstructive pulmonary disease (COPD), asthma and cystic fibrosis. Mucin 5ac (MUC5AC) is a major component of airway mucus. Annexin II (ANXII) has been reported to be expressed in various cells and is associated with the fusion of secretory vesicles. Neutrophil elastase (NE) is present at high concentrations in the airway surface fluid in patients with cystic fibrosis and various other severe diseases. However, the role of ANXII in NE-induced secretion of MUC5AC granules remains unclear. It was determined that NE upregulates the transcription and protein synthesis of ANXII in 16HBE human bronchial epithelial cells. Following stimulation with NE, ANXII is recruited to the cell membrane, as visualised by cell immunochemistry and laser confocal microscopy, and the redistribution of ANXII is inhibited by the protein kinase-C (PKC) inhibitor bisindolylmaleimide I. Conversely, depleting endogenous ANXII decreases MUC5AC secretion into the cell culture supernatant and increases the levels of intracellular MUC5AC protein. The data indicated that ANXII is associated with the secretion of MUC5AC granules. PMID:24247640

  11. 2-O, 3-O-Desulfated Heparin Inhibits Neutrophil Elastase–Induced HMGB-1 Secretion and Airway Inflammation

    PubMed Central

    Griffin, Kathryn L.; Fischer, Bernard M.; Kummarapurugu, Apparao B.; Zheng, Shuo; Kennedy, Thomas P.; Rao, Narayanam V.; Foster, W. Michael

    2014-01-01

    Neutrophil elastase (NE) is a major inflammatory mediator in cystic fibrosis (CF) that is a robust predictor of lung disease progression. NE directly causes airway injury via protease activity, and propagates persistent neutrophilic inflammation by up-regulation of neutrophil chemokine expression. Despite its key role in the pathogenesis of CF lung disease, there are currently no effective antiprotease therapies available to patients with CF. Although heparin is an effective antiprotease and anti-inflammatory agent, its anticoagulant activity prohibits its use in CF, due to risk of pulmonary hemorrhage. In this report, we demonstrate the efficacy of a 2-O, 3-O-desulfated heparin (ODSH), a modified heparin with minimal anticoagulant activity, to inhibit NE activity and to block NE-induced airway inflammation. Using an established murine model of intratracheal NE-induced airway inflammation, we tested the efficacy of intratracheal ODSH to block NE-generated neutrophil chemoattractants and NE-triggered airway neutrophilic inflammation. ODSH inhibited NE-induced keratinocyte-derived chemoattractant and high-mobility group box 1 release in bronchoalveolar lavage. ODSH also blocked NE-stimulated high-mobility group box 1 release from murine macrophages in vitro, and inhibited NE activity in functional assays consistent with prior reports of antiprotease activity. In summary, this report suggests that ODSH is a promising antiprotease and anti-inflammatory agent that may be useful as an airway therapy in CF. PMID:24325600

  12. Airway Hydration, Apical K(+) Secretion, and the Large-Conductance, Ca(2+)-activated and Voltage-dependent Potassium (BK) Channel.

    PubMed

    Kis, Adrian; Krick, Stefanie; Baumlin, Nathalie; Salathe, Matthias

    2016-04-01

    Large-conductance, calcium-activated, and voltage-gated K(+) (BK) channels are expressed in many tissues of the human body, where they play important roles in signaling not only in excitable but also in nonexcitable cells. Because BK channel properties are rendered in part by their association with four β and four γ subunits, their channel function can differ drastically, depending on in which cellular system they are expressed. Recent studies verify the importance of apically expressed BK channels for airway surface liquid homeostasis and therefore of their significant role in mucociliary clearance. Here, we review evidence that inflammatory cytokines, which contribute to airway diseases, can lead to reduced BK activity via a functional down-regulation of the γ regulatory subunit LRRC26. Therefore, manipulation of LRRC26 and pharmacological opening of BK channels represent two novel concepts of targeting epithelial dysfunction in inflammatory airway diseases. PMID:27115952

  13. Physical Properties of the Glycoprotein Mucin

    NASA Astrophysics Data System (ADS)

    Matthews, Garrett; Davis, William; Superfine, Richard; Boucher, Richard

    2003-03-01

    Epithelial cell surfaces are covered by a protective gel known as mucus. The physiological function of this gel depends on its rheological properties, and these properties are largely derived from the secreted glycoprotein mucin. The genetic disease Cystic Fibrosis (CF) is characterized by the adhesion of thick, viscous mucus on these tissues. In the lungs, this results in the interruption of mucus transport thus compromising the first line of defense against pathogens in these tissues. In order to restore the flow of tracheobronchial mucus out of the body, knowledge of the molecular and physical properties of mucin and mucin solutions would be greatly beneficial. The present model for these molecules is that of a long linear strand consisting of highly glycosylated regions linked by cystein-rich globular regions. It is thought that the globular regions may interact either through intermolecular disulfide bonds or through hydrophobic interactions. It has also been speculated that the glycosylated regions may have lectin-like interactions. In the present work, single mucin molecules were imaged at high resolution using atomic force microscopy (AFM). Phase mode imaging was used to map the interactions between functionalized AFM tips and the molecular topography. Additionally, using force-distance curves with the AFM, the adhesion between mucin bound tips and cell surface glycocalyx and glycocalyx-like model surfaces, was measured. And, finally, the viscoelastic properties of mucin solutions were measured using the recently developed technique, single particle tracking microrheology. A model is being developed that will incorporate the properties of mucins beginning at the single molecule and ending with the bulk viscoelastic properties.

  14. The physicochemical characterisation of pepsin degraded pig gastric mucin.

    PubMed

    Abodinar, Atiga; Tømmeraas, Kristoffer; Ronander, Elena; Smith, Alan M; Morris, Gordon A

    2016-06-01

    Mucins are the main macromolecular components of the mucus secretions that cover the oral cavity, gastrointestinal and urogenital tracts of animals. The properties of the mucus secretions are therefore directly correlated with the physicochemical properties of mucin glycoproteins. In this study, mucins were obtained from pig gastric mucous after digestion with pepsin at 37°C for 4h, these mucins were characterised in terms of compositional and hydrodynamic properties. Compositional analysis showed that this mucin contains protein (15%), carbohydrates (55%) of which the constituents are: fucose (4%), galactose (9%), glucosamine (55%), glucosamine (33%) and sialic acid (2%). The latter component gives the mucin polymer a pH-dependant negative charge, with a ζ-potential of -3mV at pH 1.2 up to -11mV at pH 7.4. The weight average molar mass was ∼1×10(6)g/mol and intrinsic viscosity was ∼0.42dL/g although there was a small pH dependency due to the polyelectrolyte behavior of the polymer. The measurements of viscosity versus shear rate showed shear thinning behavior and the critical overlap concentration was determined to be 10-11% w/v indicating a compact structure. Knowledge of these properties is fundamental to the understanding interactions of mucins, with for example, novel drug delivery systems. PMID:26944659

  15. [Physiological role of mucins in the colonic barrier integrity].

    PubMed

    Gaudier, Estelle; Hoebler, Christine

    2006-01-01

    Colonic mucus is a key element of colonic barrier as it is located at the frontier between luminal microflora and colonic mucosa itself. Colonic mucus is mainly composed of high molecular weight glycoproteins called mucins that can be either secreted or membrane-linked. The expression of various colonic mucins is altered in colorectal cancers or inflammations. The aim of this review is to highlight the crucial role played by colonic mucins in the maintenance of colonic barrier integrity, both because they are part of the protective mucus layer, and because they individually exert specific functions involved in epithelial barrier, like cell growth and differentiation, immunomodulation, signal transduction or cell adhesion. PMID:17075443

  16. Respiratory mucins: identification of core proteins and glycoforms.

    PubMed

    Thornton, D J; Carlstedt, I; Howard, M; Devine, P L; Price, M R; Sheehan, J K

    1996-06-15

    At least eight mucin apoproteins are expressed by the tracheobronchial epithelium, but it is not known which, if any, of these are major constituents of the respiratory secretions responsible for the formation of the mucus gel. To address this we have isolated mucins from normal, asthmatic and chronic bronchitic secretions. The asthmatic mucin reduced subunits were fractionated into four populations (I-IV) by anion-exchange HPLC. Amino acid and monosaccharide compositional analysis, as well as M(r) and size measurements, indicate that two of these populations (I and II) are glycoforms of the same or related apoprotein(s) and that the other populations contain two different apoproteins. A panel of antibodies and antisera recognizing the variable number tandem repeat (VNTR) of specific mucin apoproteins did not, as predicted, react with the glycosylated molecules, but after deglycosylation the majority of these probes (with the exception of those to MUC2, which were negative) reacted at a low level with each of the subunit populations. In contrast, an antiserum against a non-VNTR sequence of MUC5AC identified one of the populations (III) as the MUC5AC mucin. The MUC5AC reduced subunit had an M(r) of 2.2 x 10(6) and an RG (radius of gyration) of 57 nm. The genetic identities of the major mucin (populations I and II) and a minor component (population IV) were not established. The MUC5AC mucin was also identified as a major component in the pooled normal secretions from 20 individuals, whereas in a chronic bronchitic sample it was only a minor constituent. Furthermore, in all these different respiratory secretions the MUC5AC mucin appears as a similar biochemical entity, as assessed by Mono Q chromatography and agarose electrophoresis, suggesting that it may have a well-defined pattern of glycosylation in the respiratory tract. PMID:8670177

  17. Macrolides Inhibit Fusobacterium nucleatum-Induced MUC5AC Production in Human Airway Epithelial Cells

    PubMed Central

    Nagaoka, Kentaro; Harada, Yosuke; Yamada, Koichi; Migiyama, Yohei; Morinaga, Yoshitomo; Hasegawa, Hiroo; Izumikawa, Koichi; Kakeya, Hiroshi; Nishimura, Masaharu; Kohno, Shigeru

    2013-01-01

    Fusobacterium nucleatum is one of the most common anaerobic bacteria in periodontitis and is responsible for several extraoral infections, including respiratory tract diseases. In this study, we examined whether F. nucleatum induces mucin secretion in airway epithelial cells. We also examined the effects of macrolides on F. nucleatum-induced mucus production compared with the effects of other antibiotics that exert anti-anaerobic activities. The production of MUC5AC, the major core protein of mucin secreted from the airway surface epithelium, in bronchial epithelial cells after stimulation with culture supernatants (Sup) of F. nucleatum was analyzed by performing enzyme-linked immunosorbent assay and quantitative RT-PCR. The cell-signaling pathway of F. nucleatum Sup stimulation was also analyzed by Western blotting. For inhibition studies, cells were treated with azithromycin, clarithromycin, clindamycin (CLDM), and metronidazole (MTZ). The F. nucleatum Sup induced NCI-H292 cells to express MUC5AC at both the protein level and the mRNA level in both a time- and dose-dependent manner. Macrolides inhibited F. nucleatum Sup-induced MUC5AC production, while CLDM and MTZ were less effective. F. nucleatum Sup induced the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2), and this induction was suppressed by macrolides. F. nucleatum Sup-induced MUC5AC production was blocked by the ERK pathway inhibitor U0126. F. nucleatum is likely to contribute to excessive mucin production, which suggests that periodontitis may correlate with the pathogenesis of chronic respiratory tract infection. Macrolides seem to reduce this mucin production and might represent an additional means of therapeutic intervention for F. nucleatum respiratory tract infections other than CLDM and MTZ. PMID:23380724

  18. Divergent Mechanisms of Interaction of Helicobacter pylori and Campylobacter jejuni with Mucus and Mucins

    PubMed Central

    Naughton, Julie Ann; Mariño, Karina; Dolan, Brendan; Reid, Colm; Gough, Ronan; Gallagher, Mary E.; Kilcoyne, Michelle; Gerlach, Jared Q.; Joshi, Lokesh; Rudd, Pauline; Carrington, Stephen; Bourke, Billy

    2013-01-01

    Helicobacter pylori and Campylobacter jejuni colonize the stomach and intestinal mucus, respectively. Using a combination of mucus-secreting cells, purified mucins, and a novel mucin microarray platform, we examined the interactions of these two organisms with mucus and mucins. H. pylori and C. jejuni bound to distinctly different mucins. C. jejuni displayed a striking tropism for chicken gastrointestinal mucins compared to mucins from other animals and preferentially bound mucins from specific avian intestinal sites (in order of descending preference: the large intestine, proximal small intestine, and cecum). H. pylori bound to a number of animal mucins, including porcine stomach mucin, but with less avidity than that of C. jejuni for chicken mucin. The strengths of interaction of various wild-type strains of H. pylori with different animal mucins were comparable, even though they did not all express the same adhesins. The production of mucus by HT29-MTX-E12 cells promoted higher levels of infection by C. jejuni and H. pylori than those for the non-mucus-producing parental cell lines. Both C. jejuni and H. pylori bound to HT29-MTX-E12 mucus, and while both organisms bound to glycosylated epitopes in the glycolipid fraction of the mucus, only C. jejuni bound to purified mucin. This study highlights the role of mucus in promoting bacterial infection and emphasizes the potential for even closely related bacteria to interact with mucus in different ways to establish successful infections. PMID:23716616

  19. Suppression of type 2 immunity and allergic airway inflammation by secreted products of the helminth Heligmosomoides polygyrus

    PubMed Central

    McSorley, Henry J; O'Gorman, Mary T; Blair, Natalie; Sutherland, Tara E; Filbey, Kara J; Maizels, Rick M

    2016-01-01

    Summary Allergic asthma is less prevalent in countries with parasitic helminth infections, and mice infected with parasites such as Heligmosomoides polygyrus are protected from allergic airway inflammation. To establish whether suppression of allergy could be mediated by soluble products of this helminth, we tested H. polygyrus excretory-secretory (HES) material for its ability to impair allergic inflammation. When HES was added to sensitising doses of ovalbumin, the subsequent allergic airway response was suppressed, with ablated cell infiltration, a lower ratio of effector (CD4+CD25+Foxp3−) to regulatory (CD4+Foxp3+) T (Treg) cells, and reduced Th1, Th2 and Th17 cytokine production. HES exposure reduced IL-5 responses and eosinophilia, abolished IgE production, and inhibited the type 2 innate molecules arginase-1 and RELM-α. Although HES contains a TGF-β-like activity, similar effects in modulating allergy were not observed when administering mammalian TGF-β alone. HES also protected previously sensitised mice, suppressing recruitment of eosinophils to the airways when given at challenge, but no change in Th or Treg cell populations was apparent. Because heat-treatment of HES did not impair suppression at sensitisation, but compromised its ability to suppress at challenge, we propose that HES contains distinct heat-stable and heat-labile immunomodulatory molecules which modulate pro-allergic adaptive and innate cell populations. PMID:22706967

  20. Muc5b is required for airway defence

    NASA Astrophysics Data System (ADS)

    Roy, Michelle G.; Livraghi-Butrico, Alessandra; Fletcher, Ashley A.; McElwee, Melissa M.; Evans, Scott E.; Boerner, Ryan M.; Alexander, Samantha N.; Bellinghausen, Lindsey K.; Song, Alfred S.; Petrova, Youlia M.; Tuvim, Michael J.; Adachi, Roberto; Romo, Irlanda; Bordt, Andrea S.; Bowden, M. Gabriela; Sisson, Joseph H.; Woodruff, Prescott G.; Thornton, David J.; Rousseau, Karine; de La Garza, Maria M.; Moghaddam, Seyed J.; Karmouty-Quintana, Harry; Blackburn, Michael R.; Drouin, Scott M.; Davis, C. William; Terrell, Kristy A.; Grubb, Barbara R.; O'Neal, Wanda K.; Flores, Sonia C.; Cota-Gomez, Adela; Lozupone, Catherine A.; Donnelly, Jody M.; Watson, Alan M.; Hennessy, Corinne E.; Keith, Rebecca C.; Yang, Ivana V.; Barthel, Lea; Henson, Peter M.; Janssen, William J.; Schwartz, David A.; Boucher, Richard C.; Dickey, Burton F.; Evans, Christopher M.

    2014-01-01

    Respiratory surfaces are exposed to billions of particulates and pathogens daily. A protective mucus barrier traps and eliminates them through mucociliary clearance (MCC). However, excessive mucus contributes to transient respiratory infections and to the pathogenesis of numerous respiratory diseases. MUC5AC and MUC5B are evolutionarily conserved genes that encode structurally related mucin glycoproteins, the principal macromolecules in airway mucus. Genetic variants are linked to diverse lung diseases, but specific roles for MUC5AC and MUC5B in MCC, and the lasting effects of their inhibition, are unknown. Here we show that mouse Muc5b (but not Muc5ac) is required for MCC, for controlling infections in the airways and middle ear, and for maintaining immune homeostasis in mouse lungs, whereas Muc5ac is dispensable. Muc5b deficiency caused materials to accumulate in upper and lower airways. This defect led to chronic infection by multiple bacterial species, including Staphylococcus aureus, and to inflammation that failed to resolve normally. Apoptotic macrophages accumulated, phagocytosis was impaired, and interleukin-23 (IL-23) production was reduced in Muc5b-/- mice. By contrast, in mice that transgenically overexpress Muc5b, macrophage functions improved. Existing dogma defines mucous phenotypes in asthma and chronic obstructive pulmonary disease (COPD) as driven by increased MUC5AC, with MUC5B levels either unaffected or increased in expectorated sputum. However, in many patients, MUC5B production at airway surfaces decreases by as much as 90%. By distinguishing a specific role for Muc5b in MCC, and by determining its impact on bacterial infections and inflammation in mice, our results provide a refined framework for designing targeted therapies to control mucin secretion and restore MCC.

  1. Muc5b Is Required for Airway Defense

    PubMed Central

    Roy, Michelle G.; Livraghi-Butrico, Alessandra; Fletcher, Ashley A.; McElwee, Melissa M.; Evans, Scott E.; Boerner, Ryan M.; Alexander, Samantha N.; Bellinghausen, Lindsey K.; Song, Alfred S.; Petrova, Youlia M.; Tuvim, Michael J.; Adachi, Roberto; Romo, Irlanda; Bordt, Andrea S.; Gabriela Bowden, M.; Sisson, Joseph H.; Woodruff, Prescott G.; Thornton, David J.; Rousseau, Karine; De la Garza, Maria M.; Moghaddam, Seyed J.; Karmouty-Quintana, Harry; Blackburn, Michael R.; Drouin, Scott M.; William Davis, C.; Terrell, Kristy A.; Grubb, Barbara R.; O’Neal, Wanda K.; Flores, Sonia C.; Cota-Gomez, Adela; Lozupone, Catherine A.; Donnelly, Jody M.; Watson, Alan M.; Hennessy, Corinne E.; Keith, Rebecca C.; Yang, Ivana V.; Barthel, Lea; Henson, Peter M.; Janssen, William J.; Schwartz, David A.; Boucher, Richard C.; Dickey, Burton F.; Evans, Christopher M.

    2014-01-01

    Respiratory surfaces are exposed to billions of particulates and pathogens daily. A protective mucus barrier traps and eliminates them via mucociliary clearance (MCC)1,2. However, excessive mucus contributes to transient respiratory infections and to the pathogenesis of numerous respiratory diseases1. MUC5AC and MUC5B are evolutionarily conserved genes that encode structurally related mucin glycoproteins, the principal macromolecules in airway mucus1,3. Genetic variants are linked to diverse lung diseases4-6, but specific roles for MUC5AC and MUC5B in MCC, and the lasting effects of their inhibition, are unknown. Here we show that Muc5b (but not Muc5ac) is required for MCC, for controlling infections in the airways and middle ear, and for maintaining immune homeostasis in the lungs. Muc5b deficiency caused materials to accumulate in upper and lower airways. This defect led to chronic infection by multiple bacterial species, including Staphylococcus aureus, and to inflammation that failed to resolve normally7. Apoptotic macrophages accumulated, phagocytosis was impaired, and IL-23 production was reduced inMuc5b−/− mice. By contrast, in Muc5b transgenic (Tg) mice, macrophage functions improved. Existing dogma defines mucous phenotypes in asthma and chronic obstructive pulmonary disease (COPD) as driven by increased MUC5AC, with MUC5B levels either unaffected or increased in expectorated sputum1,8. However, in many patients, MUC5B production at airway surfaces decreases by as much as 90%9-11. By distinguishing a specific role for Muc5b in MCC, and by determining its impact on bacterial infections and inflammation in mice, our results provide a refined framework for designing targeted therapies to control mucin secretion and restore MCC. PMID:24317696

  2. Primary Retroperitoneal Mucinous Cystadenoma

    PubMed Central

    Han, Weon Cheol

    2016-01-01

    Mucinous cystadenomas and cystadenocarcinomas of the ovary are clinically and histopathologically well-established common tumors. However, primary retroperitoneal mucinous cystic tumors are extremely rare, and although their histopathogenesis is still uncertain, several theories have been proposed. Most authors suggest that they develop through mucinous metaplasia in a preexisting mesothelium-lined cyst. An accurate preoperative diagnosis of these tumors is difficult because no effective diagnostic measures have been established. Delay in diagnosis and treatment of this tumor may be fatal for the patient because of complications such as rupture, infection, and malignant transformation. We describe the case of a 31-year-old woman with abdominal pain and a palpable mass. Computed tomography of the abdomen revealed a retroperitoneal cystic mass, which was resected successfully through laparoscopy. Histopathological examination of the resected mass confirmed the diagnosis of a primary retroperitoneal mucinous cystadenoma. The patient was discharged on postoperative day 5 without any complications. PMID:26962534

  3. Cysteamine and prostaglandin F2 beta stimulate rat gastric mucin release

    SciTech Connect

    Lamont, J.T.; Ventola, A.S.; Maull, E.A.; Szabo, S.

    1983-02-01

    Gastric mucin glycoproteins form an adherent gel over the surface epithelium that is thought to protect the stomach against chemical and physical damage. The purpose of this study was to measure the release of mucin glycoproteins from rat stomach after treatment with cysteamine and prostaglandin F2 beta, two structurally unrelated drugs that have been shown to protect the stomach against the noxious effects of alcohol and other damaging agents. Gastric mucin was separated into soluble (washout) and insoluble (adherent) phases before colorimetric quantitation of total mucin, protein-bound hexose, and sialic acid. Cysteamine produced a dose-dependent increase in release of soluble and gel mucin. Prostaglandin F2 beta caused a dose-dependent release of hexose-containing mucin but had no effect on sialic acid-containing glycoproteins. Sepharose 4B chromatography of both the soluble and adherent mucus revealed that greater than 90% was a high molecular weight glycoprotein fraction. N-Ethylmaleimide, a known inhibitor of cytoprotection by cysteamine, had no effect on mucin secretion. Similarly, indomethacin inhibited mucin secretion by cysteamine but did not significantly influence cytoprotection. Thus the secretion of mucin by cytoprotective agents is unlikely by itself to explain the ability of the stomach to resist chemical or physical damage.

  4. Reduced mucociliary clearance in old mice is associated with a decrease in Muc5b mucin.

    PubMed

    Grubb, Barbara R; Livraghi-Butrico, Alessandra; Rogers, Troy D; Yin, Weining; Button, Brian; Ostrowski, Lawrence E

    2016-05-01

    Respiratory infections are a major cause of morbidity and mortality in the elderly. Previous reports have suggested that mucociliary clearance (MCC) is impaired in older individuals, but the cause is unclear. To unravel the mechanisms responsible for the age-associated decline in MCC, we investigated the MCC system in young (3 mo) and old (2 yr) C57BL/6 mice. We found that old mice had significantly reduced MCC function in both the upper and lower airways compared with young mice. Measurement of bioelectric properties of isolated tracheal and bronchial tissue revealed a significant decrease in Cl(-) secretion, suggesting that the older mice may have a reduced ability to maintain a sufficiently hydrated airway surface for efficient MCC. Ciliary beat frequency was also observed to be reduced in the older animals; however, this reduction was small relative to the reduction in MCC. Interestingly, the level of the major secreted mucin, Muc5b, was found to be reduced in both bronchioalveolar lavage and isolated tracheal tissue. Our previous studies of Muc5b(-/-) mice have demonstrated that Muc5b is essential for normal MCC in the mouse. Furthermore, examination of Muc5b(+/-) and wild-type animals revealed that heterozygous animals, which secrete ∼50% of the wild-type level of Muc5b, also demonstrate a markedly reduced level of MCC, confirming the importance of Muc5b levels to MCC. These results demonstrate that aged mice exhibit a decrease in MCC and suggest that a reduced level of secretion of both Cl(-) and Muc5b may be responsible. PMID:26968767

  5. Vitamin A Deficiency Impairs Mucin Expression and Suppresses the Mucosal Immune Function of the Respiratory Tract in Chicks.

    PubMed

    Fan, Xiaoxiao; Liu, Shaoqiong; Liu, Guanhua; Zhao, Jingpeng; Jiao, Hongchao; Wang, Xiaojuan; Song, Zhigang; Lin, Hai

    2015-01-01

    The chicken immune system is immature at the time of hatching. The development of the respiratory immune system after hatching is vital to young chicks. The aim of this study was to investigate the effect of dietary vitamin A supplement levels on respiratory mucin and IgA production in chicks. In this study, 120 one-day-old broiler chicks were randomly divided into 4 groups consisting of three replicates of 10 broilers and subjected to dietary vitamin A supplement levels of 0, 1,500, 6,000, or 12,000 IU/kg for seven days. Compared with control birds, vitamin A supplementation significantly increased the mucin and IgA levels in the bronchoalveolar lavage fluid (BALF) as well as the IgA level in serum. In the lungs, vitamin A supplementation downregulated TNF-α and EGFR mRNA expression. The TGF-β and MUC5AC mRNA expression levels were upregulated by vitamin A supplementation at a dose of 6,000 IU/kg, and the IL-13 mRNA expression level was increased at the 12,000 IU/kg supplement level. Vitamin A deficiency (control) significantly decreased the mRNA expression levels of MUC2, IgA, EGFR, IL-13 and TGF-β in trachea tissue. Histological section analysis revealed that the number of goblet cells in the tracheal epithelium was less in the 0 and 12,000 IU/kg vitamin A supplement groups than in the other groups. In conclusion, vitamin A deficiency suppressed the immunity of the airway by decreasing the IgA and mucin concentrations in neonatal chicks. This study suggested that a suitable level of vitamin A is essential for the secretion of IgA and mucin in the respiratory tract by regulating the gene expression of cytokines and epithelial growth factors. PMID:26422233

  6. Vitamin A Deficiency Impairs Mucin Expression and Suppresses the Mucosal Immune Function of the Respiratory Tract in Chicks

    PubMed Central

    Liu, Guanhua; Zhao, Jingpeng; Jiao, Hongchao; Wang, Xiaojuan; Song, Zhigang; Lin, Hai

    2015-01-01

    The chicken immune system is immature at the time of hatching. The development of the respiratory immune system after hatching is vital to young chicks. The aim of this study was to investigate the effect of dietary vitamin A supplement levels on respiratory mucin and IgA production in chicks. In this study, 120 one-day-old broiler chicks were randomly divided into 4 groups consisting of three replicates of 10 broilers and subjected to dietary vitamin A supplement levels of 0, 1,500, 6,000, or 12,000 IU/kg for seven days. Compared with control birds, vitamin A supplementation significantly increased the mucin and IgA levels in the bronchoalveolar lavage fluid (BALF) as well as the IgA level in serum. In the lungs, vitamin A supplementation downregulated TNF-α and EGFR mRNA expression. The TGF-β and MUC5AC mRNA expression levels were upregulated by vitamin A supplementation at a dose of 6,000 IU/kg, and the IL-13 mRNA expression level was increased at the 12,000 IU/kg supplement level. Vitamin A deficiency (control) significantly decreased the mRNA expression levels of MUC2, IgA, EGFR, IL-13 and TGF-β in trachea tissue. Histological section analysis revealed that the number of goblet cells in the tracheal epithelium was less in the 0 and 12,000 IU/kg vitamin A supplement groups than in the other groups. In conclusion, vitamin A deficiency suppressed the immunity of the airway by decreasing the IgA and mucin concentrations in neonatal chicks. This study suggested that a suitable level of vitamin A is essential for the secretion of IgA and mucin in the respiratory tract by regulating the gene expression of cytokines and epithelial growth factors. PMID:26422233

  7. Physical characterization and profiling of airway epithelial derived exosomes using light scattering.

    PubMed

    Kesimer, Mehmet; Gupta, Richa

    2015-10-01

    Exosomes and other extracellular vesicles have been gaining interest during the last decade due to their emerging role in biology and, disease pathogenesis and their biomarker potential. Almost all published research related to exosomes and other extracellular vesicles include some form of physical characterization. Therefore, these vesicles should be precisely profiled and characterized physically before studying their biological role as intercellular messengers, biomarkers or therapeutic tools. Using a combination of light scattering techniques, including dynamic light scattering (DLS) and multi-angle laser light scattering combined with size exclusion separation (SEC-MALLS), we physically characterized and compared distinct extracellular vesicles derived from the apical secretions of two different cultured airway epithelial cells. The results indicated that epithelial cells release vesicles with distinct physical properties and sizes. Human primary tracheobronchial cell culture (HTBE) derived vesicles have a hydrodynamic radius (Rh) of approximately 340 nm while their radius of gyration (Rg) is approximately 200 nm. Electron microscopy analysis, however, revealed that their spherical component is 40-100 nm in size, and they carry filamentous, entangled membrane mucins on their surface that increases their overall radius. The mucin decoration on the surface defines their size and charge as measured using light scattering techniques. Their surface properties mirror the properties of the cells from which they are derived. This may provide a unique tool for researchers to elucidate the unanswered questions in normal airway biology and innate and adaptive defense, including the remodeling of airways during inflammation, tumorigenesis and metastasis. PMID:25823850

  8. Mucin function in inflammatory bowel disease: an update.

    PubMed

    Boltin, Doron; Perets, Tsachi T; Vilkin, Alex; Niv, Yaron

    2013-02-01

    MUC2 is the primary component of the mucin barrier that separates the intestinal microbiota and the intestinal epithelium. This mucous barrier is affected by both luminal/microbial factors and host/immune factors, both of which have genetic and environmental determinants. The complex interactions between these players in health and disease states are not fully understood. Inflammatory bowel disease (IBD) has both genetic and environmental etiologies that lead to the breakdown of the epithelial barrier. In this review, we explore the up-to-date evidence that implicates mucin in the pathogenesis of IBD. In IBD, quantitative changes in mucin secretion occur, as well as structural changes in mucin's glycoprotein core and the sulfation and sialylation of mucin's oligosaccharide residues. These changes are associated with a diminished functionality of the mucous barrier. We identify the various genetic mutations associated with these changes and outline the animal models that have enhanced the current understanding of the genetic basis for IBD. Further study is needed to better characterize the immune and genetic influences on mucin expression and secretion and role of endoplasmic reticulum stress and a defective unfolded protein response in mediating these changes. PMID:23164684

  9. Long-term cultures of polarized airway epithelial cells from patients with cystic fibrosis.

    PubMed

    Wiszniewski, Ludovic; Jornot, Lan; Dudez, Tecla; Pagano, Alessandra; Rochat, Thierry; Lacroix, Jean Silvain; Suter, Susanne; Chanson, Marc

    2006-01-01

    The poor ability of respiratory epithelial cells to proliferate and differentiate in vitro into a pseudostratified mucociliated epithelium limits the general use of primary airway epithelial cell (AEC) cultures generated from patients with rare diseases, such as cystic fibrosis (CF). Here, we describe a procedure to amplify AEC isolated from nasal polyps and generate long-term cultures of the respiratory epithelium. AEC were seeded onto microporous permeable supports that carried on their undersurface a preformed feeder layer of primary human airway fibroblasts. The use of fibroblast feeder layers strongly stimulated the proliferation of epithelial cells, allowing the expansion of the cell pool with successive passages. AEC at increasing passage were seeded onto supports undercoated with airway fibroblasts and exposed to air. Either freshly isolated or amplified AEC could differentiate into a pseudostratified mucociliated epithelium for at least 10 mo. Thus, CF epithelia cultures showed elevated Na+ transport, drastic hyperabsorption of surface liquid, and absence of cAMP-induced Cl- secretion as compared with non-CF cultures. They were also characterized by thick apical secretion that hampered the movement of cell surface debris by cilia. However, CF respiratory epithelia did not show increased production of mucins or IL-8. The method described here is now routinely used in our laboratory to establish long-term cultures of well differentiated respiratory epithelia from human airway biopsies. PMID:16179582

  10. Dual oxidase regulates neutrophil recruitment in allergic airways.

    PubMed

    Chang, Sandra; Linderholm, Angela; Franzi, Lisa; Kenyon, Nicholas; Grasberger, Helmut; Harper, Richart

    2013-12-01

    Enhanced reactive oxygen species production in allergic airways is well described and correlates with increased airway contractions, inflammatory cell infiltration, goblet cell metaplasia, and mucus hypersecretion. There is also an abundance of interleukin-4/interleukin-13 (IL-4/IL-13)- or interleukin-5-secreting cells that are thought to be central to the pathogenesis of allergic asthma. We postulated that the dual oxidases (DUOX1 and DUOX2), members of the nicotinamide adenine dinucleotide phosphate oxidase family that release hydrogen peroxide (H2O2) in the respiratory tract, are critical proteins in the pathogenesis of allergic airways. DUOX activity is regulated by cytokines, including IL-4 and IL-13, and DUOX-mediated H2O2 influences several important features of allergic asthma: mucin production, IL-8 secretion, and wound healing. The objective of this study was to establish the contribution of DUOXs to the development of allergic asthma in a murine model. To accomplish this goal, we utilized a DUOXA-deficient mouse model (Duoxa(-/-)) that lacked maturation factors for both DUOX1 and DUOX2. Our results are the first to demonstrate evidence of DUOX protein and DUOX functional activity in murine airway epithelium. We also demonstrate that DUOXA maturation factors are required for airway-specific H2O2 production and localization of DUOX to cilia of fully differentiated airway epithelial cells. We compared wild-type and Duoxa(-/-) mice in an ovalbumin exposure model to determine the role of DUOX in allergic asthma. In comparison to DUOX-intact mice, Duoxa(-/-) mice had reduced mucous cell metaplasia and lower levels of TH2 cytokine levels in bronchoalveolar fluid. In addition, increased airway resistance in response to methacholine was observed in Duoxa(+/+) mice, as expected, but was absent in Duoxa(-/-) mice. Surprisingly, Duoxa(-/-) mice had decreased influx of neutrophils in bronchoalveolar fluid and lung tissue sections associated with a lower level of the

  11. Dual Oxidase Regulates Neutrophil Recruitment in Allergic Airways

    PubMed Central

    Chang, Sandra; Linderholm, Angela; Franzi, Lisa; Kenyon, Nicholas; Grasberger, Helmut; Harper, Richart

    2013-01-01

    Enhanced reactive oxygen species production in allergic airways is well described, and correlates with increased airway contractions, inflammatory cell infiltration, goblet cell metaplasia, and mucus hypersecretion. There is also an abundance of interleukin-4/interleukin-13 (IL-4/IL-13) or interleukin-5-secreting cells that are thought to be central to the pathogenesis of allergic asthma. We postulated that dual oxidases (DUOX1 and DUOX2), members of the nicotinamide adenine dinucleotide phosphate oxidase family that release hydrogen peroxide (H2O2) in the respiratory tract, are critical proteins in the pathogenesis of allergic airways. DUOX activity is regulated by cytokines including IL-4 and IL-13, and DUOX-mediated H2O2 influences several important features of allergic asthma: mucin production, IL-8 secretion, and wound healing. The objective of this study was to establish the contribution of DUOX to the development of allergic asthma in a murine model. To accomplish this goal, we utilized a DUOXA-deficient mouse model (Duoxa−/−) that lacked maturation factors for both DUOX1 and DUOX2. Our results are the first to demonstrate evidence of DUOX protein and DUOX functional activity in murine airway epithelium. We also demonstrate that DUOXA maturation factors are required for airway-specific H2O2 production and localization of DUOX to cilia of fully differentiated airway epithelial cells. We compared wild-type and Duoxa−/− mice in an ovalbumin exposure model to determine the role of DUOX in allergic asthma. In comparison to DUOX-intact mice, Duoxa−/− mice had reduced mucous cell metaplasia, and lower levels of TH2 cytokine levels in bronchoalveolar fluid. In addition, increased airway resistance in response to methacholine was observed in Duoxa+/+ mice as expected, but was absent in Duoxa−/− mice. Surprisingly, Duoxa−/− mice had decreased influx of neutrophils in bronchoalveolar fluid and lung tissue sections associated with a lower level of

  12. Aeromonas salmonicida binds differentially to mucins isolated from skin and intestinal regions of Atlantic salmon in an N-acetylneuraminic acid-dependent manner.

    PubMed

    Padra, János T; Sundh, Henrik; Jin, Chunsheng; Karlsson, Niclas G; Sundell, Kristina; Lindén, Sara K

    2014-12-01

    Aeromonas salmonicida subsp. salmonicida infection, also known as furunculosis disease, is associated with high morbidity and mortality in salmonid aquaculture. The first line of defense the pathogen encounters is the mucus layer, which is predominantly comprised of secreted mucins. Here we isolated and characterized mucins from the skin and intestinal tract of healthy Atlantic salmon and studied how A. salmonicida bound to them. The mucins from the skin, pyloric ceca, and proximal and distal intestine mainly consisted of mucins soluble in chaotropic agents. The mucin density and mucin glycan chain length from the skin were lower than were seen with mucin from the intestinal tract. A. salmonicida bound to the mucins isolated from the intestinal tract to a greater extent than to the skin mucins. The mucins from the intestinal regions had higher levels of sialylation than the skin mucins. Desialylating intestinal mucins decreased A. salmonicida binding, whereas desialylation of skin mucins resulted in complete loss of binding. In line with this, A. salmonicida also bound better to mammalian mucins with high levels of sialylation, and N-acetylneuraminic acid appeared to be the sialic acid whose presence was imperative for binding. Thus, sialylated structures are important for A. salmonicida binding, suggesting a pivotal role for sialylation in mucosal defense. The marked differences in sialylation as well as A. salmonicida binding between the skin and intestinal tract suggest interorgan differences in the host-pathogen interaction and in the mucin defense against A. salmonicida. PMID:25287918

  13. Ocular surface mucins and local inflammation-studies in genetically modified mouse lines.

    PubMed

    Shirai, Kumi; Saika, Shizuya

    2015-01-01

    Mucins locate to the apical surfaces of all wet-surfaced epithelia including ocular surface. The functions of the mucins include anti-adhesive, lubrication, water retention, allergens and pathogen barrier function. Ocular surface pathologies, i.e. dry eye syndrome or allergic conjunctivitis, are reportedly associated with alteration of expression pattern of mucin components. Recent investigations indicated anti-bacterial adhesion or anti-inflammatory effects of members of mucins in non-ocular tissues, i.e., gastrointestinal tracts or airway tissues, by using genetically modified mouse lines that lacks an expression of a mucin member. However, examination of ocular phenotypes of each of mucin gene-ablated mouse lines has not yet fully performed. Muc16-dficient mouse is associated with spontaneous subclinical inflammation in conjunctiva. The article reviews the roles of mucin members in modulation of local inflammation in mucous membrane tissues and phenotype of mouse lines with the loss of a mucin gene. Analysis of ocular surface of mucin-gene related mutant mouse lines are to be further performed. PMID:26818460

  14. House dust exposure mediates gut microbiome Lactobacillus enrichment and airway immune defense against allergens and virus infection.

    PubMed

    Fujimura, Kei E; Demoor, Tine; Rauch, Marcus; Faruqi, Ali A; Jang, Sihyug; Johnson, Christine C; Boushey, Homer A; Zoratti, Edward; Ownby, Dennis; Lukacs, Nicholas W; Lynch, Susan V

    2014-01-14

    Exposure to dogs in early infancy has been shown to reduce the risk of childhood allergic disease development, and dog ownership is associated with a distinct house dust microbial exposure. Here, we demonstrate, using murine models, that exposure of mice to dog-associated house dust protects against ovalbumin or cockroach allergen-mediated airway pathology. Protected animals exhibited significant reduction in the total number of airway T cells, down-regulation of Th2-related airway responses, as well as mucin secretion. Following dog-associated dust exposure, the cecal microbiome of protected animals was extensively restructured with significant enrichment of, amongst others, Lactobacillus johnsonii. Supplementation of wild-type animals with L. johnsonii protected them against both airway allergen challenge or infection with respiratory syncytial virus. L. johnsonii-mediated protection was associated with significant reductions in the total number and proportion of activated CD11c(+)/CD11b(+) and CD11c(+)/CD8(+) cells, as well as significantly reduced airway Th2 cytokine expression. Our results reveal that exposure to dog-associated household dust results in protection against airway allergen challenge and a distinct gastrointestinal microbiome composition. Moreover, the study identifies L. johnsonii as a pivotal species within the gastrointestinal tract capable of influencing adaptive immunity at remote mucosal surfaces in a manner that is protective against a variety of respiratory insults. PMID:24344318

  15. The O-Linked Glycome and Blood Group Antigens ABO on Mucin-Type Glycoproteins in Mucinous and Serous Epithelial Ovarian Tumors

    PubMed Central

    Vitiazeva, Varvara; Kattla, Jayesh J.; Flowers, Sarah A.; Lindén, Sara K.; Premaratne, Pushpa; Weijdegård, Birgitta; Sundfeldt, Karin; Karlsson, Niclas G.

    2015-01-01

    Background Mucins are heavily O-glycosylated proteins where the glycosylation has been shown to play an important role in cancer. Normal epithelial ovarian cells do not express secreted mucins, but their abnormal expression has previously been described in epithelial ovarian cancer and may relate to tumor formation and progression. The cyst fluids were shown to be a rich source for acidic glycoproteins. The study of these proteins can potentially lead to the identification of more effective biomarkers for ovarian cancer. Methods In this study, we analyzed the expression of the MUC5AC and the O-glycosylation of acidic glycoproteins secreted into ovarian cyst fluids. The samples were obtained from patients with serous and mucinous ovarian tumors of different stages (benign, borderline, malignant) and grades. The O-linked oligosaccharides were released and analyzed by negative-ion graphitized carbon Liquid Chromatography (LC) coupled to Electrospray Ionization tandem Mass Spectrometry (ESI-MSn). The LC-ESI-MSn of the oligosaccharides from ovarian cyst fluids displayed differences in expression of fucose containing structures such as blood group ABO antigens and Lewis-type epitopes. Results The obtained data showed that serous and mucinous benign adenomas, mucinous low malignant potential carcinomas (LMPs, borderline) and mucinous low-grade carcinomas have a high level of blood groups and Lewis type epitopes. In contrast, this type of fucosylated structures were low abundant in the high-grade mucinous carcinomas or in serous carcinomas. In addition, the ovarian tumors that showed a high level of expression of blood group antigens also revealed a strong reactivity towards the MUC5AC antibody. To visualize the differences between serous and mucinous ovarian tumors based on the O-glycosylation, a hierarchical cluster analysis was performed using mass spectrometry average compositions (MSAC). Conclusion Mucinous benign and LMPs along with mucinous low-grade carcinomas

  16. A Primary Retroperitoneal Mucinous Tumor

    PubMed Central

    Heelan Gladden, Alicia A.; Wohlauer, Max; McManus, Martine C.; Gajdos, Csaba

    2015-01-01

    A twenty-five-year-old female presented with a large retroperitoneal mass. Workup included history and physical exam, imaging, biopsy, colonoscopy, and gynecologic exam. After surgical resection, the mass was determined to be a primary retroperitoneal mucinous tumor (PRMT). Clinically and histologically, these tumors are similar pancreatic and ovarian mucinous neoplasms. PRMTs are rare and few case reports have been published. PRMTs are divided into mucinous cystadenomas, mucinous borderline tumors of low malignant potential, and mucinous carcinoma. These tumors have malignant potential so resection is indicated and in some cases adjuvant chemotherapy and/or surveillance imaging. PMID:25874152

  17. Macromolecular properties and polymeric structure of canine tracheal mucins.

    PubMed Central

    Shankar, V; Virmani, A K; Naziruddin, B; Sachdev, G P

    1991-01-01

    Two high-Mr mucus glycoproteins (mucins), CTM-A and CTM-B, were highly purified from canine tracheal pouch secretions, and their macromolecular properties as well as polymeric structure were investigated. On SDS/composite-gel electrophoresis, a diffuse band was observed for each mucin. Polyacrylamide-gel electrophoresis using 6% gels also showed the absence of low-Mr contaminants in the mucins. Comparison of chemical and amino acid compositions revealed significant differences between the two mucins. Using a static-laser-light-scattering technique, CTM-A and CTM-B were found to have weight-average Mr values of about 11.0 x 10(6) and 1.4 x 10(6) respectively. Both mucins showed concentration-dependent aggregation in buffer containing 6 M-guanidine hydrochloride. Under similar experimental conditions, reduced-alkylated CTM-A had an Mr of 5.48 x 10(6) and showed no concentration-dependent aggregation. Hydrophobic properties of the mucins, investigated by the fluorescent probe technique using mansylphenylalanine as the probe, showed the presence of a large number of low-affinity (KD approx. 10(5) M) binding sites. These sites appeared to be located on the non-glycosylated regions of the protein core, since Pronase digestion of the mucins almost completely eliminated probe binding. Reduction of disulphide bonds of CTM-A and CTM-B did not significantly alter the probe-binding properties. Also, addition of increasing NaCl concentrations (0.03-1.0 M) to the buffer caused only a small change in the hydrophobic properties of native and reduced-alkylated mucins. CTM-A was deglycosylated, without notable in the hydrophobic properties of native and reduced-alkylated mucins. CTM-A was deglycosylated, without notable degradation, using a combination of chemical and enzymic methods. On SDS/PAGE the protein core was estimated to have an Mr of approx. 60,000. On the basis of the protein and carbohydrate contents of the major mucin CTM-A, the mucin monomer was calculated to have an

  18. Transforming Growth Factor-β2 Induces Bronchial Epithelial Mucin Expression in Asthma

    PubMed Central

    Chu, Hong Wei; Balzar, Silvana; Seedorf, Gregory J.; Westcott, Jay Y.; Trudeau, John B.; Silkoff, Phil; Wenzel, Sally E.

    2004-01-01

    The transforming growth factor (TGF)-β family is important for tissue repair in pathological conditions including asthma. However, little is known about the impact of either TGF-β1 or TGF-β2 on asthmatic airway epithelial mucin expression. We evaluated bronchial epithelial TGF-β1 and TGF-β2 expression and their effects on mucin expression, and the role of TGF-β1 or TGF-β2 in interleukin (IL)-13-induced mucin expression. Epithelial TGF-β1, TGF-β2, and mucin expression were evaluated in endobronchial biopsies from asthmatics and normal subjects. The effects of TGF-β1 or TGF-β2 on mucin MUC5AC protein and mRNA expression, and the impact of IL-13 on epithelial TGF-β1, TGF-β2, and MUC5AC were determined in cultured bronchial epithelial cells from endobronchial brushings of both subject groups. In biopsy tissue, epithelial TGF-β2 expression levels were higher than TGF-β1 in both asthmatics and normals. TGF-β2, but not TGF-β1, was increased in asthmatics compared with normals, and significantly correlated with mucin expression. TGF-β2, but not TGF-β1, increased mucin expression in cultured epithelial cells from both subject groups. IL-13 increased the release of TGF-β2, but not TGF-β1, from epithelial cells. A neutralizing TGF-β2 antibody partially inhibited IL-13-induced mucin expression. These data suggest that TGF-β2 production by asthmatic bronchial epithelial cells may increase airway mucin expression. IL-13-induced mucin expression may occur in part through TGF-β2 up-regulation. PMID:15466377

  19. Transforming growth factor-beta2 induces bronchial epithelial mucin expression in asthma.

    PubMed

    Chu, Hong Wei; Balzar, Silvana; Seedorf, Gregory J; Westcott, Jay Y; Trudeau, John B; Silkoff, Phil; Wenzel, Sally E

    2004-10-01

    The transforming growth factor (TGF)-beta family is important for tissue repair in pathological conditions including asthma. However, little is known about the impact of either TGF-beta1 or TGF-beta2 on asthmatic airway epithelial mucin expression. We evaluated bronchial epithelial TGF-beta1 and TGF-beta2 expression and their effects on mucin expression, and the role of TGF-beta1 or TGF-beta2 in interleukin (IL)-13-induced mucin expression. Epithelial TGF-beta1, TGF-beta2, and mucin expression were evaluated in endobronchial biopsies from asthmatics and normal subjects. The effects of TGF-beta1 or TGF-beta2 on mucin MUC5AC protein and mRNA expression, and the impact of IL-13 on epithelial TGF-beta1, TGF-beta2, and MUC5AC were determined in cultured bronchial epithelial cells from endobronchial brushings of both subject groups. In biopsy tissue, epithelial TGF-beta2 expression levels were higher than TGF-beta1 in both asthmatics and normals. TGF-beta2, but not TGF-beta1, was increased in asthmatics compared with normals, and significantly correlated with mucin expression. TGF-beta2, but not TGF-beta1, increased mucin expression in cultured epithelial cells from both subject groups. IL-13 increased the release of TGF-beta2, but not TGF-beta1, from epithelial cells. A neutralizing TGF-beta2 antibody partially inhibited IL-13-induced mucin expression. These data suggest that TGF-beta2 production by asthmatic bronchial epithelial cells may increase airway mucin expression. IL-13-induced mucin expression may occur in part through TGF-beta2 up-regulation. PMID:15466377

  20. Chemically tunable mucin chimeras assembled on living cells

    PubMed Central

    Kramer, Jessica R.; Onoa, Bibiana; Bustamante, Carlos; Bertozzi, Carolyn R.

    2015-01-01

    Mucins are a family of secreted and transmembrane glycoproteins characterized by a massive domain of dense O-glycosylation on serine and threonine residues. Mucins are intimately involved in immunity and cancer, yet elucidation of the biological roles of their glycodomains has been complicated by their massive size, domain polymorphisms, and variable glycosylation patterns. Here we developed a synthetic route to a library of compositionally defined, high-molecular weight, dual end-functionalized mucin glycodomain constructs via N-carboxyanhydride polymerization. These glycopolypeptides are the first synthetic analogs to our knowledge to feature the native α-GalNAc linkage to serine with molecular weights similar to native mucins, solving a nearly 50-year synthetic challenge. Physical characterization of the mimics revealed insights into the structure and properties of mucins. The synthetic glycodomains were end-functionalized with an optical probe and a tetrazine moiety, which allowed site-specific bioorthogonal conjugation to an engineered membrane protein on live mammalian cells. This strategy in protein engineering will open avenues to explore the biological roles of cell surface mucins. PMID:26420872

  1. Effects of calcium on intestinal mucin: implications for cystic fibrosis.

    PubMed

    Forstner, J F; Forstner, G G

    1976-06-01

    A major feature of the disease cystic fibrosis is the excessive concentration of mucus within ducts and glands of mucous-producing organs. Some mucous secretions also show an elevation in calcium concentration. Using purified rat intestinal goblet cell mucin as a model mucin, we have investigated the effect of millimolar additions (1-25 mM) of CaCl2 on the physical properties of the mucin. Isotonicity of incubation media was preserved in order to mimic in vivo conditions. CaCl2 (8-15mM) caused a 15-33% decrease in viscosity, no change in electrophoretic mobility in acrylamide gels, and a 20-30% decrease in solubility of the mucin. Solubility changes were reversed by the addition of EDTA (20 mM) to incubations. Insolubility was also produced in incubations of mucin with a mixture of soluble intestinal contents (NaCl washings). These findings strongly suggest that the mucin became smaller and more dense as calcium was added, a process most probably achieved by loss of intramolecular water. PMID:1272637

  2. FTIR Study On The Secondary Structure Of Mucin From Mucinous Cystadenoma Of The Ovary

    NASA Astrophysics Data System (ADS)

    Shen, Keng; Wu, Paochen; Zhou, Weij in; Liu, Fuan; Guo, Hai; Wu, Jinguang

    1989-12-01

    The mucinous cystadenoma, a common benign neoplasm of the ovary, may sometime bring about a fatal outcome known as pseudomyxoma peritonei which is characterized by massive accumulation of mucinous substance in the peritoneal cavity, resulting in extensive adhesions, chronic progressive intestinal obstruction and finally death of the patient. Surgical approach to this condition proves to be a palliative procedure. Repeated operation can only remove part of the geletinous material and reaccumulation of mucus within 1-2 years after the initial surgery is almost a rule. In view of the benign histologic nature of the disease, chemotherapy, either systemic or intraperitoneal, and radiotherapy are generally ineffective in arresting the progression of the pathologic process and preventing the reaccumulation of mucus. Therefore, the only hope lies on the introduction into the peritoneal cavity some agents which may dissolve the accumulated mucin, relieve the intestinal obstruction, and consequently, prolong and even save the life f the patient. Based on this conception, sporadic articles by a few authors(1,2)ap-peared in the literature reporting their clinical experience with different mucolytic agents. However, some blindness would inevitably be involved in such investigations due to the lack of a comprehensive understanding of the chemical structures of the substance. The purpose of the present paper is to report our preliminary results of study of the secondary structures of mucin secreted by this special type of tumor.

  3. Detecting, visualising, and quantifying mucins.

    PubMed

    Harrop, Ceri A; Thornton, David J; McGuckin, Michael A

    2012-01-01

    The extreme size, extensive glycosylation, and gel-forming nature of mucins make them a challenge to work with, and methodologies for the detection of mucins must take into consideration these features to ensure that one obtains both accurate and meaningful results. In understanding and appreciating the nature of mucins, this affords the researcher a valuable toolkit which can be used to full advantage in detecting, quantifying, and visualising mucins. The employment of a combinatorial approach to mucin detection, using antibody, chemical, and lectin detection methods, allows important information to be gleaned regarding the size, extent of glycosylation, specific mucin species, and distribution of mucins within a given sample. In this chapter, the researcher is guided through considerations into the structure of mucins and how this both affects the detection of mucins and can be used to full advantage. Techniques including ELISA, dot/slot blotting, and Western blotting, use of lectins and antibodies in mucin detection on membranes as well as immunohistochemistry and immunofluorescence on both tissues and cells grown on Transwell™ inserts are described. Notes along with each section advice the researcher on best practice and describe any associated limitations of a particular technique from which the researcher can further develop a particular protocol. PMID:22259129

  4. Normalization of raised sodium absorption and raised calcium-mediated chloride secretion by adenovirus-mediated expression of cystic fibrosis transmembrane conductance regulator in primary human cystic fibrosis airway epithelial cells.

    PubMed Central

    Johnson, L G; Boyles, S E; Wilson, J; Boucher, R C

    1995-01-01

    Cystic fibrosis airway epithelia exhibit a spectrum of ion transport properties that differ from normal, including not only defective cAMP-mediated Cl- secretion, but also increased Na+ absorption and increased Ca(2+)-mediated Cl- secretion. In the present study, we examined whether adenovirus-mediated (Ad5) transduction of CFTR can correct all of these CF ion transport abnormalities. Polarized primary cultures of human CF and normal nasal epithelial cells were infected with Ad5-CBCFTR at an moi (10(4)) which transduced virtually all cells or Ad5-CMV lacZ as a control. Consistent with previous reports, Ad5-CBCFTR, but not Ad5-CMV lacZ, corrected defective CF cAMP-mediated Cl- secretion. Basal Na+ transport rates (basal Ieq) in CF airway epithelial sheets (-78.5 +/- 9.8 microA/cm2) were reduced to levels measured in normal epithelial sheets (-30.0 +/- 2.0 microA/cm2) by Ad5-CBCFTR (-36.9 +/- 4.8 microA/cm2), but not Ad5-CMV lacZ (-65.8 +/- 6.1 microA/cm2). Surprisingly, a significant reduction in delta Ieq in response to ionomycin, a measure of Ca(2+)-mediated Cl- secretion, was observed in CFTR-expressing (corrected) CF epithelial sheets (-6.9 +/- 11.8 microA/cm2) when compared to uninfected CF epithelial sheets (-76.2 +/- 15.1 microA/cm2). Dose response effects of Ad5-CBCFTR on basal Na+ transport rates and Ca(2+)-mediated Cl- secretion suggest that the mechanism of regulation of these two ion transport functions by CFTR may be different. In conclusion, efficient transduction of CFTR corrects hyperabsorption of Na+ in primary CF airway epithelial cells and restores Ca(2+)-mediated Cl- secretion to levels observed in normal airway epithelial cells. Moreover, assessment of these ion transport abnormalities may represent important endpoints for testing the efficacy of gene therapy for cystic fibrosis. Images PMID:7533790

  5. Depletion of mucin in mucin-producing human gastrointestinal carcinoma: Results from in vitro and in vivo studies with bromelain and N-acetylcysteine

    PubMed Central

    Amini, Afshin; Masoumi-Moghaddam, Samar; Ehteda, Anahid; Liauw, Winston; Morris, David L.

    2015-01-01

    Aberrant expression of membrane-associated and secreted mucins, as evident in epithelial tumors, is known to facilitate tumor growth, progression and metastasis, and to provide protection against adverse growth conditions, chemotherapy and immune surveillance. Emerging evidence provides support for the oncogenic role of MUC1 in gastrointestinal carcinomas and relates its expression to an invasive phenotype. Similarly, mucinous differentiation of gastrointestinal tumors, in particular increased or de novo expression of MUC2 and/or MUC5AC, is widely believed to imply an adverse clinicopathological feature. Through formation of viscous gels, too, MUC2 and MUC5AC significantly contribute to the biology and pathogenesis of mucin-secreting gastrointestinal tumors. Here, we investigated the mucin-depleting effects of bromelain (BR) and N-acetylcysteine (NAC), in nine different regimens as single or combination therapy, in in vitro (MKN45, KATOIII and LS174T cell lines) and in vivo (female nude mice bearing intraperitoneal MKN45 and LS174T) settings. The inhibitory effects of the treatment on cancer cell growth and proliferation were also evaluated in vivo. Our results suggest that a combination of BR and NAC with dual effects on growth and mucin products of mucin-expressing tumor cells is a promising candidate towards the development of novel approaches to gastrointestinal malignancies with the involvement of mucin pathology. This capability supports the use of this combination formulation in locoregional approaches for reducing the adverse effects of the aberrantly secreted gel-forming mucins, as in pseudomyxoma peritonei and similar pathologies with ectopic production of mucin. PMID:26436698

  6. Depletion of mucin in mucin-producing human gastrointestinal carcinoma: Results from in vitro and in vivo studies with bromelain and N-acetylcysteine.

    PubMed

    Amini, Afshin; Masoumi-Moghaddam, Samar; Ehteda, Anahid; Liauw, Winston; Morris, David L

    2015-10-20

    Aberrant expression of membrane-associated and secreted mucins, as evident in epithelial tumors, is known to facilitate tumor growth, progression and metastasis, and to provide protection against adverse growth conditions, chemotherapy and immune surveillance. Emerging evidence provides support for the oncogenic role of MUC1 in gastrointestinal carcinomas and relates its expression to an invasive phenotype. Similarly, mucinous differentiation of gastrointestinal tumors, in particular increased or de novo expression of MUC2 and/or MUC5AC, is widely believed to imply an adverse clinicopathological feature. Through formation of viscous gels, too, MUC2 and MUC5AC significantly contribute to the biology and pathogenesis of mucin-secreting gastrointestinal tumors. Here, we investigated the mucin-depleting effects of bromelain (BR) and N-acetylcysteine (NAC), in nine different regimens as single or combination therapy, in in vitro (MKN45, KATOIII and LS174T cell lines) and in vivo (female nude mice bearing intraperitoneal MKN45 and LS174T) settings. The inhibitory effects of the treatment on cancer cell growth and proliferation were also evaluated in vivo. Our results suggest that a combination of BR and NAC with dual effects on growth and mucin products of mucin-expressing tumor cells is a promising candidate towards the development of novel approaches to gastrointestinal malignancies with the involvement of mucin pathology. This capability supports the use of this combination formulation in locoregional approaches for reducing the adverse effects of the aberrantly secreted gel-forming mucins, as in pseudomyxoma peritonei and similar pathologies with ectopic production of mucin. PMID:26436698

  7. Salivary Mucin 19 Glycoproteins

    PubMed Central

    Culp, David J.; Robinson, Bently; Cash, Melanie N.; Bhattacharyya, Indraneel; Stewart, Carol; Cuadra-Saenz, Giancarlo

    2015-01-01

    Saliva functions in innate immunity of the oral cavity, protecting against demineralization of teeth (i.e. dental caries), a highly prevalent infectious disease associated with Streptococcus mutans, a pathogen also linked to endocarditis and atheromatous plaques. Gel-forming mucins are a major constituent of saliva. Because Muc19 is the dominant salivary gel-forming mucin in mice, we studied Muc19−/− mice for changes in innate immune functions of saliva in interactions with S. mutans. When challenged with S. mutans and a cariogenic diet, total smooth and sulcal surface lesions are more than 2- and 1.6-fold higher in Muc19−/− mice compared with wild type, whereas the severity of lesions are up to 6- and 10-fold higher, respectively. Furthermore, the oral microbiota of Muc19−/− mice display higher levels of indigenous streptococci. Results emphasize the importance of a single salivary constituent in the innate immune functions of saliva. In vitro studies of S. mutans and Muc19 interactions (i.e. adherence, aggregation, and biofilm formation) demonstrate Muc19 poorly aggregates S. mutans. Nonetheless, aggregation is enhanced upon adding Muc19 to saliva from Muc19−/− mice, indicating Muc19 assists in bacterial clearance through formation of heterotypic complexes with salivary constituents that bind S. mutans, thus representing a novel innate immune function for salivary gel-forming mucins. In humans, expression of salivary MUC19 is unclear. We find MUC19 transcripts in salivary glands of seven subjects and demonstrate MUC19 glycoproteins in glandular mucous cells and saliva. Similarities and differences between mice and humans in the expression and functions of salivary gel-forming mucins are discussed. PMID:25512380

  8. Theophylline Represses IL-8 Secretion from Airway Smooth Muscle Cells Independently of Phosphodiesterase Inhibition. Novel Role as a Protein Phosphatase 2A Activator.

    PubMed

    Patel, Brijeshkumar S; Rahman, Md Mostafizur; Rumzhum, Nowshin N; Oliver, Brian G; Verrills, Nicole M; Ammit, Alaina J

    2016-06-01

    Theophylline is an old drug experiencing a renaissance owing to its beneficial antiinflammatory effects in chronic respiratory diseases, such as asthma and chronic obstructive pulmonary disease. Multiple modes of antiinflammatory action have been reported, including inhibition of the enzymes that degrade cAMP-phosphodiesterase (PDE). Using primary cultures of airway smooth muscle (ASM) cells, we recently revealed that PDE4 inhibitors can potentiate the antiinflammatory action of β2-agonists by augmenting cAMP-dependent expression of the phosphatase that deactivates mitogen-activated protein kinase (MAPK)-MAPK phosphatase (MKP)-1. Therefore, the aim of this study was to address whether theophylline repressed cytokine production in a similar, PDE-dependent, MKP-1-mediated manner. Notably, theophylline did not potentiate cAMP release from ASM cells treated with the long-acting β2-agonist formoterol. Moreover, theophylline (0.1-10 μM) did not increase formoterol-induced MKP-1 messenger RNA expression nor protein up-regulation, consistent with the lack of cAMP generation. However, theophylline (at 10 μM) was antiinflammatory and repressed secretion of the neutrophil chemoattractant cytokine IL-8, which is produced in response to TNF-α. Because theophylline's effects were independent of PDE4 inhibition or antiinflammatory MKP-1, we then wished to elucidate the novel mechanisms responsible. We investigated the impact of theophylline on protein phosphatase (PP) 2A, a master controller of multiple inflammatory signaling pathways, and show that theophylline increases TNF-α-induced PP2A activity in ASM cells. Confirmatory results were obtained in A549 lung epithelial cells. PP2A activators have beneficial effects in ex vivo and in vivo models of respiratory disease. Thus, our study is the first to link theophylline with PP2A activation as a novel mechanism to control respiratory inflammation. PMID:26574643

  9. Characterization of pig colonic mucins.

    PubMed Central

    Fogg, F J; Hutton, D A; Jumel, K; Pearson, J P; Harding, S E; Allen, A

    1996-01-01

    Pig colonic mucins isolated from the adherent mucus gel in the presence of proteinase inhibitors were solubilized by homogenization and the component mucins fractionated by CsC1 density-gradient centrifugation. Polymeric and reduced pig colonic mucin were both largely excluded on Sepharose CL-2B, papain-digested colonic mucin was included. The M(r) values of polymeric, reduced and digested mucins were 5.5 x 10(6), 2.1 x 10(6) and 0.6 x 10(6) respectively. This suggests that pig colonic mucin is comprised of 2-3 subunits, each subunit containing 3-4 glycosylated regions. The intrinsic viscosities of polymeric, reduced and digested mucin were 240 ml.g-1, 100 ml.g-1 and 20 ml.g-1 respectively. Polymeric pig colonic mucin comprised 16% protein per mg of glycoprotein and was rich in serine, threonine and proline (43% of total amino acids). There were approx. 150 disulphide bridges and 53 free thiol groups per mucin polymer. A seventh of the protein content was lost on reduction. This protein was particularly rich in proline and the hydrophobic amino acids. Papain-digested pig colonic mucin contained 11% protein per mg of glycoprotein and was rich in serine, threonine, glutamate and aspartate. All types of amino acids with the exception of aspartate were lost on digestion. The amino acid analysis of the proteolytically digested regions of pig colonic mucin are markedly different to the tandem repeat regions of the human mucin genes shown to be expressed in the colon. PMID:8670173

  10. Candida albicans Shed Msb2 and Host Mucins Affect the Candidacidal Activity of Salivary Hst 5

    PubMed Central

    Puri, Sumant; Friedman, Justin; Saraswat, Darpan; Kumar, Rohitashw; Li, Rui; Ruszaj, Donna; Edgerton, Mira

    2015-01-01

    Salivary Histatin 5 (Hst 5) is an antimicrobial peptide that exhibits potent antifungal activity towards Candida albicans, the causative agent of oral candidiasis. However, it exhibits limited activity in vivo, largely due to inactivation by salivary components of both host and pathogen origin. Proteins secreted by C. albicans during infection such as secreted aspartyl proteases (Saps) and shed mucin Msb2 can reduce Hst 5 activity; and human salivary mucins, while suggested to protect Hst 5 from proteolytic degradation, can entrap peptides into mucin gels, thereby reducing bioavailability. We show here that Sap6 that is secreted during hyphal growth reduces Hst 5 activity, most likely a result of proteolytic degradation of Hst 5 since this effect is abrogated with heat inactivated Sap 6. We further show that just like C. albicans shedding Msb2, mammalian mucins, fetuin and porcine gut mucin (that is related to salivary mucins), also reduce Hst 5 activity. However, we identify mucin-like protein-induced changes in C. albicans cell morphology and aggregation patterns, suggesting that the effect of such proteins on Hst 5 cannot be interpreted independently of their effect on yeast cells. PMID:26529023

  11. Mucin production by human colonic carcinoma cells correlates with their metastatic potential in animal models of colon cancer metastasis.

    PubMed Central

    Bresalier, R S; Niv, Y; Byrd, J C; Duh, Q Y; Toribara, N W; Rockwell, R W; Dahiya, R; Kim, Y S

    1991-01-01

    Patients with mucinous colorectal cancers characteristically present with advanced disease, however, the relationship between mucin production by colon cancer cells and their metastatic potential remains unclear. We therefore sought to define the relationship between mucin production by human colon cancer cells and metastatic ability by employing animal models of colon cancer metastasis. LS LiM 6, a colon carcinoma cell line with high liver metastasizing ability during cecal growth in nude mice produced twofold more metabolically labeled intracellular mucin and secreted four- to fivefold more mucin into the culture medium compared to poorly metastatic parental line LS174T. This was accompanied by a similar elevation in poly(A)+ RNA detected by blot hybridization with a human intestinal mucin cDNA probe, and increases in mucin core carbohydrate antigens determined immunohistochemically. Variants of LS174T selected for high (HM 7) or low (LM 12) mucin synthesizing capacity also yielded metastases after cecal growth and colonized the liver after splenic-portal injection in proportion to their ability to produce mucin. Inhibition of mucin glycosylation by the arylglycoside benzyl-alpha-N-acetyl-galactosamine greatly reduced liver colonization after splenic-portal injection of the tumor cells. These data suggest that mucin production by human colon cancer cells correlates with their metastatic potential and affects their ability to colonize the liver in experimental model systems. Images PMID:1999484

  12. A crucial role of Flagellin in the induction of airway mucus production by Pseudomonas aeruginosa.

    PubMed

    Ben Mohamed, Fatima; Mohamed, Fatima Ben; Garcia-Verdugo, Ignacio; Medina, Mathieu; Balloy, Viviane; Chignard, Michel; Ramphal, Reuben; Touqui, Lhousseine

    2012-01-01

    Pseudomonas aeruginosa is an opportunistic pathogen involved in nosocomial infections. Flagellin is a P. aeruginosa virulence factor involved in host response to this pathogen. We examined the role of flagellin in P. aeruginosa-induced mucus secretion. Using a mouse model of pulmonary infection we showed that PAK, a wild type strain of P. aeruginosa, induced airway mucus secretion and mucin muc5ac expression at higher levels than its flagellin-deficient mutant (ΔFliC). PAK induced expression of MUC5AC and MUC2 in both human airway epithelial NCI-H292 cell line and in primary epithelial cells. In contrast, ΔFliC infection had lower to no effect on MUC5AC and MUC2 expressions. A purified P. aeruginosa flagellin induced MUC5AC expression in parallel to IL-8 secretion in NCI-H292 cells. Accordingly, ΔFliC mutant stimulated IL-8 secretion at significantly lower levels compared to PAK. Incubation of NCI-H292 cells with exogenous IL-8 induced MUC5AC expression and pre-incubation of these cells with an anti-IL-8 antibody abrogated flagellin-mediated MUC5AC expression. Silencing of TLR5 and Naip, siRNA inhibited both flagellin-induced MUC5AC expression and IL-8 secretion. Finally, inhibition of ERK abolished the expression of both PAK- and flagellin-induced MUC5AC. We conclude that: (i) flagellin is crucial in P. aeruginosa-induced mucus hyper-secretion through TLR5 and Naip pathways; (ii) this process is mediated by ERK and amplified by IL-8. Our findings help understand the mechanisms involved in mucus secretion during pulmonary infectious disease induced by P. aeruginosa, such as in cystic fibrosis. PMID:22768318

  13. Gelation of mucin: Protecting the stomach from autodigestion

    NASA Astrophysics Data System (ADS)

    Bansil, Rama

    2011-03-01

    In this talk I will describe the molecular mechanisms involved in the remarkable ability of the mucus lining of the stomach for protecting the stomach from being digested by the acidic gastric juices that it secretes. These physical properties can be attributed to the presence of a high molecular weight glycoprotein found in mucus, called mucin. Rheology and other measurements show that gastric mucin forms a gel under acidic pH. A model of gelation based on the interplay of hydrophobic and electrostatic interactions will be discussed. Molecular Dynamics simulation studies of folding and aggregation of mucin domains provide further support for this model. The relevance of gelation to the motion of the ulcer causing bacterium H. pylori will be discussed.

  14. Analysis of the Distribution of Mucins in Adult Human Gastric Mucosa and Its Functional Significance

    PubMed Central

    2016-01-01

    Introduction Mucins are complex composition of carbohydrates seen in the epithelial cells lining the gastrointestinal tract (GIT). Normal distribution of such mucins in different part of the GIT and its alteration in various inflammatory, benign and malignant lesions of GIT has aroused interest in the field of histochemistry. Aim By applying variety of histochemical techniques an attempt has been made to draw a map of mucin secretion by the different epithelial cell types in different parts of the stomach. Materials and Methods Fifty samples were taken each from different parts of the stomach like fundus, body and pylorus, from dissected fresh specimens (total of 150 specimens). Tissue samples were subjected for routine process and studied for histological and different histochemical staining. Results Mucin pattern in adult predominantly secretes neutral mucosubstances. Surface epithelium shows predominant neutral mucin while cardiac and gastric glands with foveolar cells show moderate amount. Sialomucin is present in a few cells of the surface epithelium, foveolar cells and in most of the mucous neck cells. Small amount of sialomucin and sulphomucin are found in surface epithelial foveolar cells while traces of sulphomucin are found in deep foveolar cells. Mucous neck cells secrete both sulphomucin and sialomucin. Conclusion Normal gastric mucosa adjacent to gastric ulcers and malignant tumours of stomach secretes mucins which differ histochemically and biochemically from that of normal. Early recognition of such changes could be useful in recognizing the different type of carcinomas and their prognosis. PMID:27042436

  15. Glucagon Like Peptide-1 (GLP-1) Modulates OVA-Induced Airway Inflammation and Mucus Secretion Involving a Protein Kinase A (PKA)-Dependent Nuclear Factor-κB (NF-κB) Signaling Pathway in Mice

    PubMed Central

    Zhu, Tao; Wu, Xiao-ling; Zhang, Wei; Xiao, Min

    2015-01-01

    Asthma is a common chronic pulmonary inflammatory disease, featured with mucus hyper-secretion in the airway. Recent studies found that glucagon like peptide-1 (GLP-1) analogs, including liraglutide and exenatide, possessed a potent anti-inflammatory property through a protein kinase A (PKA)-dependent signaling pathway. Therefore, the aim of current study was to investigate the value of GLP-1 analog therapy liraglutide in airway inflammation and mucus secretion in a murine model of ovalbumin (OVA)-induced asthma, and its underlying molecular mechanism. In our study, BALB/c mice were sensitized and challenged by OVA to induce chronic asthma. Pathological alterations, the number of cells and the content of inflammatory mediators in bronchoalveolar lavage fluid (BALF), and mucus secretion were observed and measured. In addition, the mRNA and protein expression of E-selectin and MUC5AC were analyzed by qPCR and Western blotting. Then, the phosphorylation of PKA and nuclear factor-κB (NF-κB) p65 were also measured by Western blotting. Further, NF-κB p65 DNA binding activity was detected by ELISA. OVA-induced airway inflammation, airway mucus hyper-secretion, the up-regulation of E-selectin and MUC5AC were remarkably inhibited by GLP-1 in mice (all p < 0.01). Then, we also found that OVA-reduced phosphorylation of PKA, and OVA-enhanced NF-κB p65 activation and NF-κB p65 DNA binding activity were markedly improved by GLP-1 (all p < 0.01). Furthermore, our data also figured out that these effects of GLP-1 were largely abrogated by the PKA inhibitor H-89 (all p < 0.01). Taken together, our results suggest that OVA-induced asthma were potently ameliorated by GLP-1 possibly through a PKA-dependent inactivation of NF-κB in mice, indicating that GLP-1 analogs may be considered an effective and safe drug for the potential treatment of asthma in the future. PMID:26343632

  16. Epinephrine Activation of the β2-Adrenoceptor Is Required for IL-13-Induced Mucin Production in Human Bronchial Epithelial Cells

    PubMed Central

    Al-Sawalha, Nour; Pokkunuri, Indira; Omoluabi, Ozozoma; Kim, Hosu; Thanawala, Vaidehi J.; Hernandez, Adrian; Bond, Richard A.; Knoll, Brian J.

    2015-01-01

    Mucus hypersecretion by airway epithelium is a hallmark of inflammation in allergic asthma and results in airway narrowing and obstruction. Others have shown that administration a TH2 cytokine, IL-13 is sufficient to cause mucus hypersecretion in vivo and in vitro. Asthma therapy often utilizes β2-adrenoceptor (β2AR) agonists, which are effective acutely as bronchodilators, however chronic use may lead to a worsening of asthma symptoms. In this study, we asked whether β2AR signaling in normal human airway epithelial (NHBE) cells affected mucin production in response to IL-13. This cytokine markedly increased mucin production, but only in the presence of epinephrine. Mucin production was blocked by ICI-118,551, a preferential β2AR antagonist, but not by CGP-20712A, a preferential β1AR antagonist. Constitutive β2AR activity was not sufficient for IL-13 induced mucin production and β-agonist-induced signaling is required. A clinically important long-acting β-agonist, formoterol, was as effective as epinephrine in potentiating IL-13 induced MUC5AC transcription. IL-13 induced mucin production in the presence of epinephrine was significantly reduced by treatment with selective inhibitors of ERK1/2 (FR180204), p38 (SB203580) and JNK (SP600125). Replacement of epinephrine with forskolin + IBMX resulted in a marked increase in mucin production in NHBE cells in response to IL-13, and treatment with the inhibitory cAMP analogue Rp-cAMPS decreased mucin levels induced by epinephrine + IL-13. Our findings suggest that β2AR signaling is required for mucin production in response to IL-13, and that mitogen activated protein kinases and cAMP are necessary for this effect. These data lend support to the notion that β2AR-agonists may contribute to asthma exacerbations by increasing mucin production via activation of β2ARs on epithelial cells. PMID:26161982

  17. Mucins as Diagnostic and Prognostic Biomarkers in a Fish-Parasite Model: Transcriptional and Functional Analysis

    PubMed Central

    Pérez-Sánchez, Jaume; Estensoro, Itziar; Redondo, María José; Calduch-Giner, Josep Alvar; Kaushik, Sadasivam; Sitjà-Bobadilla, Ariadna

    2013-01-01

    Mucins are O-glycosylated glycoproteins present on the apex of all wet-surfaced epithelia with a well-defined expression pattern, which is disrupted in response to a wide range of injuries or challenges. The aim of this study was to identify mucin gene sequences of gilthead sea bream (GSB), to determine its pattern of distribution in fish tissues and to analyse their transcriptional regulation by dietary and pathogenic factors. Exhaustive search of fish mucins was done in GSB after de novo assembly of next-generation sequencing data hosted in the IATS transcriptome database (www.nutrigroup-iats.org/seabreamdb). Six sequences, three categorized as putative membrane-bound mucins and three putative secreted-gel forming mucins, were identified. The transcriptional tissue screening revealed that Muc18 was the predominant mucin in skin, gills and stomach of GSB. In contrast, Muc19 was mostly found in the oesophagus and Muc13 was along the entire intestinal tract, although the posterior intestine exhibited a differential pattern with a high expression of an isoform that does not share a clear orthologous in mammals. This mucin was annotated as intestinal mucin (I-Muc). Its RNA expression was highly regulated by the nutritional background, whereas the other mucins, including Muc2 and Muc2-like, were expressed more constitutively and did not respond to high replacement of fish oil (FO) by vegetable oils (VO) in plant protein-based diets. After challenge with the intestinal parasite Enteromyxum leei, the expression of a number of mucins was decreased mainly in the posterior intestine of infected fish. But, interestingly, the highest down-regulation was observed for the I-Muc. Overall, the magnitude of the changes reflected the intensity and progression of the infection, making mucins and I-Muc, in particular, reliable markers of prognostic and diagnostic value of fish intestinal health. PMID:23776483

  18. Management of the artificial airway.

    PubMed

    Branson, Richard D; Gomaa, Dina; Rodriquez, Dario

    2014-06-01

    Management of the artificial airway includes securing the tube to prevent dislodgement or migration as well as removal of secretions. Preventive measures include adequate humidification and appropriate airway suctioning. Monitoring airway patency and removing obstruction are potentially life-saving components of airway management. Cuff pressure management is important for preventing aspiration and mucosal damage as well as assuring adequate ventilation. A number of new monitoring techniques have been introduced, and automated cuff pressure control is becoming more common. The respiratory therapist should be adept with all these devices and understand the appropriate application and management. PMID:24891202

  19. Kaempferol Inhibits Endoplasmic Reticulum Stress-Associated Mucus Hypersecretion in Airway Epithelial Cells And Ovalbumin-Sensitized Mice

    PubMed Central

    Choi, Yean-Jung; Kang, Min-Kyung; Kim, Yun-Ho; Kang, Young-Hee

    2015-01-01

    Mucus hypersecretion is an important pathological feature of chronic airway diseases, such as asthma and pulmonary diseases. MUC5AC is a major component of the mucus matrix forming family of mucins in the airways. The initiation of endoplasmic reticulum (ER)-mediated stress responses contributes to the pathogenesis of airway diseases. The present study investigated that ER stress was responsible for airway mucus production and this effect was blocked by the flavonoid kaempferol. Oral administration of ≥10 mg/kg kaempferol suppressed mucus secretion and goblet cell hyperplasia observed in the bronchial airway and lung of BALB/c mice sensitized with ovalbumin (OVA). TGF-β and tunicamycin promoted MUC5AC induction after 72 h in human bronchial airway epithelial BEAS-2B cells, which was dampened by 20 μM kaempferol. Kaempferol inhibited tunicamycin-induced ER stress of airway epithelial cells through disturbing the activation of the ER transmembrane sensor ATF6 and IRE1α. Additionally, this compound demoted the induction of ER chaperones such as GRP78 and HSP70 and the splicing of XBP-1 mRNA by tunicamycin. The in vivo study further revealed that kaempferol attenuated the induction of XBP-1 and IRE1α in epithelial tissues of OVA-challenged mice. TGF-β and tunicamycin induced TRAF2 with JNK activation and such induction was deterred by kaempferol. The inhibition of JNK activation encumbered the XBP-1 mRNA splicing and MUC5AC induction by tunicamycin and TGF-β. These results demonstrate that kaempferol alleviated asthmatic mucus hypersecretion through blocking bronchial epithelial ER stress via the inhibition of IRE1α-TRAF2-JNK activation. Therefore, kaempferol may be a potential therapeutic agent targeting mucus hypersecretion-associated pulmonary diseases. PMID:26599511

  20. CFTR, Mucins, and Mucus Obstruction in Cystic Fibrosis

    PubMed Central

    Kreda, Silvia M.; Davis, C. William; Rose, Mary Callaghan

    2012-01-01

    Mucus pathology in cystic fibrosis (CF) has been known for as long as the disease has been recognized and is sometimes called mucoviscidosis. The disease is marked by mucus hyperproduction and plugging in many organs, which are usually most fatal in the airways of CF patients, once the problem of meconium ileus at birth is resolved. After the CF gene, CFTR, was cloned and its protein product identified as a cAMP-regulated Cl− channel, causal mechanisms underlying the strong mucus phenotype of the disease became obscure. Here we focus on mucin genes and polymeric mucin glycoproteins, examining their regulation and potential relationships to a dysfunctional cystic fibrosis transmembrane conductance regulator (CFTR). Detailed examination of CFTR expression in organs and different cell types indicates that changes in CFTR expression do not always correlate with the severity of CF disease or mucus accumulation. Thus, the mucus hyperproduction that typifies CF does not appear to be a direct cause of a defective CFTR but, rather, to be a downstream consequence. In organs like the lung, up-regulation of mucin gene expression by inflammation results from chronic infection; however, in other instances and organs, the inflammation may have a non-infectious origin. The mucus plugging phenotype of the β-subunit of the epithelial Na+ channel (βENaC)-overexpressing mouse is proving to be an archetypal example of this kind of inflammation, with a dehydrated airway surface/concentrated mucus gel apparently providing the inflammatory stimulus. Data indicate that the luminal HCO3 − deficiency recently described for CF epithelia may also provide such a stimulus, perhaps by causing a mal-maturation of mucins as they are released onto luminal surfaces. In any event, the path between CFTR dysfunction and mucus hyperproduction has proven tortuous, and its unraveling continues to offer its own twists and turns, along with fascinating glimpses into biology. PMID:22951447

  1. Management of the Traumatized Airway.

    PubMed

    Jain, Uday; McCunn, Maureen; Smith, Charles E; Pittet, Jean-Francois

    2016-01-01

    There is a lack of evidence-based approach regarding the best practice for airway management in patients with a traumatized airway. General recommendations for the management of the traumatized airway are summarized in table 5. Airway trauma may not be readily apparent, and its evaluation requires a high level of suspicion for airway disruption and compression. For patients with facial trauma, control of the airway may be significantly impacted by edema, bleeding, inability to clear secretions, loss of bony support, and difficulty with face mask ventilation. With the airway compression from neck swelling or hematoma, intubation attempts can further compromise the airway due to expanding hematoma. For patients with airway disruption, the goal is to pass the tube across the injured area without disrupting it or to insert the airway distal to the injury using a surgical approach. If airway injury is extensive, a surgical airway distal to the site of injury may be the best initial approach. Alternatively, if orotracheal intubation is chosen, spontaneous ventilation may be maintained or RSI may be performed. RSI is a common approach. Thus, some of the patients intubated may subsequently require tracheostomy. A stable patient with limited injuries may not require intubation but should be watched carefully for at least several hours. Because of a paucity of evidence-based data, the choice between these approaches and the techniques utilized is a clinical decision depending on the patient's condition, clinical setting, injuries to airway and other organs, and available personnel, expertise, and equipment. Inability to obtain a definitive airway is always an absolute indication for an emergency cricothyroidotomy or surgical tracheostomy. PMID:26517857

  2. Luminal cholinergic signalling in airway lining fluid: a novel mechanism for activating chloride secretion via Ca2+-dependent Cl− and K+ channels

    PubMed Central

    Hollenhorst, Monika I; Lips, Katrin S; Wolff, Miriam; Wess, Jürgen; Gerbig, Stefanie; Takats, Zoltan; Kummer, Wolfgang; Fronius, Martin

    2012-01-01

    BACKGROUND AND PURPOSE Recent studies detected the expression of proteins involved in cholinergic metabolism in airway epithelial cells, although the function of this non-neuronal cholinergic system is not known in detail. Thus, this study focused on the effect of luminal ACh as a regulator of transepithelial ion transport in epithelial cells. EXPERIMENTAL APPROACH RT-PCR experiments were performed using mouse tracheal epithelial cells for ChAT and organic cation transporter (OCT) transcripts. Components of tracheal airway lining fluid were analysed with desorption electrospray ionization (DESI) MS. Effects of nicotine on mouse tracheal epithelial ion transport were examined with Ussing-chamber experiments. KEY RESULTS Transcripts encoding ChAT and OCT1–3 were detected in mouse tracheal epithelial cells. The DESI experiments identified ACh in the airway lining fluid. Luminal ACh induced an immediate, dose-dependent increase in the transepithelial ion current (EC50: 23.3 µM), characterized by a transient peak and sustained plateau current. This response was not affected by the Na+-channel inhibitor amiloride. The Cl−-channel inhibitor niflumic acid or the K+-channel blocker Ba2+ attenuated the ACh effect. The calcium ionophore A23187 mimicked the ACh effect. Luminal nicotine or muscarine increased the ion current. Experiments with receptor gene-deficient animals revealed the participation of muscarinic receptor subtypes M1 and M3. CONCLUSIONS AND IMPLICATIONS The presence of luminal ACh and activation of transepithelial ion currents by luminal ACh receptors identifies a novel non-neuronal cholinergic pathway in the airway lining fluid. This pathway could represent a novel drug target in the airways. PMID:22300281

  3. Expression of ligands for Siglec-8 and Siglec-9 in human airways and airway cells

    PubMed Central

    Jia, Yi; Yu, Huifeng; Fernandes, Steve M.; Wei, Yadong; Gonzalez-Gil, Anabel; Motari, Mary G.; Vajn, Katarina; Stevens, Whitney W.; Peters, Anju T.; Bochner, Bruce S.; Kern, Robert C.; Schleimer, Robert P.; Schnaar, Ronald L.

    2015-01-01

    Background Balanced activation and inhibition of the immune system ensures pathogen clearance while avoiding hyperinflammation. Siglecs, sialic acid binding proteins found on subsets of immune cells, often inhibit inflammation: Siglec-8 on eosinophils and Siglec-9 on neutrophils engage sialoglycan ligands on airways to diminish ongoing inflammation. The identities of human siglec ligands and their expression during inflammation are largely unknown. Objective The histological distribution, expression and molecular characteristics of siglec ligands were explored in healthy and inflamed human upper airways and in a cellular model of airway inflammation. Methods Normal and chronically inflamed upper airway tissues were stained for siglec ligands. The ligands were extracted from normal and inflamed tissues and from human Calu-3 cells for quantitative analysis by siglec blotting and isolation by siglec capture. Results Siglec-8 ligands were expressed on a subpopulation of submucosal gland cells of human inferior turbinate, whereas Siglec-9 ligands were expressed more broadly (submucosal glands, epithelium, connective tissue); both were significantly upregulated in chronic rhinosinusitis patients. Human airway (Calu-3) cells expressed Siglec-9 ligands on mucin 5B under inflammatory control via the NF-κB pathway, and mucin 5B carried sialoglycan ligands of Siglec-9 on human upper airway tissue. Conclusion Inflammation results in upregulation of immune inhibitory Siglec-8 and Siglec-9 sialoglycan ligands on human airways. Siglec-9 ligands were upregulated via the NF-κB pathway resulting in their enhanced expression on mucin 5B. Siglec sialoglycan ligand expression in inflamed cells and tissues may contribute to the control of airway inflammation. PMID:25747723

  4. Production of 3-D Airway Organoids From Primary Human Airway Basal Cells and Their Use in High-Throughput Screening.

    PubMed

    Hild, Marc; Jaffe, Aron B

    2016-01-01

    The ability of human airway basal cells to serve as progenitor cells in the conducting airway makes them an attractive target in a number of respiratory diseases associated with epithelial remodeling. This unit describes a protocol for the culture of 'bronchospheres', three-dimensional (3-D) organoids that are derived from primary human airway basal cells. Mature bronchospheres are composed of functional multi-ciliated cells, mucin-producing goblet cells, and airway basal cells. In contrast to existing methods used for the culture of well-differentiated human airway epithelial cells, bronchospheres do not require growth on a permeable support and can be cultured in 384-well assay plates. The system provides a mechanism for investigating the regulation of basal cell fate during airway epithelial morphogenesis, as well as a basis for studying the function of the human airway epithelium in high-throughput assays. © 2016 by John Wiley & Sons, Inc. PMID:27171795

  5. Effect of copper sulfate upon gill secretory cell nature, mucin production and mucin composition in Mytilus edulis with notes on Modiolus modiolus

    SciTech Connect

    Clements, J.R.

    1983-01-01

    Mussels secrete increased amounts of mucin upon exposure to copper sulfate concentrations equal to or greater than 3 ppm. The threshold level of copper necessary to elicit this response is higher if the animals are exposed to copper sulfate in filtered rather than in unfiltered seawater. At high levels of copper sulfate there is an increase in the relative hydration of the gill tissue.

  6. Transmembrane mucins as novel therapeutic targets

    PubMed Central

    Constantinou, Pamela E; Danysh, Brian P; Dharmaraj, Neeraja; Carson, Daniel D

    2011-01-01

    Membrane-tethered mucin glycoproteins are abundantly expressed at the apical surfaces of simple epithelia, where they play important roles in lubricating and protecting tissues from pathogens and enzymatic attack. Notable examples of these mucins are MUC1, MUC4 and MUC16 (also known as cancer antigen 125). In adenocarcinomas, apical mucin restriction is lost and overall expression is often highly increased. High-level mucin expression protects tumors from killing by the host immune system, as well as by chemotherapeutic agents, and affords protection from apoptosis. Mucin expression can increase as the result of gene duplication and/or in response to hormones, cytokines and growth factors prevalent in the tumor milieu. Rises in the normally low levels of mucin fragments in serum have been used as markers of disease, such as tumor burden, for many years. Currently, several approaches are being examined that target mucins for immunization or nanomedicine using mucin-specific antibodies. PMID:22201009

  7. Surgical Airway

    PubMed Central

    Patel, Sapna A; Meyer, Tanya K

    2014-01-01

    Close to 3% of all intubation attempts are considered difficult airways, for which a plan for a surgical airway should be considered. Our article provides an overview of the different types of surgical airways. This article provides a comprehensive review of the main types of surgical airways, relevant anatomy, necessary equipment, indications and contraindications, preparation and positioning, technique, complications, and tips for management. It is important to remember that the placement of a surgical airway is a lifesaving procedure and should be considered in any setting when one “cannot intubate, cannot ventilate”. PMID:24741501

  8. Induction of IL-6 and inhibition of IL-8 secretion in the human airway cell line Calu-3 by urban particulate matter collected with a modified method of PM sampling

    SciTech Connect

    Alfaro-Moreno, Ernesto; Torres, Victor; Miranda, Javier; Martinez, Leticia; Garcia-Cuellar, Claudia; Nawrot, Tim S.; Vanaudenaerde, Bart; Hoet, Peter; Ramirez-Lopez, Pavel; Rosas, Irma; Nemery, Benoit; Osornio-Vargas, Alvaro Roman

    2009-07-15

    Exposure to particulate matter (PM) induces inflammatory cytokines. In the present study, we evaluated the secretion of IL-6 and IL-8 by an airway cell line exposed to PM with a mean aerodynamic size equal to or less than 10 or 2.5 {mu}m (PM{sub 10} and PM{sub 2.5}, respectively) collected in Mexico City, using a modified high-volume sampling method avoiding the use of solvents or introducing membrane components into the samples. PM was collected on cellulose-nitrate (CN) membranes modified for collection on high-volume samplers. Composition of the particles was evaluated by particle-induced X-ray emission (PIXE) and scanning electron microscopy. The particles (10-160 {mu}g/cm{sup 2}) were tested on Calu-3 cells. Control cultures were exposed to LPS (10 ng/mL to 100 {mu}g/mL) or silica (10-160 {mu}g/cm{sup 2}). IL-6 and IL-8 secretions were evaluated by ELISA. An average of 10 mg of PM was recovered form each cellulose-nitrate filter. No evidence of contamination from the filter was found. Cells exposed to PM{sub 10} presented an increase in the secretion of IL-6 (up to 400%), while IL-8 decreased (from 40% to levels below the detection limit). A similar but weaker effect was observed with PM{sub 2.5}. In conclusion, our modified sampling method provides a large amount of urban PM free of membrane contamination. The urban particles induce a decrease in IL-8 secretion that contrasts with the LPS and silica effects. These results suggest that the regulation of IL-8 expression is different for urban particles (complex mixture containing combustion-related particles, soil and biologic components) than for biogenic compounds or pure mineral particles.

  9. Changes in Saliva Rheological Properties and Mucin Glycosylation in Dry Mouth.

    PubMed

    Chaudhury, N M A; Shirlaw, P; Pramanik, R; Carpenter, G H; Proctor, G B

    2015-12-01

    Saliva is vital for the maintenance of normal oral physiology and mucosal health. The loss of salivary function can have far-reaching consequences, as observed with dry mouth, which is associated with increased orodental disease, speech impairment, dysphagia, and a significant negative effect on quality of life. The timely diagnosis of oral dryness is vital for the management of orodental disease and any associated often-undiagnosed systemic disease (e.g., Sjögren syndrome). Our aim was to investigate differences in mucin glycoproteins and saliva rheological properties between sufferers and nonsufferers of dry mouth in order to understand the relationship between saliva composition, rheological properties, and dryness perception and provide additional potential diagnostic markers. All patients exhibited objective and subjective oral dryness, irrespective of etiology. Over half of the patients (n = 20, 58.8%) had a saliva secretion rate above the gland dysfunction cutoff of 0.1 mL/min. Mucin (MUC5B and MUC7) concentrations were generally similar or higher in patients. Despite the abundance of these moisture-retaining proteins, patients exhibited reduced mucosal hydration (wetness) and significantly lower saliva spinnbarkeit (stringiness), suggesting a loss of the lubricating and retention/adhesion properties of saliva, which, at least partially, are associated with mucin glycoproteins. Over 90% of patients with dry mouth (DMPs) consistently had unstimulated whole mouth saliva (UWMS) spinnbarkeit below the proposed normal cutoff (10 mm). Further analysis of mucins revealed the reduced glycosylation of mucins in DMPs compared to healthy controls. Our data indicate that UWMS mucin concentrations are not reduced in dry mouth but that the mucin structure (glycosylation) is altered. UWMS from DMPs had reduced spinnbarkeit, the assessment of which, in conjunction with sialometry, could improve sensitivity for the diagnosis of dry mouth. Additionally, it may be useful to

  10. Biosynthesis of mucins in bovine trachea: identification of the major radiolabelled species.

    PubMed Central

    Svitacheva, N; Hovenberg, H W; Davies, J R

    1998-01-01

    Bovine trachea in organ culture secretes mucus containing a 'high-density' (1.46 g/ml) and a 'low-density' (1.37 g/ml) mucin similar to those identified previously in bovine respiratory secretions [Hovenberg, Carlstedt and Davies (1997) Biochem. J. 321, 117-123]. After pulse-labelling, autoradiography showed uptake of [35S]sulphate by both epithelial goblet cells and submucosal glands, while [3H]proline was mainly incorporated into the ciliated surface epithelial cells. After 24 h of radiolabelling, neither the high- nor the low-density mucin in the secreted mucus gel was heavily radiolabelled with the precursors. In contrast, a population of molecules banding at 1.50 g/ml was heavily radiolabelled with [35S]sulphate. This component was smaller than the high-density mucin from the mucus gel and was insensitive to reduction or digestion with chondroitin ABC lyase or heparan sulphate lyase. The molecules yielded two populations of high-Mr glycopeptides upon trypsin digestion, were sensitive to keratanase and endo-beta-galactosidase digestion and contained O-linked glycans. Extracts of the surface epithelium and submucosal tissue after radiolabelling showed that the high- and low-density mucins in the tissue were also poorly radiolabelled. Thus, under these conditions, the radiolabelled precursors were not effectively incorporated into the large oligomeric mucins but into a high-Mr monomeric species. This study suggests that data obtained in investigations where mucins are radiolabelled and studied without further separation into distinct components may rather reflect the turnover of this 'novel' monomeric species than the large oligomeric mucins. PMID:9657987

  11. Structure and interactions of human respiratory mucin

    NASA Astrophysics Data System (ADS)

    Purdy, Kirstin; Sheehan, John; Rubinstein, Michael; Wong, Gerard

    2006-03-01

    Human respiratory mucin plays a crucial role in the pathology of Cystic Fibrosis lung infections. Mucin is a flexible, linear polyelectrolyte, characterized by its many charged oligo-carbohydrate side chains that give it its bottle-brush structure. The macroscopic properties of a mucin suspension are known to change drastically with changes in ion concentration and solution pH, but little is known about the effect of these variables on individual mucin structure. We present preliminary results on the structural response of individual human respiratory mucin molecules to variations in concentration of ions of different valences via small angle x-ray diffraction.

  12. Histochemical study of the effects on abomasal mucins of Haemonchus contortus or Teladorsagia circumcincta infection in lambs.

    PubMed

    Simpson, H V; Umair, S; Hoang, V C; Savoian, M S

    2016-08-15

    Previously, chemical analysis of gastric fundic mucin showed that infection of sheep with Haemonchus contortus or Teladorsagia circumcincta changed the proportions of monosaccharides and decreased terminal mucin fucosylation and sialylation. To identify the effects of these parasites on the two mucin-secreting cell lineages, fundic and antral tissues were collected for histochemistry from 69 lambs aged from 3-4 to 9-10 months-of-age which had received a single infection of either H. contortus or T. circumcincta and euthanased at Day 21 or 28 post- infection respectively. All fundic tissues were stained separately with: (1) with Periodic Acid Schiff (PAS) for all mucins; (2) Alcian Blue (AB) pH 2.5 for acidic mucins (sialylated and sulphated); (3) AB pH 1 for sulphated mucins and (4) High Iron Diamine (HID) for sulphated mucins. Antral and fundic tissues from 24 lambs were also stained for acidic and neutral mucins or with specific lectins for α-1-linked fucose and for α-2,3- and α-2,6-linked sialic acids. Only mucin sulphation appeared to differ visually in uninfected lambs over this age range: there was weak staining with HID in tissues from lambs 3-6 months-of-age, but was generally more intense in those over 7 months-of-age. Sulphomucins were not apparent in surface mucous cells (SMC) or generally in the upper pits. Sialylomucins were located predominantly in the pits and glands, with small amounts of sialylated mucins in SMC and on the luminal surface, mainly in younger animals up to 6 months-of-age and less in the older animals. Parasitism markedly reduced the predominantly neutral surface mucin5AC of the SMC and pit cells, despite pit elongation in both antrum and fundus, whereas the acidic Muc6 secreted by mucus neck cells (MNC) increased along with MNC hyperplasia. Sulphated mucins were present mainly from the mid-pits downward and heavy staining was more common in older animals. In these sheep, the markedly reduced neutral mucin in the SMC and pit cells

  13. Transcriptional Activation of Mucin by Pseudomonas aeruginosa Lipopolysaccharide in the Pathogenesis of Cystic Fibrosis Lung Disease

    NASA Astrophysics Data System (ADS)

    Li, Jian-Dong; Dohrman, Austin F.; Gallup, Marianne; Miyata, Susumu; Gum, James R.; Kim, Young S.; Nadel, Jay A.; Prince, Alice; Basbaum, Carol B.

    1997-02-01

    An unresolved question in cystic fibrosis (CF) research is how mutations of the CF transmembrane conductance regulator, a CI ion channel, cause airway mucus obstruction leading to fatal lung disease. Recent evidence has linked the CF transmembrane conductance regulator mutation to the onset and persistence of Pseudomonas aeruginosa infection in the airways, and here we provide evidence directly linking P. aeruginosa infection to mucus overproduction. We show that P. aeruginosa lipopolysaccharide profoundly upregulates transcription of the mucin gene MUC 2 in epithelial cells via inducible enhancer elements and that this effect is blocked by the tyrosine kinase inhibitors genistein and tyrphostin AG 126. These findings improve our understanding of CF pathogenesis and suggest that the attenuation of mucin production by lipopolysaccharide antagonists and tyrosine kinase inhibitors could reduce morbidity and mortality in this disease.

  14. Subcellular localization of KL-6 mucin in intraductal papillary mucinous neoplasm of the pancreas.

    PubMed

    Inagaki, Yoshinori; Seyama, Yasuji; Hasegawa, Kiyoshi; Tang, Wei; Kokudo, Norihiro

    2014-08-01

    This study aimed to clarify the expression profile of KL-6 mucin in intraductal papillary mucinous neoplasm (IPMN) and its relation to tumor malignancy. Expression of KL-6 mucin in 38 IPMNs (intraductal papillary mucinous adenoma (IPMA), 24 cases; minimally invasive intraductal papillary mucinous carcinoma (MI-IPMC), 8 cases; invasive carcinoma originating from IPMC (IC-IPMC), 6 cases) and 66 pancreatic ductal adenocarcinomas (PDACs) was evaluated immunohistochemically. IC-IPMCs and MI-IPMCs had positive staining of KL-6 mucin whereas 58% of IPMAs tested negative. Subcellular localization of KL-6 mucin varied among IPMNs whereas all of the PDAC had positive expression in the circumferential membrane and cytoplasm of cancer cells. IC-IPMCs and MI-IPMCs had a higher frequency of circumferential membrane and cytoplasmic localization of KL-6 mucin than did IPMAs. These results suggest that localization of KL-6 mucin could be used to predict the malignancy of IPMN. PMID:25047009

  15. Chronic effects of mechanical force on airways.

    PubMed

    Tschumperlin, Daniel J; Drazen, Jeffrey M

    2006-01-01

    Airways are embedded in the mechanically dynamic environment of the lung. In utero, this mechanical environment is defined largely by fluid secretion into the developing airway lumen. Clinical, whole lung, and cellular studies demonstrate pivotal roles for mechanical distention in airway morphogenesis and cellular behavior during lung development. In the adult lung, the mechanical environment is defined by a dynamic balance of surface, tissue, and muscle forces. Diseases of the airways modulate both the mechanical stresses to which the airways are exposed as well as the structure and mechanical behavior of the airways. For instance, in asthma, activation of airway smooth muscle abruptly changes the airway size and stress state within the airway wall; asthma also results in profound remodeling of the airway wall. Data now demonstrate that airway epithelial cells, smooth muscle cells, and fibroblasts respond to their mechanical environment. A prominent role has been identified for the epithelium in transducing mechanical stresses, and in both the fetal and mature airways, epithelial cells interact with mesenchymal cells to coordinate remodeling of tissue architecture in response to the mechanical environment. PMID:16460284

  16. Design and expression of a synthetic mucin gene fragment in Escherichia coli.

    PubMed

    Dolby, N; Dombrowski, K E; Wright, S E

    1999-02-01

    Adenocarcinomas of glandular tissues produce a hypoglycosylated form of a normal glycoprotein (mucin) that elicits an immune response. A tumor-specific epitope of mucin occurs in a 20-amino-acid, tandemly repeated domain of human MUC1 mucin. A synthetic gene encoding five tandem repeats of the tumor-specific epitope of human mucin (m5tr) was designed for efficient cloning and expression in Escherichia coli for subsequent use in preparing reagent quantities of the mucin 5 tandem repeat (mtr5) polypeptide. The synthetic gene was cloned in the correct reading frame into the maltose-binding protein (MBP) fusion expression vector pMAL-p2. Bacterial clones containing the mucin synthetic gene (m5tr) were shown to produce the intended recombinant fusion protein, MBP-mtr5. The fusion protein represents a significant fraction of the cell protein, 50% or more of which is secreted into the periplasm. The MBP-mtr5 protein is largely intact and easily prepared in sufficient quantity and purity for preliminary structure-function studies. PMID:10024481

  17. Mucinous cystadenoma of the appendix presenting as an umbilical hernia: A case report

    PubMed Central

    REN, BINGBING; MENG, XIANGCHAO; CAO, ZI; GUO, CHUNLI; ZHANG, ZILI

    2016-01-01

    Mucinous cystadenoma of the appendix is a rare condition that develops as a result of proliferation of mucin-secreting cells in an occluded appendix. Mucinous cystadenoma of the appendix presenting as an umbilical hernia is a rare clinical entity. The most common causes of this condition are known to be ascites, hepatitis and cirrhosis; however, the patient in the present study, was diagnosed as hepatitis- and cirrhosis-negative, with no history of chronic coughing or constipation. The aim of the present study was to report a rare case of mucinous cystadenoma of the appendix presenting as an umbilical hernia in a 66-year-old female patient. The patient had a 6-month history of a reducible mass in the umbilical region and was diagnosed with umbilical hernia. Computed tomography and ultrasonography were performed and revealed massive ascites. Ultimately, a laparoscopic appendectomy was performed and borderline mucinous appendiceal cystadenoma of low malignant potential was confirmed. In addition, the present study discussed the association between mucinous cystadenoma of the appendix and umbilical hernia, as well as the diagnostic process and treatment strategies. PMID:27313766

  18. Ambroxol inhalation ameliorates LPS-induced airway inflammation and mucus secretion through the extracellular signal-regulated kinase 1/2 signaling pathway.

    PubMed

    Zhang, Shui-Juan; Jiang, Juan-Xia; Ren, Qian-Qian; Jia, Yong-Liang; Shen, Jian; Shen, Hui-Juan; Lin, Xi-Xi; Lu, Hong; Xie, Qiang-Min

    2016-03-15

    Ambroxol, a metabolite of bromhexine, is shown to exert several pharmacological activities, including secretolytic, anti-inflammatory and antioxidant actions. Oral and intravenous administration of ambroxol is useful for the airway inflammatory diseases. However, little is known about its potential in inhalation therapy for lipopolysaccharide (LPS)-induced mucous hypersecretion and inflammatory response. In the present study, we compared the pharmacological effects of ambroxol by inhalation with intravenous administration and preliminarily explored its mechanism of action. Our results demonstrated that ambroxol administered by inhalation inhibited MUC5AC expression, reduced glycosaminoglycan levels, enhanced the function of mucociliary clearance and promoted sputum excretion, suggesting that ambroxol increases expectoration of sputum by reducing its viscosity. Moreover, ambroxol significantly alleviated LPS-induced the influx of inflammatory cells and the extracellular signal-regulated kinase 1/2 (Erk 1/2) expression in lung tissues, and inhibited increases in the mRNA expression of the pro-inflammatory cytokines tumor necrosis factor (TNF)-α, CCL-2 (monocyte chemotactic protein-1), KC (keratinocyte cell protein) and interleukin (IL)-1β in lung tissues. The secretolytic and anti-inflammatory effects of inhaled ambroxol at a dose of 7.5mg/ml was comparable to that of ambroxol at 20mg/ml i.v. and dexamethasone at 0.5mg/kg i.p. In addition, we found that ambroxol dose-dependently inhibited LPS-induced increases in the mRNA expression of MUC5AC, TNF-α, and IL-1β in human bronchial epithelial cell (NCI-H292) by inhibiting the Erk signaling pathway. These results demonstrate the beneficial effects of ambroxol in inhalation therapy for the airway inflammatory diseases. PMID:26872986

  19. Tachykinin antagonists and the airways.

    PubMed

    Joos, G F; Kips, J C; Peleman, R A; Pauwels, R A

    1995-01-01

    There is now convincing evidence for the presence of substance P (SP) and neurokinin A (NKA) in human airway nerves. Studies on autopsy tissue, on bronchoalveolar lavage fluid and on sputum suggest that SP may be present in increased amounts in the asthmatic airway. Substance P and NKA are potent bronchoconstrictors of human airways, asthmatics being more sensitive than normal persons. The major enzyme responsible for the degradation of the tachykinins, the neutral endopeptidase, is present in the airways and is involved in the breakdown of exogenously administered SP and NKA, both in normal and asthmatic persons. Other, less well documented airway effects of SP and NKA include mucus secretion, vasodilation and plasma extravasation, as well as the chemoattraction and stimulation of various cells presumed to be involved in asthmatic airway inflammation. NK2 receptors and, to a lesser extent, NK1 receptors have been shown to be involved in bronchoconstriction, whereas NK1 receptors were found to be involved in mucus secretion, microvascular leakage and vasodilatation, and in most of the effects on inflammatory cells. The first clinical trial with FK224, a peptide NK1 and NK2 receptor antagonist, and CP99994, a nonpeptide NK1 receptor antagonist, are negative. However, FK224 failed to block the bronchoconstrictor effect of NKA in asthmatics and the dose of CP99994, needed to antagonize tachykinin effects in man, remains to be determined. PMID:7543746

  20. Mucins and Their Sugars. Critical Mediators of Hyperreactivity and Inflammation.

    PubMed

    Raclawska, Dorota S; Ttofali, Fani; Fletcher, Ashley A; Harper, Daniel N; Bochner, Bruce S; Janssen, William J; Evans, Christopher M

    2016-03-01

    Excessive mucus causes severe airflow obstruction in fatal asthma. It is also present in mild to moderate disease, but is poorly understood and treated. Mucus overproduction is associated with dysregulated expression of the mucins MUC5AC and MUC5B. Whereas increased MUC5AC is a consistent finding, MUC5B varies-remaining stably produced in some patients but strongly repressed in others (>90%). Patients with lower MUC5B display worsened asthma phenotypes including airway hyperreactivity (AHR) to methacholine (MCh) and eosinophilic inflammation. To better understand the roles of mucins in asthma, we generated Muc5ac and Muc5b knockout ((-/-)) mice. AHR to MCh was abolished in antigen-challenged Muc5ac(-/-) mice, due to prevention of heterogeneous mucous plugging that occurred in allergic wild-type mice during MCh-induced bronchoconstriction. Thus, in addition to the established role of smooth muscle-mediated airway narrowing, Muc5ac is an essential noncontractile AHR component. We also found that, unlike Muc5ac(-/-) mice, Muc5b-deficient mice were not protected from asthma phenotypes. Furthermore, whereas inflammation was unaffected by Muc5ac deficiency, it was exaggerated in the absence of Muc5b. On the basis of these differential effects, we are now determining how asthma phenotypes are regulated by mucin isoform specificity. Glycosylation is dramatically different: Muc5ac is heavily fucosylated whereas Muc5b is mainly sialylated. Fucosylation increases mucus viscoelasticity, and FUT2, the enzyme that catalyzes mucin α1,2-fucosylation, is associated with severe asthma exacerbation risk. Sialylation is required for binding to siglec (sialic acid-binding immunoglobulin-like lectin) receptors on leukocytes. Eosinophils express Siglec-F (mouse) or Siglec-8 (human). Engagement by sialoside ligands induces eosinophil apoptosis, and Muc5b via sialylated termini that require the α2,3-sialyltransferase ST3Gal3 for synthesis binds Siglec-F and induces apoptosis in mouse

  1. Polymorphisms in mucin genes in the development of gastric cancer

    PubMed Central

    Wen, Rong; Gao, Fang; Zhou, Cheng-Jiang; Jia, Yan-Bin

    2015-01-01

    Gastric cancer (GC) is the third leading cause of cancer-related death worldwide. In areas of high prevalence, such as Japan, South Korea and China, most cases of GC are related to Helicobacter pylori (H. pylori), which involves well-characterized sequential stages, including infection, atrophic gastritis, intestinal metaplasia, dysplasia, and GC. Mucins are the most abundant high-molecular-weight glycoproteins in mucus, which is the first line of defense and plays a major role in blocking pathogenic factors. Normal gastric mucosa shows expression of MUC1, MUC5AC and MUC6 that is specific to cell type. However, the specific pattern of MUC1, MUC5AC and MUC6 expression is changed in gastric carcinogenesis, accompanied by de novo expression of secreted MUC2. Recent studies have provided evidence that variations in these mucin genes affect many steps of GC development, such as H. pylori infection, and gastric precancerous lesions. In this review, we focus on studies of the association between polymorphisms in mucin genes and development of GC. This information should be helpful for the early detection, surveillance, and treatment of GC. PMID:26600932

  2. REGIONAL DIFFERENCES IN BIOELECTRIC PROPERTIES AND ION FLOW IN EXCISED CANINE AIRWAYS

    EPA Science Inventory

    Absorption of airway liquid, as it moves from the large surface area of distal airways to more central airway surfaces, is considered to be essential for regulation of the depth of airway liquid. The short-circuited excised canine trachea, however, secretes C(-1) and absorbs a le...

  3. Tachykinin receptors and airway pathophysiology.

    PubMed

    Maggi, C A

    1993-05-01

    The mammalian tachykinins (TKs), substance P and neurokinin A, are present in sensory nerve fibres in the upper and lower airways of various mammalian species, including humans. TKs are released from these afferent nerves in an "efferent" mode at peripheral level, especially in response to irritant stimuli. TKs exert a variety of biological effects (bronchoconstriction, plasma protein extravasation, stimulation of mucus secretion), collectively known as "neurogenic inflammation", and this process is thought to be of potential pathogenic relevance for various airway diseases. The recent development of potent and selective TK receptor antagonists on the one hand provides important new tools for the understanding of basic airway physiology and pathophysiology and, on the other, opens new possibilities for therapy of airway diseases. PMID:8390944

  4. Entamoeba histolytica Cysteine Proteinase 5 Evokes Mucin Exocytosis from Colonic Goblet Cells via αvβ3 Integrin

    PubMed Central

    Cornick, Steve; Moreau, France; Chadee, Kris

    2016-01-01

    Critical to the pathogenesis of intestinal amebiasis, Entamoeba histolytica (Eh) induces mucus hypersecretion and degrades the colonic mucus layer at the site of invasion. The parasite component(s) responsible for hypersecretion are poorly defined, as are regulators of mucin secretion within the host. In this study, we have identified the key virulence factor in live Eh that elicits the fast release of mucin by goblets cells as cysteine protease 5 (EhCP5) whereas, modest mucus secretion occurred with secreted soluble EhCP5 and recombinant CP5. Coupling of EhCP5-αvβ3 integrin on goblet cells facilitated outside-in signaling by activating SRC family kinases (SFK) and focal adhesion kinase that resulted in the activation/phosphorlyation of PI3K at the site of Eh contact and production of PIP3. PKCδ was activated at the EhCP5-αvβ3 integrin contact site that specifically regulated mucin secretion though the trafficking vesicle marker myristoylated alanine-rich C-kinase substrate (MARCKS). This study has identified that EhCP5 coupling with goblet cell αvβ3 receptors can initiate a signal cascade involving PI3K, PKCδ and MARCKS to drive mucin secretion from goblet cells critical in disease pathogenesis. PMID:27073869

  5. Entamoeba histolytica Cysteine Proteinase 5 Evokes Mucin Exocytosis from Colonic Goblet Cells via αvβ3 Integrin.

    PubMed

    Cornick, Steve; Moreau, France; Chadee, Kris

    2016-04-01

    Critical to the pathogenesis of intestinal amebiasis, Entamoeba histolytica (Eh) induces mucus hypersecretion and degrades the colonic mucus layer at the site of invasion. The parasite component(s) responsible for hypersecretion are poorly defined, as are regulators of mucin secretion within the host. In this study, we have identified the key virulence factor in live Eh that elicits the fast release of mucin by goblets cells as cysteine protease 5 (EhCP5) whereas, modest mucus secretion occurred with secreted soluble EhCP5 and recombinant CP5. Coupling of EhCP5-αvβ3 integrin on goblet cells facilitated outside-in signaling by activating SRC family kinases (SFK) and focal adhesion kinase that resulted in the activation/phosphorlyation of PI3K at the site of Eh contact and production of PIP3. PKCδ was activated at the EhCP5-αvβ3 integrin contact site that specifically regulated mucin secretion though the trafficking vesicle marker myristoylated alanine-rich C-kinase substrate (MARCKS). This study has identified that EhCP5 coupling with goblet cell αvβ3 receptors can initiate a signal cascade involving PI3K, PKCδ and MARCKS to drive mucin secretion from goblet cells critical in disease pathogenesis. PMID:27073869

  6. Gallbladder inflammation is associated with increase in mucin expression and pigmented stone formation.

    PubMed

    Vilkin, Alexander; Nudelman, Israel; Morgenstern, Sara; Geller, Alex; Bar Dayan, Yosefa; Levi, Zohar; Rodionov, Galina; Hardy, Britta; Konikoff, Fred; Gobbic, Diana; Niv, Yaron

    2007-07-01

    Mucin is a high molecular weight glycoprotein that plays an important role in protecting the gallbladder epithelium from the detergent effect of bile. However, it also participates in gallstone formation. There is little information about a possible relationship between gallbladder inflammation and mucin expression or gallbladder stones' characteristics. The aims of this study were to investigate stone characteristics and patterns of mucin expression in the gallbladder epithelium and bile of gallstone patients, in relation to inflammation. Gallbladder bile and tissue samples from 21 patients were obtained at surgery. Mucin content was evaluated by gel filtration on a Sepharose CL-4B column. Dot blot for bile mucin apoproteins and immunohistochemistry staining for gallbladder mucosal mucin apoproteins were performed with antibodies to MUC2, MUC3, MUC5AC, MUC5B and MUC6. Staining intensity score (0-3) was used for assessment of antigen expression and the level of inflammation. Gallstone cholesterol content was determined in 16 patients. MUC 5AC and MUC 5B were demonstrated in 95.4 and 100% of gallbladder bile samples, respectively. Immunohistochemistry staining with antibodies to MUC 2, MUC 3, MUC 5AC, MUC 5B and MUC 6 were positive in 0, 100, 85.7, 100 and 95.4% of the gallbladder mucosal samples, respectively. Pigmented brown stones were associated with a higher level of gallbladder inflammation. Mucin species expressed in gallbladder epithelium are MUC3, MUC5AC, MUC5B and MUC6. MUC5AC and MUC5B are secreted into bile. Inflammation of the gallbladder is accompanied by a higher level of MUC5AC expression and is associated with pigmented brown stones. PMID:17385041

  7. Current status of mucins in the diagnosis and therapy of cancer

    PubMed Central

    Rachagani, Satyanarayana; Torres, Maria P.; Moniaux, Nicolas; Batra, Surinder K.

    2010-01-01

    Mucins are the most abundant high molecular weight glycoproteins in mucus. Their nature and glycosylation content dictates the biochemical and biophysical properties of viscoelastic secretions, pointing out an important role in diverse biological functions, such as differentiation, cell adhesions, immune responses, and cell signaling. Mucins are expressed in tubular organs by specialized epithelial cells in the body. Their aberrant expression is well documented in a variety of inflammatory or malignant diseases. From a prognosis point of view, their expression and alterations in glycosylation are associated with the development and progression of malignant diseases. Therefore, mucins can be used as valuable markers to distinguish between normal and disease conditions. Indeed, this alteration in glycosylation patterns generates several epitopes in the oligosaccharide side chains that can be used as diagnostic and/or prognostic markers. Furthermore, these characteristic tumor-associated epitopes are extensively used as appropriate immunotargets of malignant epithelial cells. Therefore, in an effort to detect and treat cancer at the earliest stage possible, mucins are analyzed as potential markers of disease for diagnosis, progression, and for therapeutic purposes. In this review, we focused on the current status of the distribution of mucins in normal and pathologic conditions and their clinical use both in cancer diagnosis and therapeutics treatments. PMID:19904814

  8. Mucins in pancreatic cancer and its microenvironment

    PubMed Central

    Kaur, Sukhwinder; Kumar, Sushil; Momi, Navneet; Sasson, Aaron R.; Batra, Surinder K.

    2014-01-01

    Pancreatic cancer remains a lethal malignancy with poor prognosis owing to therapeutic resistance, frequent recurrence and the absence of treatment strategies that specifically target the tumour and its supporting stroma. Deregulated cell-surface proteins drive neoplastic transformations and are envisioned to mediate crosstalk between the tumour and its microenvironment. Emerging studies have elaborated on the role of mucins in diverse biological functions, including enhanced tumorigenicity, invasiveness, metastasis and drug resistance through their characteristic O-linked and N-linked oligosaccharides (glycans), extended structures and unique domains. Multiple mucin domains differentially interact and regulate different components of the tumour microenvironment. This Review discusses: the expression pattern of various mucins in the pancreas under healthy, inflammatory, and cancerous conditions; the context-dependent attributes of mucins that differ under healthy and pathological conditions; the contribution of the tumour microenvironment in pancreatic cancer development and/or progression; diagnostic and/or prognostic efficacy of mucins; and mucin-based therapeutic strategies. Overall, this information should help to delineate the intricacies of pancreatic cancer by exploring the family of mucins, which, through various mechanisms in both tumour cells and the microenvironment, worsen disease outcome. PMID:23856888

  9. Biomimetic oral mucin from polymer micelle networks

    NASA Astrophysics Data System (ADS)

    Authimoolam, Sundar Prasanth

    Mucin networks are formed by the complexation of bottlebrush-like mucin glycoprotein with other small molecule glycoproteins. These glycoproteins create nanoscale strands that then arrange into a nanoporous mesh. These networks play an important role in ensuring surface hydration, lubricity and barrier protection. In order to understand the functional behavior in mucin networks, it is important to decouple their chemical and physical effects responsible for generating the fundamental property-function relationship. To achieve this goal, we propose to develop a synthetic biomimetic mucin using a layer-by-layer (LBL) deposition approach. In this work, a hierarchical 3-dimensional structures resembling natural mucin networks was generated using affinity-based interactions on synthetic and biological surfaces. Unlike conventional polyelectrolyte-based LBL methods, pre-assembled biotin-functionalized filamentous (worm-like) micelles was utilized as the network building block, which from complementary additions of streptavidin generated synthetic networks of desired thickness. The biomimetic nature in those synthetic networks are studied by evaluating its structural and bio-functional properties. Structurally, synthetic networks formed a nanoporous mesh. The networks demonstrated excellent surface hydration property and were able capable of microbial capture. Those functional properties are akin to that of natural mucin networks. Further, the role of synthetic mucin as a drug delivery vehicle, capable of providing localized and tunable release was demonstrated. By incorporating antibacterial curcumin drug loading within synthetic networks, bacterial growth inhibition was also demonstrated. Thus, such bioactive interfaces can serve as a model for independently characterizing mucin network properties and through its role as a drug carrier vehicle it presents exciting future opportunities for localized drug delivery, in regenerative applications and as bio

  10. Airway acidification initiates host defense abnormalities in cystic fibrosis mice

    PubMed Central

    Shah, Viral S.; Meyerholz, David K.; Tang, Xiao Xiao; Reznikov, Leah; Alaiwa, Mahmoud Abou; Ernst, Sarah E.; Karp, Philip H.; Wohlford-Lenane, Christine L.; Heilmann, Kristopher P.; Leidinger, Mariah R.; Allen, Patrick D.; Zabner, Joseph; McCray, Paul B.; Ostedgaard, Lynda S.; Stoltz, David A.; Randak, Christoph O.; Welsh, Michael J.

    2016-01-01

    Cystic fibrosis (CF) is caused by mutations in the gene that encodes the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel. In humans and pigs, the loss of CFTR impairs respiratory host defenses, causing airway infection. But CF mice are spared. We found that in all three species, CFTR secreted bicarbonate into airway surface liquid. In humans and pigs lacking CFTR, unchecked H+ secretion by the nongastric H+/K+ adenosine triphosphatase (ATP12A) acidified airway surface liquid, which impaired airway host defenses. In contrast, mouse airways expressed little ATP12A and secreted minimal H+; consequently, airway surface liquid in CF and non-CF mice had similar pH. Inhibiting ATP12A reversed host defense abnormalities in human and pig airways. Conversely, expressing ATP12A in CF mouse airways acidified airway surface liquid, impaired defenses, and increased airway bacteria. These findings help explain why CF mice are protected from infection and nominate ATP12A as a potential therapeutic target for CF. PMID:26823428

  11. Airway acidification initiates host defense abnormalities in cystic fibrosis mice.

    PubMed

    Shah, Viral S; Meyerholz, David K; Tang, Xiao Xiao; Reznikov, Leah; Abou Alaiwa, Mahmoud; Ernst, Sarah E; Karp, Philip H; Wohlford-Lenane, Christine L; Heilmann, Kristopher P; Leidinger, Mariah R; Allen, Patrick D; Zabner, Joseph; McCray, Paul B; Ostedgaard, Lynda S; Stoltz, David A; Randak, Christoph O; Welsh, Michael J

    2016-01-29

    Cystic fibrosis (CF) is caused by mutations in the gene that encodes the cystic fibrosis transmembrane conductance regulator (CFTR) anion channel. In humans and pigs, the loss of CFTR impairs respiratory host defenses, causing airway infection. But CF mice are spared. We found that in all three species, CFTR secreted bicarbonate into airway surface liquid. In humans and pigs lacking CFTR, unchecked H(+) secretion by the nongastric H(+)/K(+) adenosine triphosphatase (ATP12A) acidified airway surface liquid, which impaired airway host defenses. In contrast, mouse airways expressed little ATP12A and secreted minimal H(+); consequently, airway surface liquid in CF and non-CF mice had similar pH. Inhibiting ATP12A reversed host defense abnormalities in human and pig airways. Conversely, expressing ATP12A in CF mouse airways acidified airway surface liquid, impaired defenses, and increased airway bacteria. These findings help explain why CF mice are protected from infection and nominate ATP12A as a potential therapeutic target for CF. PMID:26823428

  12. Regulation of human airway surface liquid.

    PubMed

    Widdicombe, J H; Widdicombe, J G

    1995-01-01

    Human airways are lined with a film of liquid from 5-100 microns in depth, consisting of a periciliary sol around and a mucous gel above the cilia. Microscopical studies have shown the sol to be invariably the same depth as the length of the cilia, and we discuss possible reasons for this. The composition and sources of the airway surface liquid are also described. In addition the forces regulating its volume are analyzed. Several airway diseases are characterised by dramatic changes in the volume and composition of airway liquid. We review recent research suggesting that the accumulation of airway mucous secretions in cystic fibrosis is caused by alterations in active transport of ions and water across both the surface and gland epithelia. PMID:7740210

  13. Identification of Differentially Expressed miRNAs in Appendiceal Mucinous Cystadenocarcinoma from Mucinous Cystadenoma

    PubMed Central

    Wu, Richard Licheng; Ali, Shadan; Sarkar, Fazlul H; Beydoun, Rafic

    2016-01-01

    Objective Mucinous cystadenocarcinoma of appendix is a rare entity. Differentiating mucinous cystadenocarcinoma from mucinous cystadenoma is very challenging and depends on establishing the presence of malignant cells in the appendix wall. The invasion may be very difficult to assess in some cases, especially in early stages of the disease, which could have devastating prognostic effects on patients. Therefore, it is necessary to develop an ancillary test that can differentiate the mucinous cystadenocarcinoma from mucinous cystadenoma. So far, there is no report available about the role of differentially expressed miRNAs in the diagnosis of appendiceal mucinous cystadenocarcinoma. Materials and Methods Six confirmed mucinous appendiceal cystadenocarcinoma and twelve mucinous appendiceal cystadenoma cases were selected. The total RNAs were extracted from the formalin-fixed paraffin-embedded specimen of these cases. The comprehensive miRNA microarray expression profiling from pooled aliquots of RNA samples from these two entities were analyzed to detect the differentially expressed miRNAs in mucinous cystadenocarcinoma. The best seven differentially expressed miRNAs were validated in individual cases by quantitative reverse transcriptase PCR (qRT-PCR). Results The microarray miRNA expression profiling analysis revealed 646 miRNAs that were differentially expressed in the mucinous cystadenocarcinoma. Among these differentially expressed miRNAs, the expression of 80 miRNAs showed statistical difference (p<0.01). The quantitative RT-PCR validated that the expression of miR-1, miR-4328 was significantly down regulated in mucinous cystadenocarcinoma compared to the mucinous cystadenoma (p<0.05). On the other hand, the expression of miR-200b, miR-200c, miR-451, miR-223 and miR-21 were significantly upregulated in mucinous cystadenocarcinoma (p<0.05). Conclusion The expression levels of miRNAs tested were significantly altered in the appendiceal mucinous cystadenocarcinoma

  14. Mucinous Urothelial Carcinoma of the Renal Pelvis

    PubMed Central

    Behzatğlu, Kemal; Boyaci, Ceren; Okçu, Oğuzhan; Hacihasanoğlu, Ezgi; Çakir, Yasemin; Darakçi, Seher

    2014-01-01

    Urothelial carcinoma with abundant myxoid stroma is a newly-described and extremely rare entity. Since only very few cases have been reported, there is no consensus on its nomenclature. Microscopic examination revealed invasive urothelial carcinoma with widespread low-grade noninvasive areas. There were focal invasive areas in the neighborhood of the renal parenchyma. Malignant urothelial tumor/cell groups localized in the stroma had abundant myxoid/mucinous background in the invasive areas. The cytoplasm of the tumoral cells was more eosinophilic in these areas and the cells formed small groups and cords. Histochemically, PAS and Alcian Blue were positive in the cytoplasm of the tumoral cells and in the stroma while negative in the non-mucinous areas. Immunohistochemically, the tumoral cells of the mucinous invasive areas diffusely expressed MUC1 and MUC2. We discuss the origin of the mucinous/myxoid stroma, the tumor’s nature and its nomenclature with histochemical and immunohistochemical features. PMID:25568745

  15. Airway Surface Mycosis in Chronic Th2-Associated Airway Disease

    PubMed Central

    Porter, Paul; Lim, Dae Jun; Maskatia, Zahida Khan; Mak, Garbo; Tsai, Chu-Lin; Citardi, Martin J; Fakhri, Samer; Shaw, Joanne L.; Fothergil, Annette; Kheradmand, Farrah; Corry, David B; Luong, Amber

    2014-01-01

    Background Environmental fungi have been linked to T helper type 2 (Th2) cell-related airway inflammation and the Th2-associated chronic airway diseases asthma, chronic rhinosinusitis with nasal polyps (CRSwNP) and allergic fungal rhinosinusitis (AFRS), but whether these organisms participate directly or indirectly in disease pathology remains unknown. Objective To determine the frequency of fungus isolation and fungus-specific immunity in Th2-associated and non-associated airway disease patients. Methods Sinus lavage fluid and blood were collected from sinus surgery patients (n=118) including CRS patients with and without nasal polyps and AFRS and non-CRS/non-asthmatic control patients. Asthma status was deteremined from medical history. Sinus lavage fluids were cultured and directly examined for evidence of viable fungi. Peripheral blood mononuclear cells were restimulated with fungal antigens in an enzyme linked immunocell spot (ELISpot) assay to determine total memory fungus-specific IL-4-secreting cells. These data were compared to fungus-specific IgE levels measured from plasma by ELISA. Results Filamentous fungi were significantly more commonly cultured from Th2-associated airway disease subjects (asthma, CRSwNP, or AFRS: n=68) compared to non-Th2-associated control patients (n=31); 74% vs 16% respectively, p<0.001. Both fungus-specific IL-4 ELISpot (n=48) and specific IgE (n=70) data correlated with Th2-associated diseases (sensitivity 73% and specificity 100% vs. 50% and 77%, respectively). Conclusions The frequent isolation of fungi growing directly within the airways accompanied by specific immunity to these organisms only in patients with Th2-associated chronic airway diseases suggests that fungi participate directly in the pathogenesis of these conditions. Efforts to eradicate airway fungi from the airways should be considered in selected patients. Clinical Implications Airway fungi may contribute to the expression of sinusitis with nasal polyps and

  16. Mouse gastric mucin: cloning and chromosomal localization.

    PubMed Central

    Shekels, L L; Lyftogt, C; Kieliszewski, M; Filie, J D; Kozak, C A; Ho, S B

    1995-01-01

    Mucins protect gastric epithelium by maintaining a favourable pH gradient and preventing autodigestion. The purpose of this study was to clone a mouse gastric mucin which would provide a foundation for analysis of mucin gene regulation. Mucin was purified from the glandular portion of gastric specimens and deglycosylated by HF solvolysis. Antibodies against native and deglycosylated mouse gastric mucin (MGM) were raised in chickens. Screening of a mouse stomach cDNA library with the anti-(deglycosylated MGM) antibody yielded partial clones containing a 48 bp tandem repeat and 768 bp of non-repetitive sequence. The 16-amino-acid tandem repeat has a consensus sequence of QTSSPNTGKTSTISTT with 25% serine and 38% threonine. The MGM tandem repeat sequence bears no similarity to previously identified mucins. The MGM non-repetitive region shares sequence similarity with human MUC5AC and, to a lesser extent, human MUC2 and rat intestinal mucin. Northern blot analysis reveals a polydisperse message beginning at 13.5 kb in mouse stomach with no expression in oesophagus, trachea, small intestine, large intestine, caecum, lung or kidney. Immunoreactivity of antibodies against deglycosylated MGM and against a synthetic MGM tandem repeat peptide was restricted to superficial mucous cells, antral glands and Brunner's glands in the pyloric-duodenal region. DNA analysis shows that MGM recognizes mouse and rat DNA but not hamster, rabbit or human DNA. The MGM gene maps to a site on mouse chromosome 7 homologous to the location of a human secretory mucin gene cluster on human chromosome 11p15. Due to sequence similarity and predominant expression in the stomach, the MGM gene may be considered a MUC5AC homologue and named Muc5ac. Images Figure 1 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 PMID:7487932

  17. Muc5ac Mucin Expression During Rat Skin Development

    PubMed Central

    Ferretti, V.; Segal-Eiras, A.; Barbeito, C.G.; Croce, M.V.

    2015-01-01

    Some mucin genes have been detected during human embryonic and fetal organ development; however, little is known about mucin expression in epidermal development, neither in humans nor in other species. The present research was developed to explore Muc5ac skin expression during pre- and post-natal rat development. Immunohistochemistry (IHC), Western blotting (WB) and RT-PCR were employed. By IHC, Muc5ac protein was found early in embryonic epidermis from day 13 of gestation until seven days after birth when the surface epidermis became negative and the reaction was restricted to secreting sebum cells. In coincidence with IHC findings, WB analysis showed a band at approximately 200KDa at the same periods of development. Results were also confirmed by RT-PCR. Muc5ac expression in rat embryonic epidermis suggests that Muc5ac may play a protective role in embryonic skin previous to birth which may be replaced by pile covering. To our knowledge, this is the first report that confirmed Muc5ac expression during skin development. PMID:25820562

  18. Effect of Dietary Exogenous Enzyme Supplementation on Enteric Mucosal Morphological Development and Adherent Mucin Thickness in Turkeys

    PubMed Central

    Ayoola, Ayuub A.; Malheiros, Ramon D.; Grimes, Jesse L.; Ferket, Peter R.

    2015-01-01

    Anti-nutritional factors (ANFs) in feed ingredients can challenge gut health and reduce nutrient utilization. Birds typically activate their innate immune system as a protective response against the adverse effects of ANF, which often involves the secretion of mucin. Although dietary supplementation of exogenous enzymes are commonly used to alleviate the adverse effects of ANF on apparent nutrient digestibility, little is known about how they affect gut health, particularly in relation to the morphological development and mucin secretion of enteric mucosa. We carried out two trials to examine the effect of dietary supplementation of different types of exogenous enzymes on gut health of by accessing the effect of jejunum morphological development and ileal enteric adherent mucin thickness layer in turkeys. Dietary β-mannanase supplementation reduced ileal adherent mucin thickness layer (804 vs 823 μg/g; p < 0.05), while a commercial blend of xylanase, amylase, and protease (XAP) reduced ileal adherent mucin layer thickness (589 vs 740 μg/g; p < 0.05); thus reducing the apparent endogenous loss of nutrients. Both enzyme supplements also affected gut morphological characteristics. In comparison to the control treatment, dietary β-mannanase supplementation improved the jejunum tip width (219 vs 161; p < 0.05), base width (367 vs 300; p < 0.05), surface area (509,870 vs 380, 157; p < 0.05) and villi height/crypt depth ratio (7.49 vs 5.70; p < 0.05), and XAP improved the crypt depth (p < 0.05). In conclusion, dietary supplementation of exogenous enzymes may help alleviate the adverse effects of ANF on nutrient utilization by directly or indirectly removing the mucosal irritation that stimulates enteric mucin secretion. PMID:26664972

  19. Emergency airway puncture

    MedlinePlus

    Emergency airway puncture is the placement of a hollow needle through the throat into the airway. It ... Emergency airway puncture is done in an emergency situation, when someone is choking and all other efforts ...

  20. Mucin-Microbiota Interaction During Postnatal Maturation of the Intestinal Ecosystem: Clinical Implications.

    PubMed

    Rokhsefat, Sana; Lin, Aifeng; Comelli, Elena M

    2016-06-01

    The mucus layer and gut microbiota interplay contributes to host homeostasis. The mucus layer serves as a scaffold and a carbon source for gut microorganisms; conversely, gut microorganisms, including mucin degraders, influence mucin gene expression, glycosylation, and secretion. Conjointly they shield the epithelium from luminal pathogens, antigens, and toxins. Importantly, the mucus layer and gut microbiota are established in parallel during early postnatal life. During this period, the development of gut microbiota and mucus layer is coupled with that of the immune system. Developmental changes of different mucin types can impact the age-dependent patterns of intestinal infection in terms of incidence and severity. Altered mucus layer, dysbiotic microbiota, and abnormal mucus-gut microbiota interaction have the potential for inducing systemic effects, and accompany several intestinal diseases such as inflammatory bowel disease, colorectal cancer, and radiation-induced mucositis. Early life provides a pivotal window of opportunity to favorably modulate the mucus-microbiota interaction. The support of a health-compatible mucin-microbiota maturation in early life is paramount for long-term health and serves as an important opportunity for clinical intervention. PMID:26792279

  1. Increased Understanding of the Biochemistry and Biosynthesis of MUC2 and Other Gel-Forming Mucins Through the Recombinant Expression of Their Protein Domains

    PubMed Central

    Ambort, Daniel; Thomsson, Elisabeth; Johansson, Malin E. V.; Hansson, Gunnar C.

    2016-01-01

    The gel-forming mucins are large and heavily O-glycosylated proteins which build up mucus gels. The recombinant production of full-length gel-forming mucins has not been possible to date. In order to study mucin biosynthesis and biochemistry, we and others have taken the alternative approach of constructing different recombinant proteins consisting of one or several domains of these large proteins and expressing them separately in different cell lines. Using this approach, we have determined that MUC2, the intestinal gel-forming mucin, dimerizes via its C-terminal cysteine-knot domain and also trimerizes via one of the N-terminal von Willebrand D domains. Both of these interactions are disulfide bond mediated. Via this assembly, a molecular network is built by which the mucus gel is formed. Here we discuss not only the functional understanding obtained from studies of the recombinant proteins, but also highlight the difficulties encountered when these proteins were produced recombinantly. We often found an accumulation of the proteins in the ER and consequently no secretion. This was especially apparent when the cysteine-rich domains of the N- and C-terminal parts of the mucins were expressed. Other proteins that we constructed were either not secreted or not expressed at all. Despite these problems, the knowledge of mucin biosynthesis and assembly has advanced considerably through the studies of these recombinant proteins. PMID:23359125

  2. Blockage of upper airway

    MedlinePlus

    ... Airway obstruction - acute upper Images Throat anatomy Choking Respiratory system References Cukor J, Manno M. Pediatric respiratory emergencies: upper airway obstruction and infections. In: Marx ...

  3. EGFR Interacts with the Fusion Protein of Respiratory Syncytial Virus Strain 2-20 and Mediates Infection and Mucin Expression

    PubMed Central

    Stobart, Christopher C.; Hotard, Anne L.; Villenave, Remi; Meng, Jia; Pretto, Carla D.; Shields, Michael D.; Nguyen, Minh Trang; Todd, Sean O.; Chi, Michael H.; Hammonds, Jason; Krumm, Stefanie A.; Spearman, Paul; Plemper, Richard K.; Sakamoto, Kaori; Peebles, R. Stokes; Power, Ultan F.; Moore, Martin L.

    2016-01-01

    Respiratory syncytial virus (RSV) is the major cause of viral lower respiratory tract illness in children. In contrast to the RSV prototypic strain A2, clinical isolate RSV 2–20 induces airway mucin expression in mice, a clinically relevant phenotype dependent on the fusion (F) protein of the RSV strain. Epidermal growth factor receptor (EGFR) plays a role in airway mucin expression in other systems; therefore, we hypothesized that the RSV 2–20 F protein stimulates EGFR signaling. Infection of cells with chimeric strains RSV A2-2-20F and A2-2-20GF or over-expression of 2–20 F protein resulted in greater phosphorylation of EGFR than infection with RSV A2 or over-expression of A2 F, respectively. Chemical inhibition of EGFR signaling or knockdown of EGFR resulted in diminished infectivity of RSV A2-2-20F but not RSV A2. Over-expression of EGFR enhanced the fusion activity of 2–20 F protein in trans. EGFR co-immunoprecipitated most efficiently with RSV F proteins derived from “mucogenic” strains. RSV 2–20 F and EGFR co-localized in H292 cells, and A2-2-20GF-induced MUC5AC expression was ablated by EGFR inhibitors in these cells. Treatment of BALB/c mice with the EGFR inhibitor erlotinib significantly reduced the amount of RSV A2-2-20F-induced airway mucin expression. Our results demonstrate that RSV F interacts with EGFR in a strain-specific manner, EGFR is a co-factor for infection, and EGFR plays a role in RSV-induced mucin expression, suggesting EGFR is a potential target for RSV disease. PMID:27152417

  4. Intraductal Papillary Mucinous Neoplasm of Pancreas

    PubMed Central

    Machado, Norman Oneil; al Qadhi, Hani; al Wahibi, Khalifa

    2015-01-01

    Intraductal papillary mucinous neoplasms (IPMNs) of the pancreas are neoplasms that are characterized by ductal dilation, intraductal papillary growth, and thick mucus secretion. This relatively recently defined pathology is evolving in terms of its etiopathogenesis, clinical features, diagnosis, management, and treatment guidelines. A PubMed database search was performed. All the relevant abstracts in English language were reviewed and the articles in which cases of IPMN could be identified were further scrutinized. Information of IPMN was derived, and duplication of information in several articles and those with areas of persisting uncertainties were excluded. The recent consensus guidelines were examined. The reported incidence of malignancy varies from 57% to 92% in the main duct-IPMN (MD-IPMN) and from 6% to 46% in the branch duct-IPMN (BD-IPMN). The features of high-risk malignant lesions that raise concern include obstructive jaundice in a patient with a cystic lesion in the pancreatic head, the findings on radiological imaging of a mass lesion of >30 mm, enhanced solid component, and the main pancreatic duct (MPD) of size ≥10 mm; while duct size 5-9 mm and cyst size <3 mm are considered as “worrisome features.” Magnetic resonance imaging (MRI) and endoscopic ultrasound (EUS) are primary investigations in diagnosing and following up on these patients. The role of pancreatoscopy and the analysis of aspirated cystic fluid for cytology and DNA analysis is still to be established. In general, resection is recommended for most MD-IPMN, mixed variant, and symptomatic BD-IPMN. The 5-year survival of patients after surgical resection for noninvasive IPMN is reported to be at 77-100%, while for those with invasive carcinoma, it is significantly lower at 27-60%. The follow-up of these patients could vary from 6 months to 1 year and would depend on the risk stratification for invasive malignancy and the pathology of the resected specimen. The understanding of

  5. Role of platelets in allergic airway inflammation.

    PubMed

    Idzko, Marco; Pitchford, Simon; Page, Clive

    2015-06-01

    Increasing evidence suggests an important role for platelets and their products (e.g., platelet factor 4, β-thromboglobulin, RANTES, thromboxane, or serotonin) in the pathogenesis of allergic diseases. A variety of changes in platelet function have been observed in patients with asthma, such as alterations in platelet secretion, expression of surface molecules, aggregation, and adhesion. Moreover, platelets have been found to actively contribute to most of the characteristic features of asthma, including bronchial hyperresponsiveness, bronchoconstriction, airway inflammation, and airway remodeling. This review brings together the current available data from both experimental and clinical studies that have investigated the role of platelets in allergic airway inflammation and asthma. It is anticipated that a better understanding of the role of platelets in the pathogenesis of asthma might lead to novel promising therapeutic approaches in the treatment of allergic airway diseases. PMID:26051948

  6. Mucinous borderline ovarian tumor with ascites.

    PubMed

    Batool, Tahira; Ullah, Nasreen Rehmat

    2014-11-01

    Borderline mucinous tumors are epithelial ovarian tumors with low rate of growth and low potential to invade or metastasize and associated with significantly better prognosis and excellent disease-free survival after surgical removal than other epithelial ovarian cancers. The accepted initial treatment is surgical removal of the tumor. Fertility-sparing surgery may suffice in young patients with tumors confined to the ovary. Radical surgery is recommended in patients with advanced disease and advanced age. Long-term surveillance is recommended to document and treat late recurrences. We report a case of a 59 years old postmenopausal patient with complex ovarian mucinous tumor and gross ascites; she had received three lines of chemotherapeutic agents pre-operatively, without any favorable outcome. Then, she went for staging laparotomy and histopathology showed borderline ovarian mucinous tumor required no further treatment and is fine till date. PMID:25518783

  7. Inhibition of airway surface fluid absorption by cholinergic stimulation

    PubMed Central

    Joo, Nam Soo; Krouse, Mauri E.; Choi, Jae Young; Cho, Hyung-Ju; Wine, Jeffrey J.

    2016-01-01

    In upper airways airway surface liquid (ASL) depth and clearance rates are both increased by fluid secretion. Secretion is opposed by fluid absorption, mainly via the epithelial sodium channel, ENaC. In static systems, increased fluid depth activates ENaC and decreased depth inhibits it, suggesting that secretion indirectly activates ENaC to reduce ASL depth. We propose an alternate mechanism in which cholinergic input, which causes copious airway gland secretion, also inhibits ENaC-mediated absorption. The conjoint action accelerates clearance, and the increased transport of mucus out of the airways restores ASL depth while cleansing the airways. We were intrigued by early reports of cholinergic inhibition of absorption by airways in some species. To reinvestigate this phenomenon, we studied inward short-circuit currents (Isc) in tracheal mucosa from human, sheep, pig, ferret, and rabbit and in two types of cultured cells. Basal Isc was inhibited 20–70% by the ENaC inhibitor, benzamil. Long-lasting inhibition of ENaC-dependent Isc was also produced by basolateral carbachol in all preparations except rabbit and the H441 cell line. Atropine inhibition produced a slow recovery or prevented inhibition if added before carbachol. The mechanism for inhibition was not determined and is most likely multi-factorial. However, its physiological significance is expected to be increased mucus clearance rates in cholinergically stimulated airways. PMID:26846701

  8. Inhibition of airway surface fluid absorption by cholinergic stimulation.

    PubMed

    Joo, Nam Soo; Krouse, Mauri E; Choi, Jae Young; Cho, Hyung-Ju; Wine, Jeffrey J

    2016-01-01

    In upper airways airway surface liquid (ASL) depth and clearance rates are both increased by fluid secretion. Secretion is opposed by fluid absorption, mainly via the epithelial sodium channel, ENaC. In static systems, increased fluid depth activates ENaC and decreased depth inhibits it, suggesting that secretion indirectly activates ENaC to reduce ASL depth. We propose an alternate mechanism in which cholinergic input, which causes copious airway gland secretion, also inhibits ENaC-mediated absorption. The conjoint action accelerates clearance, and the increased transport of mucus out of the airways restores ASL depth while cleansing the airways. We were intrigued by early reports of cholinergic inhibition of absorption by airways in some species. To reinvestigate this phenomenon, we studied inward short-circuit currents (Isc) in tracheal mucosa from human, sheep, pig, ferret, and rabbit and in two types of cultured cells. Basal Isc was inhibited 20-70% by the ENaC inhibitor, benzamil. Long-lasting inhibition of ENaC-dependent Isc was also produced by basolateral carbachol in all preparations except rabbit and the H441 cell line. Atropine inhibition produced a slow recovery or prevented inhibition if added before carbachol. The mechanism for inhibition was not determined and is most likely multi-factorial. However, its physiological significance is expected to be increased mucus clearance rates in cholinergically stimulated airways. PMID:26846701

  9. In vitro utilization of mucin by Bacteroides fragilis.

    PubMed Central

    Roberton, A M; Stanley, R A

    1982-01-01

    A method for isolating pig colon mucin in a soluble high-molecular-weight form, suitable for addition to bacterial growth media, is described. This preparation was utilized as a sole carbohydrate energy source by two strains of Bacteroides fragilis. The extent of degradation was compared with that of commercial pig gastric mucin by the same strains. Gas-liquid chromatographic analysis of the mucin carbohydrates and gel chromatography of the preparations were carried out before and after in vitro degradation. The mucin carbohydrates were utilized only to a very limited extent, colon mucin being more resistant to degradation than gastric mucin. Both mucins chromatographed at or near the excluded volume on Sepharose 4B, and only in the case of ATCC 25285 grown on gastric mucin was a significant degradation peak detected. If mucins are degraded in vivo by the sequential action of several bacteria, a pure culture in vitro might be expected to degrade mucins to a limited extent only. Techniques previously used to examine mucin utilization by pure cultures may have overlooked limited mucin degradation demonstrated by the methods used in this work. PMID:6174077

  10. Mucinous Balls Tangled With Mesothelial Cells and MUC2-Positive Cancer Cells in the Ascites of Pseudomyxoma Peritonei.

    PubMed

    Akashi, Shizuka; Kuwabara, Hiroko; Yasuda, Emi; Akutagawa, Hiroshi; Takeshita, Atsushi; Kurisu, Yoshitaka; Egashira, Yutaro; Hirose, Yoshinobu; Yuki, Masako; Tsuda, Yasuhiro; Hayashi, Michihiro

    2016-07-01

    Pseudomyxoma peritonei (PMP) is characterized by extensive mucinous ascites following rupture of mucinous neoplasms of an intra-abdominal origin, and contain secreted gel-forming mucins such as MUC2 and MUC5AC. We encountered a 66-year-old Japanese man complaining of abdominal distension. Ascites at the site was gelatinous upon gross examination, and needle aspirate smears showed histiocytes and many mucinous balls wrapped in spindle cells, which were positive for vimentin, pan-cytokeratin, and podoplanin. The cell block showed several adenocarcinoma clusters, which were positive for MUC2, MUC5AC, CK20, and CDX-2, and negative for CK7. From these findings, a diagnosis of PMP arising from colon cancer was indicated. Cytoreductive surgery was performed, and the cystic diverticulum was found to be infiltrated by tumor cells in the sigmoid colon that caused PMP. Mucinous balls surrounded by mesothelial cells and MUC2-positive adenocarcinoma cells are useful clues in the diagnosis of PMP. Diagn. Cytopathol. 2016;44:628-631. © 2016 Wiley Periodicals, Inc. PMID:27079739

  11. The role of disulphide bonds in human intestinal mucin

    PubMed Central

    Forstner, Janet F.; Jabbal, Inderjit; Qureshi, Rauf; Kells, David I. C.; Forstner, Gordon G.

    1979-01-01

    Goblet-cell mucin (mucin 1) was isolated and purified from human small-intestinal scrapings. After application of mucin 1 to DEAE-Bio-Gel (A) columns, most of the glycoprotein (76–94% of hexoses) was eluted in the first peak (designated mucin 2). Minor amounts of acidic glycoproteins were eluted with 0.2m- and 0.4m-NaCl in later peaks. Analyses of mucin 1 and mucin 2 revealed mucin 2 to be a monodisperse highly glycosylated glycoprotein containing 6.3% by wt. of protein, N-acetylgalactosamine, N-acetylglucosamine, galactose and fucose. Mucin 1 was similar in composition, but was polydisperse and contained more protein (12.3% by wt.) as well as N-acetylneuraminic acid. Analytical CsCl-gradient ultracentrifugation showed both mucin 1 and mucin 2 to have a major component with an average buoyant density of 1.47000g/ml. Mucin 1 also contained a slightly less-dense minor glycoprotein component. After exhaustive reduction and alkylation mucin 1 retained its major component, but partly dissociated into two lighter glycoprotein components. Mucin 2, in contrast, did not change its density distribution after reduction. Band ultracentrifugation in 2H2O-containing iso-osmotic buffers showed that mucin 1 contained a major fast-sedimenting component (so=37±2S), and a minor amount of a slower-sedimenting component. After reduction there was an increased quantity of the latter component, for which an so value of 14.5S was calculated. In contrast, mucin 2 was unaltered by reduction (so=33±2S). These findings indicate that the major component of goblet-cell mucin (mucin 2) does not dissociate after S–S-bond reduction, and thus does not apparently rely for its polymeric structure on the association of subunits through covalent disulphide bonds. However, the effects of reduction on mucin 1 suggest that in the native mucin intramolecular disulphide bonds in the minor glycoproteins may stabilize their structure, permitting secondary non-covalent interactions to develop with the

  12. 17β-Estradiol inhibits Ca2+-dependent homeostasis of airway surface liquid volume in human cystic fibrosis airway epithelia

    PubMed Central

    Coakley, Ray D.; Sun, Hengrui; Clunes, Lucy A.; Rasmussen, Julia E.; Stackhouse, James R.; Okada, Seiko F.; Fricks, Ingrid; Young, Steven L.; Tarran, Robert

    2008-01-01

    Normal airways homeostatically regulate the volume of airway surface liquid (ASL) through both cAMP- and Ca2+-dependent regulation of ion and water transport. In cystic fibrosis (CF), a genetic defect causes a lack of cAMP-regulated CFTR activity, leading to diminished Cl– and water secretion from airway epithelial cells and subsequent mucus plugging, which serves as the focus for infections. Females with CF exhibit reduced survival compared with males with CF, although the mechanisms underlying this sex-related disadvantage are unknown. Despite the lack of CFTR, CF airways retain a limited capability to regulate ASL volume, as breathing-induced ATP release activates salvage purinergic pathways that raise intracellular Ca2+ concentration to stimulate an alternate pathway to Cl– secretion. We hypothesized that estrogen might affect this pathway by reducing the ability of airway epithelia to respond appropriately to nucleotides. We found that uridine triphosphate–mediated (UTP-mediated) Cl– secretion was reduced during the periovulatory estrogen maxima in both women with CF and normal, healthy women. Estrogen also inhibited Ca2+ signaling and ASL volume homeostasis in non-CF and CF airway epithelia by attenuating Ca2+ influx. This inhibition of Ca2+ signaling was prevented and even potentiated by estrogen antagonists such as tamoxifen, suggesting that antiestrogens may be beneficial in the treatment of CF lung disease because they increase Cl– secretion in the airways. PMID:19033671

  13. The distribution of mucous secreting cells in the gastrointestinal tracts of three small rodents from Saudi Arabia: Acomys dimidiatus, Meriones rex and Meriones libycus.

    PubMed

    Johnson, Olga; Marais, Sumine; Walters, Jacklynn; van der Merwe, Elizabeth L; Alagaili, Abdulaziz N; Mohammed, Osama B; Bennett, Nigel C; Kotzé, Sanet H

    2016-03-01

    The proportion of mucin phenotypes (which form the protective biofilm of the gastrointestinal tract) differs between intestinal regions. This study examines the distribution of mucin secreting cells in the gastrointestinal tracts of the Eastern spiny mouse (Acomys dimidiatus), King jird (Meriones rex) and Libyan jird (Meriones libycus), which inhabit the dry and hot deserts of Saudi Arabia. Intestinal tract samples were processed to wax and tissue sections stained with Alcian Blue-Periodic Acid Schiff (AB-PAS) and High Iron Diamine-Alcian Blue (HID-AB) in order to determine different mucin phenotypes by quantitative analysis. Mixed mucin secreting cells (combined neutral and acid) was the predominant mucin secreting cell type observed throughout the gastrointestinal tract in all species. Acid mucin secreting goblet cells were mainly located in the colon. A. dimidiatus presented with significantly more total sialo than sulfomucin secreting cells while the opposite was true for both Meriones species. The distribution of mucin secreting cells is therefore similar to previously reported results for small mammals not living under arid conditions. PMID:26743350

  14. Retroperitoneal mucinous cystadenoma of the appendix mimicking hydatid cyst: A case report

    PubMed Central

    Sikar, Hasan Ediz; Çetin, Kenan; Gündoğan, Ersin; Gündoğan, Gökçen Alinak; Kaptanoğlu, Levent

    2016-01-01

    Appendiceal mucocele is a cystic dilatation of the appendix due to abnormal appendiceal mucinous secretion. Cystadenoma of the appendix is one of the most common causes and is encountered in 0.6% of all appendectomy specimens. The diagnosis may be difficult due to the asymptomatic nature of the disease; pain in the right lower quadrant may be the only symptom. Complex ovarian cyst, urolithiasis or cystic hydatid disease of the liver have been reported as mimicking appendiceal mucocele in the literature. In this study, we present a case of mucinous cystadenoma of the appendix mimicking retroperitoneal hydatid cyst in a 59-year-old woman. The patient was treated with laparoscopic appendectomy with partial resection of the caecum following laparoscopic exploration.

  15. Salivary mucins in host defense and disease prevention.

    PubMed

    Frenkel, Erica Shapiro; Ribbeck, Katharina

    2015-01-01

    Mucus forms a protective coating on wet epithelial surfaces throughout the body that houses the microbiota and plays a key role in host defense. Mucins, the primary structural components of mucus that creates its viscoelastic properties, are critical components of the gel layer that protect against invading pathogens. Altered mucin production has been implicated in diseases such as ulcerative colitis, asthma, and cystic fibrosis, which highlights the importance of mucins in maintaining homeostasis. Different types of mucins exist throughout the body in various locations such as the gastrointestinal tract, lungs, and female genital tract, but this review will focus on mucins in the oral cavity. Salivary mucin structure, localization within the oral cavity, and defense mechanisms will be discussed. These concepts will then be applied to present what is known about the protective function of mucins in oral diseases such as HIV/AIDS, oral candidiasis, and dental caries. PMID:26701274

  16. Salivary mucins in host defense and disease prevention

    PubMed Central

    Frenkel, Erica Shapiro; Ribbeck, Katharina

    2015-01-01

    Mucus forms a protective coating on wet epithelial surfaces throughout the body that houses the microbiota and plays a key role in host defense. Mucins, the primary structural components of mucus that creates its viscoelastic properties, are critical components of the gel layer that protect against invading pathogens. Altered mucin production has been implicated in diseases such as ulcerative colitis, asthma, and cystic fibrosis, which highlights the importance of mucins in maintaining homeostasis. Different types of mucins exist throughout the body in various locations such as the gastrointestinal tract, lungs, and female genital tract, but this review will focus on mucins in the oral cavity. Salivary mucin structure, localization within the oral cavity, and defense mechanisms will be discussed. These concepts will then be applied to present what is known about the protective function of mucins in oral diseases such as HIV/AIDS, oral candidiasis, and dental caries. PMID:26701274

  17. Mucins in lung cancer: diagnostic, prognostic, and therapeutic implications.

    PubMed

    Lakshmanan, Imayavaramban; Ponnusamy, Moorthy P; Macha, Muzafar A; Haridas, Dhanya; Majhi, Prabin Dhangada; Kaur, Sukhwinder; Jain, Maneesh; Batra, Surinder K; Ganti, Apar Kishor

    2015-01-01

    Aberrant expression of mucins is associated with cancer development and metastasis. An overexpression of few mucins contributes to oncogenesis by enhancing cancer cell growth and providing constitutive survival signals. This review focuses on the importance of mucins both in the normal bronchial epithelial cells and the malignant tumors of the lung and their contribution in the diagnosis and prognosis of lung cancer patients. During lung cancer progression, mucins either alone or through their interaction with many receptor tyrosine kinases mediate cell signals for growth and survival of cancer cells. Also, stage-specific expression of certain mucins, like MUC1, is associated with poor prognosis from lung cancer. Thus, mucins are emerging as attractive targets for developing novel therapeutic approaches for lung cancer. Several strategies targeting mucin expression and function are currently being investigated to control lung cancer progression. PMID:25319180

  18. Quantitative microscopic evaluation of mucin areas and its percentage in mucinous carcinoma of the breast using tissue histological images.

    PubMed

    Saha, Monjoy; Arun, Indu; Basak, Bijan; Agarwal, Sanjit; Ahmed, Rosina; Chatterjee, Sanjoy; Bhargava, Rohit; Chakraborty, Chandan

    2016-06-01

    Mucinous carcinoma (MC) of the breast is very rare (∼1-7% of all breast cancers), invasive ductal carcinoma. Presence of pools of extracellular mucin is one of the most important histological features for MC. This paper aims at developing a quantitative computer-aided methodology for automated identification of mucin areas and its percentage using tissue histological images. The proposed method includes pre-processing (i.e., colour space transformation and colour normalization), mucin regions segmentation, post-processing, and performance evaluation. The proposed algorithm achieved 97.74% segmentation accuracy in comparison to ground truths. In addition, the percentage of mucin present in the tissue regions is calculated by the mucin index (MI) for grading MC (pure, moderately, minimally mucinous). PMID:26971129

  19. Regulation of airway neurogenic inflammation by neutral endopeptidase.

    PubMed

    Di Maria, G U; Bellofiore, S; Geppetti, P

    1998-12-01

    Airway neurogenic inflammation is caused by tachykinins released from peripheral nerve endings of sensory neurons within the airways, and is characterized by plasma protein extravasation, airway smooth muscle contraction and increased secretion of mucus. Tachykinins are degraded and inactivated by neutral endopeptidase (NEP), a membrane-bound metallopeptidase, which is located mainly at the surface of airway epithelial cells, but is also present in airway smooth muscle cells, submucosal gland cells and fibroblasts. The key role of NEP in limiting and regulating the neurogenic inflammation provoked by different stimuli has been demonstrated in a large series of studies published in recent years. It has also been shown that a variety of factors, which are relevant for airway diseases, including viral infections, allergen exposure, inhalation of cigarette smoke and other respiratory irritants, is able to reduce NEP activity, thus enhancing the effects of tachykinins within the airways. On the basis of these observations, the reduction of neutral endopeptidase activity may be regarded as a factor that switches neurogenic airway responses from their physiological and protective functions to a detrimental role that increases and perpetuates airway inflammation. However, further studies are needed to assess the role of neutral endopeptidase down regulation in the pathogenesis of asthma and other inflammatory airway diseases. PMID:9877509

  20. Upper airway test (image)

    MedlinePlus

    An upper airway biopsy is obtained by using a flexible scope called a bronchoscope. The scope is passed down through ... may be performed when an abnormality of the upper airway is suspected. It may also be performed as ...

  1. Delivery of a mucin domain enriched in cysteine residues strengthens the intestinal mucous barrier.

    PubMed

    Gouyer, Valérie; Dubuquoy, Laurent; Robbe-Masselot, Catherine; Neut, Christel; Singer, Elisabeth; Plet, Ségolène; Geboes, Karel; Desreumaux, Pierre; Gottrand, Frédéric; Desseyn, Jean-Luc

    2015-01-01

    A weakening of the gut mucous barrier permits an increase in the access of intestinal luminal contents to the epithelial cells, which will trigger the inflammatory response. In inflammatory bowel diseases, there is an inappropriate and ongoing activation of the immune system, possibly because the intestinal mucus is less protective against the endogenous microflora. General strategies aimed at improving the protection of the intestinal epithelium are still missing. We generated a transgenic mouse that secreted a molecule consisting of 12 consecutive copies of a mucin domain into its intestinal mucus, which is believed to modify the mucus layer by establishing reversible interactions. We showed that the mucus gel was more robust and that mucin O-glycosylation was altered. Notably, the gut epithelium of transgenic mice housed a greater abundance of beneficial Lactobacillus spp. These modifications were associated with a reduced susceptibility of transgenic mice to chemically induced colitis. Furthermore, transgenic mice cleared faster Citrobacter rodentium bacteria which were orally given and mice were more protected against bacterial translocation induced by gavage with adherent-invasive Escherichia coli. Our data show that delivering the mucin CYS domain into the gut lumen strengthens the intestinal mucus blanket which is impaired in inflammatory bowel diseases. PMID:25974250

  2. Delivery of a mucin domain enriched in cysteine residues strengthens the intestinal mucous barrier

    PubMed Central

    Gouyer, Valérie; Dubuquoy, Laurent; Robbe-Masselot, Catherine; Neut, Christel; Singer, Elisabeth; Plet, Ségolène; Geboes, Karel; Desreumaux, Pierre; Gottrand, Frédéric; Desseyn, Jean-Luc

    2015-01-01

    A weakening of the gut mucous barrier permits an increase in the access of intestinal luminal contents to the epithelial cells, which will trigger the inflammatory response. In inflammatory bowel diseases, there is an inappropriate and ongoing activation of the immune system, possibly because the intestinal mucus is less protective against the endogenous microflora. General strategies aimed at improving the protection of the intestinal epithelium are still missing. We generated a transgenic mouse that secreted a molecule consisting of 12 consecutive copies of a mucin domain into its intestinal mucus, which is believed to modify the mucus layer by establishing reversible interactions. We showed that the mucus gel was more robust and that mucin O-glycosylation was altered. Notably, the gut epithelium of transgenic mice housed a greater abundance of beneficial Lactobacillus spp. These modifications were associated with a reduced susceptibility of transgenic mice to chemically induced colitis. Furthermore, transgenic mice cleared faster Citrobacter rodentium bacteria which were orally given and mice were more protected against bacterial translocation induced by gavage with adherent–invasive Escherichia coli. Our data show that delivering the mucin CYS domain into the gut lumen strengthens the intestinal mucus blanket which is impaired in inflammatory bowel diseases. PMID:25974250

  3. Mucinous ovarian cancer: A therapeutic review.

    PubMed

    Xu, Wen; Rush, Jack; Rickett, Kirsty; Coward, Jermaine I G

    2016-06-01

    Mucinous ovarian cancer represents approximately 3% of epithelial ovarian cancers (EOC). Despite this seemingly low prevalence, it remains a diagnostic and therapeutic conundrum that has resulted in numerous attempts to adopt novel strategies in managing this disease. Anecdotally, there has been a prevailing notion that established gold standard systemic regimens should be substituted for those utilised in cancers such as gastrointestinal (GI) malignancies; tumours that share more biological similarities than other EOC subtypes. This review summarises the plethora of small studies which have adopted this philosophy and influenced the design of the multinational GOG142 study, which was ultimately terminated due to poor accrual. To date, there is a paucity of evidence to support delivering 'GI style' chemotherapy for mucinous ovarian cancer over and above carboplatin-paclitaxel doublet therapy. Hence there is an urge to develop studies focused on targeted therapeutic agents driven by refined mutational analysis and conducted within the context of harmonised international collaborations. PMID:27083591

  4. Physiology of Epithelial Chloride and Fluid Secretion

    PubMed Central

    Frizzell, Raymond A.; Hanrahan, John W.

    2012-01-01

    Epithelial salt and water secretion serves a variety of functions in different organ systems, such as the airways, intestines, pancreas, and salivary glands. In cystic fibrosis (CF), the volume and/or composition of secreted luminal fluids are compromised owing to mutations in the gene encoding CFTR, the apical membrane anion channel that is responsible for salt secretion in response to cAMP/PKA stimulation. This article examines CFTR and related cellular transport processes that underlie epithelial anion and fluid secretion, their regulation, and how these processes are altered in CF disease to account for organ-specific secretory phenotypes. PMID:22675668

  5. Careers in Airway Science.

    ERIC Educational Resources Information Center

    Federal Aviation Administration (DOT), Washington, DC.

    The Federal Aviation Administration (FAA) has initiated the Airway Science curriculum as a method of preparing the next generation of aviation technicians and managers. This document: (1) discusses the FAA's role in the Airway Science program; (2) describes some of the career fields that FAA offers to Airway Science graduates (air traffic control…

  6. NEU1 Sialidase Regulates Membrane-tethered Mucin (MUC1) Ectodomain Adhesiveness for Pseudomonas aeruginosa and Decoy Receptor Release.

    PubMed

    Lillehoj, Erik P; Hyun, Sang Won; Liu, Anguo; Guang, Wei; Verceles, Avelino C; Luzina, Irina G; Atamas, Sergei P; Kim, K Chul; Goldblum, Simeon E

    2015-07-24

    Airway epithelia express sialylated receptors that recognize exogenous danger signals. Regulation of receptor responsiveness to these signals remains incompletely defined. Here, we explore the mechanisms through which the human sialidase, neuraminidase-1 (NEU1), promotes the interaction between the sialoprotein, mucin 1 (MUC1), and the opportunistic pathogen, Pseudomonas aeruginosa. P. aeruginosa flagellin engaged the MUC1 ectodomain (ED), increasing NEU1 association with MUC1. The flagellin stimulus increased the association of MUC1-ED with both NEU1 and its chaperone/transport protein, protective protein/cathepsin A. Scatchard analysis demonstrated NEU1-dependent increased binding affinity of flagellin to MUC1-expressing epithelia. NEU1-driven MUC1-ED desialylation rapidly increased P. aeruginosa adhesion to and invasion of the airway epithelium. MUC1-ED desialylation also increased its shedding, and the shed MUC1-ED competitively blocked P. aeruginosa adhesion to cell-associated MUC1-ED. Levels of desialylated MUC1-ED were elevated in the bronchoalveolar lavage fluid of mechanically ventilated patients with P. aeruginosa airway colonization. Preincubation of P. aeruginosa with these same ex vivo fluids competitively inhibited bacterial adhesion to airway epithelia, and MUC1-ED immunodepletion completely abrogated their inhibitory activity. These data indicate that a prokaryote, P. aeruginosa, in a ligand-specific manner, mobilizes eukaryotic NEU1 to enhance bacterial pathogenicity, but the host retaliates by releasing MUC1-ED into the airway lumen as a hyperadhesive decoy receptor. PMID:25963144

  7. Folding and Aggregation of Mucin Domains.

    NASA Astrophysics Data System (ADS)

    Urbanc, Brigita; Bansil, Rama; Turner, Bradley

    2007-03-01

    Mucin glycoproteins consist of tandem repeating glycosylated regions flanked by non-repetitive protein domains with little glycosylation. These non-repetitive domains are involved in polymerization of mucin via disulfide bonds and play an important role in the pH dependent gelation of gastric mucin, which is essential to protecting the stomach from autodigestion. We have examined the folding and aggregation of the non-repetitive sequence of von Willebrand factor vWF-C1 domain (67 amino acids) and PGM 2X (242 amino acids) using Discrete Molecular Dynamics (four-bead protein model with hydrogen bonding and amino acid-specific hydrophobic/hydrophilic and electrostatic interactions of side chains). Simulations of vWF C1 show 4-6 β-strands separated by turns/loops with more loops at lower pH. A simulation of several vWF C1 proteins at low pH shows aggregates still with a high content of β-strands and enhanced turn/loop regions. For the PGM 2X simulation the contact map shows several salt bridges enclosing hairpin turns. The implications of these simulations for describing the aggregation/gelation of PGM will be discussed.

  8. Expression of MUC5AC and MUC5B mucins in normal and cystic fibrosis lung.

    PubMed

    Groneberg, D A; Eynott, P R; Oates, T; Lim, S; Wu, R; Carlstedt, I; Nicholson, A G; Chung, K F

    2002-02-01

    Hypersecretion of airway mucus is a characteristic feature of chronic airway diseases like cystic fibrosis (CF) and leads via impairment of the muco-ciliary clearance and bacterial superinfection to respiratory failure. The major components of the mucus matrix forming family of mucins in the airways are MUC5AC and MUC5B. To investigate the expression of these glycoproteins in CF, immunohistochemistry was carried out on trachea, bronchi and peripheral lung obtained from CF patients and compared to normal lung tissues. MUC5AC immunohistochemistry demonstrated signals in goblet cells of the epithelial lining. Also, goblet cells inside glandular secretory ducts revealed MUC5AC-positive staining. In comparison to those from normal subjects, CF sections were characterized by inflammatory changes and goblet cell hyperplasia, resulting in increased numbers of MUC5AC-positive cells. Immunohistochemical staining for MUC5B showed abundant staining of submucosal glands and epithelial goblet cells. Inside the glands, the immunoreactivity was restricted to glandular mucous cells. MUC5AC and MUC5B are expressed in the same histological pattern in CF compared to normal tissues with an increase of MUC5AC-positive cells due to goblet cell hyper- and metaplasia. PMID:11860173

  9. Mucin-producing tumors of the ovary: MR imaging appearance.

    PubMed

    Laurent, P-E; Thomassin-Piana, J; Jalaguier-Coudray, A

    2015-11-01

    Mucin-producing tumors of the ovary can be either primary epithelial mucin-producing tumors or ovarian metastases from a remote adenocarcinoma usually originating from the gastrointestinal tract. The purpose of this pictorial review is to describe the main types of primary or secondary mucin-producing tumors of the ovary and to provide MR imaging diagnostic criteria in order to guide further therapy. PMID:25753545

  10. Expression of REG4 in ovarian mucinous tumors.

    PubMed

    Huang, Qiong; Chen, Xiaoduan; Lu, Weiguo; Lai, Maode; Lu, Bingjian

    2014-04-01

    Regenerating islet-deprived gene family, number 4 (REG4), is a novel marker for intestinal differentiation. We performed immunohistochemical studies on REG4, cytokeratin (CK)7, CK20, and caudal type homeobox 2 (CDX2) in 291 ovarian mucinous tumors. There were 226 primary tumors and 65 metastatic tumors. The primary tumors comprised 69/226 mucinous cystadenomas, 79/226 mucinous borderline tumors (64/79 intestinal-type and 15/79 endocervical-like tumors), and 78/226 mucinous carcinomas. We found that REG4 expression was significantly higher in mucinous borderline tumors (30/79, 38.0%) and primary mucinous carcinomas (26/78, 33.3%) than in mucinous cystadenomas (4/69, 5.8%; P<0.05). However, REG4 expression was more commonly associated with intestinal-type, borderline, mucinous tumors rather than the endocervical-like type (30/64 vs. 0/15, P<0.001). There was a significant correlation between the REG4 and CDX2 expression profiles in primary ovarian mucinous tumors (r=0.772, P<0.001). REG4, CDX2, and diffuse CK20 had higher expression frequencies in metastatic lower gastrointestinal adenocarcinoma than in primary mucinous tumors (P<0.01). The CK7/REG4 coordinate expression profile was comparable in diagnostic value to CK7/CK20 or CK7/CDX2 profile. We conclude that REG4 expression is common in mucinous borderline tumors of the intestinal type as it is absent in the endocervical-like form in this series. Expression of CK7/REG4 may contribute to the differential diagnosis between primary and metastatic ovarian mucinous tumors. PMID:23958547

  11. Structure and function of airway surface layer of the human lungs & mobility of probe particles in complex fluids

    NASA Astrophysics Data System (ADS)

    Cai, Liheng

    Numerous infectious particles such as bacteria and pathogens are deposited on the airway surface of the human lungs during our daily breathing. To avoid infection the lung has evolved to develop a smart and powerful defense system called mucociliary clearance. The airway surface layer is a critical component of this mucus clearance system, which consists of two parts: (1) a mucus layer, that traps inhaled particles and transports them out of the lung by cilia-generated flow; and (2) a periciliary layer, that provides a favorable environment for ciliary beating and cell surface lubrication. For 75 years, it has been dogma that a single gel-like mucus layer, which is composed of secreted mucin glycoproteins, is transported over a "watery" periciliary layer. This one-gel model, however, does not explain fundamental features of the normal system, e.g. formation of a distinct mucus layer, nor accurately predict how the mucus clearance system fails in disease. In the first part of this thesis we propose a novel "Gel-on-Brush" model with a mucus layer (the "gel") and a "brush-like" periciliary layer, composed of mucins tethered to the luminal of airway surface, and supporting data accurately describes both the biophysical and cell biological bases for normal mucus clearance and its failure in disease. Our "Gel-on-Brush" model describes for the first time how and why mucus is efficiently cleared in health and unifies the pathogenesis of major human diseases, including cystic fibrosis and chronic obstructive pulmonary disease. It is expected that this "Gel-on-Brush" model of airway surface layer opens new directions for treatments of airway diseases. A dilemma regarding the function of mucus is that, although mucus traps any inhaled harmful particulates, it also poses a long-time problem for drug delivery: mobility of cargos carrying pharmaceutical agents is slowed down in mucus. The second part of this thesis aims to answer the question: can we theoretically understand the

  12. Interaction of cellulose-based cationic polyelectrolytes with mucin.

    PubMed

    Mazoniene, Edita; Joceviciute, Simona; Kazlauske, Jurgita; Niemeyer, Bernd; Liesiene, Jolanta

    2011-03-01

    Mucoadhesivity of water-soluble polymers is an important factor, when testing their suitability for controlled drug delivery systems. For this purpose, the interaction of new cationic cellulose polyelectrolytes with lyophilized mucin was investigated by means of turbidimetric titration, microscopy and measurement of zeta potential and particle size changes in the system. Results show that the cellulose derivatives interact with mucin. This interaction became stronger if cellulose macromolecules contained positively charged groups and an electrostatic interaction with the negatively charged mucin particles occurred. Under certain conditions flocculation of mucin particles by the cellulose polyelectrolyte was observed. PMID:21134731

  13. Arylhydrocarbon receptor (AhR) activation in airway epithelial cells induces MUC5AC via reactive oxygen species (ROS) production.

    PubMed

    Chiba, Takahito; Uchi, Hiroshi; Tsuji, Gaku; Gondo, Hisaki; Moroi, Yoichi; Furue, Masutaka

    2011-02-01

    The dioxins and dioxin-like compounds in cigarette smoke regulate various immunological responses via the arylhydrocarbon receptor (AhR). These environmental toxicants are known to cause bronchitis, asthma, chronic obstructive pulmonary disease (COPD), and lung cancer. Recent studies have demonstrated that AhR activation upregulates the expression of mucin 5AC, oligomeric mucus/gel-forming (MUC5AC) in the airway epithelial cell line. However, the mechanism for the production of mucin has not been clarified. In this study, we investigated the role and pathway of AhR in airway epithelial cells by using selective agonists and antagonists. After stimulation with or without benzopyrene (B[a]P), an AhR agonist, MUC5AC expression was measured by real-time RT-PCR. The mechanism of AhR-induced MUC5AC expression in airway epithelial cells was studied in terms of the production of cytokine and reactive oxygen species (ROS). Treatment with B[a]P increased ROS generation in NCI-H₂₉₂ cells. Furthermore, B[a]P-induced MUC5AC upregulation and mucin production were inhibited by AhR siRNA or the use of an antioxidative agent. These results suggest that the AhR-induced increase of mucin production is partially mediated by ROS generation. An antioxidant therapy approach may help to cure AhR-induced mucus hypersecretory diseases. PMID:20709182

  14. The Physiologically Difficult Airway.

    PubMed

    Mosier, Jarrod M; Joshi, Raj; Hypes, Cameron; Pacheco, Garrett; Valenzuela, Terence; Sakles, John C

    2015-12-01

    Airway management in critically ill patients involves the identification and management of the potentially difficult airway in order to avoid untoward complications. This focus on difficult airway management has traditionally referred to identifying anatomic characteristics of the patient that make either visualizing the glottic opening or placement of the tracheal tube through the vocal cords difficult. This paper will describe the physiologically difficult airway, in which physiologic derangements of the patient increase the risk of cardiovascular collapse from airway management. The four physiologically difficult airways described include hypoxemia, hypotension, severe metabolic acidosis, and right ventricular failure. The emergency physician should account for these physiologic derangements with airway management in critically ill patients regardless of the predicted anatomic difficulty of the intubation. PMID:26759664

  15. The Physiologically Difficult Airway

    PubMed Central

    Mosier, Jarrod M.; Joshi, Raj; Hypes, Cameron; Pacheco, Garrett; Valenzuela, Terence; Sakles, John C.

    2015-01-01

    Airway management in critically ill patients involves the identification and management of the potentially difficult airway in order to avoid untoward complications. This focus on difficult airway management has traditionally referred to identifying anatomic characteristics of the patient that make either visualizing the glottic opening or placement of the tracheal tube through the vocal cords difficult. This paper will describe the physiologically difficult airway, in which physiologic derangements of the patient increase the risk of cardiovascular collapse from airway management. The four physiologically difficult airways described include hypoxemia, hypotension, severe metabolic acidosis, and right ventricular failure. The emergency physician should account for these physiologic derangements with airway management in critically ill patients regardless of the predicted anatomic difficulty of the intubation. PMID:26759664

  16. Induction of IL-12 Production in Human Peripheral Monocytes by Trypanosoma cruzi Is Mediated by Glycosylphosphatidylinositol-Anchored Mucin-Like Glycoproteins and Potentiated by IFN-γ and CD40-CD40L Interactions

    PubMed Central

    Abel, Lúcia Cristina Jamli; Ferreira, Ludmila Rodrigues Pinto; Cunha Navarro, Isabela; Baron, Monique Andrade; Kalil, Jorge; Gazzinelli, Ricardo Tostes; Rizzo, Luiz Vicente; Cunha-Neto, Edecio

    2014-01-01

    Chagas disease, caused by the protozoan parasite Trypanosoma cruzi (T. cruzi), is characterized by immunopathology driven by IFN-γ secreting Th1-like T cells. T. cruzi has a thick coat of mucin-like glycoproteins covering its surface, which plays an important role in parasite invasion and host immunomodulation. It has been extensively described that T. cruzi or its products—like GPI anchors isolated from GPI-anchored mucins from the trypomastigote life cycle stage (tGPI-mucins)—are potent inducers of proinflammatory responses (i.e., cytokines and NO production) by IFN-γ primed murine macrophages. However, little is known about whether T. cruzi or GPI-mucins exert a similar action in human cells. We therefore decided to further investigate the in vitro cytokine production profile from human mononuclear cells from uninfected donors exposed to T. cruzi as well as tGPI-mucins. We observed that both living T. cruzi trypomastigotes and tGPI-mucins are potent inducers of IL-12 by human peripheral blood monocytes and this effect depends on CD40-CD40L interaction and IFN-γ. Our findings suggest that the polarized T1-type cytokine profile seen in T. cruzi infected patients might be a long-term effect of IL-12 production induced by lifelong exposure to T. cruzi tGPI-mucins. PMID:25120285

  17. LIGHT is a crucial mediator of airway remodeling.

    PubMed

    Hung, Jen-Yu; Chiang, Shyh-Ren; Tsai, Ming-Ju; Tsai, Ying-Ming; Chong, Inn-Wen; Shieh, Jiunn-Min; Hsu, Ya-Ling

    2015-05-01

    Chronic inflammatory airway diseases like asthma and chronic obstructive pulmonary disease are major health problems globally. Airway epithelial cells play important role in airway remodeling, which is a critical process in the pathogenesis of diseases. This study aimed to demonstrate that LIGHT, an inflammatory factor secreted by T cells after allergen exposure, is responsible for promoting airway remodeling. LIGHT increased primary human bronchial epithelial cells (HBECs) undergoing epithelial-mesenchymal transition (EMT) and expressing MMP-9. The induction of EMT was associated with increased NF-κB activation and p300/NF-κB association. The interaction of NF-κB with p300 facilitated NF-κB acetylation, which in turn, was bound to the promoter of ZEB1, resulting in E-cadherin downregulation. LIGHT also stimulated HBECs to produce numerous cytokines/chemokines that could worsen airway inflammation. Furthermore, LIGHT enhanced HBECs to secrete activin A, which increased bronchial smooth muscle cell (BSMC) migration. In contrast, depletion of activin A decreased such migration. The findings suggest a new molecular determinant of LIGHT-mediated pathogenic changes in HBECs and that the LIGHT-related vicious cycle involving HBECs and BSMCs may be a potential target for the treatment of chronic inflammation airway diseases with airway remodeling. PMID:25251281

  18. The pharmacologic approach to airway clearance: mucoactive agents.

    PubMed

    Rubin, Bruce K

    2006-01-01

    The term "mucoactive agent" refers to any medication used to improve the clearance of airway secretions. It is not synonymous with the word "mucolytic" as this strictly means a drug that decreases the viscosity of secretions. In many cases, decreased viscosity will adversely affect cough transport. For this reason many of the older mucolytic agents such as acetylcysteine are not effective for the therapy of lung disease and their use is not recommended. I review here the many classes of mucoactive agents and identify a number of medications with great promise for the treatment of chronic airway disease. PMID:16798570

  19. Frequent GNAS mutations in low-grade appendiceal mucinous neoplasms

    PubMed Central

    Nishikawa, G; Sekine, S; Ogawa, R; Matsubara, A; Mori, T; Taniguchi, H; Kushima, R; Hiraoka, N; Tsuta, K; Tsuda, H; Kanai, Y

    2013-01-01

    Background: The molecular basis for the development of appendiceal mucinous tumours, which can be a cause of pseudomyxoma peritonei, remains largely unknown. Methods: Thirty-five appendiceal mucinous neoplasms were analysed for GNAS and KRAS mutations. A functional analysis of mutant GNAS was performed using a colorectal cancer cell line. Results: A mutational analysis identified activating GNAS mutations in 16 of 32 low-grade appendiceal mucinous neoplasms (LAMNs) but in none of three mucinous adenocarcinomas (MACs). KRAS mutations were found in 30 LAMNs and in all MACs. We additionally analysed a total of 186 extra-appendiceal mucinous tumours and found that GNAS mutations were highly prevalent in intraductal papillary mucinous tumours of the pancreas (88%) but were rare or absent in mucinous tumours of the colorectum, ovary, lung and breast (0–9%). The prevalence of KRAS mutations was quite variable among the tumours. The introduction of the mutant GNAS into a colorectal cancer cell line markedly induced MUC2 and MUC5AC expression, but did not promote cell growth either in vitro or in vivo. Conclusion: Activating GNAS mutations are a frequent and characteristic genetic abnormality of LAMN. Mutant GNAS might play a direct role in the prominent mucin production that is a hallmark of LAMN. PMID:23403822

  20. Heterogeneity and persistence length in human ocular mucins.

    PubMed Central

    Round, A N; Berry, M; McMaster, T J; Stoll, S; Gowers, D; Corfield, A P; Miles, M J

    2002-01-01

    Atomic force microscopy (AFM) has been used to investigate the heterogeneity and flexibility of human ocular mucins and their subunits. We have paid particular attention, in terms of theory and experiment, to the problem of inducing the polymers to assume equilibrium conformations at a surface. Mucins deposited from a buffer containing Ni(2+) ions adopt extended conformations on mica akin to those observed for DNA under similar conditions. The heterogeneity of the intracellular native mucins is evident from a histogram of contour lengths, reflecting, in part, the diversity of mucin gene products expressed. Reduction of the native mucin with dithiothreitol, thereby breaking the S==S bonds between cysteine residues, causes a marked reduction in polymer length. These results reflect the modes of transport and assembly of newly synthesized mucins in vivo. By modifying the worm-like chain model for applicability to two dimensions, we have confirmed that under the conditions employed mucin adsorbs to mica in an equilibrated conformation. The determined persistence length of the native mucin, 36 nm, is consistent with that of an extended, flexible polymer; such characteristics will influence the properties of the gels formed in vivo. PMID:12202389

  1. 76 FR 13083 - Amendment to VOR Federal Airway V-358; TX

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-10

    ... Federal Register amending thirteen Federal airways in the vicinity of Dallas/ Fort Worth, TX (65 FR 61087... (66 FR 50101). The realignment around P-49 was necessary to assist the United States Secret Service in... in the Federal Register amending the V-358 airway description (74 FR 54896). That rule renamed...

  2. Engineering Airway Epithelium

    PubMed Central

    Soleas, John P.; Paz, Ana; Marcus, Paula; McGuigan, Alison; Waddell, Thomas K.

    2012-01-01

    Airway epithelium is constantly presented with injurious signals, yet under healthy circumstances, the epithelium maintains its innate immune barrier and mucociliary elevator function. This suggests that airway epithelium has regenerative potential (I. R. Telford and C. F. Bridgman, 1990). In practice, however, airway regeneration is problematic because of slow turnover and dedifferentiation of epithelium thereby hindering regeneration and increasing time necessary for full maturation and function. Based on the anatomy and biology of the airway epithelium, a variety of tissue engineering tools available could be utilized to overcome the barriers currently seen in airway epithelial generation. This paper describes the structure, function, and repair mechanisms in native epithelium and highlights specific and manipulatable tissue engineering signals that could be of great use in the creation of artificial airway epithelium. PMID:22523471

  3. Curcumin regulates airway epithelial cell cytokine responses to the pollutant cadmium

    SciTech Connect

    Rennolds, Jessica; Malireddy, Smitha; Hassan, Fatemat; Tridandapani, Susheela; Parinandi, Narasimham; Boyaka, Prosper N.; Cormet-Boyaka, Estelle

    2012-01-06

    Highlights: Black-Right-Pointing-Pointer Cadmium induces secretion of IL-6 and IL-8 by two distinct pathways. Black-Right-Pointing-Pointer Cadmium increases NAPDH oxidase activity leading to Erk activation and IL-8 secretion. Black-Right-Pointing-Pointer Curcumin prevents cadmium-induced secretion of both IL-6 and IL-8 by airway cells. Black-Right-Pointing-Pointer Curcumin could be use to suppress lung inflammation due to cadmium inhalation. -- Abstract: Cadmium is a toxic metal present in the environment and its inhalation can lead to pulmonary disease such as lung cancer and chronic obstructive pulmonary disease. These lung diseases are characterized by chronic inflammation. Here we show that exposure of human airway epithelial cells to cadmium promotes a polarized apical secretion of IL-6 and IL-8, two pivotal pro-inflammatory cytokines known to play an important role in pulmonary inflammation. We also determined that two distinct pathways controlled secretion of these proinflammatory cytokines by human airway epithelial cells as cadmium-induced IL-6 secretion occurs via an NF-{kappa}B dependent pathway, whereas IL-8 secretion involves the Erk1/2 signaling pathway. Interestingly, the natural antioxidant curcumin could prevent both cadmium-induced IL-6 and IL-8 secretion by human airway epithelial cells. In conclusion, curcumin could be used to prevent airway inflammation due to cadmium inhalation.

  4. Structural insights into bacterial recognition of intestinal mucins.

    PubMed

    Etzold, Sabrina; Juge, Nathalie

    2014-10-01

    The mucosal layer covering our gut epithelium represents the first line of host defenses against the luminal content, while enabling contacts between the resident microbiota and the host. Mucus is mainly composed of mucins, large glycoproteins containing a protein core and a high number of O-linked oligosaccharides. Mucin glycans act as binding sites or carbon sources for the intestinal microbes, thereby functioning as a host-specific determinant affecting the microbiota composition and human health. Reflecting the structural diversity of mucin glycans and their prime location, commensal and pathogenic microbes have evolved a range of adhesins allowing their interaction with the host. However, despite the recognised importance of mucin glycans in modulating intestinal homeostasis, information on carbohydrate-binding proteins from gut bacteria is disparate. This review is focussed on recent structural insights into host-microbe interactions mediated by mucins. PMID:25106027

  5. Altered Mucins (MUC) Trafficking in Benign and Malignant Conditions

    PubMed Central

    Joshi, Suhasini; Kumar, Sushil; Choudhury, Amit; Ponnusamy, Moorthy P.; Batra, Surinder K.

    2014-01-01

    Mucins are high molecular weight O-glycoproteins that are predominantly expressed at the apical surface of epithelial cells and have wide range of functions. The functional diversity is attributed to their structure that comprises of a peptide chain with unique domains and multiple carbohydrate moieties added during posttranslational modifications. Tumor cells aberrantly overexpress mucins, and thereby promote proliferation, differentiation, motility, invasion and metastasis. Along with their aberrant expression, accumulating evidence suggest the critical role of altered subcellular localization of mucins under pathological conditions due to altered endocytic processes. The mislocalization of mucins and their interactions result in change in the density and activity of important cell membrane proteins (like, receptor tyrosine kinases) to facilitate various signaling, which help cancer cells to proliferate, survive and progress to more aggressive phenotype. In this review article, we summarize studies on mucins trafficking and provide a perspective on its importance to pathological conditions and to answer critical questions including its use for therapeutic interventions. PMID:25261375

  6. Interferon-γ-Induced Unfolded Protein Response in Conjunctival Goblet Cells as a Cause of Mucin Deficiency in Sjögren Syndrome.

    PubMed

    Coursey, Terry G; Tukler Henriksson, Johanna; Barbosa, Flavia L; de Paiva, Cintia S; Pflugfelder, Stephen C

    2016-06-01

    Goblet cells (GCs) are specialized secretory cells that produce mucins and a variety of other proteins. Significant conjunctival GC loss occurs in both experimental dry eye models and patients with keratoconjunctivitis sicca due to the induction of interferon (IFN)-γ. With the use of a primary murine culture model, we found that GCs are highly sensitive to IFN-γ with significantly reduced proliferation and altered structure with low concentrations. GC cultures treated with IFN-γ have increased gene expression of Muc2 and Muc5AC but do not express these mucin glycoproteins. We hypothesized that IFN-γ induces endoplasmic reticulum stress and the unfolded protein response (UPR) in GCs. Cultures treated with IFN-γ increased expression of UPR-associated genes and proteins. Increased GRP78 and sXBP1 expression was found in experimental dry eye and Sjögren syndrome models and was GC specific. Increased GRP78 was also found in the conjunctiva of patients with Sjögren syndrome at the gene and protein levels. Treatment with dexamethasone inhibited expression of UPR-associated genes and increased mucin production. These results indicate that induction of UPR by IFN-γ is an important cause of GC-associated mucin deficiency observed in aqueous-deficient dry eye. Therapies to block the effects of IFN-γ on the metabolically active endoplasmic reticulum in these cells might enhance synthesis and secretion of the protective GC mucins on the ocular surface. PMID:27085137

  7. Surgical treatment of mucin-producing cholangiocarcinoma arising from intraductal papillary neoplasm of the intrahepatic bile duct: a report of 2 cases

    PubMed Central

    Baterdene, Namsrai; Lee, Jong-Wook; Jung, Min-Jae; Shin, Heeji; Seo, Hye Kyoung; Kim, Myeong-Hwan; Lee, Sung-Koo

    2016-01-01

    Intraductal papillary neoplasms of the bile duct (IPNB) leads to malignant transformation and mucin production. Herein, we presented two cases of mucin-producing IPNB with obstructive jaundice who underwent resection of the intrahepatic lesions and bypass hepaticojejunostomy. The first case was a 69 year-old male patient with 5-year follow up for gallstone disease. Imaging studies showed mucin-secreting IPNB mainly in the hepatic segment III bile duct (B3) and multiple intrahepatic duct stones for which, segment III resection, intrahepatic stone removal, end-to-side choledochojejunostomy and B3 hepaticojejunostomy were conducted. The second case was a 74 year-old female patient with 11-year follow up for gallstone disease. Imaging studies showed mucin-producing IPNB with dilatation of the segment IV duct (B4) and mural nodules for which, segment IV resection, partial resection of the diaphragm and central hepaticojejunostomy were conducted. Both patients recovered uneventfully from surgery. These cases highlight that in patients with IPNB, abundant production of highly viscous mucin inducing obstructive jaundice may be associated with malignant transformation. PMID:27621752

  8. Mechanosensitive ATP Release Maintains Proper Mucus Hydration of Airways

    PubMed Central

    Button, Brian; Okada, Seiko F.; Frederick, Charles Brandon; Thelin, William R.; Boucher, Richard C.

    2013-01-01

    The clearance of mucus from the airways protects the lungs from inhaled noxious and infectious materials. Proper hydration of the mucus layer enables efficient mucus clearance through beating of cilia on airway epithelial cells, and reduced clearance of excessively concentrated mucus occurs in patients with chronic obstructive pulmonary disease and cystic fibrosis. Key steps in the mucus transport process are airway epithelia sensing and responding to changes in mucus hydration. We reported that extracellular adenosine triphosphate (ATP) and adenosine were important luminal auto-crine and paracrine signals that regulated the hydration of the surface of human airway epithelial cultures through their action on apical membrane purinoceptors. Mucus hydration in human airway epithelial cultures was sensed by an interaction between cilia and the overlying mucus layer: Changes in mechanical strain, proportional to mucus hydration, regulated ATP release rates, adjusting fluid secretion to optimize mucus layer hydration. This system provided a feedback mechanism by which airways maintained mucus hydration in an optimum range for cilia propulsion. Understanding how airway epithelia can sense and respond to changes in mucus properties helps us to understand how the mucus clearance system protects the airways in health and how it fails in lung diseases such as cystic fibrosis. PMID:23757023

  9. Mechanosensitive ATP release maintains proper mucus hydration of airways.

    PubMed

    Button, Brian; Okada, Seiko F; Frederick, Charles Brandon; Thelin, William R; Boucher, Richard C

    2013-06-11

    The clearance of mucus from the airways protects the lungs from inhaled noxious and infectious materials. Proper hydration of the mucus layer enables efficient mucus clearance through beating of cilia on airway epithelial cells, and reduced clearance of excessively concentrated mucus occurs in patients with chronic obstructive pulmonary disease and cystic fibrosis. Key steps in the mucus transport process are airway epithelia sensing and responding to changes in mucus hydration. We reported that extracellular adenosine triphosphate (ATP) and adenosine were important luminal autocrine and paracrine signals that regulated the hydration of the surface of human airway epithelial cultures through their action on apical membrane purinoceptors. Mucus hydration in human airway epithelial cultures was sensed by an interaction between cilia and the overlying mucus layer: Changes in mechanical strain, proportional to mucus hydration, regulated ATP release rates, adjusting fluid secretion to optimize mucus layer hydration. This system provided a feedback mechanism by which airways maintained mucus hydration in an optimum range for cilia propulsion. Understanding how airway epithelia can sense and respond to changes in mucus properties helps us to understand how the mucus clearance system protects the airways in health and how it fails in lung diseases such as cystic fibrosis. PMID:23757023

  10. Oral N-acetylcysteine reduces bleomycin-induced lung damage and mucin Muc5ac expression in rats.

    PubMed

    Mata, M; Ruíz, A; Cerdá, M; Martinez-Losa, M; Cortijo, J; Santangelo, F; Serrano-Mollar, A; Llombart-Bosch, A; Morcillo, E J

    2003-12-01

    Oxidative stress is involved in the pathogenesis of pulmonary fibrosis, therefore antioxidants may be of therapeutic value. Clinical work indicates that N-acetylcysteine (NAC) may be beneficial in this disease. The activity of this antioxidant was examined on bleomycin-induced lung damage, mucus secretory cells hyperplasia and mucin Muc5ac gene expression in rats. NAC (3 mmol x kg(-1) x day(-1)) or saline was given orally to Sprague-Dawley rats for 1 week prior to a single intratracheal instillation of bleomycin (2.5 U x kg(-1)) and for 14 days postinstillation. NAC decreased collagen deposition in bleomycin-exposed rats (hydroxyproline content was 4,257+/-323 and 3,200+/-192 microg x lung(-1) in vehicle- and NAC-treated rats, respectively) and lessened the fibrotic area assessed by morphometric analysis. The bleomycin-induced increases in lung tumour necrosis factor-alpha and myeloperoxidase activity were reduced by NAC treatment. The numbers of mucus secretory cells in airway epithelium, and the Muc5ac messenger ribonucleic acid and protein expression, were markedly augmented in rats exposed to bleomycin. These changes were significantly reduced in NAC-treated rats. These results indicate that bleomycin increases the number of airway secretory cells and their mucin production, and that oral N-acetylcysteine improved pulmonary lesions and reduced the mucus hypersecretion in the bleomycin rat model. PMID:14680076

  11. Conquering the difficult airway.

    PubMed

    Gandy, William E

    2008-01-01

    Every medic should practice regularly for the inevitable difficult airway case. Practice should include review of the causes of difficult airways, as well as skill practice. Having a preassembled airway kit can make your response to an unexpected difficult situation easier. Of all the devices mentioned, the bougie is the airway practitioner's best friend. Using the BURP technique, if not contraindicated, together with the bougie will enable you to intubate many difficult patients with confidence. Remember, "If your patient cannot breathe, nothing else matters. PMID:18251307

  12. Penile mucinous carcinoma: A case report

    PubMed Central

    ÖZTÜRK, HAKAN

    2015-01-01

    Penile cancer is an extremely rare form of urological cancer that usually originates in the epithelium of the inner preputium or glans. Major etiological factors include phimosis, poor penile hygiene and smoking. Nearly 95% of penile cancers are squamous cell carcinomas and usually occur in the sixth decade of life. The disease exhibits two variants, namely metastatic and atypical disease. Squamous differentiation may also present with mucinous metaplasia. An extremely limited number of case reports on penile cancer are available in the literature. The present study reports the case of a 39-year-old patient with penile mucinous adenocarcinoma who was admitted with the complaint of perineal discharge, which is, to the best of our knowledge, the first case in the literature. The patient underwent total penectomy and inguinal lymph node dissection. The tumor was staged as T4N1M0, according to the European Association of Urology’s tumor-node-metastasis classification system. The patient was treated with pelvic radiotherapy and six cycles of systemic neoadjuvant chemotherapy with cisplatin and paclitaxel simultaneously, over a period of four months. After nine months of follow-up the patient succumbed to the disease due to widespread metastases. PMID:25663900

  13. Mucins Suppress Virulence Traits of Candida albicans

    PubMed Central

    Kavanaugh, Nicole L.; Zhang, Angela Q.; Nobile, Clarissa J.; Johnson, Alexander D.

    2014-01-01

    ABSTRACT Candida albicans is the most prevalent fungal pathogen of humans, causing a variety of diseases ranging from superficial mucosal infections to deep-seated systemic invasions. Mucus, the gel that coats all wet epithelial surfaces, accommodates C. albicans as part of the normal microbiota, where C. albicans resides asymptomatically in healthy humans. Through a series of in vitro experiments combined with gene expression analysis, we show that mucin biopolymers, the main gel-forming constituents of mucus, induce a new oval-shaped morphology in C. albicans in which a range of genes related to adhesion, filamentation, and biofilm formation are downregulated. We also show that corresponding traits are suppressed, rendering C. albicans impaired in forming biofilms on a range of different synthetic surfaces and human epithelial cells. Our data suggest that mucins can manipulate C. albicans physiology, and we hypothesize that they are key environmental signals for retaining C. albicans in the host-compatible, commensal state. PMID:25389175

  14. Surface Tension Gradient Driven Spreading on Aqueous Mucin Solutions: A Possible Route to Enhanced Pulmonary Drug Delivery

    PubMed Central

    Koch, Kevin; Dew, Beautia; Corcoran, Timothy E.; Przybycien, Todd M.; Tilton, Robert D.; Garoff, Stephen

    2011-01-01

    Surface tension gradient driven, or “Marangoni,” flow can be used to move exogenous fluid, either surfactant dispersions or drug carrying formulations, through the lung. In this paper, we investigate the spreading of aqueous solutions of water-soluble surfactants over entangled, aqueous mucin solutions that mimic the airway surface liquid of the lung. We measure the movement of the formulation by incorporating dyes into the formulation while we measure surface flows of the mucin solution subphase using tracer particles. Surface tension forces and/or Marangoni stresses initiate a convective spreading flow over this rheologically complex subphase. As expected, when the concentration of surfactant is reduced until its surface tension is above that of the mucin solution, the convective spreading does not occur. The convective spreading front moves ahead of the drop containing the formulation. Convective spreading ends with the solution confined to a well-defined static area which must be governed by a surface tension balance. Further motion of the spread solution progresses by much slower diffusive processes. Spreading behaviors are qualitatively similar for formulations based on anionic, cationic, or nonionic surfactants, containing either hydrophilic or hydrophobic dyes, on mucin as well as on other entangled aqueous polymer solution subphases. This independence of qualitative spreading behaviors from the chemistry of the surfactant and subphase indicates that there is little chemical interaction between the formulation and the subphase during the spreading process. The spreading and final solution distributions are controlled by capillary and hydrodynamic phenomena and not by specific chemical interactions among the components of the system. It is suggested that capillary forces and Marangoni flows driven by soluble surfactants may thereby enhance the uniformity of drug delivery to diseased lungs. PMID:21250745

  15. A short-term ingestion of fructo-oligosaccharides increases immunoglobulin A and mucin concentrations in the rat cecum, but the effects are attenuated with the prolonged ingestion.

    PubMed

    Komura, Mika; Fukuta, Tomonori; Genda, Tomomi; Hino, Shingo; Aoe, Seiichiro; Kawagishi, Hirokazu; Morita, Tatsuya

    2014-01-01

    We examined the effects of fructo-oligosaccharides (FOS) on IgA and mucin secretion in the rat cecum after different ingestion periods. Rats were fed a control diet or a diet containing FOS for 1, 2, 4, and 8 wk. FOS ingestion greatly increased IgA and mucin concentrations at 1 and 2 wk, but the effects were disappeared or attenuated at 4 and 8 wk. After 1 wk, FOS induced higher lactobacilli and lactate concentrations and lower cecal pH in the cecum, but the alterations were moderated with the prolonged ingestion accompanying with increasing short-chain fatty acid concentrations. At 1 and 2 wk, FOS increased IgA plasma cells and polymeric immunoglobulin receptor expression in the cecal mucosa and strongly depressed fecal mucinase activities related to the lower cecal pH. These findings may explain the FOS-induced early elevation of IgA and mucin. Clearly, FOS effects on IgA and mucin secretion considerably differ depending on the ingestion period. PMID:25209509

  16. Brachycephalic airway syndrome: management.

    PubMed

    Lodato, Dena L; Hedlund, Cheryl S

    2012-08-01

    Brachycephalic airway syndrome (BAS) is a group of primary and secondary abnormalities that result in upper airway obstruction. Several of these abnormalities can be addressed medically and/or surgically to improve quality of life. This article reviews potential complications, anesthetic considerations, recovery strategies, and outcomes associated with medical and surgical management of BAS. PMID:22935992

  17. Simvastatin Inhibits Airway Hyperreactivity

    PubMed Central

    Zeki, Amir A.; Franzi, Lisa; Last, Jerold; Kenyon, Nicholas J.

    2009-01-01

    Rationale: Statin use has been linked to improved lung health in asthma and chronic obstructive pulmonary disease. We hypothesize that statins inhibit allergic airway inflammation and reduce airway hyperreactivity via a mevalonate-dependent mechanism. Objectives: To determine whether simvastatin attenuates airway inflammation and improves lung physiology by mevalonate pathway inhibition. Methods: BALB/c mice were sensitized to ovalbumin over 4 weeks and exposed to 1% ovalbumin aerosol over 2 weeks. Simvastatin (40 mg/kg) or simvastatin plus mevalonate (20 mg/kg) was injected intraperitoneally before each ovalbumin exposure. Measurements and Main Results: Simvastatin reduced total lung lavage leukocytes, eosinophils, and macrophages (P < 0.05) in the ovalbumin-exposed mice. Cotreatment with mevalonate, in addition to simvastatin, reversed the antiinflammatory effects seen with simvastatin alone (P < 0.05). Lung lavage IL-4, IL-13, and tumor necrosis factor-α levels were all reduced by treatment with simvastatin (P < 0.05). Simvastatin treatment before methacholine bronchial challenge increased lung compliance and reduced airway hyperreactivity (P = 0.0001). Conclusions: Simvastatin attenuates allergic airway inflammation, inhibits key helper T cell type 1 and 2 chemokines, and improves lung physiology in a mouse model of asthma. The mevalonate pathway appears to modulate allergic airway inflammation, while the beneficial effects of simvastatin on lung compliance and airway hyperreactivity may be independent of the mevalonate pathway. Simvastatin and similar agents that modulate the mevalonate pathway may prove to be treatments for inflammatory airway diseases, such as asthma. PMID:19608720

  18. Controversies in Pediatric Perioperative Airways

    PubMed Central

    Klučka, Jozef; Štourač, Petr; Štoudek, Roman; Ťoukálková, Michaela; Harazim, Hana; Kosinová, Martina

    2015-01-01

    Pediatric airway management is a challenge in routine anesthesia practice. Any airway-related complication due to improper procedure can have catastrophic consequences in pediatric patients. The authors reviewed the current relevant literature using the following data bases: Google Scholar, PubMed, Medline (OVID SP), and Dynamed, and the following keywords: Airway/s, Children, Pediatric, Difficult Airways, and Controversies. From a summary of the data, we identified several controversies: difficult airway prediction, difficult airway management, cuffed versus uncuffed endotracheal tubes for securing pediatric airways, rapid sequence induction (RSI), laryngeal mask versus endotracheal tube, and extubation timing. The data show that pediatric anesthesia practice in perioperative airway management is currently lacking the strong evidence-based medicine (EBM) data that is available for adult subpopulations. A number of procedural steps in airway management are derived only from adult populations. However, the objective is the same irrespective of patient age: proper securing of the airway and oxygenation of the patient. PMID:26759809

  19. Mucin glycan foraging in the human gut microbiome

    PubMed Central

    Tailford, Louise E.; Crost, Emmanuelle H.; Kavanaugh, Devon; Juge, Nathalie

    2015-01-01

    The availability of host and dietary carbohydrates in the gastrointestinal (GI) tract plays a key role in shaping the structure-function of the microbiota. In particular, some gut bacteria have the ability to forage on glycans provided by the mucus layer covering the GI tract. The O-glycan structures present in mucin are diverse and complex, consisting predominantly of core 1-4 mucin-type O-glycans containing α- and β- linked N-acetyl-galactosamine, galactose and N-acetyl-glucosamine. These core structures are further elongated and frequently modified by fucose and sialic acid sugar residues via α1,2/3/4 and α2,3/6 linkages, respectively. The ability to metabolize these mucin O-linked oligosaccharides is likely to be a key factor in determining which bacterial species colonize the mucosal surface. Due to their proximity to the immune system, mucin-degrading bacteria are in a prime location to influence the host response. However, despite the growing number of bacterial genome sequences available from mucin degraders, our knowledge on the structural requirements for mucin degradation by gut bacteria remains fragmented. This is largely due to the limited number of functionally characterized enzymes and the lack of studies correlating the specificity of these enzymes with the ability of the strain to degrade and utilize mucin and mucin glycans. This review focuses on recent findings unraveling the molecular strategies used by mucin-degrading bacteria to utilize host glycans, adapt to the mucosal environment, and influence human health. PMID:25852737

  20. Ovarian mucinous tumor with malignant mural nodules: dedifferentiation or collision?

    PubMed

    Desouki, Mohamed M; Khabele, Dineo; Crispens, Marta A; Fadare, Oluwole

    2015-01-01

    Ovarian mucinous tumors with mural nodules are rare surface epithelial-stromal tumors. The mural nodules are divergent neoplasms that may be benign or malignant. The latter may be in the form of a sarcoma, carcinosarcoma, anaplastic carcinoma, or a variety of other recognized histotypes of carcinoma, which raises the question of whether malignant mural nodules represent a form of dedifferentiation in ovarian mucinous tumors or whether they represent collision tumors. We recently reported the K-RAS gene mutation status in a case of ovarian mucinous adenocarcinoma with mural nodule of high-grade sarcoma. The mucinous and sarcomatous components revealed a mutation in codon 12 of the K-RAS gene of a different nucleotide substitution, indicating that these 2 tumor components were different clones of the same tumor. Herein, we are reporting another case of a 20-yr-old woman who presented with 22 cm pelvic mass, omental caking, and ascites. A diagnosis of invasive mucinous carcinoma with mural nodules of anaplastic carcinoma was rendered. K-RAS gene mutation studies revealed p.G12V, c.35G>T mutation in the 2 components of the tumor, which is the most common mutation reported in mucinous tumors of the ovary. The fact that sarcomatous or anaplastic carcinomatous mural nodules in ovarian mucinous tumors display the same K-RAS mutations as their underlying mucinous neoplasms provides supportive evidence that at least some malignant mural nodules represent a form of dedifferentiation in ovarian mucinous tumors, rather than a collision of 2 divergent tumor types. PMID:25473748

  1. Mucin glycan foraging in the human gut microbiome.

    PubMed

    Tailford, Louise E; Crost, Emmanuelle H; Kavanaugh, Devon; Juge, Nathalie

    2015-01-01

    The availability of host and dietary carbohydrates in the gastrointestinal (GI) tract plays a key role in shaping the structure-function of the microbiota. In particular, some gut bacteria have the ability to forage on glycans provided by the mucus layer covering the GI tract. The O-glycan structures present in mucin are diverse and complex, consisting predominantly of core 1-4 mucin-type O-glycans containing α- and β- linked N-acetyl-galactosamine, galactose and N-acetyl-glucosamine. These core structures are further elongated and frequently modified by fucose and sialic acid sugar residues via α1,2/3/4 and α2,3/6 linkages, respectively. The ability to metabolize these mucin O-linked oligosaccharides is likely to be a key factor in determining which bacterial species colonize the mucosal surface. Due to their proximity to the immune system, mucin-degrading bacteria are in a prime location to influence the host response. However, despite the growing number of bacterial genome sequences available from mucin degraders, our knowledge on the structural requirements for mucin degradation by gut bacteria remains fragmented. This is largely due to the limited number of functionally characterized enzymes and the lack of studies correlating the specificity of these enzymes with the ability of the strain to degrade and utilize mucin and mucin glycans. This review focuses on recent findings unraveling the molecular strategies used by mucin-degrading bacteria to utilize host glycans, adapt to the mucosal environment, and influence human health. PMID:25852737

  2. Expression profile of mucins in ovarian mucinous tumors: distinguishing primary ovarian from metastatic tumors.

    PubMed

    Wang, Jayson; El-Bahrawy, Mona A

    2014-03-01

    Ovarian mucinous tumors (OMTs) of the intestinal type share morphologic features with primary tumors of other sites, and it can often be difficult to distinguish primary ovarian from metastatic mucinous tumors. MUC1, MUC2, MUC5AC, and MUC6 expressions were studied by immunohistochemistry in 36 OMTs of intestinal type (17 malignant, 19 borderline), 18 pancreatic, 12 biliary, 15 esophageal, 9 gastric, and 7 colorectal/appendiceal adenocarcinomas. All samples were from primary sites, except for colorectal tumors which were from ovarian metastases. Borderline and malignant OMTs show similar mucin immunoprofile, being strongly and uniformly positive for MUC5AC (97.2% of cases), whereas only focally positive for MUC1 (19.4%), MUC2 (38.9%), and MUC6 (22.2%). The positive frequencies of pancreatic adenocarcinomas for MUC1, MUC2, MUC5AC, and MUC6, respectively, were 100%, 16.7%, 94.4%, and 61.1%; for biliary (cholangiocarcinomas) were 91.7%, 0%, 16.7%, and 8.3%; for esophageal carcinomas were 73.3%, 33.3%, 53.3%, and 26.7%; for gastric carcinomas were 44.4%, 44.4%, 44.4%, and 0% and for lower gastrointestinal tract cancers were 28.6%, 85.7%, 42.9%, and 0%. Our study shows that OMTs are usually MUC5AC+/MUC1-, which is different from pancreatic, biliary, esophageal, gastric, and colorectal/appendiceal carcinomas. We recommend that these mucin stains be added to the panel of immunostains to differentiate metastatic tumors to the ovary from primary OMTs. PMID:24487472

  3. Mechanisms of BDNF regulation in asthmatic airway smooth muscle.

    PubMed

    Aravamudan, Bharathi; Thompson, Michael A; Pabelick, Christina M; Prakash, Y S

    2016-08-01

    Brain-derived neurotrophic factor (BDNF), a neurotrophin produced by airway smooth muscle (ASM), enhances inflammation effects on airway contractility, supporting the idea that locally produced growth factors influence airway diseases such as asthma. We endeavored to dissect intrinsic mechanisms regulating endogenous, as well as inflammation (TNF-α)-induced BDNF secretion in ASM of nonasthmatic vs. asthmatic humans. We focused on specific Ca(2+) regulation- and inflammation-related signaling cascades and quantified BDNF secretion. We find that TNF-α enhances BDNF release by ASM cells, via several mechanisms relevant to asthma, including transient receptor potential channels TRPC3 and TRPC6 (but not TRPC1), ERK 1/2, PI3K, PLC, and PKC cascades, Rho kinase, and transcription factors cAMP response element binding protein and nuclear factor of activated T cells. Basal BDNF expression and secretion are elevated in asthmatic ASM and increase further with TNF-α exposure, involving many of these regulatory mechanisms. We conclude that airway BDNF secretion is regulated at multiple levels, providing a basis for autocrine effects of BDNF under conditions of inflammation and disease, with potential downstream influences on contractility and remodeling. PMID:27317689

  4. Transcriptional PROFILING OF MUCOCILIARY DIFFERENTIATION IN HUMAN AIRWAY EPITHELIAL CELLS

    EPA Science Inventory

    When cultured at an air-liquid interface (ALI) in the appropriate medium, primary human airway epithelial cells form a polarized, pseudostratified epithelium composed of ciliated and mucus-secreting cells. This culture system provides a useful tool for the in vitro study of...

  5. Identification of a Novel Mucin Gene HCG22 Associated With Steroid-Induced Ocular Hypertension

    PubMed Central

    Jeong, Shinwu; Patel, Nitin; Edlund, Christopher K.; Hartiala, Jaana; Hazelett, Dennis J.; Itakura, Tatsuo; Wu, Pei-Chang; Avery, Robert L.; Davis, Janet L.; Flynn, Harry W.; Lalwani, Geeta; Puliafito, Carmen A.; Wafapoor, Hussein; Hijikata, Minako; Keicho, Naoto; Gao, Xiaoyi; Argüeso, Pablo; Allayee, Hooman; Coetzee, Gerhard A.; Pletcher, Mathew T.; Conti, David V.; Schwartz, Stephen G.; Eaton, Alexander M.; Fini, M. Elizabeth

    2015-01-01

    Purpose. The pathophysiology of ocular hypertension (OH) leading to primary open-angle glaucoma shares many features with a secondary form of OH caused by treatment with glucocorticoids, but also exhibits distinct differences. In this study, a pharmacogenomics approach was taken to discover candidate genes for this disorder. Methods. A genome-wide association study was performed, followed by an independent candidate gene study, using a cohort enrolled from patients treated with off-label intravitreal triamcinolone, and handling change in IOP as a quantitative trait. Results. An intergenic quantitative trait locus (QTL) was identified at chromosome 6p21.33 near the 5′ end of HCG22 that attained the accepted statistical threshold for genome-level significance. The HCG22 transcript, encoding a novel mucin protein, was expressed in trabecular meshwork cells, and expression was stimulated by IL-1, and inhibited by triamcinolone acetate and TGF-β. Bioinformatic analysis defined the QTL as an approximately 4 kilobase (kb) linkage disequilibrium block containing 10 common single nucleotide polymorphisms (SNPs). Four of these SNPs were identified in the National Center for Biotechnology Information (NCBI) GTEx eQTL browser as modifiers of HCG22 expression. Most are predicted to disrupt or improve motifs for transcription factor binding, the most relevant being disruption of the glucocorticoid receptor binding motif. A second QTL was identified within the predicted signal peptide of the HCG22 encoded protein that could affect its secretion. Translation, O-glycosylation, and secretion of the predicted HCG22 protein was verified in cultured trabecular meshwork cells. Conclusions. Identification of two independent QTLs that could affect expression of the HCG22 mucin gene product via two different mechanisms (transcription or secretion) is highly suggestive of a role in steroid-induced OH. PMID:25813999

  6. Mucinous ovarian tumors associated with mucinous adenocarcinomas of the cervix. A clinicopathological analysis of 16 cases.

    PubMed

    Young, R H; Scully, R E

    1988-01-01

    Sixteen cases of mucinous adenocarcinoma of the cervix that were associated with a mucinous tumor of one or both ovaries are reported. The patients ranged from 25 to 70 (average, 44) years of age; two of them had the Peutz-Jeghers syndrome. Eight patients complained of abdominal swelling; most of the remainder had symptoms of uterine origin. Twelve patients had bilateral and four had unilateral ovarian tumors, which were typically large and cystic. Microscopic examination of most of the ovarian tumors revealed various combinations of benign-appearing, borderline, and carcinomatous mucinous epithelium within the same specimen. Most of the cervical tumors were deeply invasive; 10 of them were of the adenoma malignum type. Although there were varying degrees of uncertainty in individual cases, consideration of several features including the extent and distribution of disease in the abdomen, the comparative histology of the tumors, and the pattern of ovarian involvement suggested that 10 of the ovarian tumors were independent primary tumors, three were metastatic from the cervix, and in three cases the ovaries contained both primary and metastatic tumors. PMID:2840404

  7. Effect of Perinatal secondhand tobacco smoke exposure on in vivo and intrinsic airway structure/function in non-human primates

    SciTech Connect

    Joad, Jesse P. Kott, Kayleen S.; Bric, John M.; Peake, Janice L.; Pinkerton, Kent E.

    2009-02-01

    Infants exposed to second hand smoke (SHS) experience more problems with wheezing. This study was designed to determine if perinatal SHS exposure increases intrinsic and/or in vivo airway responsiveness to methacholine and whether potential structural/cellular alterations in the airway might explain the change in responsiveness. Pregnant rhesus monkeys were exposed to filtered air (FA) or SHS (1 mg/m{sup 3} total suspended particulates) for 6 h/day, 5 days/week starting at 50 days gestational age. The mother/infant pairs continued the SHS exposures postnatally. At 3 months of age each infant: 1) had in vivo lung function measurements in response to inhaled methacholine, or 2) the right accessory lobe filled with agarose, precision-cut to 600 {mu}m slices, and bathed in increasing concentrations of methacholine. The lumenal area of the central airway was determined using videomicrometry followed by fixation and histology with morphometry. In vivo tests showed that perinatal SHS increases baseline respiratory rate and decreases responsiveness to methacholine. Perinatal SHS did not alter intrinsic airway responsiveness in the bronchi. However in respiratory bronchioles, SHS exposure increased airway responsiveness at lower methacholine concentrations but decreased it at higher concentrations. Perinatal SHS did not change eosinophil profiles, epithelial volume, smooth muscle volume, or mucin volume. However it did increase the number of alveolar attachments in bronchi and respiratory bronchioles. In general, as mucin increased, airway responsiveness decreased. We conclude that perinatal SHS exposure alters in vivo and intrinsic airway responsiveness, and alveolar attachments.

  8. Effect of perinatal secondhand tobacco smoke exposure on in vivo and intrinsic airway structure/function in non-human primates.

    PubMed

    Joad, Jesse P; Kott, Kayleen S; Bric, John M; Peake, Janice L; Pinkerton, Kent E

    2009-02-01

    Infants exposed to second hand smoke (SHS) experience more problems with wheezing. This study was designed to determine if perinatal SHS exposure increases intrinsic and/or in vivo airway responsiveness to methacholine and whether potential structural/cellular alterations in the airway might explain the change in responsiveness. Pregnant rhesus monkeys were exposed to filtered air (FA) or SHS (1 mg/m(3) total suspended particulates) for 6 h/day, 5 days/week starting at 50 days gestational age. The mother/infant pairs continued the SHS exposures postnatally. At 3 months of age each infant: 1) had in vivo lung function measurements in response to inhaled methacholine, or 2) the right accessory lobe filled with agarose, precision-cut to 600 mum slices, and bathed in increasing concentrations of methacholine. The lumenal area of the central airway was determined using videomicrometry followed by fixation and histology with morphometry. In vivo tests showed that perinatal SHS increases baseline respiratory rate and decreases responsiveness to methacholine. Perinatal SHS did not alter intrinsic airway responsiveness in the bronchi. However in respiratory bronchioles, SHS exposure increased airway responsiveness at lower methacholine concentrations but decreased it at higher concentrations. Perinatal SHS did not change eosinophil profiles, epithelial volume, smooth muscle volume, or mucin volume. However it did increase the number of alveolar attachments in bronchi and respiratory bronchioles. In general, as mucin increased, airway responsiveness decreased. We conclude that perinatal SHS exposure alters in vivo and intrinsic airway responsiveness, and alveolar attachments. PMID:19084550

  9. Impairment of Salivary Mucin Production Resulting in Declined Salivary Viscosity During Naproxen Administration as a Potential Link to Upper Alimentary Tract Mucosal Injury

    PubMed Central

    Garcia, Cesar J; Castro-Combs, Juan; Dias, Ajoy; Alfaro, Rodrigo; Vasallo, Javier; Majewski, Marek; Jaworski, Tom; Wallner, Grzegorz; Sarosiek, Jerzy

    2013-01-01

    OBJECTIVES: Nonsteroidal anti-inflammatory drugs (NSAIDs) contribute to the esophageal mucosal injury through its direct topical impact on the luminal aspect of the surface epithelium. Its indirect, systemic impact, however, on salivary component of the esophageal pre-epithelial barrier remains to be explored. Therefore, salivary mucin secretion and viscosity at baseline and during naproxen-placebo, as well as naproxen-rabeprazole, administration were investigated. METHODS: Twenty-one asymptomatic volunteers were included in this double-blind, placebo-controlled, crossover designed study. Salivary samples were obtained in basal and pentagastrin-stimulated conditions (6 mg/kg s.c.) mimicking the food-stimulated conditions. Patients received 7 days of naproxen-placebo or naproxen-rabeprazole with a 2-week washout period in between. Salivary mucin content and viscosity were measured before and after treatment using periodic acid/Schiff's methodology and Cone/Plate Digital Viscometer, respectively. RESULTS: The rate of salivary mucin secretion in basal condition declined by 32% during administration of naproxen-placebo (11.3±1.7 vs. 16.8±3.3 mg/h). Salivary mucin secretion in pentagastrin-stimulated condition declined significantly (by 34%) during the administration of naproxen-placebo (13.6±1.5 vs. 20.7±3.0 mg/h; P<0.05). Viscosity significantly decreased after naproxen-placebo administration in basal (by 60%) and stimulated conditions (by 56%) (P<0.001). Coadministration of rabeprazole at least partly restored the naproxen-induced decline of salivary mucin in basal condition (by 8%), and pentagastrin-stimulated conditions (by 30%). CONCLUSIONS: A significant decline of salivary mucin and viscosity during administration of naproxen may at least partly explain a propensity of patients on chronic therapy with NSAIDs to the development of esophageal mucosal injury and complications. In addition the trend to restorative capacity of rabeprazole on the

  10. Airway epithelial cell responses to ozone injury

    SciTech Connect

    Leikauf, G.D.; Simpson, L.G.; Zhao, Qiyu

    1995-03-01

    The airway epithelial cell is an important target in ozone injury. Once activated, the airway epithelium responds in three phases. The initial, or immediate phase, involves activation of constitutive cells, often through direct covalent interactions including the formation of secondary ozonolysis products-hydroxyhydroperoxides, aldehydes, and hydrogen peroxide. Recently, we found hydroxyhydroperoxides to be potent agonists; of bioactive eicosanoid formation by human airway epithelial cells in culture. Other probable immediate events include activation and inactivation of enzymes present on the epithelial surface (e.g., neutral endopeptidase). During the next 2 to 24 hr, or early phase, epithelial cells respond by synthesis and release of chemotactic factors, including chemokines-macrophage inflammatory protein-2, RANTES, and interleukin-8. Infiltrating leukocytes during this period also release elastase, an important agonist of epithelial cell mucus secretion and additional chemokine formation. The third (late) phase of ozone injury is characterized by eosinophil or monocyte infiltration. Cytokine expression leads to alteration of structural protein synthesis, with increases in fibronectin evident by in situ hybridization. Synthesis of epithelial antiproteases, e.g., secretary leukocyte protease inhibitor, may also increase locally 24 to 48 hr after elastase concentrations become excessive. Thus, the epithelium is not merely a passive barrier to ozone injury but has a dynamic role in directing the migration, activating, and then counteracting inflammatory cells. Through these complex interactions, epithelial cells can be viewed as the initiators (alpha) and the receptors (omega) of ozone-induced airway disease. 51 refs., 2 figs., 3 tabs.

  11. Role of Extracellular Transaldolase from Bifidobacterium bifidum in Mucin Adhesion and Aggregation

    PubMed Central

    González-Rodríguez, Irene; Sánchez, Borja; Ruiz, Lorena; Turroni, Francesca; Ventura, Marco; Ruas-Madiedo, Patricia; Gueimonde, Miguel

    2012-01-01

    The ability of bifidobacteria to establish in the intestine of mammals is among the main factors considered to be important for achieving probiotic effects. The role of surface molecules from Bifidobacterium bifidum taxon in mucin adhesion capability and the aggregation phenotype of this bacterial species was analyzed. Adhesion to the human intestinal cell line HT29 was determined for a collection of 12 B. bifidum strains. In four of them—B. bifidum LMG13195, DSM20456, DSM20239, and A8—the involvement of surface-exposed macromolecules in the aggregation phenomenon was determined. The aggregation of B. bifidum A8 and DSM20456 was abolished after treatment with proteinase K, this effect being more pronounced for the strain A8. Furthermore, a mucin binding assay of B. bifidum A8 surface proteins showed a high adhesive capability for its transaldolase (Tal). The localization of this enzyme on the surface of B. bifidum A8 was unequivocally demonstrated by immunogold electron microscopy experiments. The gene encoding Tal from B. bifidum A8 was expressed in Lactococcus lactis, and the protein was purified to homogeneity. The pure protein was able to restore the autoaggregation phenotype of proteinase K-treated B. bifidum A8 cells. A recombinant L. lactis strain, engineered to secrete Tal, displayed a mucin- binding level more than three times higher than the strain not producing the transaldolase. These findings suggest that Tal, when exposed on the cell surface of B. bifidum, could act as an important colonization factor favoring its establishment in the gut. PMID:22447584

  12. Regulation of Cl^- Channels in Normal and Cystic Fibrosis Airway Epithelial Cells by Extracellular ATP

    NASA Astrophysics Data System (ADS)

    Stutts, M. J.; Chinet, T. C.; Mason, S. J.; Fullton, J. M.; Clarke, L. L.; Boucher, R. C.

    1992-03-01

    The rate of Cl^- secretion by human airway epithelium is determined, in part, by apical cell membrane Cl^- conductance. In cystic fibrosis airway epithelia, defective regulation of Cl^- conductance decreases the capability to secrete Cl^-. Here we report that extracytosolic ATP in the luminal bath of cultured human airway epithelia increased transepithelial Cl^- secretion and apical membrane Cl^- permeability. Single-channel studies in excised membrane patches revealed that ATP increased the open probability of outward rectifying Cl^- channels. The latter effect occurs through a receptor mechanism that requires no identified soluble second messengers and is insensitive to probes of G protein function. These results demonstrate a mode of regulation of anion channels by binding ATP at the extracellular surface. Regulation of Cl^- conductance by external ATP is preserved in cystic fibrosis airway epithelia.

  13. Mucin-Type O-Glycosylation in Gastric Carcinogenesis.

    PubMed

    Duarte, Henrique O; Freitas, Daniela; Gomes, Catarina; Gomes, Joana; Magalhães, Ana; Reis, Celso A

    2016-01-01

    Mucin-type O-glycosylation plays a crucial role in several physiological and pathological processes of the gastric tissue. Modifications in enzymes responsible for key glycosylation steps and the consequent abnormal biosynthesis and expression of their glycan products constitute well-established molecular hallmarks of disease state. This review addresses the major role played by mucins and associated O-glycan structures in Helicobacter pylori adhesion to the gastric mucosa and the subsequent establishment of a chronic infection, with concomitant drastic alterations of the gastric epithelium glycophenotype. Furthermore, alterations of mucin expression pattern and glycan signatures occurring in preneoplastic lesions and in gastric carcinoma are also described, as well as their impact throughout the gastric carcinogenesis cascade and in cancer progression. Altogether, mucin-type O-glycosylation alterations may represent promising biomarkers with potential screening and prognostic applications, as well as predictors of cancer patients' response to therapy. PMID:27409642

  14. Airway dysfunction in swimmers.

    PubMed

    Bougault, Valérie; Boulet, Louis-Philippe

    2012-05-01

    Elite competitive swimmers are particularly affected by airway disorders that are probably related to regular and intense training sessions in a chlorinated environment. Upper and lower airway respiratory symptoms, rhinitis, airway hyper-responsiveness, and exercise-induced bronchoconstriction are highly prevalent in these athletes, but their influence on athletic performance is still unclear. The authors reviewed the main upper and lower respiratory ailments observed in competitive swimmers who train in indoor swimming pools, their pathophysiology, clinical significance and possible effects on performance. Issues regarding the screening of these disorders, their management and preventive measures are addressed. PMID:22247299

  15. Meteorological conditions along airways

    NASA Technical Reports Server (NTRS)

    Gregg, W R

    1927-01-01

    This report is an attempt to show the kind of meteorological information that is needed, and is in part available, for the purpose of determining operating conditions along airways. In general, the same factors affect these operating conditions along all airways though in varying degree, depending upon their topographic, geographic, and other characteristics; but in order to bring out as clearly as possible the nature of the data available, a specific example is taken, that of the Chicago-Dallas airway on which regular flying begins this year (1926).

  16. Antiviral activity of purified human breast milk mucin.

    PubMed

    Habte, Habtom H; Kotwal, Girish J; Lotz, Zoë E; Tyler, Marilyn G; Abrahams, Melissa; Rodriques, Jerry; Kahn, Delawir; Mall, Anwar S

    2007-01-01

    Human breast milk is known to contain numerous biologically active components which protect breast fed infants against microbes, viruses, and toxins. The purpose of this study was to purify and characterize the breast milk mucin and determine its anti-poxvirus activity. In this study human milk mucin, free of contaminant protein and of sufficient quantity for further analysis, was isolated and purified by Sepharose CL-4B gel filtration and cesiumchloride density-gradient centrifugation. Based on the criteria of size and appearance of the bands and their electrophoretic mobility on sodium dodecyl sulfate polyacrylamide-gel electrophoresis, Western blotting together with the amino acid analysis, it is very likely that the human breast milk mucin is MUC1. It was shown that this breast milk mucin inhibits poxvirus activity by 100% using an inhibition assay with a viral concentration of 2.4 million plaque-forming units/ml. As the milk mucin seems to aggregate poxviruses prior to their entry into host cells, it is possible that this mucin may also inhibit other enveloped viruses such as HIV from entry into host cells. PMID:17361093

  17. Mucinous adenocarcinoma of the renal pelvis with pseudomyxoma peritonei.

    PubMed

    Shah, Vinaya B; Amonkar, Gayathri P; Deshpande, Jaya R; Bhalekar, Hemant

    2008-01-01

    Mucinous adenocarcinoma of the renal pelvis is an extremely rare tumor with very few case reports in literature. Pseudomyxoma peritonei is an uncommon condition characterized by the presence of mucinous gelatinous material in the peritoneal cavity. It occurs secondary to primary mucinous neoplasms of particularly the appendix and the ovary. We present a case of a 35-year-old female who had a history of dull aching pain in the right flank since one and a half years. Upon ultrasonography (USG) and computerized tomography (CT) scan, there was a large cystic mass measuring 15x15x12 cm, extending into the right lumbar region. Grossly, the entire kidney was converted into a cystic mass measuring 15x15x12 cm containing gelatinous mucinous material weighing 1 kg. Histologically, the tumor was composed of simple and complex glandular acini together with a superficial resemblance to colonic mucosa with abundant extracellular mucin. Thus, a diagnosis of mucinous adenocarcinoma of the renal pelvis leading to pseudomyxoma peritonei was made. PMID:19008588

  18. A mucin-like peptide from Fasciola hepatica induces parasite-specific Th1-type cell immunity.

    PubMed

    Noya, Verónica; Brossard, Natalie; Berasaín, Patricia; Rodríguez, Ernesto; Chiale, Carolina; Mazal, Daniel; Carmona, Carlos; Freire, Teresa

    2016-03-01

    Fasciolosis, caused by the liver fluke Fasciola hepatica, is a major parasitic disease of livestock that causes significant economic losses worldwide. Although drugs are effective against liver flukes, they do not prevent reinfection, and continuous treatment is costly. Moreover, resistant fluke strains are emerging. In this context, vaccination is a good alternative since it provides a cost-effective long-term prevention strategy to control fasciolosis. In this paper, we evaluate the Fhmuc peptide as a potential vaccine against fasciolosis. This peptide derives from a mucin-like protein highly expressed in the infective stage of Fasciola hepatica. Mucin-like molecules expressed by parasites can contribute to several infection processes by protecting the parasite from host proteases and recognition by the immune system. We show that the Fhmuc peptide induces Th1-like immune responses specific for F. hepatica excretion-secretion products (FhESP) with a high production of IFNγ. We also investigated whether this peptide could protect animals from infection, and present preliminary data indicating that animals treated with Fhmuc exhibited reduced liver damage compared to non-immunised animals and that this protection was associated with a recruitment of B and T lymphocytes in the peritoneum, as well as eosinophils and mature dendritic cells. These results suggest that the mucin-like peptide Fhmuc could constitute a potential vaccine candidate against fasciolosis and pave the way towards the development of vaccines against parasites. PMID:26637311

  19. Bradykinin metabolism in rat and sheep nasal secretions.

    PubMed

    Chung, F Y; Donovan, M D

    1995-07-01

    The nasal secretions are the first barrier that nasally administered drugs encounter. Therefore, the characterization of peptide metabolism in the nasal secretions is essential to predict nasal peptide bioavailability. Metabolism of bradykinin was measured in rat and sheep nasal secretions to estimate the extent of degradation of nasally administered peptide compounds. A single-pass, in situ nasal perfusion technique was employed to collect secretions for the investigation of peptide metabolism in rat nasal secretions. The protein content, mucin concentration, and degree of bradykinin metabolism in perfusate aliquots collected over a 2-h period showed that the early perfusate fractions contained most of the active secretory materials. Evidence of continuous mucus secretion and plasma extravasation was found in the nasal perfusate throughout the entire collection period. Sheep nasal secretions were collected with a cotton pledget inserted into the nasal cavity. Bradykinin and its fragments were degraded by carboxypeptidases and endopeptidases present in both rat and sheep nasal secretions. Hydrolysis of Phe5-Ser6 was the major metabolism pathway of bradykinin in the rat nasal perfusate, whereas in sheep nasal secretions, hydrolysis of the Pro7-Phe8 and Phe8-Arg9 bonds also occurred. Evidence of angiotensin converting enzyme, carboxypeptide N, and aminopeptidase activity was identified in the rat nasal perfusate with specific substrates and inhibitors. The activity of these and other enzymes in the nasal secretions may significantly limit the bioavailability of nasally administered peptide drugs prior to their exposure to the nasal mucosal tissues. PMID:7562432

  20. Airway management in trauma.

    PubMed

    Langeron, O; Birenbaum, A; Amour, J

    2009-05-01

    Maintenance of a patent and prevention of aspiration are essential for the management of the trauma patient, that requires experienced physicians in airway control techniques. Difficulties of the airway control in the trauma setting are increased by the vital failures, the risk of aspiration, the potential cervical spine injury, the combative patient, and the obvious risk of difficult tracheal intubation related to specific injury related to the trauma. Endotracheal intubation remains the gold standard in trauma patient airway management and should be performed via the oral route with a rapid sequence induction and a manual in-line stabilization maneuver, to decrease the risks previously mentioned. Different techniques to control the airway in trauma patients are presented: improvement of the laryngoscopic vision, lighted stylet tracheal intubation, retrograde technique for orotracheal intubation, the laryngeal mask and the intubating laryngeal mask airways, the combitube and cricothyroidotomy. Management of the airway in trauma patients requires regular training in these techniques and the knowledge of complementary techniques allowing tracheal intubation or oxygenation to overcome difficult intubation and to prevent major complications as hypoxemia and aspiration. PMID:19412149

  1. The effects of inhaled corticosteroids on intrinsic responsiveness and histology of airways from infant monkeys exposed to house dust mite allergen and ozone

    SciTech Connect

    Joad, Jesse P. Kott, Kayleen S.; Bric, John M.; Schelegle, Edward S.; Gershwin, Laurel J.; Plopper, Charles G.; Peake, Janice L.; Pinkerton, Kent E.

    2008-01-15

    Inhaled corticosteroids (ICS) are recommended to treat infants with asthma, some with intermittent asthma. We previously showed that exposing infant monkeys to allergen/ozone resulted in asthma-like characteristics of their airways. We evaluated the effects of ICS on histology and intrinsic responsiveness of allergen/ozone-exposed and normal infant primate airways. Infant monkeys were exposed by inhalation to (1) filtered air and saline, (2) house dust mite allergen (HDMA) + ozone and saline, (3) filtered air and ICS (budesonide) or (4) HDMA + ozone and ICS. Allergen/ozone exposures started at 1 month and ICS at 3 months of age. At 6 months of age, methacholine-induced changes in luminal area of airways in proximal and distal lung slices were determined using videomicrometry, followed by histology of the same slices. Proximal airway responsiveness was increased by allergen/ozone and by ICS. Eosinophil profiles were increased by allergen/ozone in both proximal and distal airways, an effect that was decreased by ICS in distal airways. In both allergen/ozone- and air-exposed monkeys, ICS increased the number of alveolar attachments in distal airways, decreased mucin in proximal airways and decreased epithelial volume in both airways. ICS increased smooth muscle in air-exposed animals while decreasing it in allergen/ozone-exposed animals in both airways. In proximal airways, there was a small but significant positive correlation between smooth muscle and airway responsiveness, as well as between alveolar attachments and responsiveness. ICS change morphology and function in normal airways as well as allergen/ozone-exposed airways, suggesting that they should be reserved for infants with active symptoms.

  2. N-linked oligosaccharides play a role in disulphide-dependent dimerization of intestinal mucin Muc2.

    PubMed Central

    Bell, Sherilyn L; Xu, Gongqiao; Khatri, Ismat A; Wang, Rongquan; Rahman, Sameera; Forstner, Janet F

    2003-01-01

    Within the C-terminal domain of many secretory mucins is a 'cystine knot' (CK), which is needed for dimer formation in the endoplasmic reticulum. Previous studies indicate that in addition to an unpaired cysteine, the three intramolecular cystine bonds of the knot are important for stability of the dimers formed by rat intestinal mucin Muc2. The present study was undertaken to determine whether the two N-glycans N9 and N10, located near the first and second cysteines of the knot, also play a role in dimer formation. The C-terminal domain of rat Muc2 (RMC), a truncated RMC mutant containing the CK, and mutants lacking N9 and N10 sites, were expressed in COS-1 cells and the products monitored by radioactive [(35)S]Met/Cys metabolic pulse-chase and immunoprecipitation. Mutation of N9, but not N10, caused increased synthesis of dimers over a 2-h chase period. The N9 mutant remained associated with calreticulin for a prolonged period. About 34-38% of the total labelled products of RMC and its mutants was secreted into the media by 2 h, but the proportion in dimer form was dramatically reduced for the N9 mutant, suggesting lower dimer stability relative to RMC or its N10 mutant. We conclude that under normal conditions the presence of the N9 glycan functions to maintain a folding rate for mucin monomers that is sufficiently slow to allow structural maturation and stability of Muc2 dimers. To our knowledge this report is the first demonstration that a specific N-glycan plays a definitive role in mucin dimer formation. PMID:12744721

  3. Systems physiology of the airways in health and obstructive pulmonary disease.

    PubMed

    Bates, Jason H T

    2016-09-01

    Fresh air entering the mouth and nose is brought to the blood-gas barrier in the lungs by a repetitively branching network of airways. Provided the individual airway branches remain patent, this airway tree achieves an enormous amplification in cross-sectional area from the trachea to the terminal bronchioles. Obstructive lung diseases such as asthma occur when airway patency becomes compromised. Understanding the pathophysiology of these obstructive diseases thus begins with a consideration of the factors that determine the caliber of an individual airway, which include the force balance between the inward elastic recoil of the airway wall, the outward tethering forces of its parenchymal attachments, and any additional forces due to contraction of airway smooth muscle. Other factors may also contribute significantly to airway narrowing, such as thickening of the airway wall and accumulation of secretions in the lumen. Airway obstruction becomes particularly severe when these various factors occur in concert. However, the effect of airway abnormalities on lung function cannot be fully understood only in terms of what happens to a single airway because narrowing throughout the airway tree is invariably heterogeneous and interdependent. Obstructive lung pathologies thus manifest as emergent phenomena arising from the way in which the airway tree behaves a system. These emergent phenomena are studied with clinical measurements of lung function made by spirometry and by mechanical impedance measured with the forced oscillation technique. Anatomically based computational models are linking these measurements to underlying anatomic structure in systems physiology terms. WIREs Syst Biol Med 2016, 8:423-437. doi: 10.1002/wsbm.1347 For further resources related to this article, please visit the WIREs website. PMID:27340818

  4. Appendiceal mucinous neoplasms: a clinicopathologic analysis of 107 cases.

    PubMed

    Misdraji, Joseph; Yantiss, Rhonda K; Graeme-Cook, Fiona M; Balis, Ulysses J; Young, Robert H

    2003-08-01

    The classification of appendiceal mucinous tumors is controversial and terminology used for them inconsistent, particularly when they lack overtly malignant features but are associated with extra-appendiceal spread. We reviewed 107 appendiceal mucinous neoplasms and classified them as low-grade appendiceal mucinous neoplasm (LAMN) (n = 88), mucinous adenocarcinomas (MACAs) (n = 16), or discordant (n = 3) based on architectural and cytologic features. LAMNs were characterized by a villous or flat proliferation of mucinous epithelium with low-grade atypia. Thirty-nine tumors were confined to the appendix, but 49 had extra-appendiceal tumor spread, including 39 with peritoneal tumor characterized by mucin pools harboring low-grade mucinous epithelium, usually dissecting in a hyalinized stroma. Eight of the 16 MACAs lacked destructive invasion of the appendiceal wall and eight showed an infiltrative pattern of invasion. Extra-appendiceal tumor spread was present in 12 MACAs (four peritoneum, seven peritoneum and ovaries; one ovaries only). In MACAs with an infiltrative pattern, peritoneal tumor consisted of glands and single cells in a desmoplastic stroma. The peritoneal tumor in the remaining cases consisted of mucin pools that contained mucinous epithelium with high-grade atypia and, in some cases, increased cellularity compared with that seen in peritoneal spread in cases of LAMN. Three cases were classified as discordant because the appendiceal tumors were LAMNs but the peritoneal tumors were high-grade. Follow-up was available for 49 LAMNs, 15 MACAs, and 2 discordant cases. None of the patients with LAMNs confined to the appendix experienced recurrence (median follow-up 6 years). LAMNs with extra-appendiceal spread were associated with 3-, 5-, and 10-year survival rates of 100%, 86%, and 45%, respectively. Patients with MACA had 3- and 5-year survival rates of 90% and 44%, respectively (p = 0.04). The bulk of peritoneal disease correlated with prognosis among

  5. Secret Places.

    ERIC Educational Resources Information Center

    Ridolfi, Kerry

    1997-01-01

    Argues that children are as deep as the ocean, with secret places inside of them waiting to be opened. Notes that it is powerful for students to learn they can make sense of the world through words, and describes inviting them into poetry as they read poetry, create poetry packets, and write and revise poems. (SR)

  6. c-Myc regulates proliferation and Fgf10 expression in airway smooth muscle after airway epithelial injury in mouse.

    PubMed

    Volckaert, Thomas; Campbell, Alice; De Langhe, Stijn

    2013-01-01

    During lung development, Fibroblast growth factor 10 (Fgf10), which is expressed in the distal mesenchyme and regulated by Wnt signaling, acts on the distal epithelial progenitors to maintain them and prevent them from differentiating into proximal (airway) epithelial cells. Fgf10-expressing cells in the distal mesenchyme are progenitors for parabronchial smooth muscle cells (PSMCs). After naphthalene, ozone or bleomycin-induced airway epithelial injury, surviving epithelial cells secrete Wnt7b which then activates the PSMC niche to induce Fgf10 expression. This Fgf10 secreted by the niche then acts on a subset of Clara stem cells to break quiescence, induce proliferation and initiate epithelial repair. Here we show that conditional deletion of the Wnt target gene c-Myc from the lung mesenchyme during development does not affect proper epithelial or mesenchymal differentiation. However, in the adult lung we show that after naphthalene-mediated airway epithelial injury c-Myc is important for the activation of the PSMC niche and as such induces proliferation and Fgf10 expression in PSMCs. Our data indicate that conditional deletion of c-Myc from PSMCs inhibits airway epithelial repair, whereas c-Myc ablation from Clara cells has no effect on airway epithelial regeneration. These findings may have important implications for understanding the misregulation of lung repair in asthma and COPD. PMID:23967208

  7. Stimulation of Mucin, Mucus, and Viscosity during Lubiprostone in Patients with Chronic Constipation may Potentially Lead to Increase of Lubrication

    PubMed Central

    Majewski, Marek; Sarosiek, Irene; Wallner, Grzegorz; Edlavitch, Stanley A; Sarosiek, Jerzy

    2014-01-01

    Objectives: The purpose of this clinical trial was to explore whether lubiprostone increases the rate of mucus and mucin secretion and its viscosity in chronic constipation (CC) patients. The secretion of chloride (CS) into the gastrointestinal tract lumen is pivotal in the body's ability to process non-digestible food components. CS sets the optimal rate of hydration for non-digestible food components, their fluidity, and their adequate propulsion along the alimentary tract. Chloride is also instrumental in the secretion of alimentary tract mucus, and the formation of a gel-like, viscous mucus-buffer layer. This layer acts as the first line and vanguard of the mucosal barrier. This barrier is essential in mucosal lubrication and protection. Lubiprostone, a novel chloride channel stimulator ClC-2, is currently approved for the treatment of CC. Its impact on mucus, mucus secretion, and viscosity is not established. Methods: A double-blind, crossover trial was approved by the IRBs at the Kansas University Medical Center (Kansas City, KS) (study site) and at the Texas Tech University HSC (El Paso, TX) (analysis site). The study included 20 patients (17 females (F); mean age: 37 years) with symptoms of CC diagnosed according to the Rome III criteria. Patients were randomized to 1 week of therapy with lubiprostone or placebo followed by a 1 week washout and 1 week of the alternative therapy. Gastric juice was collected basally and during stimulation with pentagastrin (6 μg/kg body weight subcutaneously) at the end of weeks 1 and 3. Pentagastrin stimulation mimics food stimulation. The mucus content in gastric juice was assessed gravimetrically. The mucin content was measured after its purification using ultracentrifugation. The viscosity of the gastric secretion was measured using a digital viscometer. Results: In comparison with placebo, the volume of gastric secretion in patients with CC during administration of lubiprostone increased significantly by 50% (86.3 vs

  8. Mucin Promotes Rapid Surface Motility in Pseudomonas aeruginosa

    PubMed Central

    Yeung, Amy T. Y.; Parayno, Alicia; Hancock, Robert E. W.

    2012-01-01

    ABSTRACT An important environmental factor that determines the mode of motility adopted by Pseudomonas aeruginosa is the viscosity of the medium, often provided by adjusting agar concentrations in vitro. However, the viscous gel-like property of the mucus layer that overlays epithelial surfaces is largely due to the glycoprotein mucin. P. aeruginosa is known to swim within 0.3% (wt/vol) agar and swarm on the surface at 0.5% (wt/vol) agar with amino acids as a weak nitrogen source. When physiological concentrations or as little as 0.05% (wt/vol) mucin was added to the swimming agar, in addition to swimming, P. aeruginosa was observed to undergo highly accelerated motility on the surface of the agar. The surface motility colonies in the presence of mucin appeared to be circular, with a bright green center surrounded by a thicker white edge. While intact flagella were required for the surface motility in the presence of mucin, type IV pili and rhamnolipid production were not. Replacement of mucin with other wetting agents indicated that the lubricant properties of mucin might contribute to the surface motility. Based on studies with mutants, the quorum-sensing systems (las and rhl) and the orphan autoinducer receptor QscR played important roles in this form of surface motility. Transcriptional analysis of cells taken from the motility zone revealed the upregulation of genes involved in virulence and resistance. Based on these results, we suggest that mucin may be promoting a new or highly modified form of surface motility, which we propose should be termed “surfing.” PMID:22550036

  9. Analysis of Candida albicans adhesion to salivary mucin.

    PubMed Central

    Hoffman, M P; Haidaris, C G

    1993-01-01

    Clearance of Candida albicans from the oral cavity is thought to be mediated via specific receptor-ligand interactions between salivary constituents and the fungus. Since surfaces in the oral cavity are normally coated with a saliva-derived pellicle, specific interactions between salivary constituents and C. albicans may also contribute to adhesion of C. albicans to the oral mucosa and dental prostheses. Therefore, the purpose of this study was to identify salivary constituents to which C. albicans is capable of binding. A solid-phase overlay assay was used in which electrophoretically separated rat and human salivary constituents bound to membrane filters were incubated with radiolabelled C. albicans cells. C. albicans adhered to a single salivary component from each host. Correlation of cell-binding activity with specific monoclonal antibody (MAb)-binding activity indicated that the constituent bound by C. albicans in human saliva was low-molecular-weight mucin (MG2) and that in rat saliva was rat submandibular gland (RSMG) mucin. Further studies showed an identical cell hybridization signal and MAb colocalization by using RSMG ductal saliva and an aqueous RSMG extract in the solid-phase overlay assay. Analysis of cell binding to the aqueous extract of RSMG fractionated by anion-exchange chromatography demonstrated that C. albicans binding was restricted to an acidic subfraction of the RSMG extract, which also bound the RSMG mucin-specific MAb. The Candida-binding fraction contained predominantly RSMG mucin glycoprotein and also a noncovalently associated, chloroform-extractable material. Furthermore, we identified two strains of C. albicans which differed severalfold in the ability to bind RSMG mucin in the overlay assay. These results suggest that C. albicans binds to only a specific subfraction of RSMG mucin and that the two C. albicans strains tested differ in the ability to bind RSMG mucin subfractions. Images PMID:8478083

  10. Relationship between airway ion transport and a mild pulmonary disease mutation in CFTR.

    PubMed

    Walker, L C; Venglarik, C J; Aubin, G; Weatherly, M R; McCarty, N A; Lesnick, B; Ruiz, F; Clancy, J P; Sorscher, E J

    1997-05-01

    Patients with cystic fibrosis (CF) display defects in airway ion transport, but the influence of airway transport phenotype on improved prognosis is not known. We studied airway bioelectric properties in five CF patients with the rare A455E mutation that is associated with mild pulmonary disease. We also evaluated five patients possessing premature truncation mutations (G542X and R553X) for which an association with mild pulmonary disease has not been as well established. We found no evidence in vivo that a mild lung disease mutation in the CF transmembrane regulator gene (CFTR) led to correction or partial correction of: (1) unstimulated Cl- secretion; (2) beta-agonist-activated Cl- secretion; (3) basal sodium reabsorption; or (4) amiloride-sensitive airway sodium transport. Early phase therapeutic trials in CF, including human gene transfer trials, rely heavily on improvements in airway potential difference to identify promising interventions and an improved prognosis. Based on our findings in a naturally occurring group of CF patients with an improved pulmonary prognosis (A455E), one can argue that marked clinical benefit might be possible without any improvement whatsoever in airway bioelectric phenotype. Moreover, if genetic modifiers exist that influence the severity of a particular CFTR mutation (e.g., A455E), these may be independent of human airway Cl-secretion in vivo, since we detected minimal Cl--secretory responses in patients with A455E. PMID:9154877

  11. MicroRNA regulation of airway smooth muscle function.

    PubMed

    Sun, Maoyun; Lu, Quan

    2016-06-01

    Airway smooth muscle (ASM) controls airway narrowing and plays a pivotal role in the pathogenesis of asthma. MicroRNAs are small yet powerful gene tuners that regulate diverse cellular processes. Recent studies have demonstrated the versatile role of microRNAs in regulating multiple ASM phenotypes that are critically involved in asthma pathogenesis. These ASM phenotypes include proliferation, cell size, chemokine secretion, and contractility. Here we review microRNA-mediated regulation of ASM functions and discuss the potential of microRNAs as a novel class of therapeutic targets to improve ASM function for asthma therapy. PMID:26812790

  12. Complete sequence of the human mucin MUC4: a putative cell membrane-associated mucin.

    PubMed Central

    Moniaux, N; Nollet, S; Porchet, N; Degand, P; Laine, A; Aubert, J P

    1999-01-01

    The MUC4 gene, which encodes a human epithelial mucin, is expressed in various epithelial tissues, just as well in adult as in poorly differentiated cells in the embryo and fetus. Its N-terminus and central sequences have previously been reported as comprising a 27-residue peptide signal, followed by a large domain varying in length from 3285 to 7285 amino acid residues. The present study establishes the whole coding sequence of MUC4 in which the C-terminus is 1156 amino acid residues long and shares a high degree of similarity with the rat sialomucin complex (SMC). SMC is a heterodimeric glycoprotein complex composed of mucin (ascites sialoglycoprotein 1, ASGP-1) and transmembrane (ASGP-2) subunits. The same organization is found in MUC4, where the presence of a GlyAspProHis proteolytic site may cleave the large precursor into two subunits, MUC4alpha and MUC4beta. Like ASGP-2, which binds the receptor tyrosine kinase p185(neu), MUC4beta possesses two epidermal growth factor-like domains, a transmembrane sequence and a potential phosphorylated site. MUC4, the human homologue of rat SMC, may be a heterodimeric bifunctional cell-surface glycoprotein of 2.12 micrometers. These results confer a new biological role for MUC4 as a ligand for ErbB2 in cell signalling. PMID:10024507

  13. Role of upper airway ultrasound in airway management.

    PubMed

    Osman, Adi; Sum, Kok Meng

    2016-01-01

    Upper airway ultrasound is a valuable, non-invasive, simple, and portable point of care ultrasound (POCUS) for evaluation of airway management even in anatomy distorted by pathology or trauma. Ultrasound enables us to identify important sonoanatomy of the upper airway such as thyroid cartilage, epiglottis, cricoid cartilage, cricothyroid membrane, tracheal cartilages, and esophagus. Understanding this applied sonoanatomy facilitates clinician to use ultrasound in assessment of airway anatomy for difficult intubation, ETT and LMA placement and depth, assessment of airway size, ultrasound-guided invasive procedures such as percutaneous needle cricothyroidotomy and tracheostomy, prediction of postextubation stridor and left double-lumen bronchial tube size, and detecting upper airway pathologies. Widespread POCUS awareness, better technological advancements, portability, and availability of ultrasound in most critical areas facilitate upper airway ultrasound to become the potential first-line non-invasive airway assessment tool in the future. PMID:27529028

  14. Expression and secretion of Aspergillus fumigatus proteases are regulated in response to different protein substrates

    PubMed Central

    Farnell, Edward; Rousseau, Karine; Thornton, David J.; Bowyer, Paul; Herrick, Sarah E.

    2012-01-01

    The ubiquitous filamentous fungus Aspergillus fumigatus secretes a number of allergens with protease activity and has been linked to a variety of allergic conditions such as Severe Asthma with Fungal Sensitization (SAFS) and Allergic Bronchopulmonary Aspergillosis (ABPA). However, it is unclear which allergen proteases are being secreted during fungal invasion and whether the local biological environment regulates their expression. Understanding the dynamic expression of allergen proteases during growth of A. fumigatus may lead to further characterisation of the pathogenesis of these disorders as well as improved standardisation in the commercial production of these allergens. Secretion of proteases during germination and early growth of A. fumigatus was investigated in response to various complex protein sources (pig lung homogenate, mucin or casein). Protease inhibitor studies demonstrated that A. fumigatus (AF293 strain) secretes predominately serine proteases during growth in pig lung based medium and mainly metalloproteases during growth in casein based medium but suppressed protease secretion in unmodified Vogel's minimal medium and secreted both types in mucin based medium. Analysis of gene transcription and protein identification by mass spectrometry showed that the matrix metalloprotease, Mep/Asp f 5 and the serine protease, Alp1/Asp f 13, were upregulated and secreted during growth in pig lung medium, whereas Alp1 was predominately expressed and secreted in mucin based medium. In casein medium, the matrix metalloprotease, Lap1, was also upregulated and secreted in addition to Mep and Alp1. These findings suggest that A. fumigatus is able to detect different complex proteins available as substrates in its environment and regulate protease secretion accordingly. There is a requirement for the standardisation of A. fumigatus allergen extracts used both in clinical diagnosis of A. fumigatus allergy and in research studies. PMID:22954343

  15. Real-time imaging of exocytotic mucin release and swelling in Calu-3 cells using acridine orange

    PubMed Central

    Shumilov, Dmytro; Popov, Alexander; Fudala, Rafal; Akopova, Irina; Gryczynski, Ignacy; Borejdo, Julian; Gryczynski, Zygmunt; Grygorczyk, Ryszard

    2014-01-01

    Mucus secretion is the first-line of defence against the barrage of irritants inhaled into human lungs, but abnormally thick and viscous mucus results in many respiratory diseases. Understanding the processes underlying mucus pathology is hampered, in part, by lack of appropriate experimental tools for labeling and studying mucin granule secretion from live cells with high sensitivity and temporal resolution. In this report we present original spectroscopic properties of acridine orange (AO) which could be utilized to study granule release and mucin swelling with various advanced fluorescence imaging approaches. Low concentration (<200 μM) AO solutions presented absorption maximum at 494 nm, emission maximum at 525 nm and only ~1.76 ns fluorescence lifetime. By contrast at high concentrations (4–30 mM) favoring formation of AO aggregates, a very different absorption with maximum at ~440 nm, dramatically red-shifted emission with maximum at 630 nm, and over 10-fold increased fluorescence lifetime (~20 ns) was observed. To verify potential utility of AO for real-time imaging we have performed confocal, total internal reflection fluorescence (TIRF) and fluorescence lifetime imaging (FLIM) of AO-stained Calu-3 cells. We found similar red-shifted fluorescence spectra and long fluorescence lifetime in intracellular granules as compared to that in the cytoplasm consistent with granular AO accumulation. Mechanical stimulation of Calu-3 cells resulted in multiple exocytotic secretory events of AO-stained granules followed by post-exocytotic swelling of their fluorescently-labeled content that was seen in single-line TIRF images as rapidly-expanding bright-fluorescence patches. The rate of their size expansion followed first-order kinetics with diffusivity of 3.98 ± 0.07 × 10−7 cm2/s, as expected for mucus gel swelling. This was followed by fluorescence decrease due to diffusional loss of AO that was ~10-fold slower in the secreted mucus compared to bulk aqueous

  16. Real-time imaging of exocytotic mucin release and swelling in Calu-3 cells using acridine orange.

    PubMed

    Shumilov, Dmytro; Popov, Alexander; Fudala, Rafal; Akopova, Irina; Gryczynski, Ignacy; Borejdo, Julian; Gryczynski, Zygmunt; Grygorczyk, Ryszard

    2014-03-15

    Mucus secretion is the first-line of defence against the barrage of irritants inhaled into human lungs, but abnormally thick and viscous mucus results in many respiratory diseases. Understanding the processes underlying mucus pathology is hampered, in part, by lack of appropriate experimental tools for labeling and studying mucin granule secretion from live cells with high sensitivity and temporal resolution. In this report we present original spectroscopic properties of acridine orange (AO) which could be utilized to study granule release and mucin swelling with various advanced fluorescence imaging approaches. Low concentration (<200 μM) AO solutions presented absorption maximum at 494 nm, emission maximum at 525 nm and only ∼1.76 ns fluorescence lifetime. By contrast at high concentrations (4-30 mM) favoring formation of AO aggregates, a very different absorption with maximum at ∼440 nm, dramatically red-shifted emission with maximum at 630 nm, and over 10-fold increased fluorescence lifetime (∼20 ns) was observed. To verify potential utility of AO for real-time imaging we have performed confocal, total internal reflection fluorescence (TIRF) and fluorescence lifetime imaging (FLIM) of AO-stained Calu-3 cells. We found similar red-shifted fluorescence spectra and long fluorescence lifetime in intracellular granules as compared to that in the cytoplasm consistent with granular AO accumulation. Mechanical stimulation of Calu-3 cells resulted in multiple exocytotic secretory events of AO-stained granules followed by post-exocytotic swelling of their fluorescently-labeled content that was seen in single-line TIRF images as rapidly-expanding bright-fluorescence patches. The rate of their size expansion followed first-order kinetics with diffusivity of 3.98±0.07×10(-7)c m(2)/s, as expected for mucus gel swelling. This was followed by fluorescence decrease due to diffusional loss of AO that was ∼10-fold slower in the secreted mucus compared to bulk aqueous

  17. Biomimetic mucin modified PLGA nanoparticles for enhanced blood compatibility.

    PubMed

    Thasneem, Y M; Rekha, M R; Sajeesh, S; Sharma, Chandra P

    2013-11-01

    Efforts to develop long circulating polymeric nanoparticles have propelled many strategies in nanoparticle surface modification to bypass immune surveillance and systemic clearance. In this context, our present study reports on the preparation and evaluation of mucin functionalized poly lactic-co-glycolic acid (PLGA) nanoparticles as hemocompatible, cell penetrating nanoparticulate drug delivery system. Amino groups of mucin were conjugated to the terminal carboxylic acid groups on PLGA to be followed by nanoparticle synthesis via standard solvent evaporation technique. Detailed in vitro experiments were performed to illustrate the significance of alternating copolymer structured mucin modified PLGA nanoparticles in terms of enhanced hemocompatibility and cellular uptake. Mucylation proved promising in controlling PLGA nanoparticle- interaction with plasma proteins (opsonins) and blood components via hemolysis, thrombogenecity and complement activation. Besides hemocompatibility, the modified and unmodified nanoparticles were also found to be cytocompatible with L929 and C6 cell lines. The fluorescent and confocal image analysis evaluated the extent of cellular uptake of nanoparticles into C6 cells. Specifically the combination of stealth properties and cellular internalization capacity of mucin modified PLGA nanoparticle (PLGA-Mucin) lead us to propose it as a safe, efficient and multifunctional nanoplatform for disease specific intravenous drug delivery applications as far as in vitro experiments are concerned. PMID:23978287

  18. Covalently-crosslinked mucin biopolymer hydrogels for sustained drug delivery.

    PubMed

    Duffy, Connor V; David, Laurent; Crouzier, Thomas

    2015-07-01

    The sustained delivery of both hydrophobic and hydrophilic drugs from hydrogels has remained a challenge requiring the design and scalable production of complex multifunctional synthetic polymers. Here, we demonstrate that mucin glycoproteins, the gel-forming constituents of native mucus, are suitable for assembly into robust hydrogels capable of facilitating the sustained release of hydrophobic and hydrophilic drugs. Covalently-crosslinked mucin hydrogels were generated via exposure of methacrylated mucin to ultraviolet light in the presence of a free radical photoinitiator. The hydrogels exhibited an elastic modulus similar to that of soft mammalian tissue and were sensitive to proteolytic degradation by pronase. Paclitaxel, a hydrophobic anti-cancer drug, and polymyxin B, a positively-charged hydrophilic antibacterial drug, were retained in the hydrogels and released linearly with time over seven days. After four weeks of drug release, the hydrogels continued to release sufficient amounts of active paclitaxel to reduce HeLa cell viability and sufficient amounts of active polymyxin B to prevent bacterial proliferation. Along with previously-established anti-inflammatory, anti-viral, and hydrocarbon-solubilizing properties of mucin, the results of this study establish mucin as a readily-available, chemically-versatile, naturally-biocompatible alternative to complex multifunctional synthetic polymers as building blocks in the design of biomaterials for sustained drug delivery. PMID:25818947

  19. CYSTIC FIBROSIS: AN INHERITED DISEASE AFFECTING MUCIN-PRODUCING ORGANS

    PubMed Central

    Ehre, Camille; Ridley, Caroline; Thornton, David J

    2014-01-01

    Our current understanding of cystic fibrosis (CF) has revealed that the biophysical properties of mucus play a considerable role in the pathogenesis of the disease in view of the fact that most mucus-producing organs are affected in CF patients. In this review, we discuss the potential causal relationship between altered cystic fibrosis transmembrane conductance regulator (CFTR) function and the production of mucus with abnormal biophysical properties in the intestine and lungs, highlighting what has been learned from cell cultures and animal models that mimic CF pathogenesis. A similar cascade of events, including mucus obstruction, infection and inflammation, is common to all epithelia affected by impaired surface hydration. Hence, the main structural components of mucus, namely the polymeric, gel-forming mucins, are critical to the onset of the disease. Defective CFTR leads to epithelial surface dehydration, altered pH/electrolyte composition and mucin concentration. Further, it can influence mucin transition from the intracellular to extracellular environment, potentially resulting in aberrant mucus gel formation. While defective HCO3− production has long been identified as a feature of CF, it has only recently been considered as a key player in the transition phase of mucins. We conclude by examining the influence of mucins on the biophysical properties of CF sputum and discuss existing and novel therapies aimed at removing mucus from the lungs. PMID:24685676

  20. Cystic mucinous adenocarcinoma of the lung: a case report

    PubMed Central

    2011-01-01

    Mucinous cystic tumors of the lung are uncommon, the preoperative pathologic diagnosis is difficult and their biological behavior is still controversial. We report the case of a patient with a clinically benign cystic lesion that post-operatively showed to be consistent with an invasive adenocarcinoma arising in a mucinous cystadenoma of the lung, We underline the difficulty of the clinical pre-operative diagnosis of this cystic neoplasia radiologically mimicking a hydatid cyst, and we report the negative TTF1 immunostaining potentially misleading in the differential diagnosis with metastatic mucinous carcinomas. Finallly, we evidence the presence of a pre-existing mucinous benign lesion suggesting early and complete resection of benign appearing lung cysts because they can undergo malignant transformation if left untreated or they can already harbor foci of invasive carcinoma at the time of the presentation. Even if a good prognosis, better than in other lung carcinomas, with no recurrrence or metastasis after complete surgical exicision, has been reported for cystic mucinous cystoadenocarcinomas, the follow-up showed an aggressive biological behaviour, with the early onset of metastasis, in keeping with P53 positive immunostaining and high Ki-67 proliferation index. PMID:21970610

  1. Human milk mucin inhibits rotavirus replication and prevents experimental gastroenteritis.

    PubMed Central

    Yolken, R H; Peterson, J A; Vonderfecht, S L; Fouts, E T; Midthun, K; Newburg, D S

    1992-01-01

    Acute gastrointestinal infections due to rotaviruses and other enteric pathogens are major causes of morbidity and mortality in infants and young children throughout the world. Breast-feeding can reduce the rate of serious gastroenteritis in infants; however, the degrees of protection offered against rotavirus infection vary in different populations. The mechanisms associated with milk-mediated protection against viral gastroenteritis have not been fully elucidated. We have isolated a macromolecular component of human milk that inhibits the replication of rotaviruses in tissue culture and prevents the development of gastroenteritis in an animal model system. Purification of the component indicates that the antiviral activity is associated with an acidic fraction (pI = 4.0-4.6), which is free of detectable immunoglobulins. Furthermore, high levels of antiviral activity are associated with an affinity-purified complex of human milk mucin. Deglycosylation of the mucin complex results in the loss of antiviral activity. Further purification indicated that rotavirus specifically binds to the milk mucin complex as well as to the 46-kD glycoprotein component of the complex. Binding to the 46-kD component was substantially reduced after chemical hydrolysis of sialic acid. We have documented that human milk mucin can bind to rotavirus and inhibit viral replication in vitro and in vivo. Variations in milk mucin glycoproteins may be associated with different levels of protection against infection with gastrointestinal pathogens. Images PMID:1331178

  2. Lawsonia intracellularis infection of intestinal crypt cells is associated with specific depletion of secreted MUC2 in goblet cells

    PubMed Central

    Bengtsson, Rebecca J.; MacIntyre, Neil; Guthrie, Jack; Wilson, Alison D.; Finlayson, Heather; Matika, Oswald; Pong-Wong, Ricardo; Smith, Sionagh H.; Archibald, Alan L.; Ait-Ali, Tahar

    2015-01-01

    The expression patterns of secreted (MUC2 and MUC5AC) and membrane-tethered (MUC1, MUC4, MUC12 and MUC13) mucins were monitored in healthy pigs and pigs challenged orally with Lawsonia intracellularis. These results showed that the regulation of mucin gene expression is distinctive along the GI tract of the healthy pig, and may reflect an association between the function of the mucin subtypes and different physiological demands at various sites. We identified a specific depletion of secreted MUC2 from goblet cells in infected pigs that correlated with the increased level of intracellular bacteria in crypt cells. We concluded that L. intracellularis may influence MUC2 production, thereby altering the mucus barrier and enabling cellular invasion. PMID:26377360

  3. Lawsonia intracellularis infection of intestinal crypt cells is associated with specific depletion of secreted MUC2 in goblet cells.

    PubMed

    Bengtsson, Rebecca J; MacIntyre, Neil; Guthrie, Jack; Wilson, Alison D; Finlayson, Heather; Matika, Oswald; Pong-Wong, Ricardo; Smith, Sionagh H; Archibald, Alan L; Ait-Ali, Tahar

    2015-11-15

    The expression patterns of secreted (MUC2 and MUC5AC) and membrane-tethered (MUC1, MUC4, MUC12 and MUC13) mucins were monitored in healthy pigs and pigs challenged orally with Lawsonia intracellularis. These results showed that the regulation of mucin gene expression is distinctive along the GI tract of the healthy pig, and may reflect an association between the function of the mucin subtypes and different physiological demands at various sites. We identified a specific depletion of secreted MUC2 from goblet cells in infected pigs that correlated with the increased level of intracellular bacteria in crypt cells. We concluded that L. intracellularis may influence MUC2 production, thereby altering the mucus barrier and enabling cellular invasion. PMID:26377360

  4. Supraglottic airway devices.

    PubMed

    Ramachandran, Satya Krishna; Kumar, Anjana M

    2014-06-01

    Supraglottic airway devices (SADs) are used to keep the upper airway open to provide unobstructed ventilation. Early (first-generation) SADs rapidly replaced endotracheal intubation and face masks in > 40% of general anesthesia cases due to their versatility and ease of use. Second-generation devices have further improved efficacy and utility by incorporating design changes. Individual second-generation SADs have allowed more dependable positive-pressure ventilation, are made of disposable materials, have integrated bite blocks, are better able to act as conduits for tracheal tube placement, and have reduced risk of pulmonary aspiration of gastric contents. SADs now provide successful rescue ventilation in > 90% of patients in whom mask ventilation or tracheal intubation is found to be impossible. However, some concerns with these devices remain, including failing to adequately ventilate, causing airway damage, and increasing the likelihood of pulmonary aspiration of gastric contents. Careful patient selection and excellent technical skills are necessary for successful use of these devices. PMID:24891199

  5. Aggregation of mucin by chromium(III) complexes as revealed by electrokinetic and rheological studies: influence on the tryptic and O-glycanase digestion of mucin.

    PubMed

    Shrivastava, H Yamini; Sreeram, K J; Nair, Balachandran Unni

    2004-04-01

    In the present study, the impact of chromium(III) complexes ([Cr(salen)(H2O)2](+) (1), [Cr(en)3]3+ (2) and [Cr(EDTA)(H2O)]- (3)) on the biophysical properties of mucin like specific viscosity, zeta potential and particle size has been investigated. It is evident from the present investigation that the nature of the coordinated ligand has a major role to play in bringing about the changes in the physical characteristics of the glycoprotein. It was observed that (1) and (3) because of their coordinate mode of binding lead to decrease in the specific viscosity of mucin, whereas (2) on the other hand was found to bring about drastic increase in the mucin viscosity due to sol-gel transition in the mucin conformation. Complex (2) was found to gradually lower the zeta potential value of mucin (particle size=51.5 nm) from -24.8 +/- 1.31 mV to -0.58 +/- 0.30 mV, which reveals aggregation (particle size=216 nm) and subsequent sedimentation of mucin with an increase in the average diameter of mucin particles. The binding of (2) to mucin was found to impart resistance to mucin against both tryptic and O-glycanase digestion, suggesting that, the aggregation of mucin causes conformational as well as configurational changes in the glycoprotein; thus perturbing the location of carbohydrate domains. PMID:14769060

  6. Primary testicular mucinous cystadenoma: Case report and literature review.

    PubMed

    de Lima, Mário Maciel; de Lima, Mário Maciel; Granja, Fabiana

    2015-01-01

    Testicular mucinous cystadenomas are rare in urological practice, and their histogenesis, course and management are debated. We report a primary testicular mucinous cystadenoma in a 54-year old male who presented with left testicular swelling and pain. He denied having a history of cryptorchidism, testicular trauma, infections, urinary complaints, or febrile illnesses. He did not have diabetes, but was on treatment for hypertension. The patient underwent a left inguinal radical orchiectomy, and histological examination of the resected tumour confirmed a primary testicular mucinous cystadenoma. The patient had an uneventful recovery, and is being followed up. Conclusively, urologists need to maintain a high index of suspicion of these tumours and their differentiation from metastatic tumours to ensure optimal therapeutic outcomes. PMID:26600891

  7. [A case of mucinous cystic neoplasm of the liver].

    PubMed

    Tatsumi, Ryoji; Amizuka, Hisato; Matsubara, Yu; Yoshizaki, Koji; Sakamoto, Jun; Sato, Ryu; Kimura, Keisuke; Nishimori, Hiroyuki; Ohta, Tomoyuki

    2015-07-01

    We present a case of resected mucinous cystic neoplasm of the liver in a 71-year-old woman admitted to our hospital with epigastric discomfort. Abdominal ultrasonography and computed tomography revealed a multi-locular cystic tumor measuring 35 mm in diameter in segment IV of the liver. Left hepatic lobectomy was performed based on the diagnosis of mucinous cystic neoplasm of the liver; subsequent histology revealed that the tumor was multi-locular, cystic, and lined with a single layer of columnar epithelium with low-grade atypia and was associated with a typical ovarian-like stroma. There was no evidence (imaging or histological) to support communication of the cyst with the intrahepatic bile duct, despite modest bile deposition being observed in the cystic wall. The definitive diagnosis was mucinous cystic neoplasm with low-grade intrahepatic epithelial neoplasia. PMID:26155869

  8. Age-related changes in mucins from human whole saliva.

    PubMed

    Denny, P C; Denny, P A; Klauser, D K; Hong, S H; Navazesh, M; Tabak, L A

    1991-10-01

    The predominant mucins in human whole saliva, MG1 and MG2, serve to protect and to lubricate the oral cavity. In this study, both unstimulated and stimulated whole salivas were collected from two groups of subjects: young (18-35 years of age) and aged (65-83 years of age). The subjects were in apparent good health. Saliva samples from each subject were analyzed by SDS-PAGE. The gels were stained with Stains-all, and both MG1 and MG2 were quantitated by video-image densitometry. The protocol gave reproducible values for each mucin. The stimulated and unstimulated salivas from aged subjects showed significant reductions in concentrations of both MG1 and MG2, as quantitated in mucin dye-binding units. Possible associations of these reductions with the aging process are discussed. PMID:1719051

  9. Mucin biopolymers as broad-spectrum antiviral agents

    PubMed Central

    Lieleg, Oliver; Lieleg, Corinna; Bloom, Jesse; Buck, Christopher B.; Ribbeck, Katharina

    2012-01-01

    Mucus is a porous biopolymer matrix that coats all wet epithelia in the human body and serves as the first line of defense against many pathogenic bacteria and viruses. However, under certain conditions viruses are able to penetrate this infection barrier, which compromises the protective function of native mucus. Here, we find that isolated porcine gastric mucin polymers, key structural components of native mucus, can protect an underlying cell layer from infection by small viruses such as human papillomavirus (HPV), Merkel cell polyomavirus (MCV), or a strain of influenza A virus. Single particle analysis of virus mobility inside the mucin barrier reveals that this shielding effect is in part based on a retardation of virus diffusion inside the biopolymer matrix. Our findings suggest that purified mucins may be used as a broad-range antiviral supplement to personal hygiene products, baby formula or lubricants to support our immune system. PMID:22475261

  10. Genome wide analysis of the bovine mucin genes and their gastrointestinal transcription profile

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Mucins are large glycoproteins implicated in protection of all mucosal surfaces. In humans and rodents, the mucin gene family has been well described and previous studies have investigated the distribution and function of mucins in the respiratory, urogenital and gastrointestinal (GI) tracts. In con...

  11. GABA selectively increases mucin-1 expression in isolated pig jejunum.

    PubMed

    Braun, Hannah-Sophie; Sponder, Gerhard; Pieper, Robert; Aschenbach, Jörg R; Deiner, Carolin

    2015-11-01

    The inhibitory neurotransmitter GABA (γ-aminobutyric acid) is synthesized by glutamic acid decarboxylase, which is expressed in the central nervous system and in various other tissues including the intestine. Moreover, GABA can be ingested in vegetarian diets or produced by bacterial commensals in the gastrointestinal tract. As previous studies in lung have suggested a link between locally increased GABA availability and mucin 5AC production, the present study sought to test whether the presence or lack of GABA (and its precursor glutamine) has an effect on intestinal mucin expression. Porcine jejunum epithelial preparations were incubated with two different amounts of GABA or glutamine on the mucosal side for 4 h, and changes in the relative gene expression of seven different mucins, enzymes involved in mucin shedding, GABA B receptor, enzymes involved in glutamine/GABA metabolism, glutathione peroxidase 2, and interleukin 10 were examined by quantitative PCR (TaqMan(®) assays). Protein expression of mucin-1 (MUC1) was analyzed by Western blot. On the RNA level, only MUC1 was significantly up-regulated by both GABA concentrations compared with the control. Glutamine-treated groups showed the same trend. On the protein level, all treatment groups showed a significantly higher MUC1 expression than the control group. We conclude that GABA selectively increases the expression of MUC1, a cell surface mucin that prevents the adhesion of microorganisms, because of its size and negative charge, and therefore propose that the well-described positive effects of glutamine on enterocytes and intestinal integrity are partly attributable to effects of its metabolite GABA. PMID:26471792

  12. Clinical benefits of visualization of airway anatomy and manipulation of the endotracheal tube cuff with the GlideScope in the morbidly obese patient during tracheotomy.

    PubMed

    Hartman, Michael T; Lang, John

    2009-12-01

    Inadvertent deflation of the endotracheal tube cuff during a tracheotomy can complicate the surgical procedure, especially in a morbidly obese patient. Also, the anesthesia provider may lose control of the airway, with the inability to reintubate in case of airway edema, airway secretions, or airway fire. The use of the GlideScope video laryngoscope (Verathon Inc, Bothell, Washington) in the morbidly obese patient undergoing a tracheotomy has clinical benefits. This device allowed the visualization of the airway anatomy in 2 patients and the manipulation of the punctured endotracheal tube cuff in one case. PMID:20108730

  13. Issues of critical airway management (Which anesthesia; which surgical airway?).

    PubMed

    Bonanno, Fabrizio Giuseppe

    2012-10-01

    Which anesthesia for patients with critical airway? Safe and effective analgesia and anesthesia in critical airway is a skilled task especially after severe maxillofacial injury combined with head injury and hemorrhagic shock. If on one side sedation is wanted, on the other hand it may worsen the airway and hemodynamic situation to a point where hypoventilation and decrease of blood pressure, common side-effect of many opioids, may prejudice the patient's level of consciousness and hemodynamic compensation, compounding an already critical situation. What to do when endotracheal intubation fails and blood is trickling down the airways in an unconscious patient or when a conscious patient has to sit up to breathe? Which surgical airway in critical airway? Comparative studies among the various methods of emergency surgical airway would be unethical; furthermore, operator's training and experience is relevant for indications and performance. PMID:23248494

  14. Mucinous Borderline Ovarian Tumor in Very Old Aged Postmenopausal Woman

    PubMed Central

    Lee, Seung-Hee; Lee, Hae-Hyeog; Lee, Arum; Kim, Yeon-Suk; Jeon, Dong-Su; Kwak, Jeong Ja; Yang, Yo-Sep

    2015-01-01

    Mucinous borderline ovarian tumors (BOTs) occur most often in women between the ages of 20 and 30. Early-stage detection of the condition has a more favorable prognosis. In this case report, the authors present an elderly 93-year old woman who visited our hospital due to severe abdominal pain after being diagnosed with a pelvic mass 2 years ago and not undergoing any treatment since the diagnosis was made. She underwent emergency left salpingo-oophorectomy and was diagnosed with mucinous BOT according to biopsy results. PMID:26793682

  15. The mucus and mucins of the goblet cells and enterocytes provide the first defense line of the gastrointestinal tract and interact with the immune system

    PubMed Central

    Pelaseyed, Thaher; Bergström, Joakim H.; Gustafsson, Jenny K.; Ermund, Anna; Birchenough, George M. H.; Schütte, André; van der Post, Sjoerd; Svensson, Frida; Rodríguez-Piñeiro, Ana M.; Nyström, Elisabeth E.L.; Wising, Catharina; Johansson, Malin E.V.; Hansson, Gunnar C.

    2014-01-01

    Summary The gastrointestinal tract is covered by mucus that has different properties in the stomach, small intestine and colon. The large highly glycosylated gel-forming mucins MUC2 and MUC5AC are the major components of the mucus in the intestine and stomach, respectively. In the small intestine mucus limits the number of bacteria that can reach the epithelium and the Peyer’s patches. In the large intestine the inner mucus layer separates the commensal bacteria from the host epithelium. The outer colonic mucus layer is the natural habitat for the commensal bacteria. The intestinal goblet cells not only secrete the MUC2 mucin, but also a number of typical mucus components: CLCA1, FCGBP, AGR2, ZG16, and TFF3. The goblet cells have recently been shown to have a novel gate-keeping role for the presentation of oral antigens to the immune system. Goblet cells deliver small intestinal luminal material to the lamina propria dendritic cells of the tolerogenic CD103+-type. In addition to the gel forming mucins, the transmembrane mucins MUC3, MUC12 and MUC17 form the enterocyte glycocalyx that can reach about a micrometer out from the brush border. The MUC17 mucin can shuttle from a surface to an intracellular vesicle localization suggesting that enterocytes might control and report epithelial microbial challenge. There is not only communication from the epithelial cells to the immune system, but also in the opposite direction. One example of this is IL10 that can affect and improve the properties of the inner colonic mucus layer. The mucus and epithelial cells of the gastrointestinal tract are the primary gate keepers and controllers of bacterial interactions with the host immune system, but our understanding of this relationship is still in its infancy. PMID:24942678

  16. The Role of CLCA Proteins in Inflammatory Airway Disease

    PubMed Central

    Patel, Anand C.; Brett, Tom J.; Holtzman, Michael J.

    2014-01-01

    Inflammatory airway diseases such as asthma and chronic obstructive pulmonary disease (COPD) exhibit stereotyped traits that are variably expressed in each person. In experimental mouse models of chronic lung disease, these individual disease traits can be genetically segregated and thereby linked to distinct determinants. Functional genomic analysis indicates that at least one of these traits, mucous cell metaplasia, depends on members of the calcium-activated chloride channel (CLCA) gene family. Here we review advances in the biochemistry of the CLCA family and the evidence of a role for CLCA family members in the development of mucous cell metaplasia and possibly airway hyperreactivity in experimental models and in humans. Based on this information, we develop the model that CLCA proteins are not integral membrane proteins with ion channel function, but instead are secreted signaling molecules that specifically regulate airway target cells in healthy and disease conditions. PMID:18954282

  17. High-frequency oscillation of the airway and chest wall.

    PubMed

    Fink, James B; Mahlmeister, Michael J

    2002-07-01

    High-frequency oscillation (HFO), applied to either the airway or chest wall, has been associated with changes in sputum attributes and clearance. The evolution of evidence, both in vitro and in vivo, supporting the use of HFO is reviewed. Devices that apply HFO to the airway range from the relatively simple mechanical Flutter and Acapella devices to the more complex Percussionaire Intrapercussive Ventilators. and the Hayek Oscillator are designed to provide high-frequency chest wall compression. Operation and use of these devices are described with examples of differentiation of device types by characterization of flows, and airway and esophageal pressures. Although HFO devices span a broad range of costs, they provide a reasonable therapeutic option to support secretion clearance for patients with cystic fibrosis. PMID:12088550

  18. Role of Insulin-like Growth Factor Binding Protein-3 in Allergic Airway Remodeling

    PubMed Central

    Veraldi, Kristen L.; Gibson, Bethany T.; Yasuoka, Hidekata; Myerburg, Michael M.; Kelly, Elizabeth A.; Balzar, Silvana; Jarjour, Nizar N.; Pilewski, Joseph M.; Wenzel, Sally E.; Feghali-Bostwick, Carol A.

    2009-01-01

    Rationale: The hallmarks of allergic asthma are airway inflammation, obstruction, and remodeling. Airway remodeling may lead to irreversible airflow obstruction with increased morbidity and mortality. Despite advances in the treatment of asthma, the mechanisms underlying airway remodeling are still poorly understood. We reported that insulin-like growth factor (IGF) binding proteins (IGFBPs) contribute to extracellular matrix deposition in idiopathic pulmonary fibrosis; however, their contribution to airway remodeling in asthma has not been established. Objectives: We hypothesized that IGFBP-3 is overexpressed in asthma and contributes to airway remodeling. Methods: We evaluated levels of IGFBP-3 in tissues and bronchoalveolar lavage fluid from patients with asthma at baseline and 48 hours after allergen challenge, in reparative epithelium in an in vitro wounding assay, and in conditioned media from cytokine- and growth factor–stimulated primary epithelial cells. Measurements and Main Results: IGFBP-3 levels and distribution were evaluated by Western blot, ELISA, and immunofluorescence. IGFBP-3 is increased in vivo in the airway epithelium of patients with asthma compared with normal control subjects. The concentration of IGFBP-3 is increased in the bronchoalveolar lavage fluid of patients with asthma after allergen challenge, its levels are increased in reparative epithelium in an in vitro wounding assay and in the conditioned medium of primary airway epithelial cell cultures stimulated with IGF-I. Conclusions: Our results suggest that one mechanism of allergic airway remodeling is through the secretion of the profibrotic IGFBP-3 from IGF-I–stimulated airway epithelial cells during allergic inflammation. PMID:19608721

  19. Total airway reconstruction.

    PubMed

    Connor, Matthew P; Barrera, Jose E; Eller, Robert; McCusker, Scott; O'Connor, Peter

    2013-02-01

    We present a case of obstructive sleep apnea (OSA) that required multilevel surgical correction of the airway and literature review and discuss the role supraglottic laryngeal collapse can have in OSA. A 34-year-old man presented to a tertiary otolaryngology clinic for treatment of OSA. He previously had nasal and palate surgeries and a Repose tongue suspension. His residual apnea hypopnea index (AHI) was 67. He had a dysphonia associated with a true vocal cord paralysis following resection of a benign neck mass in childhood. He also complained of inspiratory stridor with exercise and intolerance to continuous positive airway pressure. Physical examination revealed craniofacial hypoplasia, full base of tongue, and residual nasal airway obstruction. On laryngoscopy, the paretic aryepiglottic fold arytenoid complex prolapsed into the laryngeal inlet with each breath. This was more pronounced with greater respiratory effort. Surgical correction required a series of operations including awake tracheostomy, supraglottoplasty, midline glossectomy, genial tubercle advancement, maxillomandibular advancement, and reconstructive rhinoplasty. His final AHI was 1.9. Our patient's supraglottic laryngeal collapse constituted an area of obstruction not typically evaluated in OSA surgery. In conjunction with treating nasal, palatal, and hypopharyngeal subsites, our patient's supraglottoplasty represented a key component of his success. This case illustrates the need to evaluate the entire upper airway in a complicated case of OSA. PMID:22965285

  20. Epithelial hyperplasia, airways

    Cancer.gov

    Number of respiratory epithelial cells is increased diffusely or focally. Frequently luminal protrusions are observed, sometimes forming papillae. Mucous (goblet) cell metaplastic hyperplasia is a variant, in which the respiratory epithelium of conducting airways is replaced by mucous cells either as a single or a pseudostratified layer.

  1. Frequent KRAS mutation in complex mucinous epithelial lesions of the endometrium.

    PubMed

    Alomari, Ahmed; Abi-Raad, Rita; Buza, Natalia; Hui, Pei

    2014-05-01

    KRAS mutation correlates with mucinous differentiation in various human cancers, and recently, was found in a high proportion of a small cohort of papillary mucinous lesions of the endometrium. In this study, a large number of endometrial mucinous lesions were analyzed for the presence of KRAS mutation along with clinical progression. A total of 45 endometrial biopsy/curettage cases were included in the study and classified into the following categories: simple mucinous change (5 cases), complex mucinous change (33 cases) and mucinous adenocarcinoma (7 cases). Follow-up hysterectomy specimens were available in 14 of 33 patients (42%) with complex mucinous lesions, of which 9 cases (64%) showed atypical complex hyperplasia with an average interval of 21 weeks. None of the 5 cases of simple mucinous change showed KRAS mutation. KRAS mutation was observed in 18 of 33 patients with complex mucinous lesions (55%) and in 6 of 7 cases of mucinous adenocarcinoma (86%). Overall, KRAS mutation has a positive predictive value (PPV) of 88% (7/8 cases) for complex atypical hyperplasia or adenocarcinoma in the follow-up hysterectomy. In conclusion, the current data further emphasizes the architectural complexity as an important prognostic indicator for patients with mucinous endometrial lesions. The presence of KRAS mutation in both mucinous adenocarcinoma and complex mucinous changes indicates that KRAS mutational activation is implicated in the pathogenesis of a significant subset of endometrial mucinous carcinoma. With a high PPV, KRAS mutation analysis may offer an additional discriminatory power to refine risk stratification algorithm for patients with endometrial mucinous lesions. PMID:24186144

  2. Mechanisms of airway responses to esophageal acidification in cats.

    PubMed

    Lang, Ivan M; Haworth, Steven T; Medda, Bidyut K; Forster, Hubert; Shaker, Reza

    2016-04-01

    Acid in the esophagus causes airway constriction, tracheobronchial mucous secretion, and a decrease in tracheal mucociliary transport rate. This study was designed to investigate the neuropharmacological mechanisms controlling these responses. In chloralose-anesthetized cats (n = 72), we investigated the effects of vagotomy or atropine (100 μg·kg(-1)·30 min(-1) iv) on airway responses to esophageal infusion of 0.1 M PBS or 0.1 N HCl at 1 ml/min. We quantified 1) diameter of the bronchi, 2) tracheobronchial mucociliary transport rate, 3) tracheobronchial mucous secretion, and 4) mucous content of the tracheal epithelium and submucosa. We found that vagotomy or atropine blocked the airway constriction response but only atropine blocked the increase in mucous output and decrease in mucociliary transport rate caused by esophageal acidification. The mucous cells of the mucosa produced more Alcian blue- than periodic acid-Schiff (PAS)-stained mucosubstances, and the mucous cells of the submucosa produced more PAS- than Alcian blue-stained mucosubstances. Selective perfusion of the different segments of esophagus with HCl or PBS resulted in significantly greater production of PAS-stained mucus in the submucosa of the trachea adjacent to the HCl-perfused esophagus than in that adjacent to the PBS-perfused esophagus. In conclusion, airway constriction caused by esophageal acidification is mediated by a vagal cholinergic pathway, and the tracheobronchial transport response is mediated by cholinergic receptors. Acid perfusion of the esophagus selectively increases production of neutral mucosubstances of the apocrine glands by a local mechanism. We hypothesize that the airway responses to esophageal acid exposure are part of the innate, rather than acute emergency, airway defense system. PMID:26846551

  3. Advances in prehospital airway management

    PubMed Central

    Jacobs, PE; Grabinsky, A

    2014-01-01

    Prehospital airway management is a key component of emergency responders and remains an important task of Emergency Medical Service (EMS) systems worldwide. The most advanced airway management techniques involving placement of oropharyngeal airways such as the Laryngeal Mask Airway or endotracheal tube. Endotracheal tube placement success is a common measure of out-of-hospital airway management quality. Regional variation in regard to training, education, and procedural exposure may be the major contributor to the findings in success and patient outcome. In studies demonstrating poor outcomes related to prehospital-attempted endotracheal intubation (ETI), both training and skill level of the provider are usually often low. Research supports a relationship between the number of intubation experiences and ETI success. National standards for certification of emergency medicine provider are in general too low to guarantee good success rate in emergency airway management by paramedics and physicians. Some paramedic training programs require more intense airway training above the national standard and some EMS systems in Europe staff their system with anesthesia providers instead. ETI remains the cornerstone of definitive prehospital airway management, However, ETI is not without risk and outcomes data remains controversial. Many systems may benefit from more input and guidance by the anesthesia department, which have higher volumes of airway management procedures and extensive training and experience not just with training of airway management but also with different airway management techniques and adjuncts. PMID:24741499

  4. Methods of airway resistance assessment.

    PubMed

    Urbankowski, Tomasz; Przybyłowski, Tadeusz

    2016-01-01

    Airway resistance is the ratio of driving pressure to the rate of the airflow in the airways. The most frequent methods used to measure airway resistance are whole-body plethysmography, the interrupter technique and the forced oscillation technique. All these methods allow to measure resistance during respiration at the level close to tidal volume, they do not require forced breathing manoeuvres or deep breathing during measurement. The most popular method for measuring airway resistance is whole-body plethysmography. The results of plethysmography include among others the following parameters: airway resistance (Raw), airway conductance (Gaw), specific airway resistance (sRaw) and specific airway conductance (sGaw). The interrupter technique is based on the assumption that at the moment of airway occlusion, air pressure in the mouth is equal to the alveolar pressure . In the forced oscillation technique (FOT), airway resistance is calculated basing on the changes in pressure and flow caused by air vibration. The methods for measurement of airway resistance that are described in the present paper seem to be a useful alternative to the most common lung function test - spirometry. The target group in which these methods may be widely used are particularly the patients who are unable to perform spirometry. PMID:27238174

  5. Role of neutrophilic inflammation in ozone-induced epithelial alterations in the nasal airways of rats

    NASA Astrophysics Data System (ADS)

    Cho, Hye Youn

    Ozone is a principal oxidant air pollutant in photochemical smog. Epithelial cells lining the centriacinar region of lung and the proximal aspects of nasal passage are primary target sites for ozone-induced injury in laboratory animals. Acute exposure of rats to high ambient concentrations of ozone (e.g., 0.5 ppm) results in neutrophilic inflammation, epithelial hyperplasia and mucous cell metaplasia (MCM) in the nasal transitional epithelium (NTE) lining the proximal nasal airways. The principal purpose of the present study was to investigate the role of pre-metaplastic cellular responses, especially neutrophilic inflammation, in the pathogenesis of ozone-induced MCM in rat NTE. For this purpose, three specific hypotheses-based whole-animal inhalation studies were conducted. Male F344/N rats were exposed in whole-body inhalation chambers to 0 (filtered air) or 0.5 ppm ozone for 1-3 days (8 h/day). Histochemical, immunochemical, molecular and morphometric techniques were used to investigate the ozone-induced cellular and molecular events in the NTE. Two in vitro studies were also conducted to examine the effects of ozone-inducible cytokines (i.e., tumor necrosis factor-alpha; TNF- a, and interleukin-6; IL-6) on mucin gene (rMuc-5AC) expression. Ozone induced a rapid increase of rMuc-5AC mRNA in nasal tissues within hours after the start of exposure. It preceded the appearance of MCM, and persisted with MCM. Ozone-induced neutrophilic inflammation accompanied the mucin gene upregulation, but was resolved when MCM first appeared in the NTE. Antibody-mediated depletion of circulating neutrophils attenuated ozone-induced MCM, although it did not affect the ozone-induced epithelial hyperplasia and mucin mRNA upregulation. In another study, it was found that preexisting neutrophilic rhinitis induced by endotoxin augmented the ozone-induced MCM. However, pre-existing rhinitis did not alter the severity of ozone-induced epithelial hyperplasia and mucin gene upregulation

  6. Supraglottic airway devices in children

    PubMed Central

    Ramesh, S; Jayanthi, R

    2011-01-01

    Modern anaesthesia practice in children was made possible by the invention of the endotracheal tube (ET), which made lengthy and complex surgical procedures feasible without the disastrous complications of airway obstruction, aspiration of gastric contents or asphyxia. For decades, endotracheal intubation or bag-and-mask ventilation were the mainstays of airway management. In 1983, this changed with the invention of the laryngeal mask airway (LMA), the first supraglottic airway device that blended features of the facemask with those of the ET, providing ease of placement and hands-free maintenance along with a relatively secure airway. The invention and development of the LMA by Dr. Archie Brain has had a significant impact on the practice of anaesthesia, management of the difficult airway and cardiopulmonary resuscitation in children and neonates. This review article will be a brief about the clinical applications of supraglottic airways in children. PMID:22174464

  7. α-N-acetylgalactosaminidase from infant-associated bifidobacteria belonging to novel glycoside hydrolase family 129 is implicated in alternative mucin degradation pathway.

    PubMed

    Kiyohara, Masashi; Nakatomi, Takashi; Kurihara, Shin; Fushinobu, Shinya; Suzuki, Hideyuki; Tanaka, Tomonari; Shoda, Shin-Ichiro; Kitaoka, Motomitsu; Katayama, Takane; Yamamoto, Kenji; Ashida, Hisashi

    2012-01-01

    Bifidobacteria inhabit the lower intestine of mammals including humans where the mucin gel layer forms a space for commensal bacteria. We previously identified that infant-associated bifidobacteria possess an extracellular membrane-bound endo-α-N-acetylgalactosaminidase (EngBF) that may be involved in degradation and assimilation of mucin-type oligosaccharides. However, EngBF is highly specific for core-1-type O-glycan (Galβ1-3GalNAcα1-Ser/Thr), also called T antigen, which is mainly attached onto gastroduodenal mucins. By contrast, core-3-type O-glycans (GlcNAcβ1-3GalNAcα1-Ser/Thr) are predominantly found on the mucins in the intestines. Here, we identified a novel α-N-acetylgalactosaminidase (NagBb) from Bifidobacterium bifidum JCM 1254 that hydrolyzes the Tn antigen (GalNAcα1-Ser/Thr). Sialyl and galactosyl core-3 (Galβ1-3/4GlcNAcβ1-3(Neu5Acα2-6)GalNAcα1-Ser/Thr), a major tetrasaccharide structure on MUC2 mucin primarily secreted from goblet cells in human sigmoid colon, can be serially hydrolyzed into Tn antigen by previously identified bifidobacterial extracellular glycosidases such as α-sialidase (SiaBb2), lacto-N-biosidase (LnbB), β-galactosidase (BbgIII), and β-N-acetylhexosaminidases (BbhI and BbhII). Because NagBb is an intracellular enzyme without an N-terminal secretion signal sequence, it is likely involved in intracellular degradation and assimilation of Tn antigen-containing polypeptides, which might be incorporated through unknown transporters. Thus, bifidobacteria possess two distinct pathways for assimilation of O-glycans on gastroduodenal and intestinal mucins. NagBb homologs are conserved in infant-associated bifidobacteria, suggesting a significant role for their adaptation within the infant gut, and they were found to form a new glycoside hydrolase family 129. PMID:22090027

  8. Microbial-induced meprin β cleavage in MUC2 mucin and a functional CFTR channel are required to release anchored small intestinal mucus

    PubMed Central

    Schütte, André; Ermund, Anna; Becker-Pauly, Christoph; Johansson, Malin E. V.; Rodriguez-Pineiro, Ana M.; Bäckhed, Fredrik; Müller, Stefan; Lottaz, Daniel; Bond, Judith S.; Hansson, Gunnar C.

    2014-01-01

    The mucus that covers and protects the epithelium of the intestine is built around its major structural component, the gel-forming MUC2 mucin. The gel-forming mucins have traditionally been assumed to be secreted as nonattached. The colon has a two-layered mucus system where the inner mucus is attached to the epithelium, whereas the small intestine normally has a nonattached mucus. However, the mucus of the small intestine of meprin β-deficient mice was now found to be attached. Meprin β is an endogenous zinc-dependent metalloprotease now shown to cleave the N-terminal region of the MUC2 mucin at two specific sites. When recombinant meprin β was added to the attached mucus of meprin β-deficient mice, the mucus was detached from the epithelium. Similar to meprin β-deficient mice, germ-free mice have attached mucus as they did not shed the membrane-anchored meprin β into the luminal mucus. The ileal mucus of cystic fibrosis (CF) mice with a nonfunctional cystic fibrosis transmembrane conductance regulator (CFTR) channel was recently shown to be attached to the epithelium. Addition of recombinant meprin β to CF mucus did not release the mucus, but further addition of bicarbonate rendered the CF mucus normal, suggesting that MUC2 unfolding exposed the meprin β cleavage sites. Mucus is thus secreted attached to the goblet cells and requires an enzyme, meprin β in the small intestine, to be detached and released into the intestinal lumen. This process regulates mucus properties, can be triggered by bacterial contact, and is nonfunctional in CF due to poor mucin unfolding. PMID:25114233

  9. A modified Guedel airway for continuous oxygenation and suctioning during fibreoptic bronchoscopy.

    PubMed

    Ayoub, C; Itani, M M; Lteif, A; Baraka, A

    2000-05-01

    We describe a modification to the Guedel airway that improves suction and oxygenation during fibreoptic bronchoscopy. The entire roof of a Guedel airway was removed. Two 2.5-mm internal diameter tracheal tubes were inserted into the modified airway to allow continuous oxygen delivery and suction throughout fibreoptic bronchoscopy. It was tested as a single-use device in ten patients undergoing awake fibreoptic bronchoscopy under sedation and topical anasthesia. During the procedure there were no problems with either fogging of the lens or secretions in the pharynx. In addition, oxyhaemoglobin saturation, as monitored continuously by pulse oximetry, was >/= 97% in all patients. PMID:10792137

  10. Novel Roles for Chloride Channels, Exchangers, and Regulators in Chronic Inflammatory Airway Diseases

    PubMed Central

    Sala-Rabanal, Monica; Yurtsever, Zeynep; Berry, Kayla N.; Brett, Tom J.

    2015-01-01

    Chloride transport proteins play critical roles in inflammatory airway diseases, contributing to the detrimental aspects of mucus overproduction, mucus secretion, and airway constriction. However, they also play crucial roles in contributing to the innate immune properties of mucus and mucociliary clearance. In this review, we focus on the emerging novel roles for a chloride channel regulator (CLCA1), a calcium-activated chloride channel (TMEM16A), and two chloride exchangers (SLC26A4/pendrin and SLC26A9) in chronic inflammatory airway diseases. PMID:26612971

  11. Colonic mucin synthesis is increased by sodium butyrate.

    PubMed

    Finnie, I A; Dwarakanath, A D; Taylor, B A; Rhodes, J M

    1995-01-01

    The effects of sodium butyrate and sodium bromo-octanoate (an inhibitor of beta oxidation) on colonic mucus glycoprotein (mucin) synthesis have been assessed using tissue from colonic resection samples. Epithelial biopsy specimens were incubated for 16 hours in RPMI 1640 with glutamine, supplemented with 10% fetal calf serum and N-acetyl-[3H]-glucosamine ([3H]-Glc NAc), and differing concentrations of sodium butyrate. Incorporation of [3H] Glc NAc into mucin by normal epithelium at least 10 cm distant from colonic cancer was increased in the presence of sodium butyrate in a dose dependent manner, with maximum effect (476%) at a concentration of 0.1 mM (number of specimens = 24 from six patients, p < 0.001). The increase in response to butyrate was not seen when specimens were incubated in the presence of the beta oxidation inhibitor sodium bromo-octanoate 0.05 M. The striking increase in mucin synthesis that results when butyrate is added to standard nutrient medium suggests that this may be an important mechanism affecting the rate of mucin synthesis in vivo and may also explain the therapeutic effect of butyrate in colitis. PMID:7890244

  12. Mupirocin-mucin agar for selective enumeration of Bifidobacterium bifidum.

    PubMed

    Pechar, Radko; Rada, Vojtech; Parafati, Lucia; Musilova, Sarka; Bunesova, Vera; Vlkova, Eva; Killer, Jiri; Mrazek, Jakub; Kmet, Vladimir; Svejstil, Roman

    2014-11-17

    Bifidobacterium bifidum is a bacterial species exclusively found in the human intestinal tract. This species is becoming increasingly popular as a probiotic organism added to lyophilized products. In this study, porcine mucin was used as the sole carbon source for the selective enumeration of B. bifidum in probiotic food additives. Thirty-six bifidobacterial strains were cultivated in broth with mucin. Only 13 strains of B. bifidum utilized the mucin to produce acids. B. bifidum was selectively enumerated in eight probiotic food supplements using agar (MM agar) containing mupirocin (100 mg/L) and mucin (20 g/L) as the sole carbon source. MM agar was fully selective if the B. bifidum species was presented together with Bifidobacterium animalis subsp. lactis, Bifidobacterium breve, and Bifidobacterium longum subsp. longum species and with lactic acid bacteria (lactobacilli, streptococci). Isolated strains of B. bifidum were identified using biochemical, PCR, MALDI-TOF procedures and 16S rRNA gene sequencing. The novel selective medium was also suitable for the isolation of B. bifidum strains from human fecal samples. PMID:25217723

  13. Mucins and Cytokeratins as Serum Tumor Markers in Breast Cancer.

    PubMed

    Nicolini, Andrea; Ferrari, Paola; Rossi, Giuseppe

    2015-01-01

    Structural and functional characteristics of mucins and cytokeratins are shortly described. Thereafter, those commonly used in breast cancer as serum tumor markers are considered. First CA15.3, MCA, CA549, CA27.29 mucins and CYFRA21.1, TPA, TPS cytokeratins alone or in association have been examined in different stages and conditions. Then their usefulness in monitoring disease-free breast cancer patients is evaluated. The central role of the established cut-off and critical change, the "early" treatment of recurrent disease and the potential benefit in survival are other issues that have been highlighted and discussed. The successive sections and subsections deal with the monitoring of advanced disease. In them, the current recommendations and the principal findings on using the above mentioned mucins and cytokeratins have been reported. A computer program for interpreting consecutive measurements of serum tumor markers also has been illustrated. The final part of the chapter is devoted to mucins and cytokeratins as markers of circulating and disseminated tumor cells and their usefulness for prognosis. PMID:26530368

  14. Physical Properties of Human Whole Salivary Mucin:A Dynamic Light Scattering Study

    NASA Astrophysics Data System (ADS)

    Mahajan, Manish; Kumar, Vijay; Saraswat, Mayank; Yadav, Savita; Shukla, N. K.; Singh, T. P.

    2008-04-01

    Human salivary mucin, a primary mucous membrane coating glycoprotein forms the first line of defense against adverse environments, attributed to the complex formation between mucin subunits and non mucin species. Aim of the study was to emphasize the effect of pH, denaturants (guanidinum hydrochloride, urea) and detergents (CHAPS, TRITON X -100, SDS on human whole salivary mucin. Hydrodynamic size distribution was measured using DLS. It was observed that aggregation was due to increase in hydrophobic interactions, believed to be accomplished by unfolding of the protein core. Whereas, the detergents which solubilize the proteins by decreasing hydrophobicity lead to disaggregation of mucin into smaller fragments. Mucin subjected to tobacco extract and upon subsequent addition of nicotine was found to have a disaggregating effect on it, suggesting nicotine may be one of the factors responsible for the disaggregating effect of tobacco on mucin, an important carcinogenetic mechanism.

  15. ALK-rearranged adenocarcinoma with extensive mucin production can mimic mucinous adenocarcinoma: clinicopathological analysis and comprehensive histological comparison with KRAS-mutated mucinous adenocarcinoma.

    PubMed

    Cha, Yoon Jin; Han, Joungho; Hwang, Soo Hyun; Lee, Tae Bum; Kim, Hojoong; Zo, Jea Ill

    2016-06-01

    We aimed to investigate clinicopathological features and histology of ALK-rearranged adenocarcinomas with extensive mucin production (AEM) that mimic mucinous adenocarcinoma (MA). Retrospectively, 12 cases of AEM and 25 cases of MA harbouring KRAS mutation were retrieved. The clinicopathological profile and detailed histological features were analysed and compared based on the ALK and KRAS status. AEMs occurred in younger patients (p = 0.044) and were characterised by floating tubulopapillary pattern (p < 0.001), prominent nucleolus (p < 0.001), and apical cytoplasmic snouts (p < 0.001). In contrast, KRAS-mutated MAs lacked ALK-specific histological patterns (p < 0.05). Instead, tumour-infiltrating leukocytes (p = 0.018) and smooth cytoplasmic borders (p < 0.001) with vesicular nuclei (p = 0.004) were prominent in KRAS-mutated MAs. AEMs demonstrated characteristic tubulopapillary pattern and apical snouts, which were distinguishing features from MAs with KRAS mutation. Apical snouts can be a useful histological surrogate for ALK rearrangement in the pulmonary adenocarcinomas showing extensive mucin that mimic MA. PMID:27114375

  16. Pathology of Mucinous Appendiceal Tumors and Pseudomyxoma Peritonei.

    PubMed

    Ramaswamy, Veena

    2016-06-01

    Neoplasms of the appendix are rare, but because of their unusual presentation and unpredictable biologic behavior, it is important to diagnose them correctly. Mucinous tumors account for 58 % of malignant tumors of appendix in SEER database and the remaining are carcinoids. The mucinous appendiceal tumors have a potential to spread to the peritoneum and viscera in the form of gelatinous material with or without neoplastic cells resulting in Pseudomyxoma peritonei. (PMP) PMP is a clinical entity that has a unique biological behavior and can arise from seemingly benign tumors to frankly malignant ones. Several classifications exist for PMP of which Ronnet's classification has been the most popular. In 2010, the WHO proposed a 2 tier classification that classified PMP as either low grade or high grade based on the presence of mucin, cytological and architectural features. According to this classification when the underlying cause for PMP is an appendiceal tumor it is always a mucinous adenocarcinoma rather than a mucocoele or adenoma and these terms should no longer be used. This system of classification helps in predicting the behavior of the tumor and proper treatment strategies. The understanding of the pathogenesis of the disease has also improved with identification of newer biomarkers and molecular genetic alterations. IHC markers CK 20, CDX2 and MUC2 are found to be positive in these tumors in addition to KRAS mutation and loss of heterozygosity in some gene loci. Proper histopathologic classification and predicting the tumor behavior requires a close interaction between the pathologist and the surgeon. The use of the combined modality treatment of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) has led to a 5-year survival ranging from 62.5 % to 100 % for low grade, and 0 %-65 % for high grade disease. This article focuses on the etiopathogenesis, clinical behavior, diagnosis and classification of mucinous tumors of the

  17. Upper Airway Mechanics

    PubMed Central

    Verbraecken, Johan A.; De Backer, Wilfried A.

    2009-01-01

    This review discusses the pathophysiological aspects of sleep-disordered breathing, with focus on upper airway mechanics in obstructive and central sleep apnoea, Cheyne-Stokes respiration and obesity hypoventilation syndrome. These disorders constitute the end points of a spectrum with distinct yet interrelated mechanisms that lead to substantial pathology, i.e. increased upper airway collapsibility, control of breathing instability, increased work of breathing, disturbed ventilatory system mechanics and neurohormonal changes. Concepts are changing. Although sleep apnoea is considered more and more to be an increased loop gain disorder, the central type of apnoea is now considered as an obstructive event, because it causes pharyngeal narrowing, associated with prolonged expiration. Although a unifying concept for the pathogenesis is lacking, it seems that these patients are in a vicious circle. Knowledge of common patterns of sleep-disordered breathing may help to identify these patients and guide therapy. PMID:19478479

  18. Brachycephalic airway syndrome.

    PubMed

    Meola, Stacy D

    2013-08-01

    Brachycephalic airway syndrome is a common finding in brachycephalic breeds. A combination of primary and secondary changes can progress to life-threatening laryngeal collapse. Early recognition of primary anatomic abnormalities that include stenotic nares, elongated soft palate, and hypoplastic trachea would allow the clinician to make early recommendations for medical and surgical management, which can improve the quality of life in affected animals. PMID:24182996

  19. Upper airway resistance syndrome.

    PubMed

    Hasan, N; Fletcher, E C

    1998-07-01

    Many clinicians are familiar with the clinical symptoms and signs of obstructive sleep apnea (OSA). In its most blatant form, OSA is complete airway obstruction with repetitive, prolonged pauses in breathing, arterial oxyhemoglobin desaturation; followed by arousal with resumption of breathing. Daytime symptoms of this disorder include excessive daytime somnolence, intellectual dysfunction, and cardiovascular effects such as systemic hypertension, angina, myocardial infarction, and stroke. It has been recently recognized that increased pharyngeal resistance with incomplete obstruction can lead to a constellation of symptoms identical to OSA called "upper airway resistance syndrome" (UARS). The typical findings of UARS on sleep study are: (1) repetitive arousals from EEG sleep coinciding with a (2) waxing and waning of the respiratory airflow pattern and (3) increased respiratory effort as measured by esophageal pressure monitoring. There may be few, if any, obvious apneas or hypopneas with desaturation, but snoring may be a very prominent finding. Treatment with nasal positive airway pressure (NCPAP) eliminates the symptoms and confirms the diagnosis. Herein we describe two typical cases of UARS. PMID:9676067

  20. Airway closure in microgravity.

    PubMed

    Dutrieue, Brigitte; Verbanck, Sylvia; Darquenne, Chantal; Prisk, G Kim

    2005-08-25

    Recent single breath washout (SBW) studies in microgravity and on the ground have suggested an important effect of airway closure on gas mixing in the human lung, reflected particularly in the phase III slope of vital capacity SBW and bolus tests. In order to explore this effect, we designed a SBW in which subjects inspired 2-l from residual volume (RV) starting with a 150 ml bolus of He and SF6. In an attempt to vary the pattern of airways closure configuration before the test, the experiments were conducted in 1G and in microgravity during parabolic flight allowing the pre-test expiration to RV to be either in microgravity or at 1.8 G, with the actual test gas inhalation performed entirely in microgravity. Contrary to our expectations, the measured phase III slope and phase IV height and volume obtained from seven subjects in microgravity were essentially identical irrespective of the gravity level during the pre-test expiration to RV. The results suggest that airway closure configuration at RV before the test inspiration has no apparent impact on phases III and IV generation. PMID:15979418

  1. Specific allergen immunotherapy attenuates allergic airway inflammation in a rat model of Alstonia scholaris pollen induced airway allergy.

    PubMed

    Datta, Ankur; Moitra, Saibal; Hazra, Iman; Mondal, Somnath; Das, Prasanta Kumar; Singh, Manoj Kumar; Chaudhuri, Suhnrita; Bhattacharya, Debanjan; Tripathi, Santanu Kumar; Chaudhuri, Swapna

    2016-01-01

    Pollen grains are well established to be an important cause of respiratory allergy. Current pharmacologic therapies for allergic asthma do not cure the disease. Allergen specific immunotherapy is the only treatment method which re-directs the immune system away from allergic response leading to a long lasting effect. The mechanism by which immunotherapy achieves this goal is an area of active research world-wide. The present experimental study was designed to develop an experimental model of allergic lung inflammation based on a relevant human allergen, Alstonia scholaris pollen, and to establish the immunological and cellular features of specific allergen immunotherapy using this same pollen extract. Our results revealed that Alstonia scholaris pollen sensitization and challenge causes eosinophilic airway inflammation with mucin hypersecretion. This is associated with increased total IgE, increased expression of FcɛRI on lung mast cells and increased levels of IL-4, IL-5 & IL-13 as confirmed by ELISA, in-situ immunofluorescence and FACS assay. Allergen specific immunotherapy reduced airway inflammation and also decreased total IgE level, FcɛRI expression, IL-4, IL-5 & IL-13 levels. It was further noted that the reduction of these levels was more by intra-nasal route than by intra-peritoneal route. Thus we present a novel animal model of Alstonia scholaris pollen allergic disease and specific allergen immunotherapy which will pave the way towards the development of better treatment modalities. PMID:26667977

  2. Structural investigation of porcine stomach mucin by X-ray fiber diffraction and homology modeling

    SciTech Connect

    Veluraja, K.; Vennila, K.N.; Umamakeshvari, K.; Jasmine, A.; Velmurugan, D.

    2011-03-25

    Research highlights: {yields} Techniques to get oriented mucin fibre. {yields} X-ray fibre diffraction pattern for mucin. {yields} Molecular modeling of mucin based on X-ray fibre diffraction pattern. -- Abstract: The basic understanding of the three dimensional structure of mucin is essential to understand its physiological function. Technology has been developed to achieve orientated porcine stomach mucin molecules. X-ray fiber diffraction of partially orientated porcine stomach mucin molecules show d-spacing signals at 2.99, 4.06, 4.22, 4.7, 5.37 and 6.5 A. The high intense d-spacing signal at 4.22 A is attributed to the antiparallel {beta}-sheet structure identified in the fraction of the homology modeled mucin molecule (amino acid residues 800-980) using Nidogen-Laminin complex structure as a template. The X-ray fiber diffraction signal at 6.5 A reveals partial organization of oligosaccharides in porcine stomach mucin. This partial structure of mucin will be helpful in establishing a three dimensional structure for the whole mucin molecule.

  3. Rat and human colonic mucins bind to and inhibit adherence lectin of Entamoeba histolytica.

    PubMed Central

    Chadee, K; Petri, W A; Innes, D J; Ravdin, J I

    1987-01-01

    Establishment of adherence by Entamoeba histolytica is mediated by a 170-kD Gal/GalNAc inhibitable lectin and is required for cytolysis and phagocytosis of mammalian target cells. We studied the biochemical mechanisms of the in vitro interaction between rat and human colonic mucins and axenic E. histolytica trophozoites. Crude mucus prevented amebic adherence to Chinese hamster ovary (CHO) cells by up to 70%. Purification of the colonic mucins by Sepharose 4B chromatography, nuclease digestion, and cesium chloride gradient centrifugation resulted in a 1,000-fold enrichment of the inhibitory mucins. Purified rat mucin inhibited amebic adherence to and cytolysis of homologous rat colonic epithelial cells. Oxidation and enzymatic cleavage of rat mucin Gal and GalNAc residues completely abrogated mucin inhibition of amebic adherence. The binding of rat 125I-mucin to amebae was galactose specific, saturable, reversible, and pH dependent. A monoclonal antibody specific for the 170-kD amebic Gal/GalNAc lectin completely inhibited the binding of rat 125I-mucin. Rat mucin bound to Affigel affinity purified the amebic lectin from conditioned medium. Colonic mucin glycoproteins act as an important host defense by binding to the parasite's adherence lectin, thus preventing amebic attachment to and cytolysis of host epithelial cells. Images PMID:2890655

  4. A procedure for Alcian blue staining of mucins on polyvinylidene difluoride membranes.

    PubMed

    Dong, Weijie; Matsuno, Yu-ki; Kameyama, Akihiko

    2012-10-16

    The isolation and characterization of mucins are critically important for obtaining insight into the molecular pathology of various diseases, including cancers and cystic fibrosis. Recently, we developed a novel membrane electrophoretic method, supported molecular matrix electrophoresis (SMME), which separates mucins on a polyvinylidene difluoride (PVDF) membrane impregnated with a hydrophilic polymer. Alcian blue staining is widely used to visualize mucopolysaccharides and acidic mucins on both blotted membranes and SMME membranes; however, this method cannot be used to stain mucins with a low acidic glycan content. Meanwhile, periodic acid-Schiff staining can selectively visualize glycoproteins, including mucins, but is incompatible with glycan analysis, which is indispensable for mucin characterizations. Here we describe a novel staining method, designated succinylation-Alcian blue staining, for visualizing mucins on a PVDF membrane. This method can visualize mucins regardless of the acidic residue content and shows a sensitivity 2-fold higher than that of Pro-Q Emerald 488, a fluorescent periodate Schiff-base stain. Furthermore, we demonstrate the compatibility of this novel staining procedure with glycan analysis using porcine gastric mucin as a model mucin. PMID:22950532

  5. An evaluation of the morphologic features of low-grade mucinous neoplasms of the appendix metastatic in the ovary, and comparison with primary ovarian mucinous tumors.

    PubMed

    Stewart, Colin J R; Ardakani, Nima M; Doherty, Dorota A; Young, Robert H

    2014-01-01

    It may be difficult to distinguish ovarian involvement by a low-grade appendiceal mucinous neoplasm (LAMN) from a primary gastrointestinal-type primary borderline (proliferative) ovarian tumor (IBMT) or an ovarian mucinous tumor arising within a teratoma, particularly when the latter is associated with mucinous ascites/pseudomyxoma peritonei. We noted that LAMNs involving the ovaries show 2 distinctive histologic features, "scalloped" glands and subepthelial stromal clefts, whereas IBMTs more often are associated with reactive cellular stroma and histiocyte aggregates (mucin granulomas). The frequency of these features was investigated in 18 LAMNs (16 with pseudomyxoma peritonei), 18 primary IBMTs, and 6 teratoma-associated mucinous tumors (selected on the basis of associated pseudomyxoma peritonei). Scalloped glands and subepithelial clefts were identified in 17 and 16 LAMNs, respectively, and in 3 and 7 IBMTs, respectively. Conversely, reactive stroma and histiocyte aggregates were present in 2 and 0 LAMNs, respectively, and in 11 and 10 IBMTs, respectively. LAMNs were often bilateral (12/18 cases) and they more frequently showed mucin dissection of the ovarian stroma and tall mucin-rich (hypermucinous) epithelial cells compared with IBMTs. Our findings suggest that scalloped glands, subepithelial clefts, cellular stroma, and histiocyte aggregates may be useful additional morphologic parameters to help distinguish these tumor types. However, teratoma-associated mucinous neoplasms can show identical histologic features to those of LAMNs involving the ovary, and therefore accurate diagnosis of such cases requires careful macroscopic and microscopic examinations of the ovaries together with complete histologic assessment of the appendix. PMID:24300528

  6. Muc5ac gastric mucin glycosylation is shaped by FUT2 activity and functionally impacts Helicobacter pylori binding

    PubMed Central

    Magalhães, Ana; Rossez, Yannick; Robbe-Masselot, Catherine; Maes, Emmanuel; Gomes, Joana; Shevtsova, Anna; Bugaytsova, Jeanna; Borén, Thomas; Reis, Celso A.

    2016-01-01

    The gastrointestinal tract is lined by a thick and complex layer of mucus that protects the mucosal epithelium from biochemical and mechanical aggressions. This mucus barrier confers protection against pathogens but also serves as a binding site that supports a sheltered niche of microbial adherence. The carcinogenic bacteria Helicobacter pylori colonize the stomach through binding to host glycans present in the glycocalyx of epithelial cells and extracellular mucus. The secreted MUC5AC mucin is the main component of the gastric mucus layer, and BabA-mediated binding of H. pylori to MUC5AC confers increased risk for overt disease. In this study we unraveled the O-glycosylation profile of Muc5ac from glycoengineered mice models lacking the FUT2 enzyme and therefore mimicking a non-secretor human phenotype. Our results demonstrated that the FUT2 determines the O-glycosylation pattern of Muc5ac, with Fut2 knock-out leading to a marked decrease in α1,2-fucosylated structures and increased expression of the terminal type 1 glycan structure Lewis-a. Importantly, for the first time, we structurally validated the expression of Lewis-a in murine gastric mucosa. Finally, we demonstrated that loss of mucin FUT2-mediated fucosylation impairs gastric mucosal binding of H. pylori BabA adhesin, which is a recognized feature of pathogenicity. PMID:27161092

  7. Murine Cytomegalovirus Influences Foxj1 Expression, Ciliogenesis, and Mucus Plugging in Mice with Allergic Airway Disease

    PubMed Central

    Wu, Carol A.; Peluso, John J.; Shanley, John D.; Puddington, Lynn; Thrall, Roger S.

    2008-01-01

    We have followed throughout time the development of allergic airway disease (AAD) in both uninfected mice and mice infected intranasally with murine cytomegalovirus (MCMV). Histological evaluation of lung tissue from uninfected mice with AAD demonstrated mucus plugging after 14 and 21 days of ovalbumin-aerosol challenge, with resolution of mucus plugging occurring by 42 days. In MCMV/AAD mice, mucus plugging was observed after 7 days of ovalbumin-aerosol challenge and remained present at 42 days. The level of interleukin-13 in bronchoalveolar lavage fluid from MCMV/AAD mice was decreased compared with AAD mice and was accompanied by increased levels of interferon-γ. Levels of Muc5A/C, Muc5B, or Muc2 mucin mRNA in the lungs of MCMV/AAD mice were not elevated compared with AAD mice. MCMV was able to infect the airway epithelium, resulting in decreased expression of Foxj1, a transcription factor critical for ciliogenesis, and a loss of ciliated epithelial cells. In addition, an increase in the number of epithelial cells staining positive for periodic acid-Schiff was observed in MCMV/AAD airways. Together, these findings suggest that MCMV infection of the airway epithelium enhances goblet cell metaplasia and diminishes efficient mucociliary clearance in mice with AAD, resulting in increased mucus plugging. PMID:18258850

  8. In Vitro Spatial and Temporal Analysis of Mycoplasma pneumoniae Colonization of Human Airway Epithelium

    PubMed Central

    Prince, Oliver A.; Krunkosky, Thomas M.

    2014-01-01

    Mycoplasma pneumoniae is an important cause of respiratory disease, especially in school-age children and young adults. We employed normal human bronchial epithelial (NHBE) cells in air-liquid interface culture to study the interaction of M. pneumoniae with differentiated airway epithelium. These airway cells, when grown in air-liquid interface culture, polarize, form tight junctions, produce mucus, and develop ciliary function. We examined both qualitatively and quantitatively the role of mycoplasma gliding motility in the colonization pattern of developing airway cells, comparing wild-type M. pneumoniae and mutants thereof with moderate to severe defects in gliding motility. Adherence assays with radiolabeled mycoplasmas demonstrated a dramatic reduction in binding for all strains with airway cell polarization, independent of acquisition of mucociliary function. Adherence levels dropped further once NHBE cells achieved terminal differentiation, with mucociliary activity strongly selecting for full gliding competence. Analysis over time by confocal microscopy demonstrated a distinct colonization pattern that appeared to originate primarily with ciliated cells, but lateral spread from the base of the cilia was slower than expected. The data support a model in which the mucociliary apparatus impairs colonization yet cilia provide a conduit for mycoplasma access to the host cell surface and suggest acquisition of a barrier function, perhaps associated with tethered mucin levels, with NHBE cell polarization. PMID:24478073

  9. γδ T-cell-deficient mice show alterations in mucin expression, glycosylation, and goblet cells but maintain an intact mucus layer.

    PubMed

    Kober, Olivia I; Ahl, David; Pin, Carmen; Holm, Lena; Carding, Simon R; Juge, Nathalie

    2014-04-01

    Intestinal homeostasis is maintained by a hierarchy of immune defenses acting in concert to minimize contact between luminal microorganisms and the intestinal epithelial cell surface. The intestinal mucus layer, covering the gastrointestinal tract epithelial cells, contributes to mucosal homeostasis by limiting bacterial invasion. In this study, we used γδ T-cell-deficient (TCRδ(-/-)) mice to examine whether and how γδ T-cells modulate the properties of the intestinal mucus layer. Increased susceptibility of TCRδ(-/-) mice to dextran sodium sulfate (DSS)-induced colitis is associated with a reduced number of goblet cells. Alterations in the number of goblet cells and crypt lengths were observed in the small intestine and colon of TCRδ(-/-) mice compared with C57BL/6 wild-type (WT) mice. Addition of keratinocyte growth factor to small intestinal organoid cultures from TCRδ(-/-) mice showed a marked increase in crypt growth and in both goblet cell number and redistribution along the crypts. There was no apparent difference in the thickness or organization of the mucus layer between TCRδ(-/-) and WT mice, as measured in vivo. However, γδ T-cell deficiency led to reduced sialylated mucins in association with increased gene expression of gel-secreting Muc2 and membrane-bound mucins, including Muc13 and Muc17. Collectively, these data provide evidence that γδ T cells play an important role in the maintenance of mucosal homeostasis by regulating mucin expression and promoting goblet cell function in the small intestine. PMID:24503767

  10. 21 CFR 868.5110 - Oropharyngeal airway.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5110 Oropharyngeal airway. (a... provide a patent airway. (b) Classification. Class I (general controls). The device is exempt from...

  11. 21 CFR 868.5110 - Oropharyngeal airway.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Therapeutic Devices § 868.5110 Oropharyngeal airway. (a... provide a patent airway. (b) Classification. Class I (general controls). The device is exempt from...

  12. Enzymatically active biomimetic micropropellers for the penetration of mucin gels

    PubMed Central

    Walker, Debora; Käsdorf, Benjamin T.; Jeong, Hyeon-Ho; Lieleg, Oliver; Fischer, Peer

    2015-01-01

    In the body, mucus provides an important defense mechanism by limiting the penetration of pathogens. It is therefore also a major obstacle for the efficient delivery of particle-based drug carriers. The acidic stomach lining in particular is difficult to overcome because mucin glycoproteins form viscoelastic gels under acidic conditions. The bacterium Helicobacter pylori has developed a strategy to overcome the mucus barrier by producing the enzyme urease, which locally raises the pH and consequently liquefies the mucus. This allows the bacteria to swim through mucus and to reach the epithelial surface. We present an artificial system of reactive magnetic micropropellers that mimic this strategy to move through gastric mucin gels by making use of surface-immobilized urease. The results demonstrate the validity of this biomimetic approach to penetrate biological gels, and show that externally propelled microstructures can actively and reversibly manipulate the physical state of their surroundings, suggesting that such particles could potentially penetrate native mucus. PMID:26824056

  13. Synthetic Oral Mucin Mimic from Polymer Micelle Networks

    PubMed Central

    2015-01-01

    Mucin networks are formed in the oral cavity by complexation of glycoproteins with other salivary proteins, yielding a hydrated lubricating barrier. The function of these networks is linked to their structural, chemical, and mechanical properties. Yet, as these properties are interdependent, it is difficult to tease out their relative importance. Here, we demonstrate the ability to recreate the fibrous like network through a series of complementary rinses of polymeric worm-like micelles, resulting in a 3-dimensional (3D) porous network that can be deposited layer-by-layer onto any surface. In this work, stability, structure, and microbial capture capabilities were evaluated as a function of network properties. It was found that network structure alone was sufficient for bacterial capture, even with networks composed of the adhesion-resistant polymer, poly(ethylene glycol). The synthetic networks provide an excellent, yet simple, means of independently characterizing mucin network properties (e.g., surface chemistry, stiffness, and pore size). PMID:24992241

  14. [Microbiocenosis of parietal mucin in the gastrointestinal tract of rats].

    PubMed

    Vorob'ev, A A; Nesvizhskiĭ, Iu V; Bogdanova, E A; Korneev, L M

    2005-01-01

    The qualitative and quantitative composition of the microbial community in parietal mucin at different areas of the gastrointestinal tract (GIT) of rats was revealed. The pronounced variability in the quantitative and qualitative characteristics of microbiocenosis in parietal mucin of rats at different sections was revealed. The differences were most pronounced in the passage from upper to lower GIT sections, the large intestine found to be the richest biocenosis. The microbial composition of rat feces was faintly associated with the GIT parietal microbiocenosis. The individual areas of GIT mucosa were unique of their microbial characteristics and organization. This makes it possible to regard them as relatively independent biotopes and indicates that it is impossible to evaluate the microbial community by one of the colonic mucosal sifes. PMID:16438365

  15. Influence of exercise on airway epithelia in cystic fibrosis: a review.

    PubMed

    Cholewa, Jason Michael; Paolone, Vincent J

    2012-07-01

    Regular exercise is recommended as part of cystic fibrosis (CF) physiotherapy. Exercise delays the development of pulmonary disease in CF patients; however, the cellular mechanisms responsible for these improvements are unclear. This review expands on the hypothesis that exercise improves CF pathophysiological ion dysregulation via purinergic and adrenergic pathways by describing the effects of 5' adenosine monophosphate-activated protein kinase (AMPK), atrial natriuretic peptide (ANP), and arginine-vasopressin (AVP) on CF airway epithelia. Activation of AMPK decreases Na(+) absorption, increases airway surface liquid, and reduces oxidative stress and inflammation. Plasma ANP inhibits the basolateral Na(+)/K(+)-ATPase and may therefore reduce epithelial water absorption. Airway epithelia respond to plasma AVP and secrete AVP in response to elevated bradykinin. AVP stimulates the basolateral Na(+)/K(+)/2Cl(-) exchanger, thereby increasing Cl(-) secretion, reducing Na(+) absorption, and promoting basolateral to luminal water flux. In addition, AVP may increase cilia beat frequency in airway epithelia via a Ca(2+)-dependent mechanism. This review will describe the effects of exercise on AMPK activation, ANP release, and AVP secretion; we hypothesize that the mechanical and metabolic perturbations that occur with exercise may be beneficial in preventing CF lung pathogenesis by improving airway hydration, mucociliary clearance, and reducing markers of inflammation. PMID:22297805

  16. Chemical modification of carbohydrates in tissue sections may unmask mucin antigens.

    PubMed

    Kirkeby, S

    2013-01-01

    Expression of mucins in cells and tissues is of great diagnostic and prognostic importance, and immunohistochemistry frequently is used to detect them. Reports concerning mucin localization in sections sometimes are conflicting, however, partly because immunogenic regions of the mucin molecule may be masked and thus not available for binding to an antibody. We modified carbohydrates in tissue sections chemically to enhance the binding of monoclonal mucin antibodies and of the lectin, Vicia villosa B4, to human tissue. The immunohistochemical localization of MUC1 and the simple mucin-type antigens, Tn and sialyl-Tn, was influenced by oxidation with periodic acid and by β-elimination before incubation. In some epithelial cells the staining was prevented by these procedures while in other cells it was evident. It appears that chemical modification can either destroy some antigen binding sites or unmask cryptic antigen binding sites in the mucin molecule and thereby make them accessible for immunohistochemical detection. PMID:22998734

  17. S100P is a useful marker for differentiation of ovarian mucinous tumors.

    PubMed

    Umezaki, Y; Ito, M; Nakashima, M; Mihara, Y; Naruke, Y; Kurohama, H; Yatsunami, N; Yasuhi, I

    2015-01-01

    The S100P protein stimulates cell proliferation and survival, thereby contributing to tumor progression. The purpose of this study was to evaluate S100P expression in the three subtypes of mucinous cystic tumors, cystadenomas, borderline tumors, and adenocarcinomas. The authors examined nuclear S100P expression in 60 mucinous ovarian tumor specimens, including 24 specimens of mucinous cystadenoma, 15 of borderline tumors, and 21 of adenocarcinomas. Immunohistochemistry revealed S100P expression followed one of three patterns: (1) Expressed in most nuclei of mucinous epithelial cells, (2) sporadic (spotted or patchy) expression, or (3) absent or rarely expressed in the nuclei of mucinous epithelial cells. Most adenomas showed the first expression pattern, and borderline tumors often showed a patchy expression pattern. Adenocarcinomas generally demonstrated absence of S100P expression. These data suggest that S100P is a useful histological marker to differentiate between benign, borderline, and malignant mucinous tumors of the ovary. PMID:26050349

  18. Brachycephalic airway obstructive syndrome.

    PubMed

    Wykes, P M

    1991-06-01

    This is a complex condition, recognized primarily in brachycephalic breeds, that results in varying degrees of upper airway obstruction. The signs consist of respiratory distress, stridor, reduced exercise tolerance, and in more severe cases, cyanosis and collapse. The inherent anatomy of the brachycephalic skull contributes to the development of these signs. Such anatomic features include: a shortened and distorted nasopharynx, stenotic nares, an elongated soft palate, and everted laryngeal saccules. The increased negative pressure created in the pharyngolaryngeal region, as a result of these obstructing structures, ultimately results in distortion and collapse of the arytenoid cartilages of the larynx. PMID:1802247

  19. Particle Deposition During Airway Closure

    NASA Astrophysics Data System (ADS)

    Tai, Cheng-Feng; Halpern, David; Grotberg, James B.

    2011-11-01

    Inhaled aerosol particles deposit in the lung and may be from environmental, toxic, or medical therapy sources. While much research focuses on inspiratory deposition, primarily at airway bifurcations due to inertial impaction, there are other mechanisms that allow the particles to reach the airway surface, such as gravitational settling and diffusion depending on particle size. We introduce a new mechanism not previously studied, i.e. aerosol deposition from airway closure. The airways are lined with a liquid layer. Due to the surface tension driven instability, a liquid plug can form from this layer which blocks the airway. This process of airway closure tends to occur toward the end of expiration. In this study, the efficiency of the impaction of the particles during airway closure will be investigated. The particles will be released from the upstream of the airway and convected by the air flow and deposited onto the closing liquid layer. We solve the governing equations using a finite volume approach in conjunction with a sharp interface method for the interfaces. Once the velocity field of the gas flow is obtained, the path of the particles will be calculated and the efficiency of the deposition can be estimated. We acknowledge support from the National Institutes of Health grant number NIH HL85156.

  20. [Intraductal papillary mucinous neoplasia: which findings support observation?].

    PubMed

    Mayerle, J; Kraft, M; Menges, P; Simon, P; Ringel, J; Partecke, L I; Heidecke, C D; Lerch, M M

    2012-02-01

    On abdominal CT scans asymptomatic cystic lesions of the pancreas are accidentally detected in 1-2% of patients. Congenital cysts and pancreatic pseudocysts account for two thirds of these lesions. Pancreatic pseudocysts are a frequent complication of acute and chronic pancreatitis. Among resected cystic neoplasms serous cystic adenoma accounts for 30%, mucinous cystic neoplasms for 45% and intraductal papillary mucinous neoplasms for 25%. The diagnosis of a cystic pancreatic lesion is usually made by diagnostic imaging. Symptomatic lesions require definitive therapeutic treatment after appropriate diagnostic work-up. In the diagnosis of asymptomatic cystic lesions several factors are important, among them whether the cyst is connected to the pancreatic duct (as in IPMN and pseudocysts), the size of lesion (for treatment indications) and whether nodules form in the wall of the cyst (a sign of potential malignancy). EUS-guided fine needle aspiration of the cyst fluid adds to the discrimination between benign, premalignant and malignant cystic lesions. Measuring lipase activity, CEA, viscosity and mucin as well as cytology can help in differentiating cystic lesions. An algorithm is discussed for the differential diagnosis and for selection of the appropriate treatment for pancreatic cystic lesions, most of which never require surgery. PMID:22271054

  1. Diffusion through Pig Gastric Mucin: Effect of Relative Humidity

    PubMed Central

    Runnsjö, Anna; Dabkowska, Aleksandra P.; Sparr, Emma; Kocherbitov, Vitaly; Arnebrant, Thomas; Engblom, Johan

    2016-01-01

    Mucus covers the epithelium found in all intestinal tracts, where it serves as an important protecting barrier, and pharmaceutical drugs administrated by the oral, rectal, vaginal, ocular, or nasal route need to penetrate the mucus in order to reach their targets. Furthermore, the diffusion in mucus as well as the viscosity of mucus in the eyes, nose and throat can change depending on the relative humidity of the surrounding air. In this study we have investigated how diffusion through gels of mucin, the main protein in mucus, is affected by changes in ambient relative humidity (i.e. water activity). Already a small decrease in water activity was found to give rise to a significant decrease in penetration rate through the mucin gel of the antibacterial drug metronidazole. We also show that a decrease in water activity leads to decreased diffusion rate in the mucin gel for the fluorophore fluorescein. This study shows that it is possible to alter transport rates of molecules through mucus by changing the water activity in the gel. It furthermore illustrates the importance of considering effects of the water activity in the mucosa during development of potential pharmaceuticals. PMID:27336158

  2. Mucins help to avoid alloreactivity at the maternal fetal interface.

    PubMed

    Redzovic, Arnela; Laskarin, Gordana; Dominovic, Marin; Haller, Herman; Rukavina, Daniel

    2013-01-01

    During gestation, many different mechanisms act to render the maternal immune system tolerant to semi-allogeneic trophoblast cells of foetal origin, including those mediated via mucins that are expressed during the peri-implantation period in the uterus. Tumour- associated glycoprotein-72 (TAG-72) enhances the already established tolerogenic features of decidual dendritic cells with the inability to progress towards Th1 immune orientation due to lowered interferon (IFN)- γ and interleukin (IL)-15 expression. Mucine 1 (Muc 1) supports alternative activation of decidual macrophages, restricts the proliferation of decidual regulatory CD56(+) bright natural killer (NK) cells, and downregulates their cytotoxic potential, including cytotoxic mediator protein expression. Removing TAG-72 and Muc 1 from the eutopic implantation site likely contributes to better control of trophoblast invasion by T cells and NK cells and appears to have important immunologic advantages for successful implantation, in addition to mechanical advantages. However, these processes may lead to uncontrolled trophoblast growth after implantation, inefficient defence against infection or tumours, and elimination of unwanted immunocompetent cells at the maternal-foetal interface. The use of mucins by tumour cells to affect the local microenvironment in order to avoid the host immune response and to promote local tumour growth, invasion, and metastasis confirms this postulation. PMID:23864879

  3. Tea derived galloylated polyphenols cross-link purified gastrointestinal mucins.

    PubMed

    Georgiades, Pantelis; Pudney, Paul D A; Rogers, Sarah; Thornton, David J; Waigh, Thomas A

    2014-01-01

    Polyphenols derived from tea are thought to be important for human health. We show using a combination of particle tracking microrheology and small-angle neutron scattering that polyphenols acts as cross-linkers for purified gastrointestinal mucin, derived from the stomach and the duodenum. Both naturally derived purified polyphenols, and green and black tea extracts are shown to act as cross-linkers. The main active cross-linking component is found to be the galloylated forms of catechins. The viscosity, elasticity and relaxation time of the mucin solutions experience an order of magnitude change in value upon addition of the polyphenol cross-linkers. Similarly small-angle neutron scattering experiments demonstrate a sol-gel transition with the addition of polyphenols, with a large increase in the scattering at low angles, which is attributed to the formation of large scale (>10 nm) heterogeneities during gelation. Cross-linking of mucins by polyphenols is thus expected to have an impact on the physicochemical environment of both the stomach and duodenum; polyphenols are expected to modulate the barrier properties of mucus, nutrient absorption through mucus and the viscoelastic microenvironments of intestinal bacteria. PMID:25162539

  4. Salivary Mucins Protect Surfaces from Colonization by Cariogenic Bacteria

    PubMed Central

    Frenkel, Erica Shapiro

    2014-01-01

    Understanding how the body's natural defenses function to protect the oral cavity from the myriad of bacteria that colonize its surfaces is an ongoing topic of research that can lead to breakthroughs in treatment and prevention. One key defense mechanism on all moist epithelial linings, such as the mouth, gastrointestinal tract, and lungs, is a layer of thick, well-hydrated mucus. The main gel-forming components of mucus are mucins, large glycoproteins that play a key role in host defense. This study focuses on elucidating the connection between MUC5B salivary mucins and dental caries, one of the most common oral diseases. Dental caries is predominantly caused by Streptococcus mutans attachment and biofilm formation on the tooth surface. Once S. mutans attaches to the tooth, it produces organic acids as metabolic by-products that dissolve tooth enamel, leading to cavity formation. We utilize CFU counts and fluorescence microscopy to quantitatively show that S. mutans attachment and biofilm formation are most robust in the presence of sucrose and that aqueous solutions of purified human MUC5B protect surfaces by acting as an antibiofouling agent in the presence of sucrose. In addition, we find that MUC5B does not alter S. mutans growth and decreases surface attachment and biofilm formation by maintaining S. mutans in the planktonic form. These insights point to the importance of salivary mucins in oral health and lead to a better understanding of how MUC5B could play a role in cavity prevention or diagnosis. PMID:25344244

  5. A distinct molecular profile associated with mucinous epithelial ovarian cancer

    PubMed Central

    Heinzelmann-Schwarz, V A; Gardiner-Garden, M; Henshall, S M; Scurry, J P; Scolyer, R A; Smith, A N; Bali, A; Bergh, P Vanden; Baron-Hay, S; Scott, C; Fink, D; Hacker, N F; Sutherland, R L; O'Brien, P M

    2006-01-01

    Mucinous epithelial ovarian cancers (MOC) are clinically and morphologically distinct from the other histological subtypes of ovarian cancer. To determine the genetic basis of MOC and to identify potential tumour markers, gene expression profiling of 49 primary ovarian cancers of different histological subtypes was performed using a customised oligonucleotide microarray containing >59 000 probesets. The results show that MOC express a genetic profile that both differs and overlaps with other subtypes of epithelial ovarian cancer. Concordant with its histological phenotype, MOC express genes characteristic of mucinous carcinomas of varying epithelial origin, including intestinal carcinomas. Differences in gene expression between MOC and other histological subtypes of ovarian cancer were confirmed by RT–PCR and/or immunohistochemistry. In particular, galectin 4 (LGALS4) was highly and specifically expressed in MOC, but expressed at lower levels in benign mucinous cysts and borderline (atypical proliferative) tumours, supporting a malignant progression model of MOC. Hence LGALS4 may have application as an early and differential diagnostic marker of MOC. PMID:16508639

  6. Mucin Agarose Gel Electrophoresis: Western Blotting for High-molecular-weight Glycoproteins.

    PubMed

    Ramsey, Kathryn A; Rushton, Zachary L; Ehre, Camille

    2016-01-01

    Mucins, the heavily-glycosylated proteins lining mucosal surfaces, have evolved as a key component of innate defense by protecting the epithelium against invading pathogens. The main role of these macromolecules is to facilitate particle trapping and clearance while promoting lubrication of the mucosa. During protein synthesis, mucins undergo intense O-glycosylation and multimerization, which dramatically increase the mass and size of these molecules. These post-translational modifications are critical for the viscoelastic properties of mucus. As a result of the complex biochemical and biophysical nature of these molecules, working with mucins provides many challenges that cannot be overcome by conventional protein analysis methods. For instance, their high-molecular-weight prevents electrophoretic migration via regular polyacrylamide gels and their sticky nature causes adhesion to experimental tubing. However, investigating the role of mucins in health (e.g., maintaining mucosal integrity) and disease (e.g., hyperconcentration, mucostasis, cancer) has recently gained interest and mucins are being investigated as a therapeutic target. A better understanding of the production and function of mucin macromolecules may lead to novel pharmaceutical approaches, e.g., inhibitors of mucin granule exocytosis and/or mucolytic agents. Therefore, consistent and reliable protocols to investigate mucin biology are critical for scientific advancement. Here, we describe conventional methods to separate mucin macromolecules by electrophoresis using an agarose gel, transfer protein into nitrocellulose membrane, and detect signal with mucin-specific antibodies as well as infrared fluorescent gel reader. These techniques are widely applicable to determine mucin quantitation, multimerization and to test the effects of pharmacological compounds on mucins. PMID:27341489

  7. Palliative Surgical Approach in Advanced Nonresponsive Mucinous Ovarian Cancer: A Rare Case Report

    PubMed Central

    Agarwal, Manika; Kumar, Ritesh; Topno, Noor; Mishra, Shweta; Dhirasaria, Ashish; Singh, A Santa

    2016-01-01

    Advanced mucinous ovarian cancer is a separate entity and has different biological behaviour. There is a wide range of therapeutic challenges and dilemmas in the management of these patients. The authors present a case of advanced ovarian mucinous cystadenocarcinoma with pseudomyxoma peritonei who had poor response to standard neoadjuvant chemotherapy. This case is highlighted to emphasize the challenges in the decision making for the management of advanced mucinous ovarian cancer. PMID:27162429

  8. Operative endoscopy of the airway

    PubMed Central

    Walters, Dustin M.

    2016-01-01

    Airway endoscopy has long been an important and useful tool in the management of thoracic diseases. As thoracic specialists have gained experience with both flexible and rigid bronchoscopic techniques, the technology has continued to evolve so that bronchoscopy is currently the foundation for diagnosis and treatment of many thoracic ailments. Airway endoscopy plays a significant role in the biopsy of tumors within the airways, mediastinum, and lung parenchyma. Endoscopic methods have been developed to treat benign and malignant airway stenoses and tracheomalacia. And more recently, techniques have been conceived to treat end-stage emphysema and prolonged air leaks in select patients. This review describes the abundant uses of airway endoscopy, as well as technical considerations and limitations of the current technologies. PMID:26981263

  9. Lubiprostone targets prostanoid EP4 receptors in ovine airways

    PubMed Central

    Cuthbert, AW

    2011-01-01

    BACKGROUND AND PURPOSE Lubiprostone, a prostaglandin E1 derivative, is reported to activate ClC-2 chloride channels located in the apical membranes of a number of transporting epithelia. Lack of functioning CFTR chloride channels in epithelia is responsible for the genetic disease cystic fibrosis, therefore, surrogate channels that can operate independently of CFTR are of interest. This study explores the target receptor(s) for lubiprostone in airway epithelium. EXPERIMENTAL APPROACH All experiments were performed on the ventral tracheal epithelium of sheep. Epithelia were used to measure anion secretion from the apical surface as short circuit current or as fluid secretion from individual airway submucosal glands, using an optical method. KEY RESULTS The EP4 antagonists L-161982 and GW627368 inhibited short circuit current responses to lubiprostone, while EP1,2&3 receptor antagonists were without effect. Similarly, lubiprostone induced secretion in airway submucosal glands was inhibited by L-161982. L-161982 effectively competed with lubiprostone with a Kd value of 0.058 µM, close to its value for binding to human EP4 receptors (0.024 µM). The selective EP4 agonist L-902688 and lubiprostone behaved similarly with respect to EP4 receptor antagonists. Results of experiments with H89, a protein kinase A inhibitor, were consistent with lubiprostone acting through a Gs-protein coupled EP4 receptor/cAMP cascade. CONCLUSIONS AND IMPLICATIONS Lubiprostone-induced short-circuit currents and submucosal gland secretions were inhibited by selective EP4 receptor antagonists. The results suggest EP4 receptor activation by lubiprostone triggers cAMP production necessary for CFTR activation and the secretory responses, a possibility precluded in CF tissues. PMID:20883477

  10. Deoxycholic acid induces the overexpression of intestinal mucin, MUC2, via NF-kB signaling pathway in human esophageal adenocarcinoma cells

    PubMed Central

    Wu, JianTao; Gong, Jun; Geng, Juan; Song, YinXue

    2008-01-01

    Background Mucin alterations are a common feature of esophageal neoplasia, and alterations in MUC2 mucin have been associated with tumor progression in the esophagus. Bile acids have been linked to esophageal adenocarcinoma and mucin secretion, but their effects on mucin gene expression in human esophageal adenocarcinoma cells is unknown. Methods Human esophageal adenocarcinoma cells were treated 18 hours with 50–300 μM deoxycholic acid, chenodeoxycholic acid, or taurocholic acid. MUC2 transcription was assayed using a MUC2 promoter reporter luciferase construct and MUC2 protein was assayed by Western blot analysis. Transcription Nuclear factor-κB activity was measured using a Nuclear factor-κB reporter construct and confirmed by Western blot analysis for Nuclear factor-κB p65. Results MUC2 transcription and MUC2 protein expression were increased four to five fold by bile acids in a time and dose-dependent manner with no effect on cell viability. Nuclear factor-κB activity was also increased. Treatment with the putative chemopreventive agent aspirin, which decreased Nuclear factor-κB activity, also decreased MUC2 transcription. Nuclear factor-κB p65 siRNA decreased MUC2 transcription, confirming the significance of Nuclear factor-κB in MUC2 induction by deoxycholic acid. Calphostin C, a specific inhibitor of protein kinase C (PKC), greatly decreased bile acid induced MUC2 transcription and Nuclear factor-κB activity, whereas inhibitors of MAP kinase had no effect. Conclusion Deoxycholic acid induced MUC2 overexpression in human esophageal adenocarcinoma cells by activation of Nuclear factor-κB transcription through a process involving PKC-dependent but not PKA, independent of activation of MAP kinase. PMID:19014523

  11. Cryptococcus neoformans Infection in Mice Lacking Type I Interferon Signaling Leads to Increased Fungal Clearance and IL-4-Dependent Mucin Production in the Lungs

    PubMed Central

    Sato, Ko; Yamamoto, Hideki; Nomura, Toshiki; Matsumoto, Ikumi; Miyasaka, Tomomitsu; Zong, Tong; Kanno, Emi; Uno, Kazuko; Ishii, Keiko; Kawakami, Kazuyoshi

    2015-01-01

    Type I interferons (IFNs) are secreted by many cell types upon stimulation via pattern recognition receptors and bind to IFN-α/β receptor (IFNAR), which is composed of IFNAR1 and IFNAR2. Although type I IFNs are well known as anti-viral cytokines, limited information is available on their role during fungal infection. In the present study, we addressed this issue by examining the effect of IFNAR1 defects on the host defense response to Cryptococcus neoformans. In IFNAR1KO mice, the number of live colonies was lower and the host immune response mediated not only by Th1 but also by Th2 and Th17-related cytokines was more accelerated in the infected lungs than in WT mice. In addition, mucin production by bronchoepithelial cells and expression of MUC5AC, a major core protein of mucin in the lungs, were significantly higher in IFNAR1KO mice than in WT mice. This increase in mucin and MUC5AC production was significantly inhibited by treatment with neutralizing anti-IL-4 mAb. In contrast, administration of recombinant IFN-αA/D significantly suppressed the production of IL-4, but not of IFN-γ and IL-17A, in the lungs of WT mice after cryptococcal infection. These results indicate that defects of IFNAR1 led to improved clearance of infection with C. neoformans and enhanced synthesis of IFN-γ and the IL-4-dependent production of mucin. They also suggest that type I IFNs may be involved in the negative regulation of early host defense to this infection. PMID:26384031

  12. Aberrant Mucin5B expression in lung adenocarcinomas detected by iTRAQ labeling quantitative proteomics and immunohistochemistry

    PubMed Central

    2013-01-01

    Background Lung cancer is the number one cause of cancer-related deaths in the United States and worldwide. The complex protein changes and/or signature of protein expression in lung cancer, particularly in non-small cell lung cancer (NSCLC) has not been well defined. Although several studies have investigated the protein profile in lung cancers, the knowledge is far from complete. Among early studies, mucin5B (MUC5B) has been suggested to play an important role in the tumor progression. MUC5B is the major gel-forming mucin in the airway. In this study, we investigated the overall protein profile and MUC5B expression in lung adenocarcinomas, the most common type of NSCLCs. Methods Lung adenocarcinoma tissue in formalin-fixed paraffin-embedded (FFPE) blocks was collected and microdissected. Peptides from 8 tumors and 8 tumor-matched normal lung tissue were extracted and labeled with 8-channel iTRAQ reagents. The labeled peptides were identified and quantified by LC-MS/MS using an LTQ Orbitrap Velos mass spectrometer. MUC5B expression identified by iTRAQ labeling was further validated using immunohistochemistry (IHC) on tumor tissue microarray (TMA). Results A total of 1288 peptides from 210 proteins were identified and quantified in tumor tissues. Twenty-two proteins showed a greater than 1.5-fold differences between tumor and tumor-matched normal lung tissues. Fifteen proteins, including MUC5B, showed significant changes in tumor tissues. The aberrant expression of MUC5B was further identified in 71.1% of lung adenocarcinomas in the TMA. Discussions A subset of tumor-associated proteins was differentially expressed in lung adenocarcinomas. The differential expression of MUC5B in lung adenocarcinomas suggests its role as a potential biomarker in the detection of adenocarcinomas. PMID:24176033

  13. Emerging Potential of Natural Products for Targeting Mucins for Therapy Against Inflammation and Cancer

    PubMed Central

    Macha, Muzafar A.; Krishn, Shiv Ram; Jahan, Rahat; Banerjee, Kasturi; Batra, Surinder K.; Jain, Maneesh

    2015-01-01

    Deregulated mucin expression is a hallmark of several inflammatory and malignant pathologies. Emerging evidence suggests that, apart from biomarkers, these deregulated mucins are functional contributors to pathogenesis in inflammation and cancer. Both overexpression and downregulation of mucins in various organ systems is associated with pathobiology of inflammation and cancer. Restoration of mucin homeostasis has become an important goal for therapy and management of such disorders and has fueled the quest for selective mucomodulators. With improved understanding of mucin regulation and mechanistic insights into their pathobiological roles, there is optimism to find selective non-toxic agents capable of modulating mucin expression and function. Recently, natural compounds derived from dietary sources have drawn attention due to their anti-inflammatory and anti-oxidant properties and low toxicity. Considerable efforts have been directed towards evaluating dietary natural products as chemopreventive and therapeutic agents; identification, characterization and synthesis of their active compounds; and improving their delivery and bioavailability. We describe the current understanding of mucin regulation, rationale for targeting mucins with natural products and discuss some natural products that modulate mucin expression and functions. We further discuss the approaches and parameters that should guide future research to identify and evaluate selective natural mucomodulators for therapy. PMID:25624117

  14. The effect of the space flight environment on mucin production in the mouse uterine tube

    NASA Astrophysics Data System (ADS)

    Svalina, Gorica; Forsman, Allan D.

    2013-06-01

    Numerous studies have indicated that the microgravity environment of space has harmful effects on several tissues throughout the body. Although this phenomenon is well documented, research in this area is still in its relative infancy. This study investigates the effects of space flight on mucin production of the uterine tubes of mice. This study examined the epithelium of the uterine tubes from female mice that were flown on the space shuttle Endeavour for 13 days in August, 2007 and their concomitant controls. The tissue was qualitatively analyzed for the type of mucin produced, i.e., acidic, neutral, acidic/neutral mixture. Further, the tissue was quantitatively analyzed for the amounts of mucins produced by measuring the thickness of the mucin layer for each region of the uterine tube: isthmus, ampulla, and infundibulum. One way ANOVA tests were used to compare mucin thickness between all three sets of animals. Results indicate similar but not identical results between the three regions of the uterine tube. The Baseline tissue had the thickest mucin layer regardless of treatment group. In the ampulla the mucin layer was the thinnest in the Flight tissue, followed by the Ground Control, with the Baseline being the thickest. Analysis of the mucin layer of the infundibulum of the three treatment groups indicated no difference in its thickness between the three regions of the uterine tube. These results indicate a trend toward thinning of the mucin layer of the uterine tube in space flight, but also indicate an influence by the housing environment.

  15. Molecular analysis of ovarian mucinous carcinoma reveals different cell of origins.

    PubMed

    Wang, Yihong; Shwartz, Lauren Ende; Anderson, Derek; Lin, Ming-Tseh; Haley, Lisa; Wu, Ren-Chin; Vang, Russell; Shih, Ie-Ming; Kurman, Robert J

    2015-09-01

    It is believed that a subset of primary ovarian mucinous tumors is derived from mature teratomas [1-5]. To confirm this, we performed microsatellite genotyping using a variety of short tandem repeat makers and analyzed allelotypes of 8 mucinous tumors (4 mucinous carcinomas, 3 atypical proliferative mucinous tumors and 1 mucinous cystadenoma) associated with a teratoma to determine whether they were clonally related. 7 of the 8 mucinous tumors showed complete or a high degree of homozygosity. Among the 6 pairs of tumors with teratoma tissue available for comparison, 5 of 6 showed a high or complete degree of allelotypes matching, which differed from the somatic allelotypes of the normal control tissue. A discrepancy was detected between carcinoma and teratoma in one pair at several loci, with different X-chromosome inactivation patterns revealed by the HUMARA clonality assay. We also investigated the allelotypes of 16 ovarian mucinous carcinomas without a teratoma in young patients (range 13-30) and in 6 older patients (range 40-67) using the same method. None of these tumors showed pure homozygosity. The number of homozygous loci in this cohort was significantly lower than that in the first. Our results suggest first, that most mucinous tumors associated with a teratoma are derived from the teratoma but occasionally they could be collision tumors and second that the majority of pure mucinous tumors in young women in whom a teratoma is not present are not derived from a teratoma. PMID:26355245

  16. Emerging potential of natural products for targeting mucins for therapy against inflammation and cancer.

    PubMed

    Macha, Muzafar A; Krishn, Shiv Ram; Jahan, Rahat; Banerjee, Kasturi; Batra, Surinder K; Jain, Maneesh

    2015-03-01

    Deregulated mucin expression is a hallmark of several inflammatory and malignant pathologies. Emerging evidence suggests that, apart from biomarkers, these deregulated mucins are functional contributors to the pathogenesis in inflammation and cancer. Both overexpression and downregulation of mucins in various organ systems is associated with pathobiology of inflammation and cancer. Restoration of mucin homeostasis has become an important goal for therapy and management of such disorders has fueled the quest for selective mucomodulators. With improved understanding of mucin regulation and mechanistic insights into their pathobiological roles, there is optimism to find selective non-toxic agents capable of modulating mucin expression and function. Recently, natural compounds derived from dietary sources have drawn attention due to their anti-inflammatory and anti-oxidant properties and low toxicity. Considerable efforts have been directed towards evaluating dietary natural products as chemopreventive and therapeutic agents; identification, characterization and synthesis of their active compounds; and improving their delivery and bioavailability. We describe the current understanding of mucin regulation, rationale for targeting mucins with natural products and discuss some natural products that modulate mucin expression and functions. We further discuss the approaches and parameters that should guide future research to identify and evaluate selective natural mucomodulators for therapy. PMID:25624117

  17. Benign mucinous metaplasia of the penis. A lesion resembling extramammary Paget's disease.

    PubMed

    Val-Bernal, J F; Hernández-Nieto, E

    2000-02-01

    Benign mucinous metaplasia in the surface epithelium of the genital area is rare and has only been reported once in the vulva. A unique case of benign mucinous metaplasia of the prepuce in a 65-year-old man is reported here. The lesion measured 0.6 cm, was located in the mucous surface of the foreskin, and showed acid mucin containing cells. We regard benign mucinous metaplasia as a reactive rather than a neoplastic process. The main lesions to be considered in the differential diagnosis are mucinous syringometaplasia, extramammary Paget's disease, cutaneous squamous cell carcinoma in situ with mucinous metaplasia, superficial spreading malignant melanoma, and epidermotropic metastasis. The confinement of mucin-containing cells to the epidermis, the absence of nuclear atypia, the basal orientation of the nuclei, the predominant location of the cells in the upper layers of the epithelium, and the fact that the mucinous cells are replacing the squamous epithelium rather that infiltrating it, all assist in recognizing mucinous metaplasia of the penis as a specific and benign entity. PMID:10678702

  18. Sensory neuropeptides and the human lower airways: present state and future directions.

    PubMed

    Joos, G F; Germonpre, P R; Kips, J C; Peleman, R A; Pauwels, R A

    1994-06-01

    The sensory neuropeptides, substance P and neurokinin A, are present in human airway nerves, beneath and within the epithelium, around blood vessels and submucosal glands, and within the bronchial smooth muscle layer. Studies on autopsy tissue, bronchoalveolar lavage and sputum suggest that in asthma the substance P content of the airways may be increased. Neurokinin A is a more potent bronchoconstrictor than substance P. Asthmatics are hyperresponsive to neurokinin A and substance P. The neuropeptide degrading enzyme, neutral endopeptidase is present in the airways and is involved in the degradation of endogenously released and exogenously administered substance P and neurokinin A, both in normal and asthmatic subjects. As for other indirect bronchoconstrictor stimuli, the effect of neurokinin A on airway calibre in asthmatics can be inhibited by pretreatment with nedocromil sodium. Evidence is accumulating, not only from studies in animals but also from experiments on human airways, that tachykinins may also cause mucus secretion and plasma extravasation. They also have important proinflammatory effects, such as the chemoattraction of eosinophils and neutrophils, the adhesion of neutrophils, and the stimulation of lymphocytes, macrophages and mast cells. The tachykinins interact with the targets on the airways by specific tachykinin receptors. The NK1 and the NK2 receptor have been characterized in human airways, both pharmacologically and by cloning. The NK2 receptor is responsible for the in vitro contraction of normal airways, whilst the NK1 receptor is responsible for most of the other airway effects. Because of their presence in the airways and because of their ability to mimic the various pathophysiological features of asthma, substance P and neurokinin A are presently considered as possible mediators of asthma. The present development of potent and selective tachykinin antagonists will allow us to further define the role of tachykinins in the pathogenesis

  19. Glandular Proteome Identifies Antiprotease Cystatin C as a Critical Modulator of Airway Hydration and Clearance.

    PubMed

    Evans, T Idil Apak; Joo, Nam Soo; Keiser, Nicholas W; Yan, Ziying; Tyler, Scott R; Xie, Weiliang; Zhang, Yulong; Hsiao, Jordy J; Cho, Hyung-Ju; Wright, Michael E; Wine, Jeffrey J; Engelhardt, John F

    2016-04-01

    Defects in the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel lead to viscous secretions from submucosal glands that cannot be properly hydrated and cleared by beating cilia in cystic fibrosis (CF) airways. The mechanisms by which CFTR, and the predominant epithelial sodium channel (ENaC), control the hydration and clearance of glandular secretions remain unclear. We used a proteomics approach to characterize the proteins contained in CF and non-CF submucosal gland fluid droplets and found that differentially regulated proteases (cathepsin S and H) and their antiprotease (cystatin C) influenced the equilibration of fluid on the airway surface and tracheal mucociliary clearance (MCC). Contrary to prevailing models of airway hydration and clearance, cystatin C, or raising the airway surface liquid (ASL) pH, inhibited cathepsin-dependent ENaC-mediated fluid absorption and raised the height of ASL, and yet decreased MCC velocity. Importantly, coupling of both CFTR and ENaC activities were required for effective MCC and for effective ASL height equilibration after volume challenge. Cystatin C-inhibitable cathepsins controlled initial phases of ENaC-mediated fluid absorption, whereas CFTR activity was required to prevent ASL dehydration. Interestingly, CF airway epithelia absorbed fluid more slowly owing to reduced cysteine protease activity in the ASL but became abnormally dehydrated with time. Our findings demonstrate that, after volume challenge, pH-dependent protease-mediated coupling of CFTR and ENaC activities are required for rapid fluid equilibration at the airway surface and for effective MCC. These findings provide new insights into how glandular fluid secretions may be equilibrated at the airway surface and how this process may be impaired in CF. PMID:26334941

  20. Autophagy plays an essential role in cigarette smoke-induced expression of MUC5AC in airway epithelium.

    PubMed

    Zhou, Jie-Sen; Zhao, Yun; Zhou, Hong-Bin; Wang, Yong; Wu, Yin-Fang; Li, Zhou-Yang; Xuan, Nan-Xia; Zhang, Chao; Hua, Wen; Ying, Song-Min; Li, Wen; Shen, Hua-Hao; Chen, Zhi-Hua

    2016-06-01

    Mucus hypersecretion is a common pathological feature of chronic airway inflammatory diseases including chronic obstructive pulmonary disease (COPD). However, the molecular basis for this condition remains incompletely understood. We have previously demonstrated a critical role of autophagy in COPD pathogenesis through mediating apoptosis of lung epithelial cells. In this study, we aimed to investigate the function of autophagy as well as its upstream and downstream signals in cigarette smoke-induced mucus production in human bronchial epithelial (HBE) cells and in mouse airways. Cigarette smoke extract (CSE), as well as the classical autophagy inducers starvation or Torin-1, significantly triggered MUC5AC expression, and inhibition of autophagy markedly attenuated CSE-induced mucus production. The CSE-induced autophagy was mediated by mitochondrial reactive oxygen species (mitoROS), which regulated mucin expression through the JNK and activator protein-1 pathway. Epidermal growth factor receptor (EGFR) was also required for CSE-induced MUC5AC in HBE cells, but it exerted inconsiderable effects on the autophagy-JNK signaling cascade. Airways of mice with dysfunctional autophagy-related genes displayed a markedly reduced number of goblet cells and attenuated levels of Muc5ac in response to cigarette smoke exposure. These results altogether suggest that mitoROS-dependent autophagy is essential for cigarette smoke-induced mucus hyperproduction in airway epithelial cells, and reemphasize autophagy inhibition as a novel therapeutic strategy for chronic airway diseases. PMID:27036871

  1. Chloride and potassium channels in cystic fibrosis airway epithelia

    NASA Astrophysics Data System (ADS)

    Welsh, Michael J.; Liedtke, Carole M.

    1986-07-01

    Cystic fibrosis, the most common lethal genetic disease in Caucasians, is characterized by a decreased permeability in sweat gland duct and airway epithelia. In sweat duct epithelium, a decreased Cl- permeability accounts for the abnormally increased salt content of sweat1. In airway epithelia a decreased Cl- permeability, and possibly increased sodium absorption, may account for the abnormal respiratory tract fluid2,3. The Cl- impermeability has been localized to the apical membrane of cystic fibrosis airway epithelial cells4. The finding that hormonally regulated Cl- channels make the apical membrane Cl- permeable in normal airway epithelial cells5 suggested abnormal Cl- channel function in cystic fibrosis. Here we report that excised, cell-free patches of membrane from cystic fibrosis epithelial cells contain Cl- channels that have the same conductive properties as Cl- channels from normal cells. However, Cl- channels from cystic fibrosis cells did not open when they were attached to the cell. These findings suggest defective regulation of Cl- channels in cystic fibrosis epithelia; to begin to address this issue, we performed two studies. First, we found that isoprenaline, which stimulates Cl- secretion, increases cellular levels of cyclic AMP in a similar manner in cystic fibrosis and non-cystic fibrosis epithelial cells. Second, we show that adrenergic agonists open calcium-activated potassium channels, indirectly suggesting that calcium-dependent stimulus-response coupling is intact in cystic fibrosis. These data suggest defective regulation of Cl- channels at a site distal to cAMP accumulation.

  2. A novel dissociative steroid VBP15 reduces MUC5AC gene expression in airway epithelial cells but lacks the GRE mediated transcriptional properties of dexamethasone.

    PubMed

    Garvin, Lindsay M; Chen, Yajun; Damsker, Jesse M; Rose, Mary C

    2016-06-01

    Overproduction of secretory mucins contributes to morbidity/mortality in inflammatory lung diseases. Inflammatory mediators directly increase expression of mucin genes, but few drugs have been shown to directly repress mucin gene expression. IL-1β upregulates the MUC5AC mucin gene in part via the transcription factors NFκB while the glucocorticoid Dexamethasone (Dex) transcriptionally represses MUC5AC expression by Dex-activated GR binding to two GRE cis-sites in the MUC5AC promoter in lung epithelial cells. VBP compounds (ReveraGen BioPharma) maintain anti-inflammatory activity through inhibition of NFκB but exhibit reduced GRE-mediated transcriptional properties associated with adverse side-effects and thus have potential to minimize harmful side effects of long-term steroid therapy in inflammatory lung diseases. We investigated VBP15 efficacy as an anti-mucin agent in two types of airway epithelial cells and analyzed the transcription factor activity and promoter binding associated with VBP15-induced MUC5AC repression. VBP15 reduced MUC5AC mRNA abundance in a dose- and time-dependent manner similar to Dex in the presence or absence of IL-1β in A549 and differentiated human bronchial epithelial cells. Repression was abrogated in the presence of RU486, demonstrating a requirement for GR in the VBP15-induced repression of MUC5AC. Inhibition of NFκB activity resulted in reduced baseline expression of MUC5AC indicating that constitutive activity maintains MUC5AC production. Chromatin immunoprecipitation analysis demonstrated lack of GR and of p65 (NFκB) binding to composite GRE domains in the MUC5AC promoter following VBP15 exposure of cells, in contrast to Dex. These data demonstrate that VBP15 is a novel anti-mucin agent that mediates the reduction of MUC5AC gene expression differently than the classical glucocorticoid, Dex. PMID:27133900

  3. Efficacy of a novel mucolytic agent on pseudomyxoma peritonei mucin, with potential for treatment through peritoneal catheters.

    PubMed

    Akhter, Javed; Pillai, Krishna; Chua, Terence C; Alzarin, Naeef; Morris, David Lawson

    2014-01-01

    Compared to current treatment for pseudomyxoma peritonei (PMP), the extraction of solubilised mucin through peritoneal catheter can be minimally invasive. However, mucin has variable appearance that may influence mucolysis. Hence, we investigated the mucolysis of 36 mucin samples with a novel agent. Using visual inspection and hardness index, PMP mucin was classified into three grades. The mucin pathological category was identified from patient record. Subsequently, the dissolution of the samples was tested. For in vitro, 1 g of mucin was treated to the mucolytic agent in 10 ml TRIS buffer at 37 deg. Celsius for 3 hours, with weighing of residual mucin. Control treatment was similar but received TRIS buffer. For in vivo, 2 g of implanted intra-peritoneal mucin in nude rats was treated to mucolytic (2 X 500 ul/24 hr, over 48 hours, plus another treatment before sacrifice at 56 hours, with weighing of residual mucin. Controls were treated but only with TRIS buffer. Six animals were used for each mucin grade (3 mucolytic treated & and 3 controls). Grades of mucin were soft mucin (62%), semi hard (20%) and hard mucin (18%). Diffuse peritoneal adenomucinosis had 50% of soft mucin and peritoneal mucinous carcinoma had 11% (P = 0.0382). In vitro and in vivo absolute disintegration was 100% for soft, 57.38% and 48.67% for semi hard, 50% and 28.67% for hard mucin. Majority of mucin were soft with complete disintegration, the rest showed variable disintegration, suggesting that the mucolytic has potential for treating PMP. PMID:25232491

  4. Efficacy of a novel mucolytic agent on pseudomyxoma peritonei mucin, with potential for treatment through peritoneal catheters

    PubMed Central

    Akhter, Javed; Pillai, Krishna; Chua, Terence C; Alzarin, Naeef; Morris, David Lawson

    2014-01-01

    Compared to current treatment for pseudomyxoma peritonei (PMP), the extraction of solubilised mucin through peritoneal catheter can be minimally invasive. However, mucin has variable appearance that may influence mucolysis. Hence, we investigated the mucolysis of 36 mucin samples with a novel agent. Using visual inspection and hardness index, PMP mucin was classified into three grades. The mucin pathological category was identified from patient record. Subsequently, the dissolution of the samples was tested. For in vitro, 1 g of mucin was treated to the mucolytic agent in 10 ml TRIS buffer at 37 deg. Celsius for 3 hours, with weighing of residual mucin. Control treatment was similar but received TRIS buffer. For in vivo, 2 g of implanted intra-peritoneal mucin in nude rats was treated to mucolytic (2 X 500 ul/24 hr, over 48 hours, plus another treatment before sacrifice at 56 hours, with weighing of residual mucin. Controls were treated but only with TRIS buffer. Six animals were used for each mucin grade (3 mucolytic treated & and 3 controls). Grades of mucin were soft mucin (62%), semi hard (20%) and hard mucin (18%). Diffuse peritoneal adenomucinosis had 50% of soft mucin and peritoneal mucinous carcinoma had 11% (P = 0.0382). In vitro and in vivo absolute disintegration was 100% for soft, 57.38% and 48.67% for semi hard, 50% and 28.67% for hard mucin. Majority of mucin were soft with complete disintegration, the rest showed variable disintegration, suggesting that the mucolytic has potential for treating PMP. PMID:25232491

  5. PAX2, PAX8 and CDX2 Expression in Metastatic Mucinous, Primary Ovarian Mucinous and Seromucinous Tumors and Review of the Literature.

    PubMed

    Ates Ozdemir, D; Usubutun, A

    2016-07-01

    Ovarian cancer is the most common cause of gynecologic cancer death. Both morphologically and immunohistochemically, metastatic mucinous tumors are the best mimickers of mucinous ovarian tumors; its pathogenesis still remains a mystery. PAX2 and PAX8 immunohisyochemistries are useful for differentiating numerous primary tumour types from metastatic ones. There are few studies in literature about PAX expressions in mucinous and seromucinous tumors. None of these are takes into account the histologic type (whether it is seromucinous or mucinous) or the metastatic origin. With this purpose hematoxylin and eosine slides of ovarian mucinous and seromucinous tumors were re-evaluated and one block was chosen for each case. The study included 76 ovarian mucinous and seromucinous tumors of the ovary reported in Hacettepe University department of pathology between 2000 and 2013. Tissue microarray (TMA) was designed from the chosen blocks, PAX2, PAX8, CDX2 immunostains was preformed to the TMA slides. As a result, most of the metastatic cases were negative for PAX2 (91.2 %) and PAX8 (86.3 %), many were diffusely and strongly positive for CDX2 (68.2 %). Seromucinous tumors were devoid of CDX2 expression; but all cases (except one) displayed strong and diffuse positivity with PAX8. In other words differing from mucinous tumors, seromucinous tumors show strong PAX8 positivity-similar to serous tumors. This study shows that PAX8 and CDX2 could be useful in differentiating primary mucinous from metastatic tumor. Furthermore unlike the homogeneity in seromucinous tumors for PAX8 and CDX2 mucinous tumors shows heterogeneity with different expression patterns. PMID:26797858

  6. Excessive Dynamic Airway Collapse: An Unexpected Contributor to Respiratory Failure in a Surgical Patient.

    PubMed

    Lyaker, Michael R; Davila, Victor R; Papadimos, Thomas J

    2015-01-01

    Central airway collapse plays a significant, underrecognized role in respiratory failure after extubation of critically ill patients. Historically, airway collapse has been attributed to tracheomalacia (TM), softening of the cartilage in the trachea and other large airways. More recently, excessive dynamic airway collapse (EDAC) has been described as a distinct process unrelated to a loss of cartilaginous airway support. EDAC is caused by the posterior wall of the trachea bulging forward and causing airway obstruction during exhalation. This process is exaggerated when intrathoracic pressure is increased and results in a clinical picture of coughing, difficulty clearing secretions, dyspnea, and stridor. The increased use of computerized tomography and fiberoptic bronchoscopy has identified varying degrees of EDAC and TM in both symptomatic and asymptomatic individuals. This has led to renewed consideration of airway collapse and the different processes that contribute to it. Here we describe a 43-year-old morbidly obese patient who failed repeated attempts at extubation after elective hysterectomy. We will discuss the processes of EDAC and TM, describe how this condition contributed to this patient's respiratory failure, and review diagnosis and management options. PMID:26167306

  7. Excessive Dynamic Airway Collapse: An Unexpected Contributor to Respiratory Failure in a Surgical Patient

    PubMed Central

    Lyaker, Michael R.; Davila, Victor R.; Papadimos, Thomas J.

    2015-01-01

    Central airway collapse plays a significant, underrecognized role in respiratory failure after extubation of critically ill patients. Historically, airway collapse has been attributed to tracheomalacia (TM), softening of the cartilage in the trachea and other large airways. More recently, excessive dynamic airway collapse (EDAC) has been described as a distinct process unrelated to a loss of cartilaginous airway support. EDAC is caused by the posterior wall of the trachea bulging forward and causing airway obstruction during exhalation. This process is exaggerated when intrathoracic pressure is increased and results in a clinical picture of coughing, difficulty clearing secretions, dyspnea, and stridor. The increased use of computerized tomography and fiberoptic bronchoscopy has identified varying degrees of EDAC and TM in both symptomatic and asymptomatic individuals. This has led to renewed consideration of airway collapse and the different processes that contribute to it. Here we describe a 43-year-old morbidly obese patient who failed repeated attempts at extubation after elective hysterectomy. We will discuss the processes of EDAC and TM, describe how this condition contributed to this patient's respiratory failure, and review diagnosis and management options. PMID:26167306

  8. Putting the Squeeze on Airway Epithelia.

    PubMed

    Park, Jin-Ah; Fredberg, Jeffrey J; Drazen, Jeffrey M

    2015-07-01

    Asthma is characterized by chronic inflammation, airway hyperresponsiveness, and progressive airway remodeling. The airway epithelium is known to play a critical role in the initiation and perpetuation of these processes. Here, we review how excessive epithelial stress generated by bronchoconstriction is sufficient to induce airway remodeling, even in the absence of inflammatory cells. PMID:26136543

  9. Putting the Squeeze on Airway Epithelia

    PubMed Central

    Park, Jin-Ah; Fredberg, Jeffrey J.

    2015-01-01

    Asthma is characterized by chronic inflammation, airway hyperresponsiveness, and progressive airway remodeling. The airway epithelium is known to play a critical role in the initiation and perpetuation of these processes. Here, we review how excessive epithelial stress generated by bronchoconstriction is sufficient to induce airway remodeling, even in the absence of inflammatory cells. PMID:26136543

  10. Facilitation of Allergic Sensitization and Allergic Airway Inflammation by Pollen-Induced Innate Neutrophil Recruitment.

    PubMed

    Hosoki, Koa; Aguilera-Aguirre, Leopoldo; Brasier, Allan R; Kurosky, Alexander; Boldogh, Istvan; Sur, Sanjiv

    2016-01-01

    Neutrophil recruitment is a hallmark of rapid innate immune responses. Exposure of airways of naive mice to pollens rapidly induces neutrophil recruitment. The innate mechanisms that regulate pollen-induced neutrophil recruitment and the contribution of this neutrophilic response to subsequent induction of allergic sensitization and inflammation need to be elucidated. Here we show that ragweed pollen extract (RWPE) challenge in naive mice induces C-X-C motif ligand (CXCL) chemokine synthesis, which stimulates chemokine (C-X-C motif) receptor 2 (CXCR2)-dependent recruitment of neutrophils into the airways. Deletion of Toll-like receptor 4 (TLR4) abolishes CXCL chemokine secretion and neutrophil recruitment induced by a single RWPE challenge and inhibits induction of allergic sensitization and airway inflammation after repeated exposures to RWPE. Forced induction of CXCL chemokine secretion and neutrophil recruitment in mice lacking TLR4 also reconstitutes the ability of multiple challenges of RWPE to induce allergic airway inflammation. Blocking RWPE-induced neutrophil recruitment in wild-type mice by administration of a CXCR2 inhibitor inhibits the ability of repeated exposures to RWPE to stimulate allergic sensitization and airway inflammation. Administration of neutrophils derived from naive donor mice into the airways of Tlr4 knockout recipient mice after each repeated RWPE challenge reconstitutes allergic sensitization and inflammation in these mice. Together these observations indicate that pollen-induced recruitment of neutrophils is TLR4 and CXCR2 dependent and that recruitment of neutrophils is a critical rate-limiting event that stimulates induction of allergic sensitization and airway inflammation. Inhibiting pollen-induced recruitment of neutrophils, such as by administration of CXCR2 antagonists, may be a novel strategy to prevent initiation of pollen-induced allergic airway inflammation. PMID:26086549

  11. Airway clearance in neuromuscular weakness.

    PubMed

    Gauld, Leanne Maree

    2009-05-01

    Impaired airway clearance leads to recurrent chest infections and respiratory deterioration in neuromuscular weakness. It is frequently the cause of death. Cough is the major mechanism of airway clearance. Cough has several components, and assessment tools are available to measure the different components of cough. These include measuring peak cough flow, respiratory muscle strength, and inspiratory capacity. Each is useful in assessing the ability to generate an effective cough, and can be used to guide when techniques of assisting airway clearance may be effective for the individual and which are most effective. Techniques to assist airway clearance include augmenting inspiration by air stacking, augmenting expiration by assisting the cough, and augmenting both inspiration and expiration with the mechanical insufflator-exsufflator or by direct suctioning via a tracheostomy. Physiotherapists are invaluable in assisting airway clearance, and in teaching patients and their families how to use these techniques. Use of the mechanical insufflator-exsufflator has gained popularity in recent times, but several simpler, more economical methods are available to assist airway clearance that can be used effectively alone or in combination. This review examines the literature available on the assessment and management of impaired airway clearance in neuromuscular weakness. PMID:19379290

  12. Irritant-induced airway disorders.

    PubMed

    Brooks, Stuart M; Bernstein, I Leonard

    2011-11-01

    Thousands of persons experience accidental high-level irritant exposures each year but most recover and few die. Irritants function differently than allergens because their actions proceed nonspecifically and by nonimmunologic mechanisms. For some individuals, the consequence of a single massive exposure to an irritant, gas, vapor or fume is persistent airway hyperresponsiveness and the clinical picture of asthma, referred to as reactive airways dysfunction syndrome (RADS). Repeated irritant exposures may lead to chronic cough and continual airway hyperresponsiveness. Cases of asthma attributed to repeated irritant-exposures may be the result of genetic and/or host factors. PMID:21978855

  13. Liquid Movement Across the Surface Epithelium of Large Airways

    PubMed Central

    Chambers, Lucy A.; Rollins, Brett M.; Tarran, Robert

    2009-01-01

    The cystic fibrosis conductance regulator CFTR gene is found on chromosome 7 (Kerem et al., 1989; Riordan et al., 1989) and encodes for a 1,480 amino acid protein which is present in the plasma membrane of epithelial cells (Anderson et al., 1992). This protein appears to have many functions, but a unifying theme is that it acts as a protein kinase C- and cyclic AMP-regulated Cl- channel (Winpenny et al., 1995; Jia et al., 1997). In the superficial epithelium of the conducting airways, CFTR is involved in Cl- secretion (Boucher, 2003) and also acts as a regulator of the epithelial Na+ channel (ENaC) and hence Na+ absorption (Boucher et al., 1986; Stutts et al., 1995). In this chapter, we will discuss the regulation of these two ion channels, and how they can influence liquid movement across the superficial airway epithelium. PMID:17692578

  14. Increased airway glucose increases airway bacterial load in hyperglycaemia

    PubMed Central

    Gill, Simren K.; Hui, Kailyn; Farne, Hugo; Garnett, James P.; Baines, Deborah L.; Moore, Luke S.P.; Holmes, Alison H.; Filloux, Alain; Tregoning, John S.

    2016-01-01

    Diabetes is associated with increased frequency of hospitalization due to bacterial lung infection. We hypothesize that increased airway glucose caused by hyperglycaemia leads to increased bacterial loads. In critical care patients, we observed that respiratory tract bacterial colonisation is significantly more likely when blood glucose is high. We engineered mutants in genes affecting glucose uptake and metabolism (oprB, gltK, gtrS and glk) in Pseudomonas aeruginosa, strain PAO1. These mutants displayed attenuated growth in minimal medium supplemented with glucose as the sole carbon source. The effect of glucose on growth in vivo was tested using streptozocin-induced, hyperglycaemic mice, which have significantly greater airway glucose. Bacterial burden in hyperglycaemic animals was greater than control animals when infected with wild type but not mutant PAO1. Metformin pre-treatment of hyperglycaemic animals reduced both airway glucose and bacterial load. These data support airway glucose as a critical determinant of increased bacterial load during diabetes. PMID:27273266

  15. Increased airway glucose increases airway bacterial load in hyperglycaemia.

    PubMed

    Gill, Simren K; Hui, Kailyn; Farne, Hugo; Garnett, James P; Baines, Deborah L; Moore, Luke S P; Holmes, Alison H; Filloux, Alain; Tregoning, John S

    2016-01-01

    Diabetes is associated with increased frequency of hospitalization due to bacterial lung infection. We hypothesize that increased airway glucose caused by hyperglycaemia leads to increased bacterial loads. In critical care patients, we observed that respiratory tract bacterial colonisation is significantly more likely when blood glucose is high. We engineered mutants in genes affecting glucose uptake and metabolism (oprB, gltK, gtrS and glk) in Pseudomonas aeruginosa, strain PAO1. These mutants displayed attenuated growth in minimal medium supplemented with glucose as the sole carbon source. The effect of glucose on growth in vivo was tested using streptozocin-induced, hyperglycaemic mice, which have significantly greater airway glucose. Bacterial burden in hyperglycaemic animals was greater than control animals when infected with wild type but not mutant PAO1. Metformin pre-treatment of hyperglycaemic animals reduced both airway glucose and bacterial load. These data support airway glucose as a critical determinant of increased bacterial load during diabetes. PMID:27273266

  16. Rare Upper Airway Anomalies.

    PubMed

    Windsor, Alanna; Clemmens, Clarice; Jacobs, Ian N

    2016-01-01

    A broad spectrum of congenital upper airway anomalies can occur as a result of errors during embryologic development. In this review, we will describe the clinical presentation, diagnosis, and management strategies for a few select, rare congenital malformations of this system. The diagnostic tools used in workup of these disorders range from prenatal tests to radiological imaging, swallowing evaluations, indirect or direct laryngoscopy, and rigid bronchoscopy. While these congenital defects can occur in isolation, they are often associated with disorders of other organ systems or may present as part of a syndrome. Therefore workup and treatment planning for patients with these disorders often involves a team of multiple specialists, including paediatricians, otolaryngologists, pulmonologists, speech pathologists, gastroenterologists, and geneticists. PMID:26277452

  17. [Reactive airways dysfunction syndrome].

    PubMed

    Costa, R; Orriols, R

    2005-01-01

    Reactive airways dysfunction syndrome, better known as RADS, was described as a clinical entity consisting in the appearance of bronchial asthma due to massive toxic inhalation. The term was coined and recognised for the first time in 1985. Since then different publications have verified new cases as well as different causal agents. It usually arises from an accident at the work place and in closed or poorly ventilated spaces, where high concentrations of irritant products are inhaled in the form of gas, smoke or vapour. In the following minutes or hours symptoms of bronchial obstruction appear in an acute form, with bronchial hyperresponsiveness persisting for months or years. The affected patients do not show a recurrence of symptoms following exposure to non-toxic doses of the same agent that started the symptoms. This is why diagnosis is based on clinical manifestations as it is not reproducible through a provocation test. PMID:15915173

  18. Histochemical and structural analysis of mucous glycoprotein secreted by the gill of Mytilus edulis

    SciTech Connect

    Ahn, Hae-Young.

    1988-01-01

    Studies were carried out to characterized various mucous cells in the gill filament, to ascertain structural characteristics of the secreted mucous glycoproteins, and to determine the ability of the gill epithelium to incorporate ({sup 14}C)glucosamine as a precursor in the biosynthesis and secretion of mucous glycoproteins. Using histochemical staining techniques, mucous cells containing neutral and acidic mucins were found in the lateral region, whereas mucous cells containing primarily neutral or sulfated mucins were found in the postlateral region. Serotonin, but not dopamine, stimulated the mucous secretion. In tissues pretreated with ({sup 14}C)glucosamine, the secreted glycoproteins contain incorporated radiolabel. Analysis by column chromatography using Bio-Gel P-2 and P-6 shows that the secretion contains two glycoprotein populations. Glycoprotein II has a molecular weight of 2.3 {times} 10{sup 4} daltons. Upon alkaline reductive borohydride cleavage of the O-glycosidic linkages of glycoprotein I, about 70% of the radiolabel was removed from the protein. Gas chromatographic analysis of the carbohydrate composition shows that the glycoproteins contains N-acetylglucosamine (GluNAc), N-acetylgalactosamine (GalNAc), and galactose, fucose and mannose. Amino acid analysis shows that the glycoproteins are rich in serine, threonine and proline.

  19. A standardized aqueous extract of Anoectochilus formosanus modulated airway hyperresponsiveness in an OVA-inhaled murine model.

    PubMed

    Hsieh, C-C; Hsiao, H-B; Lin, W-C

    2010-07-01

    Anoectochilus formosanus HAYATA, a Chinese herb, is a valued folk medicine for fever, pain, and diseases of the lung and liver. Allergic asthma is characterized by increased serum IgE level and inflammation of the airways with high levels of interleukin (IL)-4 and IL-5 in bronchoalveolar lavage fluids (BALF). Constriction of airway smooth muscle and development of airway hyperresponsiveness (AHR) are the most important symptoms of allergic asthma. In our previous study, a standardized aqueous extract of A. formosanus (SAEAF) was used to modulate innate immunity of normal mice. In this study, airway inflammatory infiltrations, including T cell differentiation, cytokine modulation, allergic antibodies estimation, pulmonary pathology, and enhanced pause (Penh) of AHR were used to evaluate SAEAF treatment of an ovalbumin (OVA)-inhaled airway allergic murine model. The resulting cytokine profiles demonstrated that SAEAF can significantly reduce Th2 polarization after administration of SAEAF in OVA inhalation. These results also suggest that SAEAF modulates cytokine secretion in allergic asthma. Modulated natural T regulatory cells (CD25+/CD4+, Treg) were also shown to increase immuno-suppression in the allergic lung inflammation and further down-regulate airway inflammatory infiltration in eosinophils and macrophages. Finally, decreased airway anti-OVA IgE secretion and reduced AHR were observed. Our results indicate that the administration of SAEAF can modulate cytokines and T cell subpopulation by regulating inflammatory cell infiltration and modulating the allergic response. PMID:20092984

  20. Basal nucleotide levels, release, and metabolism in normal and cystic fibrosis airways.

    PubMed Central

    Donaldson, S. H.; Lazarowski, E. R.; Picher, M.; Knowles, M. R.; Stutts, M. J.; Boucher, R. C.

    2000-01-01

    BACKGROUND: Cystic fibrosis (CF) is a syndrome caused by mutations in the cystic fibrosis transmembrane regulator (CFTR) gene. Despite advances in our understanding of the molecular pathogenesis of CF, the link between CFTR gene mutations and the pathogenesis of CF lung disease remains poorly defined. CFTR has been assigned a number of putative functions that may contribute to innate airway defense, including the regulation of adenosine 5'-triphosphate (ATP) release into the extracellular environment. Because extracellular ATP and uridine 5'-triphosphate (UTP) may regulate airway mucociliary clearance via interaction with luminal P2Y2 receptors, the loss of CFTR-mediated nucleotide release could explain the defect in CF airway defense. MATERIALS AND METHODS: We tested the physiologic importance of CFTR-mediated nucleotide release in vivo by directly measuring levels of ATP and UTP in nasal airway surface liquid from normal and CF subjects. Because these basal nucleotide levels reflect the net activities of nucleotide release and metabolic pathways, we also measured constitutive rates of nucleotide release and metabolism on well-differentiated normal and CF airway cultures in vitro. The measurement of ATP release rates were paralleled by in vivo studies employing continuous nasal perfusion in normal and CF subjects. Finally, the regulation of ATP release by isoproterenol and methacholine-stimulated submucosal gland secretion was tested. RESULTS: These studies revealed that steady-state ATP and UTP levels were similar in normal (470 +/- 131 nM and 37 +/- 7 nM, respectively) and CF (911 +/- 199 nM and 33 +/- 12 nM, respectively) subjects. The rates of both ATP release and metabolism were also similar in normal and CF airway epithelia both in vitro and in vivo. Airway submucosal glands did not secrete nucleotides, but rather, secreted a soluble nucleotidase in response to cholinergic stimuli. CONCLUSION: The concentration of ATP in airway surface liquid is in a range

  1. HER2 drives Mucin-like 1 to control proliferation in breast cancer cells

    PubMed Central

    Conley, S J; Bosco, E E; Tice, D A; Hollingsworth, R E; Herbst, R; Xiao, Z

    2016-01-01

    Mucin-like 1 (MUCL1) was first identified as a breast-specific gene over a decade ago. Based on its highly restricted mRNA expression in breast tissue and continued expression during breast tumorigenesis and progression, MUCL1 is an attractive tumor-associated antigen and a potential therapeutic target. However, very little is known about the cellular location, biological functions and regulation of the MUCL1 protein, which will have a major impact on its druggability. Here we describe our efforts to fully characterize the cellular localization of MUCL1, investigate its regulation by key breast cancer oncogenes such as human epidermal growth factor receptor 2 (HER2) and discover its functional roles in breast cancer. Although some mucins are membrane bound, our data indicate that MUCL1 is secreted by some breast cancer cells, whereas others only express high levels of intracellular MUCL1. MUCL1 expression is highest in HER2-amplified breast tumors and inhibiting HER2 activity in tumor cells resulted in a decreased MUCL1 expression. In-depth investigation demonstrated that phosphoinositide3-kinase/Akt pathway, but not Ras/MEK pathway, controls MUCL1 expression downstream of HER2. Phenotypic assays revealed a strong dependence of HER2-positive cells on MUCL1 for cell proliferation. We further identified the mechanism by which MUCL1 regulates cell growth. Knockdown of MUCL1 induced a G1/S phase arrest concomitant with decreased cyclin D and increased p21 and p27 levels. Finally, we investigated the impact of MUCL1 loss on kinase signaling pathways in breast cancer cells through phospho-kinase array profiling. MUCL1 silencing abrogated phospho-focal adhesion kinase (FAK), Jun NH2-terminal kinase (JNK) and c-Jun signals, but not extracellular signal-regulated kinase or Akt pathway activities, thereby pointing to FAK/JNK pathway as the downstream effector of MUCL1 signaling. We are the first to identify an important role for MUCL1 in the proliferation of breast cancer

  2. HER2 drives Mucin-like 1 to control proliferation in breast cancer cells.

    PubMed

    Conley, S J; Bosco, E E; Tice, D A; Hollingsworth, R E; Herbst, R; Xiao, Z

    2016-08-11

    Mucin-like 1 (MUCL1) was first identified as a breast-specific gene over a decade ago. Based on its highly restricted mRNA expression in breast tissue and continued expression during breast tumorigenesis and progression, MUCL1 is an attractive tumor-associated antigen and a potential therapeutic target. However, very little is known about the cellular location, biological functions and regulation of the MUCL1 protein, which will have a major impact on its druggability. Here we describe our efforts to fully characterize the cellular localization of MUCL1, investigate its regulation by key breast cancer oncogenes such as human epidermal growth factor receptor 2 (HER2) and discover its functional roles in breast cancer. Although some mucins are membrane bound, our data indicate that MUCL1 is secreted by some breast cancer cells, whereas others only express high levels of intracellular MUCL1. MUCL1 expression is highest in HER2-amplified breast tumors and inhibiting HER2 activity in tumor cells resulted in a decreased MUCL1 expression. In-depth investigation demonstrated that phosphoinositide3-kinase/Akt pathway, but not Ras/MEK pathway, controls MUCL1 expression downstream of HER2. Phenotypic assays revealed a strong dependence of HER2-positive cells on MUCL1 for cell proliferation. We further identified the mechanism by which MUCL1 regulates cell growth. Knockdown of MUCL1 induced a G1/S phase arrest concomitant with decreased cyclin D and increased p21 and p27 levels. Finally, we investigated the impact of MUCL1 loss on kinase signaling pathways in breast cancer cells through phospho-kinase array profiling. MUCL1 silencing abrogated phospho-focal adhesion kinase (FAK), Jun NH2-terminal kinase (JNK) and c-Jun signals, but not extracellular signal-regulated kinase or Akt pathway activities, thereby pointing to FAK/JNK pathway as the downstream effector of MUCL1 signaling. We are the first to identify an important role for MUCL1 in the proliferation of breast cancer

  3. Novel bifidobacterial glycosidases acting on sugar chains of mucin glycoproteins.

    PubMed

    Katayama, Takane; Fujita, Kiyotaka; Yamamoto, Kenji

    2005-05-01

    Bifidobacterium bifidum was found to produce a specific 1,2-alpha-L-fucosidase. Its gene (afc A) has been cloned and the DNA sequence was determined. The Afc A protein consisting of 1959 amino acid residues with a predicted molecular mass of 205 kDa can be divided into three domains; the N-terminal function-unknown domain (576 aa), the catalytic domain (898 aa), and the C-terminal bacterial Ig-like domain (485 aa). The recombinant catalytic domain specifically hydrolyzed the terminal alpha-(1-->2)-fucosidic linkages of various oligosaccharides and sugar chains of glycoproteins. The primary structure of the catalytic domain exhibited no similarity to those of any glycoside hydrolases but showed similarity to those of several hypothetical proteins in a database, which resulted in establishment of a novel glycoside hydrolase family (GH family 95). Several bifidobacteria were found to produce a specific endo-alpha-N-acetylgalactosaminidase, which is the endoglycosidase liberating the O-glycosidically linked galactosyl beta1-->3 N-acetylgalactosamine disaccharide from mucin glycoprotein. The molecular cloning of endo-alpha-N-acetylgalactosaminidase was carried out on Bifidobacterium longum based on the information in the database. The gene was found to comprise 1966 amino acid residues with a predicted molecular mass of 210 kDa. The recombinant protein released galactosyl beta1-->3 N-acetylgalactosamine disaccharide from natural glycoproteins. This enzyme of B. longum is believed to be involved in the catabolism of oligosaccharide of intestinal mucin glycoproteins. Both 1,2-alpha-L-fucosidase and endo-alpha-N-acetylgalactosaminidase are novel and specific enzymes acting on oligosaccharides that exist mainly in mucin glycoproteins. Thus, it is reasonable to conclude that bifidobacteria produce these enzymes to preferentially utilize the oligosaccharides present in the intestinal ecosystem. PMID:16233817

  4. Prognostic comparison between mucinous and nonmucinous adenocarcinoma in colorectal cancer.

    PubMed

    Park, Jong Seob; Huh, Jung Wook; Park, Yoon Ah; Cho, Yong Beom; Yun, Seong Hyeon; Kim, Hee Cheol; Lee, Woo Yong; Chun, Ho-Kyung

    2015-04-01

    Mucinous adenocarcinoma (MAC) is a histological subtype of colorectal cancer. The oncologic behavior of MAC differs from nonmucinous adenocarcinoma (non-MAC). Our aim in this study was to characterize patients with colorectal MAC through evaluation of a large, institutional-based cohort with long-term follow-up. A total of 6475 patients with stages I to III colorectal cancer who underwent radical surgery were enrolled from January 2000 to December 2010. Prognostic comparison between MAC (n = 274, 4.2%) and non-MAC was performed. The median follow-up period was 48.0 months. Patients with MAC were younger than those without MAC (P = 0.012) and had larger tumor size (P < 0.001), higher preoperative carcinoembryonic antigen (P < 0.001), higher pathologic T stage (P < 0.001), more right-sided colon cancer (49.3%, P < 0.001), and more frequent high-frequency microsatellite instability (10.2%, P < 0.001). Five-year disease-free survival (DFS) was 76.5% in the MAC group and 83.2% in the non-MAC group (P = 0.008), and 5-year overall survival was 81.4% versus 87.4%, respectively (P = 0.005). Mucinous histology (MAC vs non-MAC) in the entire cohort was not an independent prognostic factor of DFS but had a statistical tendency (P = 0.071). In subgroup analysis of colon cancer without rectal cancer, mucinous histology was an independent prognostic factor (P = 0.026). MAC was found at more advanced stage, located mainly at the right side and was an independent factor of survival in colon cancer. Because of the unique biological behavior of MAC, patients with MAC require special consideration during follow-up. PMID:25881840

  5. Incidental Finding of a Rare Urachal Pathology: Urachal Mucinous Cystic Tumour of Low Malignant Potential

    PubMed Central

    Wang, Luke L.; Liddell, Heath; Tanny, Sharman Tan; Norris, Briony; Appu, Sree; Pan, David

    2016-01-01

    Urachal mucinous cystic tumours are rare pathological findings with only 23 previously reported cases in the literature. We present the case of a 54-year-old man with an incidentally found urachal mucinous cystic tumour laparoscopically excised. With its known potential to cause pseudomyxoma peritonei, complete surgical excision is important. Long-term cystoscopic and radiological surveillance is also required. PMID:26881171

  6. Different staining patterns of ovarian Brenner tumor and the associated mucinous tumor.

    PubMed

    Roma, Andres A; Masand, Ramya P

    2015-02-01

    The association of ovarian Brenner tumors and adjacent mucinous tumors is well known but not completely understood. In this study, we analyzed immunohistochemical markers on Brenner tumors and their associated mucinous tumor to explore Mullerian as well as Wolffian and germ cell derivation and determine if the mucinous component is independent or related to the Brenner tumor. Of 32 consecutive cases of Brenner tumors, 8 were identified with significant mucinous component, and 7 additional cases included foci of mucinous epithelium within the Brenner transitional nests. All Brenner tumors were diffusely positive for GATA3 and negative for Paired box gene 8, PAX2, and Sal-like protein 4. Interestingly, the areas of mucinous epithelium as well as mucinous tumors, intermixed and adjacent to the Brenner tumor, were negative for all 4 markers; however, occasional basal-like cells retained expression of GATA3. The immunoprofile of mucinous tumors associated with Brenner tumors shares the lack of Mullerian markers PAX2 and Paired box gene 8 with the Brenner tumor but differs in the expression of GATA3 only in the Brenner tumor component. PMID:25596159

  7. Mucin aggregation from a rod-like meso-scale model

    NASA Astrophysics Data System (ADS)

    Moreno, Nicolas; Perilla, Jairo E.; Colina, Coray M.; Lísal, Martin

    2015-05-01

    Dissipative particle dynamics, a meso-scale particle-based model, was used to study the aggregation of mucins in aqueous solutions. Concentration, strength of the mucin-water interactions, as well as the effects of size, shape, and composition of the model molecules were studied. Model proteins were represented as rod-like objects formed by coarse-grained beads. In the first model, only one type of beads formed the mucin. It was found that all the surfaces were available to form aggregates and the conformation of the aggregates was a function of the strength of the mucin-water interaction. With this model, the number of aggregates was unaffected by the initial position of the mucins in the simulation box, except for the lowest mucin concentration. In a more refined mucin model, two kinds of beads were used in the molecule in order to represent the existence of cysteine-like terminal groups in the actual molecule. With this new scheme, aggregation took place by the interaction of the terminal groups between model molecules. The kinetic analysis of the evolution of the number of aggregates with time was also studied for both mucin models.

  8. Antigenic and structural features of goblet-cell mucin of human small intestine.

    PubMed Central

    Mantle, M; Forstner, G G; Forstner, J F

    1984-01-01

    With the use of a newly developed solid-phase radioimmunoassay method, the major antigenic determinants of human small-intestinal goblet-cell mucin were investigated and related to the overall tertiary structure of the mucin. Preliminary hapten inhibition studies with various oligosaccharides of known sequence and structure suggested that the determinants did not reside in carbohydrate. Exhaustive thiol reduction, however, almost abolished antigenicity, caused breakdown of the mucin into small heterogeneous glycopeptides, and liberated a 'link' peptide of Mr 118000. Western 'blots' of reduced mucin from polyacrylamide gels on to nitrocellulose sheets showed that a small amount of residual antigenicity remained in large-Mr glycopeptides (Mr greater than 200000). The 'link' peptide was not antigenic. Timed Pronase digestion of native mucin resulted in a progressive loss of antigenic determinants. Gel electrophoresis revealed that after 8h of digestion the 118000-Mr peptide had disappeared, whereas antigenicity, which was confined to large-Mr glycopeptides, was destroyed much more slowly with time (70% by 24h, 100% by 72h). Despite the loss of antigenicity, 72h-Pronase-digested glycopeptides retained all of the carbohydrate of the native mucin. Therefore the antibody to human small-intestinal mucin appears to recognize a 'naked' (non-glycosylated and Pronase-susceptible) peptide region(s) of mucin glycopeptides. For full antigenicity, however, disulphide bonds are required to stabilize a specific three-dimensional configuration of the 'naked' region. Images Fig. 4. Fig. 6. PMID:6199017

  9. Effect of reserpine on the histochemical and biochemical properties of rat intestinal mucin

    SciTech Connect

    Forstner, J.; Roomi, N.; Khorasani, R.; Kuhns, W.; Forstner, G. )

    1991-04-01

    Biochemical and histochemical parameters of intestinal mucins were examined in control and reserpine-treated rats. An assay for intestinal mucin sulfotransferase was developed and the activity shown to increase 3.4 times over control levels in rats given intraperitonal reserpine (0.5 mg/kg body wt) daily for 7 days. Histochemical staining of intestinal sections revealed an increase in sulfomucins in goblet cells of reserpine-treated rats. The effects were prominent as early as 1 day following injection, particularly in the distal third of the small intestine, and during the next 6 days these changes spread progressively to the middle and proximal thirds. After 3 days of treatment mucins were purified from each intestinal segment and compared to control mucins with respect to composition and (35S)NaSO{sub 4} incorporation. Although individual amino acid and carbohydrate molar ratios were unchanged, the total carbohydrate and sulfate content of mucins in treated animals was elevated (two to three times above control) in the middle and distal thirds of the intestine. In vivo ({sup 35}S)SO{sub 4} incorporation into these mucins was also proportionaltely elevated, and was targetted to O-linked oligosaccharide side chains. These findings are consistent with an action of reserpine causing an increased production of mucin which is enriched in glycoprotein components bearing sulfated oligosaccharide chains. The relevance of these findings to the production of hypersulfated and hyperglycosylated mucins in cystic fibrosis is discussed.

  10. Apoptosis and the Airway Epithelium

    PubMed Central

    White, Steven R.

    2011-01-01

    The airway epithelium functions as a barrier and front line of host defense in the lung. Apoptosis or programmed cell death can be elicited in the epithelium as a response to viral infection, exposure to allergen or to environmental toxins, or to drugs. While apoptosis can be induced via activation of death receptors on the cell surface or by disruption of mitochondrial polarity, epithelial cells compared to inflammatory cells are more resistant to apoptotic stimuli. This paper focuses on the response of airway epithelium to apoptosis in the normal state, apoptosis as a potential regulator of the number and types of epithelial cells in the airway, and the contribution of epithelial cell apoptosis in important airways diseases. PMID:22203854

  11. Extraglottic airway devices: A review

    PubMed Central

    Ramaiah, Ramesh; Das, Debasmita; Bhananker, Sanjay M; Joffe, Aaron M

    2014-01-01

    Extraglottic airway devices (EAD) have become an integral part of anesthetic care since their introduction into clinical practice 25 years ago and have been used safely hundreds of millions of times, worldwide. They are an important first option for difficult ventilation during both in-hospital and out-of-hospital difficult airway management and can be utilized as a conduit for tracheal intubation either blindly or assisted by another technology (fiberoptic endoscopy, lightwand). Thus, the EAD may be the most versatile single airway technique in the airway management toolbox. However, despite their utility, knowledge regarding specific devices and the supporting data for their use is of paramount importance to patient's safety. In this review, number of commercially available EADs are discussed and the reported benefits and potential pitfalls are highlighted. PMID:24741502

  12. United airway disease: current perspectives

    PubMed Central

    Giavina-Bianchi, Pedro; Aun, Marcelo Vivolo; Takejima, Priscila; Kalil, Jorge; Agondi, Rosana Câmara

    2016-01-01

    Upper and lower airways are considered a unified morphological and functional unit, and the connection existing between them has been observed for many years, both in health and in disease. There is strong epidemiologic, pathophysiologic, and clinical evidence supporting an integrated view of rhinitis and asthma: united airway disease in the present review. The term “united airway disease” is opportune, because rhinitis and asthma are chronic inflammatory diseases of the upper and lower airways, which can be induced by allergic or nonallergic reproducible mechanisms, and present several phenotypes. Management of rhinitis and asthma must be jointly carried out, leading to better control of both diseases, and the lessons of the Allergic Rhinitis and Its Impact on Asthma initiative cannot be forgotten. PMID:27257389

  13. Eosinophilic phenotypes of airway disease.

    PubMed

    Pavord, Ian D

    2013-12-01

    Our understanding of the clinical implications of eosinophilic airway inflammation has increased significantly over the last 20 years, aided by the development of noninvasive means to assess it. This pattern of airway inflammation can occur in a diverse range of airway diseases. It is associated with a positive response to corticosteroids and a high risk of preventable exacerbations. Our new understanding of the role of eosinophilic airway inflammation has paved the way for the clinical development of a number of more specific inhibitors that may become new treatment options. Different definitions, ideas of disease, and adoption of biomarkers that are not well known are necessary to fully realize the potential of these treatments. PMID:24313765

  14. Imaging of the Distal Airways

    PubMed Central

    Tashkin, Donald P.; de Lange, Eduard E.

    2009-01-01

    Imaging techniques of the lung continues to advance with improving ability to image the more distal airways. Two imaging techniques are reviewed, computerized tomography and magnetic resonance with hyperpolarized helium-3. PMID:19962040

  15. The Virtual Pediatric Airways Workbench.

    PubMed

    Quammen, Cory W; Taylor Ii, Russell M; Krajcevski, Pavel; Mitran, Sorin; Enquobahrie, Andinet; Superfine, Richard; Davis, Brad; Davis, Stephanie; Zdanski, Carlton

    2016-01-01

    The Virtual Pediatric Airways Workbench (VPAW) is a patient-centered surgical planning software system targeted to pediatric patients with airway obstruction. VPAW provides an intuitive surgical planning interface for clinicians and supports quantitative analysis regarding prospective surgeries to aid clinicians deciding on potential surgical intervention. VPAW enables a full surgical planning pipeline, including importing DICOM images, segmenting the airway, interactive 3D editing of airway geometries to express potential surgical treatment planning options, and creating input files for offline geometric analysis and computational fluid dynamics simulations for evaluation of surgical outcomes. In this paper, we describe the VPAW system and its use in one case study with a clinician to successfully describe an intended surgery outcome. PMID:27046595

  16. [Mucinous adenocarcinoma of the appendix. Report of a case].

    PubMed

    Wolniczak, Isabella; Cáceres Del Águila, Alonso; Santillana Callirgos, Juan Alberto

    2016-01-01

    Mucinous adenocarcinoma of the appendix is a rare neoplasm with an incidence rate of 0.08% of all malignancies. The diagnosis is usually made by biopsy because its clinical presentation may mimic other diseases of structures located in the right lower quadrant. Currently, the treatment is still controversial, being surgery the best option. This report describes a patient with a history of appendectomy 27 years ago that is hospitalized for a painful mass in the lower abdomen associated with carcinoembryonic antigen of 138 ng/dl. PMID:27409095

  17. Colonic mucin composition in primates. Selective alterations associated with spontaneous colitis in the cotton-top tamarin.

    PubMed

    Podolsky, D K; Madara, J L; King, N; Sehgal, P; Moore, R; Winter, H S

    1985-01-01

    Heterogeneity of colonic mucin glycoprotein was examined in rectal mucosal biopsy specimens from a variety of primate species (Saguinus oedipus, n = 18; Macaca mulatta, n = 2; Macaca fascicularis, n = 2; Aotus trivirgatus, n = 2; Saimiri sciureus, n = 2; and Callithrix jacchus, n = 2). After initial separation of radiolabeled mucin and nonmucin glycoproteins solubilized from mucosal biopsy specimens, at least five labeled mucin components were found in monkey rectal mucosa in contrast to the six mucin fractions observed in the human colon. Although primates consistently lacked the earliest eluting component present in human colonic mucin, other mucin components cochromatographed with comparable fractions previously identified in human colonic biopsy specimens. The relative proportions of each fraction were consistent throughout all species except the cotton-top tamarin (S. oedipus), an animal that develops a chronic colitis. The cotton-top tamarin was found to have a markedly reduced amount of one mucin component (IV) in a manner analogous to the reduction in a human mucin fraction previously noted in patients with ulcerative colitis. Sequential evaluation of mucin profiles in cotton-top tamarins (n = 12) treated with sulfasalazine (50 mg/kg X day) or placebo in a 10-wk double-blind crossover study demonstrated the persistence of the selective reduction in tamarin species IV unrelated to disease activity. In contrast, the relative amount of tamarin mucin III was greater in association with increased disease activity than that observed in association with reduced disease activity (46% +/- 11% total mucin vs. 19% +/- 7% total mucin posttreatment). PMID:3917260

  18. Mucin-1 and its relation to grade, stage and survival in ovarian carcinoma patients

    PubMed Central

    2012-01-01

    Background Mucin-1 is known to be over-expressed by various human carcinomas and is shed into the circulation where it can be detected in patient’s serum by specific anti-Mucin-1 antibodies, such as the tumour marker assays CA 15–3 and CA 27.29. The prognostic value of Mucin-1 expression in ovarian carcinoma remains uncertain. One aim of this study was to compare the concentrations of Mucin-1 in a cohort of patients with either benign or malignant ovarian tumours detected by CA 15–3 and CA 27.29. Another aim of this study was to evaluate Mucin-1 expression by immunohistochemistry in a different cohort of ovarian carcinoma patients with respect to grade, stage and survival. Methods Patients diagnosed with and treated for ovarian tumours were included in the study. Patient characteristics, histology including histological subtype, tumour stage, grading and follow-up data were available from patient records. Serum Mucin-1 concentrations were measured with ELISA technology detecting CA 15–3 and CA 27.29, Mucin-1 tissue expression was determined by immunohistochemistry using the VU4H5 and VU3C6 anti-Mucin-1 antibodies. Statistical analysis was performed by using SPSS 18.0. Results Serum samples of 118 patients with ovarian tumours were obtained to determine levels of Mucin-1. Median CA 15–3 and CA 27.29 concentrations were significantly higher in patients with malignant disease (p< 0.001) than in patients with benign disease. Paraffin-embedded tissue of 154 patients with ovarian carcinoma was available to determine Mucin-1 expression. The majority of patients presented with advanced stage disease at primary diagnosis. Median follow-up time was 11.39 years. Immunohistochemistry results for VU4H5 showed significant differences with respect to tumour grade, FIGO stage and overall survival. Patients with negative expression had a mean overall survival of 9.33 years compared to 6.27 years for patients with positive Mucin-1 expression. Conclusions This study found

  19. Fetal Exposure of Rhesus Macaques to Bisphenol A Alters Cellular Development of the Conducting Airway by Changing Epithelial Secretory Product Expression

    PubMed Central

    Murphy, Shannon R.; Boetticher, Miriam V.; VandeVoort, Catherine A.

    2013-01-01

    Background: Bisphenol A (BPA) exposure early in life results in organizational changes in reproductive organs, but the effect of BPA on conducting airway cellular maturation has not been studied. Late gestation is characterized by active differentiation of secretory cells in the lung epithelium. Objective: We evaluated the hypothesis that BPA exposure disrupts epithelial secretory cell development in the fetal conducting airway of the rhesus macaque. Methods: We exposed animals to BPA during either the second (early term) or the third (late term) trimester. There were four treatment groups: a) sham control early term, b) sham control late term, c) BPA early term (BPA-early), and d) BPA late term (BPA-late). Because cellular maturation occurs nonuniformly in the lung, we defined mRNA and protein expression by airway level using microdissection. Results: BPA exposure of the dam during late term significantly accelerated secretory cell maturation in the proximal airways of the fetus; both Clara cell secretory protein (CCSP) and MUC5AC/5B mRNA and protein expression increased. Conclusions: BPA exposure during late gestation accelerates secretory cell maturation in the proximal conducting airways. We identified a critical window of fetal susceptibility for BPA effects on lung epithelial cell maturation in the third trimester. This is of environmental health importance because increases in airway mucins are hallmarks of a number of childhood lung diseases that may be affected by BPA exposure. PMID:23757601

  20. Brief mechanical ventilation causes differential epithelial repair along the airways of fetal, preterm lambs.

    PubMed

    Deptula, Nicole; Royse, Emily; Kemp, Matthew W; Miura, Yuichiro; Kallapur, Suhas G; Jobe, Alan H; Hillman, Noah H

    2016-08-01

    Mechanical ventilation of preterm lambs causes lung inflammation and injury to the airway epithelium, which is repaired by 15 days after ventilation. In mice, activated basal cells (p63+, KRT14+, KRT8+) initiate injury repair to the trachea, whereas club cells coordinate distal airway repair. In both human and sheep, basal cells line the pseudostratified airways to the distal bronchioles with club cells only present in terminal bronchioles. Mechanical ventilation causes airway epithelial injury that is repaired through basal cell activation in the fetal lung. Ewes at 123 ± 1 day gestational age had the head and chest of the fetus exteriorized and tracheostomy placed. With placental circulation intact, fetal lambs were mechanically ventilated with up to 15 ml/kg for 15 min with 95% N2/5% CO2 Fetal lambs were returned to the uterus for up to 24 h. The trachea, left mainstem bronchi, and peripheral lung were evaluated for epithelial injury and cellular response consistent with repair. Peripheral lung tissue had inflammation, pro-inflammatory cytokine production, epithelial growth factor receptor ligand upregulation, increased p63 expression, and proliferation of pro-SPB, TTF-1 positive club cells. In bronchi, KRT14 and KRT8 mRNA increased without increases in Notch pathway mRNA or proliferation. In trachea, mRNA increased for Notch ligands, SAM pointed domain-containing Ets transcription factor and mucin 5B, but not for basal cell markers. A brief period of mechanical ventilation causes differential epithelial activation between trachea, bronchi, and peripheral lung. The repair mechanisms identified in adult mice occur at different levels of airway branching in fetal sheep with basal and club cell activation. PMID:27343193

  1. Mucinous tumors of the ovary: current thoughts on diagnosis and management.

    PubMed

    Brown, Jubilee; Frumovitz, Michael

    2014-06-01

    Mucinous tumors of the ovary represent a spectrum of neoplastic disorders, including benign mucinous cystadenoma, pseudomyxoma peritonei, mucinous tumors of low malignant potential (borderline), and invasive mucinous ovarian carcinoma. These tumors are related closely to each other and are distinct from other histologic subtypes of epithelial ovarian neoplasms from a clinical, histologic, and molecular standpoint. A continuum appears to be present from benign to borderline to malignant, which is different from other types of epithelial ovarian cancer. Mutational profiles are also distinct, as KRAS mutations are common, but p53 and BRCA mutations are infrequent. These characteristics lead to specific biologic behavior and guide both clinical management and research efforts in patients with mucinous ovarian tumors. PMID:24777667

  2. Residual mucin and response after neoadjuvant chemotherapy (NAC) in breast cancer.

    PubMed

    Jove, Maria; Verghese, Eldo; Sharma, Nisha; Lane, Sally

    2016-01-01

    Neoadjuvant chemotherapy (NAC) is the standard of care for patients with breast cancer with inoperable disease or smaller tumours who might benefit from a conservative surgery after downstaging of their disease. Nevertheless, evidence shows that preoperative and postoperative chemotherapy are equivalent in terms of long-term survival. Response and histological changes after NAC have been widely studied in invasive ductal carcinoma not otherwise specified, but there is a paucity of characterisation of patterns of response to chemotherapy in less frequent histological types. We report extensive residual mucin deposits after chemotherapy in a woman with locally advanced breast cancer and a prominent mucinous component at diagnosis. Interestingly, residual mucin was co-located with the initial tumour, in the breast as well as in the axillary lymph nodes. The distribution of mucin may be a valuable marker of the extent of mucinous carcinomas prior to NAC. PMID:27154986

  3. Removal of endotracheal tube obstruction with a secretion clearance device.

    PubMed

    Mietto, Cristina; Foley, Kevin; Salerno, Lindsay; Oleksak, Jenna; Pinciroli, Riccardo; Goverman, Jeremy; Berra, Lorenzo

    2014-09-01

    Accumulation of secretions may suddenly occlude an endotracheal tube (ETT), requiring immediate medical attention. The endOclear catheter (Endoclear LLC, Petoskey, Michigan) is a novel device designed to clear mucus and debris from an ETT and restore luminal patency. We present 3 subsequent cases of life-threatening partial ETT occlusions recorded over a period of 6 months at Massachusetts General Hospital. After conventional methods (standard tracheal suctioning and bronchoscopy) failed, the endOclear was used, with successful restoration of the airways in all 3 cases. The respiratory conditions rapidly improved, and all 3 patients tolerated the ETT-cleaning maneuver. These results show that such a device is safe and easy to use during an emergency airway situation for efficient and rapid removal of secretions from obstructed ETTs by respiratory therapists. PMID:24368863

  4. Airway obstruction with cricoid pressure.

    PubMed

    Hartsilver, E L; Vanner, R G

    2000-03-01

    Cricoid pressure may cause airway obstruction. We investigated whether this is related to the force applied and to the technique of application. We recorded expired tidal volumes and inflation pressures during ventilation via a face-mask and oral airway in 52 female patients who were anaesthetised and about to undergo elective surgery. An inspired tidal volume of 900 ml was delivered using a ventilator. Ventilation was assessed under five different conditions: no cricoid pressure, backwards cricoid pressure applied with a force of 30 N, cricoid pressure applied in an upward and backward direction with a force of 30 N, backwards cricoid pressure with a force of 44 N and through a tracheal tube. An expired tidal volume of < 200 ml was taken to indicate airway obstruction. Airway obstruction did not occur without cricoid pressure, but did occur in one patient (2%) with cricoid pressure at 30 N, in 29 patients (56%) with 30 N applied in an upward and backward direction and in 18 (35%) patients with cricoid pressure at 44 N. Cricoid pressure applied with a force of 44 N can cause airway obstruction but if cricoid pressure is applied with a force of 30 N, airway obstruction occurs less frequently (p = 0.0001) unless the force is applied in an upward and backward direction. PMID:10671836

  5. Surfactant and allergic airway inflammation.

    PubMed

    Winkler, Carla; Hohlfeld, Jens M

    2013-01-01

    Pulmonary surfactant is a complex mixture of unique proteins and lipids that covers the airway lumen. Surfactant prevents alveolar collapse and maintains airway patency by reducing surface tension at the air-liquid interface. Furthermore, it provides a defence against antigen uptake by binding foreign particles and enhancing cellular immune responses. Allergic asthma is associated with chronic airway inflammation and presents with episodes of airway narrowing. The pulmonary inflammation and bronchoconstriction can be triggered by exposure to allergens or pathogens present in the inhaled air. Pulmonary surfactant has the potential to interact with various immune cells which orchestrate allergen- or pathogen-driven episodes of airway inflammation. The complex nature of surfactant allows multiple sites of interaction, but also makes it susceptible to external alterations, which potentially impair its function. This duality of modulating airway physiology and immunology during inflammatory conditions, while at the same time being prone to alterations accompanied by restricted function, has stimulated numerous studies in recent decades, which are reviewed in this article. PMID:23896983

  6. Allergen-induced airway remodeling is impaired in galectin-3 deficient mice1

    PubMed Central

    Ge, Xiao Na; Bahaie, Nooshin S.; Kang, Bit Na; Hosseinkhani, Reza M.; Ha, Sung Gil; Frenzel, Elizabeth M.; Liu, Fu-Tong; Rao, Savita P.; Sriramarao, P.

    2010-01-01

    The role played by the β-galactoside-binding lectin galectin-3 (Gal-3) in airway remodeling, a characteristic feature of asthma that leads to airway dysfunction and poor clinical outcome in humans, was investigated in a murine model of chronic allergic airway inflammation. Wild-type (WT) and Gal-3 knock-out (KO) mice were subjected to repetitive allergen challenge with ovalbumin (OVA) up to 12 weeks and bronchoalveolar lavage fluid (BALF) and lung tissue collected after the last challenge were evaluated for cellular features associated with airway remodeling. Compared to WT mice, chronic OVA challenge in Gal-3 KO mice resulted in diminished remodeling of the airways with significantly reduced mucus secretion, sub-epithelial fibrosis, smooth muscle thickness, and peribronchial angiogenesis. The higher degree of airway remodeling in WT mice was associated with higher Gal-3 expression in the BALF as well as lung tissue. Cell counts in BALF and lung immunohistology demonstrated that eosinophil infiltration in OVA-challenged Gal-3 KO mice was significantly reduced compared to WT mice. Evaluation of cellular mediators associated with eosinophil recruitment and airway remodeling revealed that levels of eotaxin-1, IL-5, IL-13, FIZZ1 and TGF-β were substantially lower in Gal-3 KO mice. Finally, leukocytes from Gal-3 KO mice demonstrated decreased trafficking (rolling) on vascular endothelial adhesion molecules compared to WT cells. Overall, these studies demonstrate that Gal-3 is an important lectin that promotes airway remodeling via airway recruitment of inflammatory cells, specifically eosinophils, and the development of a Th2 phenotype as well as increased expression of eosinophil-specific chemokines, pro-fibrogenic and angiogenic mediators. PMID:20543100

  7. Matrix stiffness-modulated proliferation and secretory function of the airway smooth muscle cells.

    PubMed

    Shkumatov, Artem; Thompson, Michael; Choi, Kyoung M; Sicard, Delphine; Baek, Kwanghyun; Kim, Dong Hyun; Tschumperlin, Daniel J; Prakash, Y S; Kong, Hyunjoon

    2015-06-01

    Multiple pulmonary conditions are characterized by an abnormal misbalance between various tissue components, for example, an increase in the fibrous connective tissue and loss/increase in extracellular matrix proteins (ECM). Such tissue remodeling may adversely impact physiological function of airway smooth muscle cells (ASMCs) responsible for contraction of airways and release of a variety of bioactive molecules. However, few efforts have been made to understand the potentially significant impact of tissue remodeling on ASMCs. Therefore, this study reports how ASMCs respond to a change in mechanical stiffness of a matrix, to which ASMCs adhere because mechanical stiffness of the remodeled airways is often different from the physiological stiffness. Accordingly, using atomic force microscopy (AFM) measurements, we found that the elastic modulus of the mouse bronchus has an arithmetic mean of 23.1 ± 14 kPa (SD) (median 18.6 kPa). By culturing ASMCs on collagen-conjugated polyacrylamide hydrogels with controlled elastic moduli, we found that gels designed to be softer than average airway tissue significantly increased cellular secretion of vascular endothelial growth factor (VEGF). Conversely, gels stiffer than average airways stimulated cell proliferation, while reducing VEGF secretion and agonist-induced calcium responses of ASMCs. These dependencies of cellular activities on elastic modulus of the gel were correlated with changes in the expression of integrin-β1 and integrin-linked kinase (ILK). Overall, the results of this study demonstrate that changes in matrix mechanics alter cell proliferation, calcium signaling, and proangiogenic functions in ASMCs. PMID:25724668

  8. Expression of IL-4/IL-13 receptors in differentiating human airway epithelial cells.

    PubMed

    White, Steven R; Martin, Linda D; Stern, Randi; Laxman, Bharathi; Marroquin, Bertha A

    2010-11-01

    IL-4 and IL-13 elicit several important responses in airway epithelium including chemokine secretion and mucous secretion that may contribute to airway inflammation, cell migration, and differentiation. These cytokines have overlapping but not identical effector profiles likely due to shared subunits in their receptor complexes. These receptors are variably described in epithelial cells, and the relative expression, localization, and function of these receptors in differentiated and repairing epithelial cells are not clear. We examined IL-4/IL-13 receptor expression and localization in primary airway epithelial cells collected from normal human lungs and grown under conditions yielding both undifferentiated and differentiated cells inclusive of basal, goblet, and ciliated cell phenotypes. Gene expression of the IL-4Rα, IL-2Rγc, IL-13Rα1, and IL-13Rα2 receptor subunits increased with differentiation, but different patterns of localization and protein abundance were seen for each subunit based on both differentiation and the cell subtypes present. Increased expression of receptor subunits observed in more differentiated cells was associated with more substantial functional responses to IL-4 stimulation including increased eotaxin-3 expression and accelerated migration after injury. We demonstrate substantial differences in IL-4/IL-13 receptor subunit expression and responsiveness to IL-4 based on the extent of airway epithelial cell differentiation and suggest that these differences may have functional consequences in airway inflammation. PMID:20729386

  9. Intestinal Goblet Cells and Mucins in Health and Disease: Recent Insights and Progress

    PubMed Central

    Ho, Samuel B.

    2010-01-01

    The mucus layer coating the gastrointestinal tract is the front line of innate host defense, largely because of the secretory products of intestinal goblet cells. Goblet cells synthesize secretory mucin glycoproteins (MUC2) and bioactive molecules such as epithelial membrane-bound mucins (MUC1, MUC3, MUC17), trefoil factor peptides (TFF), resistin-like molecule β (RELMβ), and Fc-γ binding protein (Fcgbp). The MUC2 mucin protein forms trimers by disulfide bonding in cysteine-rich amino terminal von Willebrand factor (vWF) domains, coupled with crosslinking provided by TFF and Fcgbp proteins with MUC2 vWF domains, resulting in a highly viscous extracellular layer. Colonization by commensal intestinal microbiota is limited to an outer “loose” mucus layer, and interacts with the diverse oligosaccharides of mucin glycoproteins, whereas an “inner” adherent mucus layer is largely devoid of bacteria. Defective mucus layers resulting from lack of MUC2 mucin, mutated Muc2 mucin vWF domains, or from deletion of core mucin glycosyltransferase enzymes in mice result in increased bacterial adhesion to the surface epithelium, increased intestinal permeability, and enhanced susceptibility to colitis caused by dextran sodium sulfate. Changes in mucin gene expression and mucin glycan structures occur in cancers of the intestine, contributing to diverse biologic properties involved in the development and progression of cancer. Further research is needed on identification and functional significance of various components of mucus layers and the complex interactions among mucus layers, microbiota, epithelial cells, and the underlying innate and adaptive immunity. Further elucidation of the regulatory mechanisms involved in mucin changes in cancer and inflammation may lead to the development of novel therapeutic approaches. PMID:20703838

  10. Rectal Cancer: Mucinous Carcinoma on Magnetic Resonance Imaging Indicates Poor Response to Neoadjuvant Chemoradiation

    SciTech Connect

    Oberholzer, Katja; Menig, Matthias; Kreft, Andreas; Schneider, Astrid; Junginger, Theodor; Heintz, Achim; Kreitner, Karl-Friedrich; Hoetker, Andreas M.; Hansen, Torsten; Dueber, Christoph; Schmidberger, Heinz

    2012-02-01

    Purpose: To assess response of locally advanced rectal carcinoma to chemoradiation with regard to mucinous status and local tumor invasion found at pretherapeutic magnetic resonance imaging (MRI). Methods and Materials: A total of 88 patients were included in this prospective study of patients with advanced mrT3 and mrT4 carcinomas. Carcinomas were categorized by MRI as mucinous (mucin proportion >50% within the tumor volume), and as nonmucinous. Patients received neoadjuvant chemoradiation consisting of 50.4 Gy (1.8 Gy/fraction) and 5-fluorouracil on Days 1 to 5 and Days 29 to 33. Therapy response was assessed by comparing pretherapeutic MRI with histopathology of surgical specimens (minimum distance between outer tumor edge and circumferential resection margin = CRM, T, and N category). Results: A mucinous carcinoma was found in 21 of 88 patients. Pretherapeutic mrCRM was 0 mm (median) in the mucinous and nonmucinous group. Of the 88 patients, 83 underwent surgery with tumor resection. The ypCRM (mm) at histopathology was significantly lower in mucinous carcinomas than in nonmucinous carcinomas (p {<=} 0.001). Positive resection margins (ypCRM {<=} 1 mm) were found more frequently in mucinous carcinomas than in nonmucinous ones (p {<=} 0.001). Treatment had less effect on local tumor stage in mucinous carcinomas than in nonmucinous carcinomas (for T downsizing, p = 0.012; for N downstaging, p = 0.007). Disease progression was observed only in patients with mucinous carcinomas (n = 5). Conclusion: Mucinous status at pretherapeutic MRI was associated with a noticeably worse response to chemoradiation and should be assessed by MRI in addition to local tumor staging to estimate response to treatment before it is initiated.

  11. Cytopathological Analysis of Cyst Fluid Enhances Diagnostic Accuracy of Mucinous Pancreatic Cystic Neoplasms

    PubMed Central

    Utomo, Wesley K.; Braat, Henri; Bruno, Marco J.; van Eijck, Casper H.J.; Koerkamp, Bas Groot; Krak, Nanda C.; van de Vreede, Adriaan; Fuhler, Gwenny M.; Peppelenbosch, Maikel P.; Biermann, Katharina

    2015-01-01

    Abstract Widespread use of cross-sectional imaging and increasing age of the general population has increased the number of detected pancreatic cystic lesions. However, several pathological entities with a variety in malignant potential have to be discriminated to allow clinical decision making. Discrimination between mucinous pancreatic cystic neoplasms (PCNs) and nonmucinous pancreatic lesions is the primary step in the clinical work-up, as malignant transformation is mostly associated with mucinous PCN. We performed a retrospective analysis of all resected PCN in our tertiary center from 2000 to 2014, to evaluate preoperative diagnostic performance and the results of implementation of the consensus guidelines over time. This was followed by a prospective cohort study of patients with an undefined pancreatic cyst, where the added value of cytopathological mucin evaluation to carcinoembryonic antigen (CEA) in cyst fluid for the discrimination of mucinous PCN and nonmucinous cysts was investigated. Retrospective analysis showed 115 patients operated for a PCN, with a correct preoperative classification in 96.2% of the patients. High-grade dysplasia or invasive carcinoma was observed in only 32.3% of mucinous PCN. In our prospective cohort (n = 71), 57.7% of patients were classified as having a mucinous PCN. CEA ≥192 ng/mL had an accuracy of 63.4%, and cytopathological mucin evaluation an accuracy of 73.0%. Combining these 2 tests further improved diagnostic accuracy of a mucinous PCN to 76.8%. CEA level and mucin evaluation were not predictive of the degree of dysplasia. These findings show that adding cytopathology to cyst fluid biochemistry improves discrimination between mucinous PCN and nonmucinous cysts.

  12. Penetration of cefotaxime into respiratory secretions.

    PubMed Central

    Fick, R B; Alexander, M R; Prince, R A; Kasik, J E

    1987-01-01

    The objective of this study was to quantitate cefotaxime and its active metabolite, desacetyl cefotaxime, in the distal airways and to compare these levels to concentrations in plasma. Respiratory secretions were obtained from the subsegmental level in 17 adult patients undergoing fiber-optic bronchoscopy within 2 h after receiving four doses of cefotaxime (2 g intravenously every 6 h). In 11 patients, cefotaxime levels measured by high-pressure liquid chromatography in bronchial secretions were below detectable limits (less than 0.5 mg/liter); however, levels of desacetyl cefotaxime exceeded 1.5 mg/liter in 9 of these 11 patients (range, 1.6 to 10 mg/liter). Concentrations of desacetyl cefotaxime in lung secretions (6.9 +/- 0.85 [standard error] mg/liter) was 77% of mean levels of desacetyl cefotaxime in plasma (8.9 +/- 1.26 mg/liter). In summary, concentrations of desacetyl cefotaxime in bronchial secretions are markedly higher than those of cefotaxime. PMID:3606080

  13. Human Trefoil Factor 2 Is a Lectin That Binds α-GlcNAc-capped Mucin Glycans with Antibiotic Activity against Helicobacter pylori*

    PubMed Central

    Hanisch, Franz-Georg; Bonar, David; Schloerer, Nils; Schroten, Horst

    2014-01-01

    Helicobacter pylori infection is the major cause of gastric cancer and remains an important health care challenge. The trefoil factor peptides are a family of small highly conserved proteins that are claimed to play essential roles in cytoprotection and epithelial repair within the gastrointestinal tract. H. pylori colocalizes with MUC5AC at the gastric surface epithelium, but not with MUC6 secreted in concert with TFF2 by deep gastric glands. Both components of the gastric gland secretome associate non-covalently and show increased expression upon H. pylori infection. Although blood group active O-glycans of the Lewis-type form the basis of H. pylori adhesion to the surface mucin layer and to epithelial cells, α1,4-GlcNAc-capped O-glycans on gastric mucins were proposed to inhibit H. pylori growth as a natural antibiotic. We show here that the gastric glycoform of TFF2 is a calcium-independent lectin, which binds with high specificity to O-linked α1,4-GlcNAc-capped hexasaccharides on human and porcine stomach mucin. The structural assignments of two hexasaccharide isomers and the binding active glycotope were based on mass spectrometry, linkage analysis, 1H nuclear magnetic resonance spectroscopy, glycan inhibition, and lectin competition of TFF2-mucin binding. Neoglycolipids derived from the C3/C6-linked branches of the two isomers revealed highly specific TFF2 binding to the 6-linked trisaccharide in GlcNAcα1-4Galβ1-4GlcNAcβ1-6(Fucα1-2Galβ1-3)GalNAc-ol(Structure 1). Supposedly, lectin TFF2 is involved in protection of gastric epithelia via a functional relationship to defense against H. pylori launched by antibiotic α1,4-GlcNAc-capped mucin glycans. Lectin-carbohydrate interaction may have also an impact on more general functional aspects of TFF members by mediating their binding to cell signaling receptors. PMID:25124036

  14. Ineffective correction of PPARγ signaling in cystic fibrosis airway epithelial cells undergoing repair.

    PubMed

    Bou Saab, J; Bacchetta, M; Chanson, M

    2016-09-01

    Peroxisome proliferator-activated receptor gamma (PPARγ) represents a potential target to treat airway mucus hypersecretion in cystic fibrosis (CF). We aimed to determine if PPARγ is altered in CF human airway epithelial cells (HAECs), if PPARγ contributes to mucin expression and HAEC differentiation, and if PPARγ ligand therapy corrects the CF phenotype. To this end, well-differentiated CF and NCF HAEC primary cultures were wounded to monitor the expression of key genes involved in PPARγ activation and mucus homeostasis, and to evaluate the effect of a PPARγ agonist, at different times of repair. Hydroxyprostaglandin dehydrogenase (HPGD) converts prostaglandin E2 to 15-keto PGE2 (15kPGE2), an endogenous PPARγ ligand. Interestingly, PPARγ and HPGD expression dramatically decreased in CF HAECs. These changes were accompanied by an increase in the expression of MUC5B. The correlation between PPARγ and MUC5B was confirmed in an airway epithelial cell line after CFTR knock-down. Exposure of HAECs to 15kPGE2 did not correct the CF phenotype but revealed a defect in the process of basal cell (BC) differentiation. The HPGD/PPARγ axis is deregulated in primary HAEC cultures from CF patients, which may impact the maturation of BCs to differentiated luminal cells. Importantly, PPARγ therapy was inefficient in correcting the CF defect. PMID:27484450

  15. Molecular pathology of intraductal papillary mucinous neoplasms of the pancreas

    PubMed Central

    Paini, Marina; Crippa, Stefano; Partelli, Stefano; Scopelliti, Filippo; Tamburrino, Domenico; Baldoni, Andrea; Falconi, Massimo

    2014-01-01

    Since the first description of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas in the eighties, their identification has dramatically increased in the last decades, hand to hand with the improvements in diagnostic imaging and sampling techniques for the study of pancreatic diseases. However, the heterogeneity of IPMNs and their malignant potential make difficult the management of these lesions. The objective of this review is to identify the molecular characteristics of IPMNs in order to recognize potential markers for the discrimination of more aggressive IPMNs requiring surgical resection from benign IPMNs that could be observed. We briefly summarize recent research findings on the genetics and epigenetics of intraductal papillary mucinous neoplasms, identifying some genes, molecular mechanisms and cellular signaling pathways correlated to the pathogenesis of IPMNs and their progression to malignancy. The knowledge of molecular biology of IPMNs has impressively developed over the last few years. A great amount of genes functioning as oncogenes or tumor suppressor genes have been identified, in pancreatic juice or in blood or in the samples from the pancreatic resections, but further researches are required to use these informations for clinical intent, in order to better define the natural history of these diseases and to improve their management. PMID:25110429

  16. Intraductal Papillary Mucinous Neoplasm of the Pancreas: An Update

    PubMed Central

    Xiao, Shu-Yuan

    2012-01-01

    Intraductal papillary mucinous neoplasm