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Martin F Kagnoff - One of the best experts on this subject based on the ideXlab platform.

  • role of shiga toxin versus h7 flagellin in enterohaemorrhagic escherichia coli signalling of human Colon Epithelium in vivo
    Cellular Microbiology, 2006
    Co-Authors: Yukiko Miyamoto, Mitsutoshi Iimura, James B Kaper, Alfredo G Torres, Martin F Kagnoff
    Abstract:

    Summary Enterohaemorrhagic Escherichia coli O157:H7 (EHEC) is a clinically important foodborne pathogen that Colonizes human Colon Epithelium and induces acute Colonic inflammation, but does not invade the epithelial cells. Whereas Shiga toxin (Stx) and bacterial flagellin have been studied for their ability to upregulate the production of proinflammatory chemokines by cultured human Colon cancer cell lines, the relevance of studies in Colon cancer cell lines to the production of proinflammatory signals by normal epithelial cells in EHEC-infected human Colon is not known. We show herein that Stx does not bind to human Colon Epithelium in vivo. Moreover, globotriaosylceramide (Gb3/CD77) synthase, the enzyme required for synthesis of the Gb3/CD77 receptor for Stx, was not expressed by normal or inflamed human Colon Epithelium in vivo. In contrast, Toll-like receptor (TLR) 5, the receptor for bacterial flagellin, was expressed by normal human Colon Epithelium and by Colon Epithelium in human intestinal xenografts. EHEC H7 flagellin instilled in the lumen of human Colon xenografts that contain an intact human Epithelium upregulated the expression of epithelial cell proinflammatory chemokines, which was accompanied by a subepithelial influx of neutrophils. Isogenic mutants of EHEC that lacked flagellin did not significantly upregulate prototypic neutrophil and dendritic cell chemoattractants by model human Colon epithelia, irrespective of Stx production. We conclude that EHEC H7 flagellin and not Stx is the major EHEC factor that directly upregulates proinflammatory chemokine production by human Colon Epithelium in vivo.

  • regulated production of the chemokine ccl28 in human Colon Epithelium
    American Journal of Physiology-gastrointestinal and Liver Physiology, 2004
    Co-Authors: Hiroyuki Ogawa, Mitsutoshi Iimura, Lars Eckmann, Martin F Kagnoff
    Abstract:

    The chemokine CCL28 is constitutively expressed by epithelial cells at several mucosal sites and is thought to function as a homeostatic chemoattractant of subpopulations of T cells and IgA B cells...

  • cell differentiation is a key determinant of cathelicidin ll 37 human cationic antimicrobial protein 18 expression by human Colon Epithelium
    Infection and Immunity, 2002
    Co-Authors: Kouji Hase, Lars Eckmann, John D Leopard, Nissi M Varki, Martin F Kagnoff
    Abstract:

    Antimicrobial peptides are highly conserved evolutionarily and are thought to play an important role in innate immunity at intestinal mucosal surfaces. To better understand the role of the antimicrobial peptide human cathelicidin LL-37/human cationic antimicrobial protein 18 (hCAP18) in intestinal mucosal defense, we characterized the regulated expression and production of this peptide by human intestinal Epithelium. LL-37/hCAP18 is shown to be expressed within epithelial cells located at the surface and upper crypts of normal human Colon. Little or no expression was seen within the deeper Colon crypts or within epithelial cells of the small intestine. Paralleling its expression in more differentiated epithelial cells in vivo, LL-37/hCAP18 mRNA and protein expression was upregulated in spontaneously differentiating Caco-2 human Colon epithelial cells and in HCA-7 human Colon epithelial cells treated with the cell differentiation-inducing agent sodium butyrate. LL-37/hCAP18 expression by Colon Epithelium does not require commensal bacteria, since LL-37/hCAP18 is produced with a similar expression pattern by epithelial cells in human Colon xenografts that lack a luminal microflora. LL-37/hCAP18 mRNA was not upregulated in response to tumor necrosis factor alpha, interleukin 1α (IL-1α), gamma interferon, lipopolysaccharide, or IL-6, nor did the expression patterns and levels of LL-37/hCAP18 in the Epithelium of the normal and inflamed Colon differ. On the other hand, infection of HCA-7 cells with Salmonella enterica serovar Dublin or enteroinvasive Escherichia coli modestly upregulated LL-37/hCAP18 mRNA expression. We conclude that differentiated human Colon Epithelium expresses LL-37/hCAP18 as part of its repertoire of innate defense molecules and that the distribution and regulated expression of LL-37/hCAP18 in the Colon differs markedly from that of other enteric antimicrobial peptides, such as defensins.

  • Cell Differentiation Is a Key Determinant of Cathelicidin LL-37/Human Cationic Antimicrobial Protein 18 Expression by Human Colon Epithelium
    Infection and Immunity, 2002
    Co-Authors: Kouji Hase, Lars Eckmann, John D Leopard, Nissi M Varki, Martin F Kagnoff
    Abstract:

    Antimicrobial peptides are highly conserved evolutionarily and are thought to play an important role in innate immunity at intestinal mucosal surfaces. To better understand the role of the antimicrobial peptide human cathelicidin LL-37/human cationic antimicrobial protein 18 (hCAP18) in intestinal mucosal defense, we characterized the regulated expression and production of this peptide by human intestinal Epithelium. LL-37/hCAP18 is shown to be expressed within epithelial cells located at the surface and upper crypts of normal human Colon. Little or no expression was seen within the deeper Colon crypts or within epithelial cells of the small intestine. Paralleling its expression in more differentiated epithelial cells in vivo, LL-37/hCAP18 mRNA and protein expression was upregulated in spontaneously differentiating Caco-2 human Colon epithelial cells and in HCA-7 human Colon epithelial cells treated with the cell differentiation-inducing agent sodium butyrate. LL-37/hCAP18 expression by Colon Epithelium does not require commensal bacteria, since LL-37/hCAP18 is produced with a similar expression pattern by epithelial cells in human Colon xenografts that lack a luminal microflora. LL-37/hCAP18 mRNA was not upregulated in response to tumor necrosis factor alpha, interleukin 1α (IL-1α), gamma interferon, lipopolysaccharide, or IL-6, nor did the expression patterns and levels of LL-37/hCAP18 in the Epithelium of the normal and inflamed Colon differ. On the other hand, infection of HCA-7 cells with Salmonella enterica serovar Dublin or enteroinvasive Escherichia coli modestly upregulated LL-37/hCAP18 mRNA expression. We conclude that differentiated human Colon Epithelium expresses LL-37/hCAP18 as part of its repertoire of innate defense molecules and that the distribution and regulated expression of LL-37/hCAP18 in the Colon differs markedly from that of other enteric antimicrobial peptides, such as defensins.

Hubert Wiener - One of the best experts on this subject based on the ideXlab platform.

  • Class I antiarrhythmics inhibit Na+ absorption and Cl− secretion in rabbit descending Colon Epithelium
    Naunyn-schmiedebergs Archives of Pharmacology, 2005
    Co-Authors: Herbert Plass, Klaus Turnheim, Markus Charisius, Wolfgang Wyskovsky, Florian Amor, Hubert Wiener
    Abstract:

    To clarify the mechanism of the diarrhea associated with the clinical use of antiarrhythmic drugs we assessed the effects of these agents on transepithelial Na+ absorption and Cl− secretion, on basolateral K+ conductance, and on the properties of single basolateral K+ channels of rabbit Colon Epithelium. Quinidine and propafenone, both at 10 μM, inhibited Na+ absorption by 27 and 38% respectively, compared with 50% with 5 mM Ba2+. The other tested class I antiarrhythmics disopyramide, mexiletine, lidocaine, and flecainide decreased Na+ current by 9–13%. Procainamide and the class III antiarrhythmics N-acetylprocainamide, sotalol, ibutilide, and amiodarone were no or were very weak inhibitors of Na+ absorption. Cl− secretion, stimulated with the adenosine analogue NECA (5’-N-ethylcarboxamide-adenosine), was reduced by 54% with quinidine and by 29% with propafenone compared with 100% with Ba2+. Mexiletine, lidocaine, and flecainide inhibited Cl− secretion by 10–23%, whereas the class III antiarrhythmics were no or were weak inhibitors. Those antiarrhythmics that inhibited Na+ and Cl− transport also reduced basolateral K+ conductance, determined in amphotericin B permeabilized epithelia. The activity of the high-conductance, Ca2+-activated, voltage-dependent K+ (BKCa) channel, which is primarily responsible for basolateral K+ recycling during Na+ absorption, was inhibited by 10–30 μM quinidine or propafenone in the form of a rapidly dissociating block. Mexiletine and flecainide inhibited the single channel conductance at higher concentrations; disopyramide, lidocaine, and procainamide were ineffective. In conclusion, the present evidence suggests that the diarrhea caused by class I antiarrhythmic drugs such as quinidine and propafenone is a result of a reduction in basolateral K+ conductance and inhibition of BKCa channels, thereby impeding transepithelial Na+ and water absorption.

  • class i antiarrhythmics inhibit na absorption and cl secretion in rabbit descending Colon Epithelium
    Naunyn-schmiedebergs Archives of Pharmacology, 2005
    Co-Authors: Herbert Plass, Klaus Turnheim, Markus Charisius, Wolfgang Wyskovsky, Florian Amor, Hubert Wiener
    Abstract:

    To clarify the mechanism of the diarrhea associated with the clinical use of antiarrhythmic drugs we assessed the effects of these agents on transepithelial Na+ absorption and Cl− secretion, on basolateral K+ conductance, and on the properties of single basolateral K+ channels of rabbit Colon Epithelium. Quinidine and propafenone, both at 10 μM, inhibited Na+ absorption by 27 and 38% respectively, compared with 50% with 5 mM Ba2+. The other tested class I antiarrhythmics disopyramide, mexiletine, lidocaine, and flecainide decreased Na+ current by 9–13%. Procainamide and the class III antiarrhythmics N-acetylprocainamide, sotalol, ibutilide, and amiodarone were no or were very weak inhibitors of Na+ absorption. Cl− secretion, stimulated with the adenosine analogue NECA (5’-N-ethylcarboxamide-adenosine), was reduced by 54% with quinidine and by 29% with propafenone compared with 100% with Ba2+. Mexiletine, lidocaine, and flecainide inhibited Cl− secretion by 10–23%, whereas the class III antiarrhythmics were no or were weak inhibitors. Those antiarrhythmics that inhibited Na+ and Cl− transport also reduced basolateral K+ conductance, determined in amphotericin B permeabilized epithelia. The activity of the high-conductance, Ca2+-activated, voltage-dependent K+ (BKCa) channel, which is primarily responsible for basolateral K+ recycling during Na+ absorption, was inhibited by 10–30 μM quinidine or propafenone in the form of a rapidly dissociating block. Mexiletine and flecainide inhibited the single channel conductance at higher concentrations; disopyramide, lidocaine, and procainamide were ineffective. In conclusion, the present evidence suggests that the diarrhea caused by class I antiarrhythmic drugs such as quinidine and propafenone is a result of a reduction in basolateral K+ conductance and inhibition of BKCa channels, thereby impeding transepithelial Na+ and water absorption.

  • Aldosterone and thyroid hormone modulation of α1-, β1-mRNA, and Na,K-Pump sites in rabbit distal Colon Epithelium. Evidence for a novel mechanism of escape from the effect of hyperaldosteronemia
    The Journal of Membrane Biology, 1993
    Co-Authors: Hubert Wiener, Dan A. Klaerke, Jesper M. Nielsen, Peter L. Jørgensen
    Abstract:

    Aldosterone and thyroid hormone regulation of Na,K-pump biosynthesis has been examined in the distal Colon Epithelium of rabbits. Qualitative analysis of α -subunit isoform distribution ( α 1, α 2, α 3) detected only the α 1-mRNA in the distal Colon Epithelium and outer renal medulla, while all three isoforms were observed in rabbit brain. A low-sodium diet led to a rise in serum aldosterone from 0.6 n m to 1.4–1.9 n m and an increase of α 1-mRNA to 162%, β 1-mRNA to 120%, and the number of Na,K-pump units as determined by specific [^3H]-ouabain binding to 182% of control by the second day of the diet. While aldosterone levels remained elevated, a spontaneous decrease in serum levels of T_3 and T_4 to 50–60% of control from the third day of the diet was followed by downregulation of β 1-mRNA to 55–67%, α 1-mRNA to 63–105%, and of [^3H]-ouabain binding to 103% of control, suggesting that a reduced rate of synthesis of the β 1-subunit is rate limiting for Na,K-pump biosynthesis. Substitution with T_3 (10 μg/kg) at the seventh day with transient restoration of serum T_3 to control levels, led to rapid accumulation of β 1-mRNA to 152%, of α 1-mRNA to 135%, and of the number of Na,K-pump units to 153% of control. This is consistent with thyroid hormone having a permissive role for the aldosterone stimulation of Na,K-pump biosynthesis. Reduced rates of β -subunit transcription due to low thyroid hormone levels appear to provide a mechanism for escape from the effect of hyperaldosteronemia on the number of Na,K-pump units.

  • Rabbit distal Colon Epithelium: III. Ca2+-activated K+ channels in basolateral plasma membrane vesicles of surface and crypt cells
    The Journal of Membrane Biology, 1990
    Co-Authors: Hubert Wiener, Dan A. Klaerke, Peter L. Jørgensen
    Abstract:

    In the mammalian distal Colon, the surface Epithelium is responsible for electrolyte absorption, while the crypts are the site of secretion. This study examines the properties of electrical potential-driven86Rb+ fluxes through K+ channels in basolateral membrane vesicles of surface and crypt cells of the rabbit distal Colon Epithelium. We show that Ba2+-sensitive, Ca2+-activated K+ channels are present in both surface and crypt cell derived vesicles with half-maximal activation at 5×10−7m free Ca2+. This suggests an important role of cytoplasmic Ca2+ in the regulation of the bidirectional ion fluxes in the Colon Epithelium.

Klaus Turnheim - One of the best experts on this subject based on the ideXlab platform.

  • Class I antiarrhythmics inhibit Na+ absorption and Cl− secretion in rabbit descending Colon Epithelium
    Naunyn-schmiedebergs Archives of Pharmacology, 2005
    Co-Authors: Herbert Plass, Klaus Turnheim, Markus Charisius, Wolfgang Wyskovsky, Florian Amor, Hubert Wiener
    Abstract:

    To clarify the mechanism of the diarrhea associated with the clinical use of antiarrhythmic drugs we assessed the effects of these agents on transepithelial Na+ absorption and Cl− secretion, on basolateral K+ conductance, and on the properties of single basolateral K+ channels of rabbit Colon Epithelium. Quinidine and propafenone, both at 10 μM, inhibited Na+ absorption by 27 and 38% respectively, compared with 50% with 5 mM Ba2+. The other tested class I antiarrhythmics disopyramide, mexiletine, lidocaine, and flecainide decreased Na+ current by 9–13%. Procainamide and the class III antiarrhythmics N-acetylprocainamide, sotalol, ibutilide, and amiodarone were no or were very weak inhibitors of Na+ absorption. Cl− secretion, stimulated with the adenosine analogue NECA (5’-N-ethylcarboxamide-adenosine), was reduced by 54% with quinidine and by 29% with propafenone compared with 100% with Ba2+. Mexiletine, lidocaine, and flecainide inhibited Cl− secretion by 10–23%, whereas the class III antiarrhythmics were no or were weak inhibitors. Those antiarrhythmics that inhibited Na+ and Cl− transport also reduced basolateral K+ conductance, determined in amphotericin B permeabilized epithelia. The activity of the high-conductance, Ca2+-activated, voltage-dependent K+ (BKCa) channel, which is primarily responsible for basolateral K+ recycling during Na+ absorption, was inhibited by 10–30 μM quinidine or propafenone in the form of a rapidly dissociating block. Mexiletine and flecainide inhibited the single channel conductance at higher concentrations; disopyramide, lidocaine, and procainamide were ineffective. In conclusion, the present evidence suggests that the diarrhea caused by class I antiarrhythmic drugs such as quinidine and propafenone is a result of a reduction in basolateral K+ conductance and inhibition of BKCa channels, thereby impeding transepithelial Na+ and water absorption.

  • class i antiarrhythmics inhibit na absorption and cl secretion in rabbit descending Colon Epithelium
    Naunyn-schmiedebergs Archives of Pharmacology, 2005
    Co-Authors: Herbert Plass, Klaus Turnheim, Markus Charisius, Wolfgang Wyskovsky, Florian Amor, Hubert Wiener
    Abstract:

    To clarify the mechanism of the diarrhea associated with the clinical use of antiarrhythmic drugs we assessed the effects of these agents on transepithelial Na+ absorption and Cl− secretion, on basolateral K+ conductance, and on the properties of single basolateral K+ channels of rabbit Colon Epithelium. Quinidine and propafenone, both at 10 μM, inhibited Na+ absorption by 27 and 38% respectively, compared with 50% with 5 mM Ba2+. The other tested class I antiarrhythmics disopyramide, mexiletine, lidocaine, and flecainide decreased Na+ current by 9–13%. Procainamide and the class III antiarrhythmics N-acetylprocainamide, sotalol, ibutilide, and amiodarone were no or were very weak inhibitors of Na+ absorption. Cl− secretion, stimulated with the adenosine analogue NECA (5’-N-ethylcarboxamide-adenosine), was reduced by 54% with quinidine and by 29% with propafenone compared with 100% with Ba2+. Mexiletine, lidocaine, and flecainide inhibited Cl− secretion by 10–23%, whereas the class III antiarrhythmics were no or were weak inhibitors. Those antiarrhythmics that inhibited Na+ and Cl− transport also reduced basolateral K+ conductance, determined in amphotericin B permeabilized epithelia. The activity of the high-conductance, Ca2+-activated, voltage-dependent K+ (BKCa) channel, which is primarily responsible for basolateral K+ recycling during Na+ absorption, was inhibited by 10–30 μM quinidine or propafenone in the form of a rapidly dissociating block. Mexiletine and flecainide inhibited the single channel conductance at higher concentrations; disopyramide, lidocaine, and procainamide were ineffective. In conclusion, the present evidence suggests that the diarrhea caused by class I antiarrhythmic drugs such as quinidine and propafenone is a result of a reduction in basolateral K+ conductance and inhibition of BKCa channels, thereby impeding transepithelial Na+ and water absorption.

  • basolateral potassium channels of rabbit Colon Epithelium role in sodium absorption and chloride secretion
    Biochimica et Biophysica Acta, 2002
    Co-Authors: Klaus Turnheim, Herbert Plass, Wolfgang Wyskovsky
    Abstract:

    Abstract In order to assess the role of different classes of K+ channels in recirculation of K+ across the basolateral membrane of rabbit distal Colon Epithelium, the effects of various K+ channel inhibitors were tested on the activity of single K+ channels from the basolateral membrane, on macroscopic basolateral K+ conductance, and on the rate of Na+ absorption and Cl− secretion. In single-channel measurements using the lipid bilayer reconstitution system, high-conductance (236 pS), Ca2+-activated K+ (BKCa) channels were most frequently detected; the second most abundant channel was a low-conductance K+ channel (31 pS) that exhibited channel rundown. In addition to Ba2+ and charybdotoxin (ChTX), the BKCa channels were inhibited by quinidine, verapamil and tetraethylammonium (TEA), the latter only when present on the side of the channel from which K+ flow originates. Macroscopic basolateral K+ conductance, determined in amphotericin-permeabilised epithelia, was also markedly reduced by quinidine and verapamil, TEA inhibited only from the lumen side, and serosal ChTX was without effect. The chromanol 293B and the sulphonylurea tolbutamide did not affect BKCa channels and had no or only a small inhibitory effect on macroscopic basolateral K+ conductance. Transepithelial Na+ absorption was partly inhibited by Ba2+, quinidine and verapamil, suggesting that BKCa channels are involved in basolateral recirculation of K+ during Na+ absorption in rabbit Colon. The BKCa channel inhibitors TEA and ChTX did not reduce Na+ absorption, probably because TEA does not enter intact cells and ChTX is ‘knocked off’ its extracellular binding site by K+ outflow from the cell interior. Transepithelial Cl− secretion was inhibited completely by Ba2+ and 293B, partly by quinidine but not by the other K+ channel blockers, indicating that the small (

  • Basolateral potassium channels of rabbit Colon Epithelium: role in sodium absorption and chloride secretion
    Biochimica et Biophysica Acta, 2002
    Co-Authors: Klaus Turnheim, Herbert Plass, Wolfgang Wyskovsky
    Abstract:

    Abstract In order to assess the role of different classes of K + channels in recirculation of K + across the basolateral membrane of rabbit distal Colon Epithelium, the effects of various K + channel inhibitors were tested on the activity of single K + channels from the basolateral membrane, on macroscopic basolateral K + conductance, and on the rate of Na + absorption and Cl − secretion. In single-channel measurements using the lipid bilayer reconstitution system, high-conductance (236 pS), Ca 2+ -activated K + (BK Ca ) channels were most frequently detected; the second most abundant channel was a low-conductance K + channel (31 pS) that exhibited channel rundown. In addition to Ba 2+ and charybdotoxin (ChTX), the BK Ca channels were inhibited by quinidine, verapamil and tetraethylammonium (TEA), the latter only when present on the side of the channel from which K + flow originates. Macroscopic basolateral K + conductance, determined in amphotericin-permeabilised epithelia, was also markedly reduced by quinidine and verapamil, TEA inhibited only from the lumen side, and serosal ChTX was without effect. The chromanol 293B and the sulphonylurea tolbutamide did not affect BK Ca channels and had no or only a small inhibitory effect on macroscopic basolateral K + conductance. Transepithelial Na + absorption was partly inhibited by Ba 2+ , quinidine and verapamil, suggesting that BK Ca channels are involved in basolateral recirculation of K + during Na + absorption in rabbit Colon. The BK Ca channel inhibitors TEA and ChTX did not reduce Na + absorption, probably because TEA does not enter intact cells and ChTX is ‘knocked off’ its extracellular binding site by K + outflow from the cell interior. Transepithelial Cl − secretion was inhibited completely by Ba 2+ and 293B, partly by quinidine but not by the other K + channel blockers, indicating that the small ( V LQT1 channels are responsible for basolateral K + exit during Cl − secretion. Hence different types of K + channels mediate basolateral K + exit during transepithelial Na + and Cl − transport.

  • membrane phospholipid composition affects function of potassium channels from rabbit Colon Epithelium
    American Journal of Physiology-cell Physiology, 1999
    Co-Authors: Klaus Turnheim, Johannes Gruber, Christoph Wachter, Valentina Ruizgutierrez
    Abstract:

    We tested the effects of membrane phospholipids on the function of high-conductance, Ca2+-activated K+ channels from the basolateral cell membrane of rabbit distal Colon Epithelium by reconstitutin...

Lars Eckmann - One of the best experts on this subject based on the ideXlab platform.

  • regulated production of the chemokine ccl28 in human Colon Epithelium
    American Journal of Physiology-gastrointestinal and Liver Physiology, 2004
    Co-Authors: Hiroyuki Ogawa, Mitsutoshi Iimura, Lars Eckmann, Martin F Kagnoff
    Abstract:

    The chemokine CCL28 is constitutively expressed by epithelial cells at several mucosal sites and is thought to function as a homeostatic chemoattractant of subpopulations of T cells and IgA B cells...

  • cell differentiation is a key determinant of cathelicidin ll 37 human cationic antimicrobial protein 18 expression by human Colon Epithelium
    Infection and Immunity, 2002
    Co-Authors: Kouji Hase, Lars Eckmann, John D Leopard, Nissi M Varki, Martin F Kagnoff
    Abstract:

    Antimicrobial peptides are highly conserved evolutionarily and are thought to play an important role in innate immunity at intestinal mucosal surfaces. To better understand the role of the antimicrobial peptide human cathelicidin LL-37/human cationic antimicrobial protein 18 (hCAP18) in intestinal mucosal defense, we characterized the regulated expression and production of this peptide by human intestinal Epithelium. LL-37/hCAP18 is shown to be expressed within epithelial cells located at the surface and upper crypts of normal human Colon. Little or no expression was seen within the deeper Colon crypts or within epithelial cells of the small intestine. Paralleling its expression in more differentiated epithelial cells in vivo, LL-37/hCAP18 mRNA and protein expression was upregulated in spontaneously differentiating Caco-2 human Colon epithelial cells and in HCA-7 human Colon epithelial cells treated with the cell differentiation-inducing agent sodium butyrate. LL-37/hCAP18 expression by Colon Epithelium does not require commensal bacteria, since LL-37/hCAP18 is produced with a similar expression pattern by epithelial cells in human Colon xenografts that lack a luminal microflora. LL-37/hCAP18 mRNA was not upregulated in response to tumor necrosis factor alpha, interleukin 1α (IL-1α), gamma interferon, lipopolysaccharide, or IL-6, nor did the expression patterns and levels of LL-37/hCAP18 in the Epithelium of the normal and inflamed Colon differ. On the other hand, infection of HCA-7 cells with Salmonella enterica serovar Dublin or enteroinvasive Escherichia coli modestly upregulated LL-37/hCAP18 mRNA expression. We conclude that differentiated human Colon Epithelium expresses LL-37/hCAP18 as part of its repertoire of innate defense molecules and that the distribution and regulated expression of LL-37/hCAP18 in the Colon differs markedly from that of other enteric antimicrobial peptides, such as defensins.

  • Cell Differentiation Is a Key Determinant of Cathelicidin LL-37/Human Cationic Antimicrobial Protein 18 Expression by Human Colon Epithelium
    Infection and Immunity, 2002
    Co-Authors: Kouji Hase, Lars Eckmann, John D Leopard, Nissi M Varki, Martin F Kagnoff
    Abstract:

    Antimicrobial peptides are highly conserved evolutionarily and are thought to play an important role in innate immunity at intestinal mucosal surfaces. To better understand the role of the antimicrobial peptide human cathelicidin LL-37/human cationic antimicrobial protein 18 (hCAP18) in intestinal mucosal defense, we characterized the regulated expression and production of this peptide by human intestinal Epithelium. LL-37/hCAP18 is shown to be expressed within epithelial cells located at the surface and upper crypts of normal human Colon. Little or no expression was seen within the deeper Colon crypts or within epithelial cells of the small intestine. Paralleling its expression in more differentiated epithelial cells in vivo, LL-37/hCAP18 mRNA and protein expression was upregulated in spontaneously differentiating Caco-2 human Colon epithelial cells and in HCA-7 human Colon epithelial cells treated with the cell differentiation-inducing agent sodium butyrate. LL-37/hCAP18 expression by Colon Epithelium does not require commensal bacteria, since LL-37/hCAP18 is produced with a similar expression pattern by epithelial cells in human Colon xenografts that lack a luminal microflora. LL-37/hCAP18 mRNA was not upregulated in response to tumor necrosis factor alpha, interleukin 1α (IL-1α), gamma interferon, lipopolysaccharide, or IL-6, nor did the expression patterns and levels of LL-37/hCAP18 in the Epithelium of the normal and inflamed Colon differ. On the other hand, infection of HCA-7 cells with Salmonella enterica serovar Dublin or enteroinvasive Escherichia coli modestly upregulated LL-37/hCAP18 mRNA expression. We conclude that differentiated human Colon Epithelium expresses LL-37/hCAP18 as part of its repertoire of innate defense molecules and that the distribution and regulated expression of LL-37/hCAP18 in the Colon differs markedly from that of other enteric antimicrobial peptides, such as defensins.

Kouji Hase - One of the best experts on this subject based on the ideXlab platform.

  • cell differentiation is a key determinant of cathelicidin ll 37 human cationic antimicrobial protein 18 expression by human Colon Epithelium
    Infection and Immunity, 2002
    Co-Authors: Kouji Hase, Lars Eckmann, John D Leopard, Nissi M Varki, Martin F Kagnoff
    Abstract:

    Antimicrobial peptides are highly conserved evolutionarily and are thought to play an important role in innate immunity at intestinal mucosal surfaces. To better understand the role of the antimicrobial peptide human cathelicidin LL-37/human cationic antimicrobial protein 18 (hCAP18) in intestinal mucosal defense, we characterized the regulated expression and production of this peptide by human intestinal Epithelium. LL-37/hCAP18 is shown to be expressed within epithelial cells located at the surface and upper crypts of normal human Colon. Little or no expression was seen within the deeper Colon crypts or within epithelial cells of the small intestine. Paralleling its expression in more differentiated epithelial cells in vivo, LL-37/hCAP18 mRNA and protein expression was upregulated in spontaneously differentiating Caco-2 human Colon epithelial cells and in HCA-7 human Colon epithelial cells treated with the cell differentiation-inducing agent sodium butyrate. LL-37/hCAP18 expression by Colon Epithelium does not require commensal bacteria, since LL-37/hCAP18 is produced with a similar expression pattern by epithelial cells in human Colon xenografts that lack a luminal microflora. LL-37/hCAP18 mRNA was not upregulated in response to tumor necrosis factor alpha, interleukin 1α (IL-1α), gamma interferon, lipopolysaccharide, or IL-6, nor did the expression patterns and levels of LL-37/hCAP18 in the Epithelium of the normal and inflamed Colon differ. On the other hand, infection of HCA-7 cells with Salmonella enterica serovar Dublin or enteroinvasive Escherichia coli modestly upregulated LL-37/hCAP18 mRNA expression. We conclude that differentiated human Colon Epithelium expresses LL-37/hCAP18 as part of its repertoire of innate defense molecules and that the distribution and regulated expression of LL-37/hCAP18 in the Colon differs markedly from that of other enteric antimicrobial peptides, such as defensins.

  • Cell Differentiation Is a Key Determinant of Cathelicidin LL-37/Human Cationic Antimicrobial Protein 18 Expression by Human Colon Epithelium
    Infection and Immunity, 2002
    Co-Authors: Kouji Hase, Lars Eckmann, John D Leopard, Nissi M Varki, Martin F Kagnoff
    Abstract:

    Antimicrobial peptides are highly conserved evolutionarily and are thought to play an important role in innate immunity at intestinal mucosal surfaces. To better understand the role of the antimicrobial peptide human cathelicidin LL-37/human cationic antimicrobial protein 18 (hCAP18) in intestinal mucosal defense, we characterized the regulated expression and production of this peptide by human intestinal Epithelium. LL-37/hCAP18 is shown to be expressed within epithelial cells located at the surface and upper crypts of normal human Colon. Little or no expression was seen within the deeper Colon crypts or within epithelial cells of the small intestine. Paralleling its expression in more differentiated epithelial cells in vivo, LL-37/hCAP18 mRNA and protein expression was upregulated in spontaneously differentiating Caco-2 human Colon epithelial cells and in HCA-7 human Colon epithelial cells treated with the cell differentiation-inducing agent sodium butyrate. LL-37/hCAP18 expression by Colon Epithelium does not require commensal bacteria, since LL-37/hCAP18 is produced with a similar expression pattern by epithelial cells in human Colon xenografts that lack a luminal microflora. LL-37/hCAP18 mRNA was not upregulated in response to tumor necrosis factor alpha, interleukin 1α (IL-1α), gamma interferon, lipopolysaccharide, or IL-6, nor did the expression patterns and levels of LL-37/hCAP18 in the Epithelium of the normal and inflamed Colon differ. On the other hand, infection of HCA-7 cells with Salmonella enterica serovar Dublin or enteroinvasive Escherichia coli modestly upregulated LL-37/hCAP18 mRNA expression. We conclude that differentiated human Colon Epithelium expresses LL-37/hCAP18 as part of its repertoire of innate defense molecules and that the distribution and regulated expression of LL-37/hCAP18 in the Colon differs markedly from that of other enteric antimicrobial peptides, such as defensins.