scholarly journals Helicobacter pyloriOuter Membrane Vesicle Proteins Induce Human Eosinophil Degranulation via aβ2 Integrin CD11/CD18- and ICAM-1-Dependent Mechanism

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Su Hyuk Ko ◽  
Jong Ik Jeon ◽  
Young-Jeon Kim ◽  
Ho Joo Yoon ◽  
Hyeyoung Kim ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Inflammatory Responses ◽  
Membrane Vesicle ◽  
Eosinophil Cationic Protein ◽  
Outer Membrane Vesicles ◽  
Gastric Epithelial Cells ◽  
Cationic Protein ◽  
Human Eosinophil ◽  
H Pylori ◽  
Eosinophil Degranulation

Eosinophil cationic protein (ECP), a cytotoxic protein contained in eosinophils granules, can contribute to various inflammatory responses. AlthoughHelicobacter pyloriinfection increases infiltration of eosinophils, the mechanisms of eosinophil degranulation byH. pyloriinfection are largely unknown. The goal of this study was to investigate the role ofH. pyloriouter membrane vesicles (OMVs) in modulating eosinophil degranulation. We found that eosinophils treated withH. pyloriOMVs released significantly more ECP compared with untreated controls. In addition, eosinophils cocultured with OMV-preexposed primary gastric epithelial cells exhibited significantly increased ECP release. Similarly, eosinophils cocultured with culture supernatant (CM) from primary gastric epithelial cells exposed to OMVs (OMV-CM) released significantly higher amounts of ECP compared with eosinophils cocultured with CM from unexposed control cells. Furthermore, OMVs and OMV-CM both induced the upregulation of ICAM-1 on gastric epithelial cells andβ2 integrin CD11b on eosinophils. In addition, both transduction ofICAM-1shRNA into gastric epithelial cells and treatment with neutralizing mAbs to CD18 significantly decreased OMV-mediated or OMV-CM-mediated release of ECP. These results suggest that the eosinophil degranulation response toH. pyloriOMVs occurs via a mechanism that is dependent on bothβ2 integrin CD11/CD18 and ICAM-1.

scholarly journals Helicobacter pylori Binds to CD74 on Gastric Epithelial Cells and Stimulates Interleukin-8 Production

2005 ◽  
Vol 73 (5) ◽  
pp. 2736-2743 ◽  
Author(s):  
Ellen J. Beswick ◽  
David A. Bland ◽  
Giovanni Suarez ◽  
Carlos A. Barrera ◽  
Xuejung Fan ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Epithelial Cells ◽  
Inflammatory Responses ◽  
Surface Expression ◽  
Class Ii ◽  
Gastric Epithelium ◽  
Host Responses ◽  
Gastric Epithelial Cells ◽  
Class Ii Mhc ◽  
H Pylori

ABSTRACT The pathogenesis associated with Helicobacter pylori infection requires consistent contact with the gastric epithelium. Although several cell surface receptors have been suggested to play a role in adhesion, the bacterium-host interactions that elicit host responses are not well defined. This study investigated the interaction of H. pylori with the class II major histocompatibility complex (MHC)-associated invariant chain (Ii; CD74), which was found to be highly expressed by gastric epithelial cells. Bacterial binding was increased when CD74 surface expression was increased by gamma interferon (IFN-γ) treatment or by fibroblast cells transfected with CD74, while binding was decreased by CD74 blocking antibodies, enzyme cleavage of CD74, and CD74-coated bacteria. H. pylori was also shown to bind directly to affinity-purified CD74 in the absence of class II MHC. Cross-linking of CD74 and the engagement of CD74 were verified to stimulate IL-8 production by unrelated cell lines expressing CD74 in the absence of class II MHC. Increased CD74 expression by cells increased IL-8 production in response to H. pylori, and agents that block CD74 decreased these responses. The binding of H. pylori to CD74 presents a novel insight into an initial interaction of H. pylori with the gastric epithelium that leads to upregulation of inflammatory responses.

scholarly journals Helicobacter pylori Outer Membrane Vesicles Modulate Proliferation and Interleukin-8 Production by Gastric Epithelial Cells

2003 ◽  
Vol 71 (10) ◽  
pp. 5670-5675 ◽  
Author(s):  
Salim Ismail ◽  
Mark B. Hampton ◽  
Jacqueline I. Keenan
Keyword(s):  
Helicobacter Pylori ◽  
Epithelial Cells ◽  
Outer Membrane ◽  
Strain Differences ◽  
Membrane Vesicles ◽  
Outer Membrane Vesicles ◽  
Interleukin 8 ◽  
Low Grade ◽  
Gastric Epithelial Cells ◽  
H Pylori

ABSTRACT Helicobacter pylori infection, which is always associated with gastritis, can progress to ulceration or malignancy. The diversity in clinical outcomes is partly attributed to the expression of virulence factors and adhesins by H. pylori. However, H. pylori may not have to adhere to the epithelium to cause gastritis. We hypothesize that outer membrane vesicles (OMV), which are constantly shed from the surface of H. pylori, play a role as independent activators of host cell responses. In this study, we found that low doses of OMV from cag PAI+ toxigenic and cag PAI− nontoxigenic strains increased proliferation of AGS gastric epithelial cells. At higher doses, we detected growth arrest, increased toxicity, and interleukin-8 (IL-8) production. The only strain differences detected were vacuolation with the toxigenic strain and higher levels of IL-8 production with OMV from the cag PAI− nontoxigenic strain. In summary, we suggest that constitutively shed OMV play a role in promoting the low-grade gastritis associated with H. pylori infection.

scholarly journals Uptake of Helicobacter pylori Outer Membrane Vesicles by Gastric Epithelial Cells

2010 ◽  
Vol 78 (12) ◽  
pp. 5054-5061 ◽  
Author(s):  
Heather Parker ◽  
Kenny Chitcholtan ◽  
Mark B. Hampton ◽  
Jacqueline I. Keenan
Keyword(s):  
Helicobacter Pylori ◽  
Epithelial Cells ◽  
Outer Membrane ◽  
Mutant Strain ◽  
Membrane Vesicles ◽  
Human Stomach ◽  
Outer Membrane Vesicles ◽  
Gastric Epithelial Cells ◽  
Isogenic Mutant Strain ◽  
H Pylori

ABSTRACT Helicobacter pylori bacteria colonize the human stomach where they stimulate a persistent inflammatory response. H. pylori is considered noninvasive; however, lipopolysaccharide (LPS)-enriched outer membrane vesicles (OMV), continuously shed from the surface of this bacterium, are observed within gastric epithelial cells. The mechanism of vesicle uptake is poorly understood, and this study was undertaken to examine the roles of bacterial VacA cytotoxin and LPS in OMV binding and cholesterol and clathrin-mediated endocytosis in vesicle uptake by gastric epithelial cells. OMV association was examined using a fluorescent membrane dye to label OMV, and a comparison was made between the associations of vesicles from a VacA+ strain and OMV from a VacA− isogenic mutant strain. Within 20 min, essentially all associated OMV were intracellular, and vesicle binding appeared to be facilitated by the presence of VacA cytotoxin. Uptake of vesicles from the VacA+ strain was inhibited by H. pylori LPS (58% inhibition with 50 μg/ml LPS), while uptake of OMV from the VacA− mutant strain was less affected (25% inhibition with 50 μg/ml LPS). Vesicle uptake did not require cholesterol. However, uptake of OMV from the VacA− mutant strain was inhibited by a reduction in clathrin-mediated endocytosis (42% with 15 μg/ml chlorpromazine), while uptake of OMV from the VacA+ strain was less affected (25% inhibition with 15 μg/ml chlorpromazine). We conclude that VacA toxin enhances the association of H. pylori OMV with cells and that the presence of the toxin may allow vesicles to exploit more than one pathway of internalization.

Effect of H. pylori on the expression of TRAIL receptor subtypes and apoptosis in human gastric epithelial cells

2001 ◽  
Vol 120 (5) ◽  
pp. A81-A81
Author(s):  
J MARTIN ◽  
A POTTHOFF ◽  
M COMBERG ◽  
I SOBEKKLOCKE ◽  
S LEDIG ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Receptor Subtypes ◽  
Trail Receptor ◽  
Gastric Epithelial Cells ◽  
H Pylori

scholarly journals Rabeprazole inhibits inflammatory reaction by inhibition of cell pyroptosis in gastric epithelial cells

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Jing Xie ◽  
Long Fan ◽  
Liya Xiong ◽  
Peiyu Chen ◽  
Hongli Wang ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Clinical Sample ◽  
Critical Role ◽  
Enzyme Linked Immunosorbent Assay ◽  
Inflammasome Activation ◽  
Peptic Ulcers ◽  
Gastric Epithelial Cells ◽  
Caspase 1 ◽  
H Pylori

Abstract Background Helicobacter pylori (H. pylori) is a common pathogen in development of peptic ulcers with pyroptosis. Rabeprazole, a critical component of standard triple therapy, has been widely used as the first-line regimen for H. pylori infectious treatment. The aim of this study to explore the function of Rabeprazole on cell pyroptosis in vitro. Methods The clinical sample from patients diagnosed with or without H. pylori-infection were collected to analyze by Immunohistochemistry (IHC). Real-time quantitative PCR (qPCR), western blot (WB) and enzyme linked immunosorbent assay (Elisa) were performed to analyze the effect of Rabeprazole on cell pyroptosis, including LDH, IL-1β and IL-18. Results In this study, we showed that Rabeprazole regulated a phenomenon of cell pyroptosis as confirmed by lactate dehydrogenase (LDH) assay. Further results showed that Rabeprazole inhibited cell pyroptosis in gastric epithelial cells by alleviating GSDMD-executed pyroptosis, leading to decrease IL-1β and IL-18 mature and secretion, which is attributed to NLRP3 inflammasome activation inhibition. Further analysis showed that ASC, NLRP3 and Caspase-1, was significantly repressed in response to Rabeprazole stimulation, resulting in decreasing cleaved-caspase-1 expression. Most important, NLRP3 and GSDMD is significantly increased in gastric tissue of patients with H. pylori infection. Conclusion These findings revealed a critical role of Rabeprazole in cell pyroptosis in patients with H. pylori infection, suggesting that targeting cell pyroptosis is an alternative strategy in improving H. pylori treatment.

scholarly journals Human eosinophil cationic protein. Molecular cloning of a cytotoxin and helminthotoxin with ribonuclease activity.

1989 ◽  
Vol 170 (1) ◽  
pp. 163-176 ◽  
Author(s):  
H F Rosenberg ◽  
S J Ackerman ◽  
D G Tenen
Keyword(s):  
Amino Acid ◽  
Cellular Localization ◽  
Basic Protein ◽  
Eosinophil Cationic Protein ◽  
Ribonuclease Activity ◽  
Monocytic Differentiation ◽  
Cationic Protein ◽  
Human Eosinophil ◽  
Reading Frame ◽  
The Matrix

We have isolated a 725-bp full-length cDNA clone for the human eosinophil cationic protein (ECP). ECP is a small, basic protein found in the matrix of the eosinophil's large specific granule that has cytotoxic, helminthotoxic, and ribonuclease activity, and is a member of the ribonuclease multigene family. The cDNA sequence shows 89% sequence identity with that reported for the related granule protein, eosinophil-derived neurotoxin (EDN). The open reading frame encodes a previously unidentified 27-amino acid leader sequence preceding a 133-residue mature ECP polypeptide with a molecular mass of 15.6 kD. The encoded amino acid sequence of ECP shows 66% identity to that of EDN and 31% identity to that of human pancreatic ribonuclease, including conservation of the essential structural cysteine and cataytic lysine and histidine residues. mRNA for ECP was detected in eosinophil-enriched peripheral granulocytes and in a subclone of the promyelocytic leukemia line, HL-60, induced toward eosinophilic differentiation with IL-5. No ECP mRNA was detected in uninduced HL-60 cells, or in HL-60 cells induced toward monocytic differentiation with vitamin D3 or toward neutrophilic differentiation with DMSO. In contrast, mRNA for EDN was detected in uninduced HL-60 cells and was upregulated in HL-60 cells induced with DMSO. Despite similarities in sequence and cellular localization, these results suggest that ECP and EDN are subject to different regulatory mechanisms.

scholarly journals Effects ofHelicobacter pyloriand Heat Shock Protein 70 on the Proliferation of Human Gastric Epithelial Cells

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Liping Tao ◽  
Hai Zou ◽  
Zhimin Huang
Keyword(s):  
Helicobacter Pylori ◽  
Heat Shock ◽  
Epithelial Cells ◽  
Heat Shock Protein ◽  
Mtt Assay ◽  
Heat Shock Protein 70 ◽  
Hsp70 Expression ◽  
Gastric Epithelial Cells ◽  
Ags Cells ◽  
H Pylori

Infection ofHelicobacter pylori (H. pylori)changed the proliferation of gastric epithelial cells and decreased the expression of heat shock protein 70 (HSP70). However, the effects ofH. pylorion the proliferation of gastric epithelial cells and the roles of HSP70 during the progress need further investigation.Objective.To investigate the effects ofHelicobacter pylori (H. pylori)and heat shock protein 70 (HSP70) on the proliferation of human gastric epithelial cells.Methods. H. pyloriand a human gastric epithelial cell line (AGS) were cocultured. The proliferation of AGS cells was quantitated by an MTT assay, and the expression of HSP70 in AGS cells was detected by Western blotting. HSP70 expression in AGS cells was silenced by small interfering RNA (siRNA) to investigate the role of HSP70. ThesiRNA-treated AGS cells were cocultured withH. pyloriand cell proliferation was measured by an MTT assay.Results.The proliferation of AGS cells was accelerated by coculturing withH. pylorifor 4 and 8 h, but was suppressed at 24 and 48 h. HSP70 expression was decreased in AGS cells infected byH. pylorifor 48 h. The proliferation in HSP70-silenced AGS cells was inhibited after coculturing withH. pylorifor 24 and 48 h compared with the control group.Conclusions.Coculture ofH. pylorialtered the proliferation of gastric epithelial cells and decreased HSP70 expression. HSP70 knockdown supplemented the inhibitory effect ofH. pylorion proliferation of epithelial cells. These results indicate that the effects ofH. pylorion the proliferation of gastric epithelial cells at least partially depend on the decreased expression of HSP70 induced by the bacterium.

scholarly journals Suppression of IL-8 production in gastric epithelial cells by MUC1 mucin and peroxisome proliferator-associated receptor-γ

2012 ◽  
Vol 303 (6) ◽  
pp. G765-G774 ◽  
Author(s):  
Yong Sung Park ◽  
Wei Guang ◽  
Thomas G. Blanchard ◽  
K. Chul Kim ◽  
Erik P. Lillehoj
Keyword(s):  
Epithelial Cells ◽  
Negative Control ◽  
Luciferase Reporter ◽  
Peroxisome Proliferator ◽  
Apical Surface ◽  
Gastric Epithelial Cells ◽  
Luciferase Reporter Gene ◽  
Ags Cells ◽  
Pparγ Agonist ◽  
H Pylori

MUC1 is a membrane-tethered mucin expressed on the apical surface of epithelial cells. Our previous report (Guang W, Ding H, Czinn SJ, Kim KC, Blanchard TG, Lillehoj EP. J Biol Chem 285: 20547–20557, 2010) demonstrated that expression of MUC1 in AGS gastric epithelial cells limits Helicobacter pylori infection and reduces bacterial-driven IL-8 production. In this study, we identified the peroxisome proliferator-associated receptor-γ (PPARγ) upstream of MUC1 in the anti-inflammatory pathway suppressing H. pylori- and phorbol 12-myristate 13-acetate (PMA)-stimulated IL-8 production. Treatment of AGS cells with H. pylori or PMA increased IL-8 levels in cell culture supernatants compared with cells treated with the respective vehicle controls. Prior small interfering (si)RNA-induced MUC1 silencing further increased H. pylori - and PMA-stimulated IL-8 levels compared with a negative control siRNA. MUC1-expressing AGS cells pretreated with the PPARγ agonist troglitazone (TGN) had reduced H. pylori - and PMA-stimulated IL-8 levels compared with cells treated with H. pylori or PMA alone. However, following MUC1 siRNA knockdown, no differences in IL-8 levels were seen between TGN/ H. pylori and H. pylori -only cells or between TGN/PMA and PMA-only cells. Finally, TGN-treated AGS cells had increased Muc1 promoter activity, as measured using a Muc1-luciferase reporter gene, and greater MUC1 protein levels by Western blot analysis, compared with vehicle controls. These results support the hypothesis that PPARγ stimulates MUC1 expression by AGS cells, thereby attenuating H. pylori - and PMA-induced IL-8 production.

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