scholarly journals E. coli Enterotoxin LtB Enhances Vaccine-Induced Anti-H. pylori Protection by Promoting Leukocyte Migration into Gastric Mucus via Inflammatory Lesions

Cells ◽  
2019 ◽  
Vol 8 (9) ◽  
pp. 982
Author(s):  
Xiaoyan Peng ◽  
Rongguang Zhang ◽  
Chen Wang ◽  
Feiyan Yu ◽  
Mingyang Yu ◽  
...  
Keyword(s):  
Cellular Immunity ◽  
Protective Efficacy ◽  
Gastric Injury ◽  
Oral Vaccines ◽  
Gastric Mucus ◽  
E Coli ◽  
Non Invasive ◽  
Considerable Impact ◽  
H Pylori

Current studies indicate that the anti-H. pylori protective efficacy of oral vaccines to a large extent depends on using mucosal adjuvants like E. coli heat-lable enterotoxin B unit (LtB). However, the mechanism by which Th17/Th1-driven cellular immunity kills H. pylori and the role of LtB remains unclear. Here, two L. lactis strains, expressing H. pylori NapA and LtB, respectively, were orally administrated to mice. As observed, the administration of LtB significantly enhanced the fecal SIgA level and decreased gastric H. pylori colonization, but also markedly aggravated gastric inflammatory injury. Both NapA group and NapA+LtB group had elevated splenocyte production of IL-8, IL-10, IL-12, IL-17, IL-23 and INF-γ. Notably, gastric leukocytes’ migration or leakage into the mucus was observed more frequently in NapA+LtB group than in NapA group. This report is the first that discusses how LtB enhances vaccine-induced anti-H. pylori efficacy by aggravating gastric injury and leukocytes’ movement into the mucus layer. Significantly, it brings up a novel explanation for the mechanism underlying mucosal cellular immunity destroying the non-invasive pathogens. More importantly, the findings suggest the necessity to further evaluate LtB’s potential hazards to humans before extending its applications. Thus, this report can provide considerable impact on the fields of mucosal immunology and vaccinology.

Metallothionein is a crucial protective factor againstHelicobacter pylori-induced gastric erosive lesions in a mouse model

2008 ◽  
Vol 294 (4) ◽  
pp. G877-G884 ◽  
Author(s):  
Masaharu Mita ◽  
Masahiko Satoh ◽  
Akinori Shimada ◽  
Mina Okajima ◽  
Sadahiro Azuma ◽  
...  
Keyword(s):  
Metal Binding ◽  
Protective Factor ◽  
Histopathological Examination ◽  
Inflammatory Cells ◽  
Gastric Injury ◽  
Wild Type ◽  
Inflammatory Protein ◽  
Ros Scavenger ◽  
H Pylori

Infection with the gastric pathogen Helicobacter pylori ( H. pylori) causes chronic gastritis, peptic ulcer, and gastric adenocarcinoma. These diseases are associated with production of reactive oxygen species (ROS) from infiltrated macrophages and neutrophiles in inflammatory sites. Metallothionein (MT) is a low-molecular-weight, cysteine-rich protein that can act not only as a metal-binding protein, but also as a ROS scavenger. In the present study, we examined the role of MT in the protection against H. pylori-induced gastric injury using MT-null mice. Female MT-null and wild-type mice were challenged with H. pylori SS1 strain, and then histological changes were evaluated with the updated Sydney grading system at 17 and 21 wk after challenge. Although the colonization efficiency of H. pylori was essentially the same for MT-null and wild-type mice, the scores of activity of inflammatory cells were significantly higher in MT-null mice than in wild-type mice at 17 wk after challenge. Histopathological examination revealed erosive lesions accompanied by infiltration of inflammatory cells in the infected MT-null mice but not in wild-type mice. Furthermore, activation of NF-κB and expression of NF-κB-mediated chemokines such as macrophage inflammatory protein-1α and monocytes chemoattractant protein-1 in gastric cells were markedly higher in MT-null mice than in wild-type mice. These results suggest that MT in the gastric mucosa might play an important role in the protection against H. pylori-induced gastric ulceration.

scholarly journals Crystal structures of γ-glutamyltranspeptidase in complex with inhibitors

2014 ◽  
Vol 70 (a1) ◽  
pp. C847-C847
Author(s):  
Kei Hirabayashi ◽  
Tomoyo Ida ◽  
Chunjie Li ◽  
Hideyuki Suzuki ◽  
Keiichi Fukuyama ◽  
...  
Keyword(s):  
Crystal Structures ◽  
Cellular Response ◽  
Physiological Role ◽  
Time Lapse ◽  
Binding Mode ◽  
E Coli ◽  
Glutathione Biosynthesis ◽  
Intracellular Glutathione ◽  
H Pylori

γ-Glutamyltranspeptidase (GGT; EC 2.3.2.2) is involved in the degradation of γ-glutamyl compounds such as glutathione (GSH; γ-glutamyl-cysteinyl-glycine) . A major physiological role of this enzyme is to cleave the extracellular GSH as a source of cysteine for intracellular glutathione biosynthesis. Another crucial role of GGT is to cleave glutathione-S-conjugates as a key step in detoxification of xenobiotics and drug metabolism. In mammals, GGT has been implicated in physiological disorders such as Parkinson's disease, other neurodegenerative diseases including Alzheimer's disease and cardiovascular disease. The indispensable roles played by GGT in GSH-mediated detoxification and cellular response to oxidative stress suggest that GGT is an attractive pharmaceutical target. We here report the binding mode of acivicin, a well-known glutamine antagonist, to B. subtilis GGT at 1.8 Å resolution showing that acivicin is bound to the Oγ atom of Thr403, the catalytic nucleophile of the enzyme, through its C3 atom [1]. The observed electron density around the C3 atom was best fitted to the planar and sp2 hybridized carbon, consistent with a simple nucleophilic substitution of Cl at the imino carbon by Oγ atom of Thr403. Furthermore, comparison of three bacterial enzymes, the GGTs from E. coli, H. pylori and B. subtilis in complex with acivicin, showed significant diversity in the orientation of the dihydroisoxazole ring among three GGTs. The differences are discussed in terms of the recognition of the α-amino and α-carboxy groups in preference to the dihydroisoxazole ring as observed in time-lapse soaking crystal structures of B. subtilis GGT with acivicin.

scholarly journals Galectin-2 Has Bactericidal Effects against Helicobacter pylori in a β-galactoside-Dependent Manner

2020 ◽  
Vol 21 (8) ◽  
pp. 2697 ◽  
Author(s):  
Takaharu Sasaki ◽  
Rei Saito ◽  
Midori Oyama ◽  
Tomoharu Takeuchi ◽  
Toru Tanaka ◽  
...  
Keyword(s):  
Helicobacter Pylori ◽  
Bactericidal Effect ◽  
Dependent Manner ◽  
Peptic Ulcers ◽  
Gastric Tissue ◽  
Gastric Mucus ◽  
Biological Phenomena ◽  
Bactericidal Effects ◽  
H Pylori

Helicobacter pylori is associated with the onset of gastritis, peptic ulcers, and gastric cancer. Galectins are a family of β-galactoside-binding proteins involved in diverse biological phenomena. Galectin-2 (Gal-2), a member of the galectin family, is predominantly expressed in the gastrointestinal tract. Although some galectin family proteins are involved in immunoreaction, the role of Gal-2 against H. pylori infection remains unclear. In this study, the effects of Gal-2 on H. pylori morphology and survival were examined. Gal-2 induced H. pylori aggregation depending on β-galactoside and demonstrated a bactericidal effect. Immunohistochemical staining of the gastric tissue indicated that Gal-2 existed in the gastric mucus, as well as mucosa. These results suggested that Gal-2 plays a role in innate immunity against H. pylori infection in gastric mucus.

scholarly journals The morphology of the mucous membrane of the stomach at the its contamination of helicobacter, cryptosporidium and fungi of the species Candida in patients with irritable bowel syndrome

2017 ◽  
Vol 25 (1) ◽  
pp. 15-19
Author(s):  
Ivan Shcherbakov ◽  
Nina Leontieva ◽  
Nina Gracheva ◽  
V S Filippov ◽  
N A Vinogradov ◽  
...  
Keyword(s):  
Irritable Bowel Syndrome ◽  
Mucous Membrane ◽  
Life Forms ◽  
Pathological Changes ◽  
Stomach Mucosa ◽  
Non Invasive ◽  
Leading Role ◽  
H Pylori ◽  
Irritable Bowel

It is recognized the leading role of H. Pylori in the aetiology and pathogenesis of diseases of the gastrointestinal tract, it is established morphological features of changes in the mucosa at mono-infection. However, lesions of the stomach may have mixed infectious character, changing the course of the main disease. The aim of the research is to investigate the statement of the mucous membrane in its contamination with H. Pylori, Fungi of the species Candida, cryptosporidium in patients with irritable bowel syndrome. Biopsies of the mucous membrane of different stomach parts were studied, using conventional methods of dyeing with further evaluation of the results. Pathological changes in the stomach mucosa were depended on the localization of the process, the measure of contamination, and the presence of various life forms of pyloric Helicobacter whereas cryptosporidium and fungi of the species Candida (non-invasive form) did not influence essentially.

scholarly journals Gastric Mucus Alterations Associated With Murine Helicobacter Infection

2009 ◽  
Vol 57 (5) ◽  
pp. 457-467 ◽  
Author(s):  
Julia M. Schmitz ◽  
Carolyn G. Durham ◽  
Samuel B. Ho ◽  
Robin G. Lorenz
Keyword(s):  
Adaptive Immune Response ◽  
The Body ◽  
Gastric Mucus ◽  
Helicobacter Felis ◽  
Adaptive Immune ◽  
Mucous Metaplasia ◽  
Mucin Expression ◽  
Rag 1 ◽  
H Pylori

The C57BL/6 mouse has been shown to develop gastric adenocarcinoma after Helicobacter felis infection. This model was used to determine whether mucin and trefoil factor (TFF) expression after infection was altered in a similar fashion to the changes seen in the protective gastric mucus layer of the human stomach after H. pylori infection. Our results indicate that this mouse model mimics many of the changes seen after human H. pylori infection, including increased expression of muc4 and muc5b and loss of muc5ac. These alterations in mucin expression occurred as early as 4 weeks postinfection, before the development of significant mucous metaplasia or gastric dysplasia. The decrease in muc5ac expression occurred only in the body of the stomach and was not secondary to the adaptive immune response to infection, because a similar decrease in expression was seen after infection of B6.Rag-1−/− mice, which lack B and T cells. Intriguingly, the increased expression of Muc4 and Muc5b in infected C57BL/6 mice was not seen in the infected B6.Rag-1−/− mice. Because B6.Rag-1−/− mice do not develop gastric pathology after H. felis infection, these findings point to the potential role of Muc4 and Muc5b in disease progression. This manuscript contains online supplemental material at http://www.jhc.org . Please visit this article online to view these materials. (J Histochem Cytochem 57:457–467, 2009)

European multicentre validation trial of two new non-invasive tests for detection of antibody to H. pylori: Urine-based ELISA and rapid urine test

2001 ◽  
Vol 120 (5) ◽  
pp. A491-A491 ◽  
Author(s):  
A LEODOLTER ◽  
D VAIRA ◽  
F BAZZOLL ◽  
A HIRSCHL ◽  
F MEGRAUD ◽  
...  
Keyword(s):  
Urine Test ◽  
Non Invasive ◽  
H Pylori

Role of SOD in the protection of Rhizophora mangle on gastric injury induced by ethanol, ischaemia-reperfusion and acetic acid in rats

Planta Medica ◽  
2009 ◽  
Vol 75 (09) ◽  
Author(s):  
FM de-Faria ◽  
A Luiz-Ferreira ◽  
ACA Almeida ◽  
V Barbastefano ◽  
MA Silva ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Rhizophora Mangle ◽  
Gastric Injury ◽  
Ischaemia Reperfusion

The Local Sanarelli-Shwartzman Phenomenon in Rats Induced by Human Leukaemic Cells

1973 ◽  
Vol 29 (02) ◽  
pp. 353-362
Author(s):  
J Lisiewicz ◽  
A Pituch ◽  
J. A Litwin
Keyword(s):  
Chronic Lymphocytic Leukaemia ◽  
Intravenous Injection ◽  
Peripheral Blood ◽  
Lymphocytic Leukaemia ◽  
Acute Myeloblastic Leukaemia ◽  
Demarcation Line ◽  
E Coli ◽  
Leukaemic Cells ◽  
Shwartzman Phenomenon

SummaryThe local Sanarelli-Shwartzman phenomenon (SSP-L) in the skin of 30 rats was induced by an intr a cutaneous sensitizing injection of leukaemic leucocytes isolated from the peripheral blood of patients with chronic lymphocytic leukaemia (CLL), acute myeloblastic leukaemia (AL) and chronic granulocytic leukaemia (CGL) and challenged by an intravenous injection of 100(μ of E. coli endotoxin. SSP-L was observed in 7 rats after injection of CLL lymphocytes and in 6 and 2 rats after AL myeloblasts and the CGL granulocytes, respectively. The lesions in the skin after AL myeloblasts appeared in a shorter time and were of longer duration compared with those observed after CLL lymphocytes and CGL granulocytes. Histologically, the lesions consisted of areas of destruction in the superficial layers of the skin ; the demarcation line showed the presence of neutrophils, macrophages and erythrocytes. Haemorrhages and fibrin deposits near the demarcation line were larger after injection of CLL lymphocytes and AL myeloblasts than after CGL granulocytes. The possible role of leucocyte procoagulative substances in the differences observed have been discussed.

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