Treatment of AZ-521 cells with Helicobacter pylori VacA increased cyclooxygenase 2 (COX-2) mRNA in a time- and dose-dependent manner. A p38 mitogen-activated protein kinase (MAPK) inhibitor, SB203580, blocked elevation of COX-2 mRNA levels, whereas PD98059, which blocks the Erk1/2 cascade, partially suppressed the increase. Consistent with involvement of p38 MAPK, VacA-induced accumulation of C...

AIM To evaluate the frequency of Helicobacter pylori (H. pylori) CagA antibodies in H. pylori infected subjects and to identify potential histopathological and bacterial factors related to H. pylori CagA-immune response. METHODS Systematic data to H. pylori isolates, blood samples, gastric biopsies for histological and molecular analyses were available from 99 prospectively recruited subjects...

background: helicobacter pylori (h. pylori) cytotoxin and its heterogeneity amongst strains has been closely linked to the varying infection-associated clinical outcomes. in order to determine the decisive role of the vacuolating cytotoxin (vaca) gene mosaicism in its corresponding gene expression and phenotype, we aimed to characterize vaca alleles of different h. pylori strains in addition to...

Helicobacter pylori VacA is a secreted toxin that induces multiple structural and functional alterations in eukaryotic cells. Exposure of VacA to either acidic or alkaline pH ('activation') results in structural changes in the protein and a marked enhancement of its cell-vacuolating activity. However, the mechanism by which activation leads to increased cytotoxicity is not well understood. In t...

The vacuolating cytotoxin and the cytotoxin-associated protein, encoded by vacA and cagA, respectively, are important virulence determinants of Helicobacter pylori. Sixty-five H. pylori strains were isolated from dyspeptic patients (19 with peptic ulcer disease, 43 with chronic gastritis, and 3 with gastric cancer) and studied for differences in the vacA and cagA genes and their relationship to...

helicobacter pylori has been strongly associated with peptic ulcer diseases, chronic gastritis, ulcers, and reported as a risk factor for gastric cancer, too. the vaculating cytotoxin (vaca), the cytotoxin associated genes (caga), the induced by contact with epithelium factor antigen (icea gene), blood adhesion binding antigen (baba2), and outer membrane protein oipa have been described as diff...

BACKGROUND The cag pathogenicity island includes a number of genes, including cytotoxin-associated protein A (cagA) and vacuolating cytotoxin (vacA) genotypes, which are associated with bacterial virulence. Although the role of cagA and vacA in the virulence of Helicobacter pylori (H. pylori) is well-established in epidemiological studies, the relationship between the cagA and vacA genotypes in...

Helicobacter pylori vacuolating toxin (VacA) causes vacuolation in a variety of cultured cell lines, sensitivity to VacA differing greatly, however, among the different cell types. We found that the high sensitivity of HEp-2 cells to VacA was impaired by treating the cells with phosphatidylinositol-specific phospholipase C (PI-PLC) which removes glycosylphosphatidylinositol (GPI)-anchored prote...

Anthocyanins have been studied as potential antimicrobial agents against Helicobacter pylori. We investigated whether the biosynthesis and secretion of cytotoxin-associated protein A (CagA) and vacuolating cytotoxin A (VacA) could be suppressed by anthocyanin treatment in vitro. H. pylori reference strain 60190 (CagA(+)/VacA(+)) was used in this study to investigate the inhibitory effects of an...

BACKGROUND The vacuolating cytotoxin and the cytotoxinassociated protein, encoded by vacA and cagA, respectively, are important virulence determinants of Helicobacter pylori. OBJECTIVE The aim of this study was to perform vacA genotyping and evaluate its association with cagA genotype and clinical outcome. METHODS One hundred and twenty H. pylori strains were isolated from dyspeptic patient...