BACKGROUND VacA and CagA proteins have been reported to be major virulence factors of Helicobacter pylori. However, antibodies against these proteins are frequently found in the sera of Japanese patients regardless of their gastroduodenal status. AIM To evaluate the expression of VacA and CagA proteins by H pylori strains isolated in Japan. METHODS By using specific antibodies raised agains...

Introduction: In the recent decades, a number of studies have highlighted the importance of Helicobacter pylori in the initiation and development of peptic ulcer and gastric cancer. Some potential virulence factors (e.g., urease, CagA, VacA, BabA) are exploited by this microorganism, facilitating its persistence through evading human defense mechanisms. Among these toxins and enzymes, vacuolati...

Cells exposed to Helicobacter pylori toxin VacA develop large vacuoles which originate from massive swelling of membranous compartments at late stages of the endocytic pathway. When expressed in the cytosol, VacA induces vacuolization as it does when added from outside. This and other evidence indicate that VacA is a toxin capable of entering the cell cytosol, where it displays its activity. In...

BACKGROUND Helicobacter pylori is a pathogenic bacterium that causes various gastrointestinal diseases. The most common gastric malignancies associated with H. pylori are gastric cancer and lymphoma of mucosa associated lymphoid tissue (MALT). Helicobacter pylori virulence genes, namely cagA and vacA, are known to be associated with malignancy development. Conventionally, cagA and vacA were cla...

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—Virulence factors of Helicobacter pylori are associated with peptic ulcer disease and may be also associated with the eYcacy of treatment. Aims—To determine the relation between the vacA and the cagA status of H pylori, clinical disease, and treatment outcome. Patients—121 patients with H pylori infection and peptic ulcer disease or functional dyspepsia were treated by quadruple anti...

BACKGROUND The recombinant vacuolating cytotoxin (rVacA) of Helicobacter pylori that retains native conformational epitopes was evaluated as a vaccine antigen for anti-H. pylori treatment. METHODS s1m1 vacA gene fraction encoding the mature VacA protein was expressed as a soluble protein in E. coli at low temperature. The efficacy of anti-rVacA antibody against VacA or H. pylori was assessed ...

Helicobacter pylori induces cell death by apoptosis. However, the apoptosis-inducing factor is still unknown. The virulence factor vacuolating cytotoxin A (VacA) is a potential candidate, and thus its role in apoptosis induction was investigated in the human gastric epithelial cell line AGS. The supernatant from the vacA wild-type strain P12 was able to induce apoptotic cell death, whereas the ...

AIM To examine the vacA genotypes of Helicobacter pylori strains in Japan and to define whether any specific genotype was associated with gastric cancer. METHODS The allelic variation of vacA gene was studied using a recently introduced polymerase chain reaction based vacA genotyping system. RESULTS 80 H pylori strains were isolated from gastric biopsies of 40 patients with gastric cancer a...

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...