Helicobacter pylori cagA-positive strain delivers the CagA oncoprotein into gastric epithelial cells and at the same time elicits stomach inflammation. To experimentally investigate the pathophysiological interplay between CagA and inflammation, transgenic mice systemically expressing the bacterial cagA gene were treated with a colitis inducer, dextran sulfate sodium (DSS). Compared with contro...

Infection with CagA-positive Helicobacter pylori is associated with the development of gastric adenocarcinoma. The CagA gene product CagA is injected directly from the bacterium into the bacterium-attached gastric epithelial cells via the type-IV secretion system. Upon membrane localization and subsequent tyrosine phosphorylation by Src family kinases, CagA functions as a scaffolding adaptor an...

BACKGROUND Helicobacter pylori infection is a risk factor for the development of gastric cancer, and the bacterial oncoprotein CagA contributes to gastric carcinogenesis. METHODS We analyzed H. pylori isolates from persons in Colombia and observed that there was marked variation among strains in levels of CagA expression. To elucidate the basis for this variation, we analyzed sequences upstre...

OBJECTIVE To investigate whether the presence of structured CagA proteins in Western- and Eastern-type Helicobacter pylori (H. pylori) induces different incidences of gastric diseases. METHODS CagA and phosphorylated CagA were expressed in AGS gastric epithelial cells infected with wild type and mutant strains. The ability of individual CagA was determined by immunoprecipitation and Western b...

INTRODUCTION: Costa Rica has among the highest mortality rates from gastric cancer in world, largely due to late detection. It is therefore important that economically and logistically sustainable screening implemented order detect risk of developing cancer. We have previously shown low pepsinogen (PG) values infection with Helicobacter pylori-CagA+ are associated atrophy Rican populations. OBJ...

BACKGROUND Infection with Helicobacter pylori is a major risk factor for the development of atrophic gastritis and gastric cancer. H. pylori strains can differ with respect to the presence of cagA (cytotoxin-associated gene A), a gene encoding a high-molecular-weight immunodominant antigen. H. pylori strains possessing cagA have been associated with enhanced induction of acute gastric inflammat...

Heterogeneity at the Helicobacter pylori cagA gene promoter region has been linked to variation in CagA expression and gastric histopathology. Here, we characterized the cagA promoter and expression in 46 H. pylori strains from Portugal. Our results confirm the relationship between cagA promoter region variation and protein expression originally observed in strains from Colombia. We observed th...

Many Helicobacterpylori strains causing gastroduodenal diseases have a cagA gene encoding CagA protein, a virulence factor of these bacteria. Anti-CagA antibodies produced by the majority of people infected with CagA(+) strains can indicate such an infection. In this study, the efficacy of three immunoenzymatic tests for detecting CagA(+) and CagA(-) infections were compared: immunoblot (Mileni...

BACKGROUND Omeprazole (OMP), a proton pump inhibitor, is a highly effective drug for the management of acid-related disorders. Infections resulting from cytotoxin antigen A (CagA) positive Helicobacter pylori strains have been associated with higher grades of gastric mucosal inflammation. Nuclear factor (NF)-κB activation has been reported to participate in H. pylori-induced gastritis in humans...

The clinical outcome of Helicobacter pylori infection may be associated with the cagA bacterial genotype. To investigate the cagA status of H. pylori-infected patients and the relationship between cagA and peptic ulcer disease, gastric biopsy specimens from 103 Caucasian patients in Brazil were analyzed by PCR. Since allelic variation in cagA exists and distinct H. pylori subgenotypes may circu...