Helicobacter pylori-associated gastritis is related to babA2 expression without heterogeneity of the 3' region of the cagA genotype in gastric biopsy specimens.Pathobiology. 2007; 74(5):309-16.P
Cytotoxin-associated gene A (cagA) is the major virulence factor of Helicobacter pylori strains and affects the clinical outcome of patients. Blood group antigen binding adhesin (BabA) helps the strains adhere to the epithelial cell layer and is the most important adhesin of H. pylori.
We tried to study the association between the status of babA2 and cagA in H. pylori strains and histological gastritis. methods: Thirty-six patients were included. RNA was extracted from two frozen biopsy samples of the antrum and corpus, respectively, and cagA/babA2 genotypes were analyzed with reverse transcription polymerase chain reaction and direct sequencing. Two gastric specimens of the antrum and corpus, respectively, were also stained with hematoxylin and eosin to analyze H. pylori-related gastritis.
In the antrum, 56% of the specimens were babA2 positive and in the corpus 53%. The gastritis scores of activity and inflammation were associated with the presence of babA2 in antrum specimens but not in corpus specimens. cagA gene encoding in the CagA EPIYA-D region was detected in all samples, and the sequence was completely identical between those from the gastric corpus and antrum.
babA2 expression is heterogeneous and correlated with the extent of gastritis in the antrum, but not in the corpus, whereas cagA shows a monotonous genotype.