Differences in surface-exposed antigen expression between Helicobacter pylori strains isolated from duodenal ulcer patients and from asymptomatic subjects

We have analyzed possible qualitative and quantitative differences in antig en expression between Helicobacter pylori strains isolated from the antrum and different locations in the duodenum of 21 duodenal ulcer (DU) patients and 20 asymptomatic subjects (AS) by enzyme-linked immunosorbent assay (ELI SA) and inhibition ELISA. Almost all antral and duodenal strains grown in v itro expressed the N-acetyl-neuroaminyllactose-binding hemagglutinin, flage llins (subunits FlaA and FlaB), urease, a 26-kDa protein, and a neutrophil- activating protein. In 75% of both the DU patients and the AS, antral H. py lori strains expressed either the blood group antigen Lewis y (Le(y)) alone or together with the Le(x) antigen. However, duodenal H. pylori strains of DU patients expressed Le(y) antigen more frequently than corresponding str ains of AS (P < 0.05). Presence of Le(y) on H. pylori was related to the de gree of active duodenitis (P < 0.05), Duodenal H. pylori strains isolated f rom AS were significantly more often Lewis nontypeable than duodenal strain s of DU patients (P < 0.01), Presence of H. pylori blood group antigen-bind ing adhesin (BabA) was significantly higher on both antral and duodenal str ains isolated from DU patients than on corresponding strains isolated from AS (P < 0.05). BabA-positive duodenal H, pylori strains isolated from DU pa tients were associated with active duodenitis more frequently than correspo nding strains isolated from AS (P < 0.01). Infection with H. pylori strains positive for Le(y) and BabA in the duodenum is associated with development of duodenal ulcer formation.