The mechanical binding strengths of Helicobacter pylori BabA and SabA adhesins using an adhesion binding assay–ELISA,and its clinical relevance in Japan

To elucidate a potential role for H. pylori BabA and SabA adhesins in the pathogenesis of gastric mucosal lesions, the MBS of BabA and SabA was examined using an in‐house ABA‐ELISA. Ninety isolates from Japanese patients with gastric cancer (n= 43) and non‐cancerous (n= 47) lesions were subjected to an ABA‐ELISA which had been developed in‐house, and sequential analysis of the babA2 middle region. The BabA‐MBS was significantly higher in the cancer than the non‐cancer group (P= 0.019), but there was no significant difference for SabA‐MBS. A weak correlation between BabA‐MBS and SabA‐MBS (r= 0.418) was observed, the positive correlation being higher in the cancer than the non‐cancer group (r= 0.598 and 0.288, respectively). The isolates were classified into two groups: a BabA‐high‐binding and a BabA‐low‐binding group (in comparison to the average for BabA‐MBS). The average SabA‐MBS in the BabA‐high‐binding group was significantly higher than in the BabA‐low‐binding group (P < 0.0001). Analysis of babA2 middle region diversity (AD1–5) revealed that AD2‐type was predominant in isolates irrespective of BabA‐MBS. H. pylori BabA‐MBS might have an effect on SabA‐MBS and relate to the severity of gastric disorders, including gastric cancer. Evaluation of MBS of the combined two adhesins would be helpful for predicting damage in the H. pylori infected stomach.