Objective: To explore the characteristics of Helicobacter pylori (H. pylori) antigen in serum and to evaluate its clinical diagnostic value.
Methods: Enzyme-linked immunosorbant assay (ELISA) was developed to detect the soluble H. pylori antigen (S-Hp) and circulatory specific H. pylori antigen immunocomplexes (Hp-IC) in serum.
Results: The positive rate of S-Hp was 90.91% from 66 patients with H. pylori infection, which was much greater than 0% found in 28 controls (P < 0.001). Moreover, its concentration closely reflected the number of H. pylori in the gastric mucosa layer. We also found that Hp-IC existed bound with IgG and/or IgA in patients with positive S-Hp. However, there is no evidence to show the concentration of S-Hp reduced significantly in followed-up subjects after effective therapy.
Conclusions: These methods as newly and noninvasive complementary tools can be used for clinical diagnosis of H. pylori infection. In addition, S-Hp and Hp-IC may be of importance in H. pylori pathogenesis.