Antigen of 49.6-kDa subunit pili protein of Helicobacter pylori as a potential biomarker for early and rapid detection of the infection

Background and Aim: Helicobacter pylori infection has been identified as a major cause of peptic ulcer diseases, including gastric and duodenal ulcers, gastritis, chronic and gastric carcinoma, and even gastric lymphoma. In vitro studies using Western blotting analysis, hemagglutination test, adherence inhibition assays, and immunocytochemical staining revealed that the 49.6-kDa subunit pili protein of H. pylori was considered an immunogenic protein. This study aimed to develop a serological diagnostic test using 49.6 kDa for detecting antibodies against H. pylori proteins in an early phase of the infection. Materials and Methods: An in-house immunochromatographic test (ICT) kit was developed and used to test a panel of sera sample obtained from a randomly selected symptomatic patient, in which 40 sera were H. pylori positive and 40 sera were H. pylori negative. Results: The results showed that ICT with 49.6 kDa as an antigen was highly sensitive and specific for detecting anti-H. pylori immunoglobulin G antibodies in human serum, with a high negative predictive value. Conclusion: The developed test could be used to exclude H. pylori infection in symptomatic patients.