Immunoproteomics of Helicobacter pylori infection in patients with atrophic body gastritis, a predisposing condition for gastric cancer.

Atrophic body gastritis is considered an outcome of H. pylori infection at high risk for gastric cancer. Immunoproteomics has been used to detect H. pylori antigens, which may act as potential markers for neoplastic disease and may be used in specific serological tests. We used immunoproteome technology to identify H. pylori antigens, recognized by sera from patients with atrophic body gastritis. Here, we performed 2DE protein maps of H. pylori strain 10K, probed against single sera from 3 groups of H. pylori-positive patients (atrophic body gastritis; intestinal-type gastric cancer; peptic ulcer) and negative controls. Immunoreactive spots were identified by MALDI-TOF-MS. A total of 155 immunoreactive spots were detected corresponding to 14.1% of total spots detected in our reference map of H. pylori strain 10K. Sera from atrophic body gastritis (40.5±2%) and gastric cancer patients (25.9±1.8%) showed a significantly higher and stronger mean immunoreactivity versus H. pylori antigens compared to peptic ulcer patients (11.2±1.3%). The average intensity of immunoreactivity of sera from atrophic body gastritis and gastric cancer patients was significantly stronger compared to peptic ulcer patients. Sera from atrophic body gastritis and gastric cancer patients differentially recognized 17 H. pylori spots. Immunoproteome technology may discriminate between different H. pylori-related disease phenotypes showing a serological immunorecognition pattern common to patients with gastric cancer and atrophic body gastritis, its precursor condition. This tool may be promising for developing specific serological tests to identify patients with gastritis at high risk for gastric cancer, to be evaluated in prospective investigations.