Association of Helicobacter pylori gastric infection with the suppressed Thomsen-Friedenreich antigen natural humoral response.

BACKGROUND: A low natural humoral immune response to Thomsen-Friedenreich antigen (TFA) is a general phenomenon in patients with cancer, including gastric cancer, and in some premalignant conditions. It has been also shown that Helicobacter pylori infection is associated with increased risk of gastric cancer. The possible link between the TFA immune response and H. pylori infection was investigated. METHODS: Enzyme-linked immunosorbent assay with H. pylori cell surface glycine extract as antigen and microhemagglutination of neuraminidase-treated blood group O donor erythrocytes were used for evaluation of IgG H. pylori antibody and TFA agglutinin levels in sera from patients with gastric cancer (n = 39) or ulcer of the stomach (n = 36) and controls (n = 49). RESULTS: The tendency to an inverse relationship between the two events was found in all groups studied, including cancer. H. pylori-seronegative persons had higher TFA natural antibody titer than the related H. pylori-seropositive groups. When log2 of TFA antibody titer > 4 for strong TFA responders and H. pylori relative antibody activity > 25 for H. pylori-seropositive persons were chosen as cut-off limits, the association was statistically significant (p < 0.02). TFA antibody level was decreased in cancer patients as compared with controls (p < 0.002). No relation to age, stage of the disease, or tumor morphology was noted. CONCLUSION: The data suggest that the TFA natural immune response, which is known to participate in tumor-host relationships, is also involved in H. pylori-host interactions, probably as a natural factor of resistance against H. pylori infection.