Helicobacter pylori cytotoxin: a novel ligand for receptor-like protein tyrosine phosphatase beta (review).

The impacts of toxins are generally observed as acute intoxications, whereas the environmental health effects of chronic exposure to mostly low levels of toxins are only poorly documented and are an emerging issue. Furthermore, toxins are potentially useful as tools to study the physiological role of particular channels or to determine structural features of channels that are important for their function. Recent studies suggest that vacuolating cytotoxin (VacA) is a novel ligand for receptor protein tyrosine phosphatase (RPTP) beta. VacA is a virulence factor of Helicobacter pylori that is involved in gastric ulceration and cancer in experimental animals and humans. VacA may represent the chronic exposure of A-B family of bacterial endotoxins and be a useful probe for RPTPbeta functions in the gastrointestinal system.