[Bacteriological status, serotypes, and biotypes of Helicobacter pylori]

To divide H. pylori strains into subgroup for an etiological survey, some attempts have been made to determine serotypes or biotypes. A variety of serogroups was observed with a slide agglutination test between S. aureus sensitized with antisera and cells of H. pylori (Danielson et al, 1988). Three or more serotypes were obtained by using antisera absorbed with heterogeneous strains (Tanaka et al, 1990). Furthermore, the possible existence of serological subgroups or subtypes by ELISA was observed (Inouye et al, 1991). H. pylori strains were biotyped with preformed enzyme profiles (APIZYM). The strains were predominantly biotype II, and 4 subsets of the organisms were defined on a combination of motility and cytotoxin production, followed by further detailed types (Owen et al, 1991).