TYPING OF HELICOBACTER-PYLORI WITH MONOCLONAL-ANTIBODIES AGAINST LEWIS ANTIGENS IN LIPOPOLYSACCHARIDE

Recently, it has been shown that the lipopolysaccharide (LPS) O antige n of Helicobacter pylori contains Lewis x (Le(x)), Lewis y (Le(y)), or both Le(x) and Le(y) antigens. We applied a serotyping method for H. pylori by an enzyme-linked immunosorbent assay with monoclonal antibod ies (MAbs) specific for these antigens and the related fucosylated H t ype 1 (H1) antigen. The selected MAbs recognized the Le(x) and/or Le(y ) structures in the LPS of H. pylori. The agreement between the result s of biochemical compositional analysis and the serological data valid ated our serotyping system. A total of 152 strains from different geog raphic origins (The Netherlands, Canada, Poland, Italy, and People's R epublic of China) were examined for typeability based on the presence of Lewis antigens. One hundred twenty-nine (84.9%) strains were typeab le, and 12 different serotyping patterns were observed; 80.9% of the s trains contained Le(x) and/or Le(y) antigens, and 18.4% reacted with t he MAb against the related H1 antigen either alone or in combination w ith the Le(x) and/or Le(y) antigen. Our results show that the Le(x) an d Le(y) antigens are frequently encountered in the LPS of H. pylori st rains from various geographic origins. This typing method is an easy-t o-perform technique, which can be used for strain differentiation in e pidemiological studies of H. pylori infections.