Typing of Helicobacter pylori with monoclonal antibodies against Lewis antigens in lipopolysaccharide

Abstract

Recently, it has been shown that the lipopolysaccharide (LPS) O antigen 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 antibodies (MAbs) specific for these antigens and the related fucosylated H type 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 results of biochemical compositional analysis and the serological data validated our serotyping system. A total of 152 strains from different geographic origins (The Netherlands, Canada, Poland, Italy, and People's Republic of China) were examined for typeability based on the presence of Lewis antigens. One hundred twenty-nine (84.9%) strains were typeable, and 12 different serotyping patterns were observed; 80.9% of the strains contained Le(x) and/or Le(y) antigens, and 18.4% reacted with the MAb against the related H1 antigen either alone or in combination with the Le(x) and/or Le(y) antigen. Our results show that the Le(x) and Le(y) antigens are frequently encountered in the LPS of H. pylori strains from various geographic origins. This typing method is an easy-to-perform technique, which can be used for strain differentiation in epidemiological studies of H. pylori infections.