Comparison of three serological methods for detection of Lewis antigens on the surface of Helicobacter pylori.

Chemical studies have shown that lipopolysaccharide (LPS) from certain strains of Helicobacter pylori expresses the Lewis (Le) blood group antigens, predominantly Le(x) and/or Le(y). Serological methods have been used in a number of studies to assess the level of Le expression by H. pylori. However, serological and chemical analyses of a strain's LPS do not always agree. The purpose of this study was to evaluate and compare serological methods used to detect the expression of these antigens by H. pylori. A set of 34 Irish clinical isolates and three culture collection strains had their Le antigen expression assessed using three serological methods, serodot, Western blotting and enzyme-linked immunosorbent assay. A combination of all three methods was used to estimate Le(x) (59%) and Le(y) (94%) expression and this may allow a more accurate assessment of Le expression by isolates for pathogenesis studies.