The role of heparan sulphate-binding activity of Helicobacter pylori bacteria in their adhesion to murine macrophages.

The aim of this study was to determine the role of heparan sulphate (HS)-binding activity of Helicobacter pylori microbes in their adhesion to and ingestion by inflammatory peritoneal macrophages. Two H. pylori strains expressing sialic acid-specific haemagglutinins but differing in the expression of heparan sulphate-binding capacity were chosen for investigation. The attachment to an ingestion by macrophages of the H. pylori bacteria were estimated by ELISA using anti-H. pylori antibodies. The adhesion of both H. pylori strains could be inhibited by pretreatment of the bacteria with heparin (H), HS or fetuin, as well as by preincubation of the macrophages with heparinase or neuraminidase. However, detailed analysis of the data on the inhibition of bacterial adhesion to macrophages led to the conclusion that the attachment of H. pylori 25 bacteria, which expressed a high heparan sulphate binding, was mainly determined by HS-binding structures. In contrast, the adhesion to macrophages of H. pylori bacteria 17874 microbes, which expressed a weak heparan sulphate binding, was more dependent on the exhibition of sialic acid-dependent haemagglutinins. The described variation in H. pylori bacterial surface structures mediating their adhesion to macrophages could suggest a similar variation in bacterial adhesion to stomach mucosa and maybe in the pathogenicity of H. pylori strains.