Monoclonal IgM antibodies to GM1 and asialo-GM1 in chronic neuropathies cross-react with Campylobacter jejuni lipopolysaccharides.

We tested monoclonal IgM anti-GM1 and asialo-GM1 antibodies from 6 patients with chronic motor neuropathies for binding to lipopolysaccharides (LPS) from three stains of Campylobacter jejuni. Four of the 6 patients showed strong reactivity with LPS from at least one of the three C. jejuni strains tested as shown by enzyme-linked immunosorbent assay or western blot. Preabsorption with GM1 or asialo-GM1, or blocking with cholera toxin, prevented antibody binding to LPS. These studies indicate that human anti-GM1 or anti-asialo-GM1 antibodies cross-react with LPS from certain strains of C. jejuni, and that bacterial LPS might provide antigenic stimuli for the activation of B cells expressing anti-GM1 antibodies.