Human monoclonal immunoglobulin M antibodies to ganglioside GM(1) show diverse cross-reactivities with lipopolysaccharides of Campylobacter jejuni strains associated with Guillain-Barre syndrome

We examined the reactivity of a panel of anti-GM(1) immunoglobulin M monoclonal antibodies (MAbs) cloned from multifocal motor neuropathy patients with lipopolysaccharides (LPSs) of Campylobacter jejuni strains, including serotype O:41 strains associated with Guillain-Barre syndrome. The MAbs reacted with ganglioside GM(1) to different degrees, and these differences in fine specificities for GM(!) were reflected in the different degrees of reactivity with each of the C. jejuni LPSs tested. Antibodies could also be discriminated by the varying patterns of inhibition by cholera toxin (a GM(1) ligand) in LPS binding studies. These results indicate that there is a substantial heterogeneity among C. jejuni O:41 strains in their expression of GM(1)-like epitopes and among the fine specificities of different neuropathy-associated anti-GM(1) antibodies.