Development of an Immunoassay for Rapid Detection of Ganglioside GM 1 Mimicry in Campylobacter jejuni Strains

Abstract
Mimicry of peripheral nerve gangliosides by Campylobacter jejuni lipopolysaccharides (LPSs) has been proposed to induce cross-reacting antiganglioside antibodies in Guillain-Barré syndrome (GBS). Because current methods for LPS characterization are labor-intensive and inhibit the screening of large numbers of strains, a rapid GM 1 epitope screening assay was developed. Biomass from two agar plates of confluent growth yielded sufficient LPS using a novel phenol-water and ether extraction procedure. Extracts of LPS were reacted with cholera toxin (GM 1 ligand), peanut agglutinin (Galβ1→3GalNAc ligand), and anti-GM 1 antibodies. After the assay was validated, 12 of 59 (20%) C. jejuni serostrains, including four serotypes that have not previously been associated with GBS, reacted with two or more anti-GM 1 ganglioside reagents. Subsequently, LPS extracts from 5 of 7 (71%) C. jejuni isolates and 2 of 3 (67%) C. jejuni culture collection strains bore GM 1 structures. Overall, the assay system was reliable, efficient, and reproducible and may be adapted for large-scale epidemiological studies.