Chemoenzymatic Synthesis of Lipo-oligosaccharide Core Domains to Examine Guillain-Barré Syndrome Serum Antibody Specificities.

Guillain-Barré syndrome is often caused by infection that has induced antibodies to the lipo-oligosaccharide (LOS) that cross-react with gangliosides at peripheral nerves causing polyneuropathy. To examine fine specificities of anti-ganglioside antibodies and develop a more robust platform for diagnosis and disease monitoring, we developed a chemoenzymatic approach that provided an unprecedented panel of oligosaccharides composed of the inner-core of the LOS of extended by various ganglioside mimics. The compounds and corresponding ganglio-oligosaccharides were printed as a microarray to examine binding specificities of lectins, anti-ganglioside antibodies, and serum antibodies of GBS patients. Although lectins and anti-ganglioside antibodies did not differentiate the ganglio-oligosaccharides and mimics, the patient serum samples bound much more strongly to the ganglioside mimics. The data indicate that antibodies have been elicited to a foreign epitope that includes a heptosyl residue unique of bacterial LOS and that these antibodies subsequently cross-react with lower affinity to gangliosides. The microarray detected anti-GM1a antibodies with high sensitivity and will be attractive for diagnosis, disease monitoring, and immunological research.