N-ACETYLGALACTOSAMINYL GD1A IS A TARGET MOLECULE FOR SERUM ANTIBODY IN GUILLAIN-BARRE-SYNDROME

Serum antibodies against such major glycolipids as GM1, GD1b, and LM1 have been reported in patients in the acute phase of Guillain-Barre sy ndrome (GBS). Because minor unidentified glycolipids also may be targe ts of antibodies in GBS sera, we assayed serum antibody against a crud e ganglioside fraction using thin-layer chromatogram immunostaining. A ntibody activity was detected against a band that migrated just below GD1a in 6 of the 50 patients with GBS tested. Antibody titer, as deter mined by enzyme-linked immunosorbent assay, decreased during the cours e of the disease. All 6 patients had suffered gastrointestinal infecti on before the neurological onset of GBS and showed low amplitudes for the compound muscle action potentials and normal or only slightly decr eased nerve conduction velocities. Thin-layer chromatogram immunostain ing did not show this antibody activity in any of the 16 normal and 11 9 disease controls; The unidentified glycolipid was isolated by DEAE-S ephadex A-25 column chromatography, sialidase treatment, and Iatrobead s column chromatography. Fast atom bombardment-mass spectra showed it to be N-acetylgalactosaminyl GD1a.