title: Ganglioside GD1b is the target antigen for a biclonal IgM in a case of sensory-motor axonal polyneuropathy: involvement of N-acetylneuraminic acid in the epitope.
abstract: We report on a 54-year-old man with a sensory-motor polyneuropathy associated with a biclonal IgM-kappa gammopathy, which reacted with the ganglioside GD1b. Examination of nerve biopsy specimens showed some reduction in the density of myelinated fibers and axonal degeneration with a loss of large fibers and a relative increase in the density of small fibers. Immunodetection on thin-layer chromatography of the glycolipid antigens showed strong reactivity of the patient's serum IgM-kappa with GD1b ganglioside and weak binding to GD1a. biclonal IgM antibodies did not react with GM1, asialo-GM1, GT1b, GD2, or GD3. Indirect immunofluorescence staining showed binding of IgM-kappa mainly in a crescent-like pattern on the internal side of myelin sheaths, which could correspond either to an enlarged periaxonal (adaxonal) space or to the internal mesaxon or to both. The immunostaining was abolished after absorption of the serum with GD1b.
authors.affiliation: INSERM Unit 134 Neurobiologie cellulaire moléculaire et clinique, Hôpital de la Salpêtrière, Paris, France.
authors.forename: A B
authors.initials: AB
authors.lastname: Younes-Chennoufi
authors.forename: J M
authors.initials: JM
authors.lastname: Léger
authors.forename: J J
authors.initials: JJ
authors.lastname: Hauw
authors.forename: J L
authors.initials: JL
authors.lastname: Preud'homme
authors.forename: P
authors.initials: P
authors.lastname: Bouche
authors.forename: P
authors.initials: P
authors.lastname: Aucouturier
authors.forename: H
authors.initials: H
authors.lastname: Ratinahirana
authors.forename: C
authors.initials: C
authors.lastname: Lubetzki
authors.forename: O
authors.initials: O
authors.lastname: Lyon-Caen
authors.forename: N
authors.initials: N
authors.lastname: Baumann
mesh_terms: D000941:Antigens / Q000276:immunology; D015153:Blotting, Western; D000939:Epitopes; D005732:Gangliosides / Q000276:immunology*; D006801:Humans; D007075:Immunoglobulin M / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D019158:N-Acetylneuraminic Acid; D009422:Nervous System Diseases / Q000276:immunology*; D010543:Peroneal Nerve / Q000276:immunology; D012677:Sensation / Q000502:physiology*; D012794:Sialic Acids / Q000276:immunology*; D013194:Staining and Labeling
chemical_list: D000941:Antigens; D000939:Epitopes; D005732:Gangliosides; D007075:Immunoglobulin M; D012794:Sialic Acids; C033851:ganglioside, GD1b; D019158:N-Acetylneuraminic Acid