Fine specificities of anti-LM1 IgG antibodies in Guillain-Barre syndrome

We investigated the prevalence of anti-LM1 IgG antibody and its fine specificity in Guillain-Barre syndrome (GBS). Anti-LM1 IgG and IgM antibodies from sera of 47 patients with GBS-19 with acute inflammatory demyelinating polyneuropathy (AIDP), 27 with acute motor axonal neuropathy (AMAN), and I with acute motor-sensory axonal neuropathy (AMSAN)-were tested. Anti-LM1 IgG antibody was detected in only one patient with AMP, whereas it was present in seven with AMAN and in one with AMSAN. Sera from the eight IgG anti-LM1-positive patients with AMAN/AMSAN also had IgG activity against the gangliosides GM 1, GM1b, GD1a, GalNAc-GD1a, GD1b, or GQ1b. Anti-LM1 IgG antibodies from the AMAN/AMSAN patients cross-reacted with other gangliosides, whereas IgG antibody from the AIDP patient was monospecific against LM1. Anti-LM1 IgG antibody therefore, cannot be a marker of AIDP. In addition, whether monospecific anti-LM1 IgG antibody is associated with AIDP remains to be concluded. Larger studies are needed to verify whether monospecific anti-LM1 IgG antibody could be a marker of AIDP. (C) 2002 Elsevier Science B.V. All rights reserved.