[Antibodies to GM1 ganglioside in motor neuron disease--in comparison with demyelinating neuropathy].

We studied serum antibodies to GM1 ganglioside by enzyme linked immunosorbent assay (ELISA) in 55 patients with motor neuron disease (MND) composed of 36 ALS and 19 lower motor neuron disease (LMND), 44 patients with demyelinating neuropathy (DN) composed of 29 Guillain-Barré syndrome (GBS) and 15 chronic inflammatory demyelinating polyneuropathy (CIDP), and 21 healthy controls. High levels of serum antibodies against GM1 were confirmed by thin-layer chromatography overlay procedure. In MND group, the mean level of anti-GM1 IgM antibodies was not significantly elevated in comparison with controls. There was no significant difference in anti-GM1 antibodies between ALS group and LMND group, while anti-GM1 IgM antibodies in DN group, especially in GBS group, were significantly elevated (p < 0.001). High levels of anti-GM1 IgM antibodies (greater than the mean level plus 3 standard deviations of controls) were detected in 9 patients (6 with ALS and 3 with LMND) with MND (16.4%) and 16 patients (11 with GBS and 5 with CIDP) with DN (36.4%). Serum antibodies to GM1 reacted with GD1b ganglioside in only one patient with MND and 10 patients (8 with GBS and 2 with CIDP) with DN. Anti-GM1 IgG antibodies were elevated significantly in DN group. There was no correlation among anti-GM1 IgM antibodies and both duration and severity of illness in MND. In some patients with MND, levels of anti-GM1 IgM antibodies became high in the advanced stage. It is unclear whether these antibodies are primary manifestation or consequence of motor neuron disease.(ABSTRACT TRUNCATED AT 250 WORDS)