Presence and isotype of anti-ganglioside antibodies in healthy persons, motor neuron disease, peripheral neuropathy, and other diseases of the nervous system.

Antibodies of the IgM, IgG and IgA class against GM1, asialo-GM1, GD1b and GM2 gangliosides were determined in the sera of patients with motor neuron disease (MND), peripheral neuropathy, other neurological diseases (OND) and healthy individuals. Antibodies of the three immunoglobulin classes were present in healthy persons. MND patients did not differ from OND or controls in anti-GM1 titers of the three isotypes. In the group of peripheral neuropathy, no elevations of antibody titers were observed in patients with sensory or sensory-motor neuropathy; however, four out of 12 patients with the motor variety had very high levels of IgM or IgG antibodies. Two of these four patients also had increased titers of IgA antibodies, but no patients exhibited high titers restricted to this isotype.