Different patterns of glycolipid antibody reactivity: lower motor neuron syndromes vs. immunization

High titers of serum antibodies against G_M1 ganglioside occur frequently in patients with lower motor neuron (LMN) syndromes. We compared the specificities of the antiganglioside antibody reactivities in LMN patients with those arising after immunization of Lewis rats with several ganglioside containing preparations including purified G_M1, human central nervous system (CNS) grey matter and white matter. Serums with high titers of anti-G_M1 antibodies from patients with LMN syndromes usually showed limited cross-reactivity to other glycolipids but often bound to a Gal(β1-)GalNAc-containing neoglycoprotein. In contrast, serums with anti-G_M1 antibody arising after immunization showed broad cross-reactivity with other glycolipids but did not bind to the neoglycoprotein. We conclude that the serum patterns of antiganglioside antibody reactivity secondary to immunization with gangliosides and CNS components are different from the natural autoantibodies found in LMN patients. The antiganglioside antibodies seen in LMN patients are unlikely to be a result of autoreactivity to gangliosides after nervous tissue damage.