Detection of anti-GM1 ganglioside antibodies in patients with neuropathy by a novel latex agglutination assay.

Highly elevated titers of serum anti-GM1 ganglioside antibodies are closely associated with multifocal motor neuropathy, but low titers are commonly present in normal individuals or other diseases. Current systems for measuring anti-GM1 antibodies utilize the enzyme-linked immunosorbent assay (ELISA), in which serum dilutions are tested for binding to excess antigen immobilized on the surface of microwells. The ELISA system, however, is relatively time consuming, labor intensive, and costly, in addition to being prone to methodological variability. We have developed a novel agglutination assay for the detection of anti-GM1 antibodies, utilizing GM1 ganglioside-coated latex beads. In contrast to the ELISA system, antibody titers may be quantified by testing for agglutination using latex beads coated with decreasing amounts of antigen. The agglutination assay compares favorably to the ELISA system in sensitivity and specificity, but is considerably less costly and takes only a few minutes to perform.