Anti-GD1a antibody is associated with axonal but not demyelinating forms of Guillain-Barre syndrome.

Immunopathological studies suggest that the target of immune attack is diff erent in the subtypes of Guillain-Barre syndrome (GBS). In acute motor axon al neuropathy (AMAN), the attack appears directed against the axolemma and nodes of Ranvier. In acute inflammatory demyelinating polyneuropathy (AIDP) , the attack appears directed against a component of the Schwann cell. Howe ver, the nature of the antigenic targets is still not clear. We prospective ly studied 138 Chinese GBS patients and found that IgG anti-GD1a antibodies were closely associated with AMAN but not AIDP. With a cutoff titer of gre ater than 1:100, 60% of AMAN versus 4% of AIDP patients had IgG anti-GD1a a ntibodies; with a cutoff titer of greater than 1:1,000, 24% of AMAN patient s and none of the AIDP patients had IgG anti-GD1a antibodies. In contrast, low levels of IgG anti-GM1 antibodies (>1:100) were detected in both the AM AN and the AIDP forms (57% vs 35%, NS). High titers of IgG anti-GM1 (>1:1,0 00) were more common in the AMAN form (24% vs 8%, NS). Serological evidence of recent Campylobacter infection was detected in 81% of AMAN and 50% of A IDP patients, and anti-ganglioside antibodies were common in both Campyloba cter-infected and noninfected patients, Our results suggest that IgG antibo dies antibodies may be involved in the pathogenesis of AMAN.