Fig. 2

IgG/IgM discordance of IgG antibodies against diverse non-self and self glycan-carrying glycolipids analyzed in this study. Percentage of IgG/IgM discordance (percentage of samples having IgG antibodies with IgM antibodies of the same specificity) in patients with neurological disorders (positive for anti-self glycans and for anti-non-self glycans IgG antibodies of defined specificity). Oligosaccharide sequence of each glycosphingolipid recognized by antibodies is displayed. IgG/IgM discordance comparisons between “non-self glycan-”, “self glycan A” and “self glycan B” reactivities (these latter divided by a dashed line, see Methods) were all statistically significant (p < 0.0001, Fisher’s exact test). Anti-GA1 antibodies were measured in all patient samples, whereas the remaining anti-non self glycan antibodies were evaluated in a randomly selected fraction of patient sera (n = 30) that were positive for anti-self glycan IgG antibodies