Fig. 3

Distribution of anti-self glycan glycolipid and anti-GA1 antibodies in the different subpopulations of neurological disorder patients. Within each pie chart, the number of patients presenting antibody reactivity of the IgM (“IgM only”, blue), IgG (“IgG only”, red) or both isotypes (“IgM & IgG”, green) against the different self glycan glycolipids is displayed for each patient subpopulation and for all patients combined. The fraction of pie chart depicting “IgG only” reactivity represents the percentage of IgG/IgM discordance. Similar information is presented for anti-GA1 antibodies (non-self glycan glycolipid). “Self glycan A” subgroup comprises antibodies against GM1, GD1b and GM2, for which IgM reactivity populations have been characterized in normal human sera. “Self glycan B” subgroup includes antibody reactivity detecting the remaining glycolipids (GM3, GD3, GD1a, GT1b and GQ1b). “Sub-total A” plots sum the data for all “self glycan A” subgroup antibodies, while “sub-total B” column does it for all “self glycan B” subgroup antibodies. Far right column (“Total”) combines the data for all the anti-self glycan glycolipid antibodies. Total IgG/IgM discordance comparisons between each subpopulation of neurological disorder patients were statistically not significant. Comparisons of “sub-total A” versus “sub-total B” IgG/IgM discordance within each subpopulation of neurological disorder were not significant, whereas for “All patients” data combined, the comparison was statistically meaningful (Fisher’s exact test; ****, p < 0.0001). ALS, amyotrophic lateral sclerosis; GBS, Guillain-Barré syndrome; AMN, asymmetric motor neuropathy; CIDP, chronic inflammatory demyelinating polyneuropathy; SN, sensory neuropathy; MMN, multifocal motor neuropathy; SMN, sensory motor neuropathy; MFS, Miller Fisher syndrome; LMND, lower motor neuron disease; MN, mononeuropathy; Other, other neuropathies (see Methods and Additional file 1 for full details)