Anti-ganglioside complex IgM antibodies in multifocal motor neuropathy and chronic immune-mediated neuropathies

Sensitivity and predictive value of anti-GM1/galactocerebroside IgM antibodies in multifocal motor neuropathy

“…As was previously postulated for anti-ganglioside complex antibodies,22 23 it is possible that the mixture of GM1 with galactocerebroside leads to the formation of a new antigen recognised by patients’ IgM. All our patients with MMN with anti-GM1 IgM also had anti-GM1/GalC IgM that in most patients were found in higher concentration (figure 2).…”

An Update on Monoclonal Gammopathy and Neuropathy

“…For example, in a case series of patients with chronic neuropathies, a patient with motor neuropathy had biclonal IgM kappa and IgM monoclonal antibodies bound to the GM2-GD1b complex, but not to individual gangliosides [44]. The pathologic significance of this finding remains to be seen.…”

Improving the detection of IgM antibodies against glycolipids complexes of GM1 and Galactocerebroside in Multifocal Motor Neuropathy using glycoarray and ELISA assays

“…The ELISA tests were performed in previous studies with a 1:10 ratio of GM1 and GalC with (Pestronk et al, 1997) or without (Nobile-Orazio et al, 2010) the adjunction of cholesterol sulfate. In these studies, the gains in sensitivity were similar, ranging from 19% to 27%, but with a loss of specificity which dropped below 90% (Nobile-Orazio et al, 2010).…”

“…As previous studies used weight to weight ratios of glycolipids extending from 1:1 (Galban-Horcajo et al, 2013) to 1:10 (Pestronk et al, 1997;Nobile-Orazio et al, 2010), we formed the complexes of GM1 and GalC in three different proportions by mixing GM1 and GalC at a weight-to-weight ratio equivalent to 1:1 (GM1:GalC), 1:5 (GM1: GalC5) and 1:10 (GM1:GalC10). Since the molecular weight of GalC (858 g/Mol) is approximately half that of GM1 (1547 g/Mol), this …”

“…As they can also be found in up to 10% of ALS cases (Kuijf et al, 2005) and in normal and other disease controls, IgM isotype anti-GM1 antibodies are not specific for MMN. Testing antibodies against heteromeric complexes of GM1 and galactocerebroside (GalC) increases the sensitivity of antibody detection in MMN using either ELISA (Pestronk et al, 1997;Nobile-Orazio et al, 2010) or a modified dot-blot, herein termed glycoarray (Galban-Horcajo et al, 2013). Previous studies used different ratios of glycolipids to make the GM1:GalC complexes, extending from 1:1 (Galban-Horcajo et al, 2013) to 1:10 weight to weight ratio (Pestronk et al, 1997;Nobile-Orazio et al, 2010).…”