Immunodetection of anti-MAG IgM antibody by cross-reactivity to LA-N-1 neuroblastoma cells

Demyelinating polyneuropathiy associated with IgM paraproteinemia and high titers of anti-MAG IgM antibodies (MAG-PN) is considered different from chronic inflammatory demyelinating polyneuropathy, particularly because of the poorer response to treatment of MAG-PN patients. Therefore, anti-MAG anitbodies may have relevant prognostic value. Available anti-MAG antibody assays require central nervous system myelin proteins from autopsied human brains. This study investigated the feasibility of detecting anti-MAG antibody by immunofluorescence and flow cytometry using a panel of human neuroblastoma cell lines as targets. We report here on the evaluation of the LA-N-1 cell line as an appropriate substrate for the detection of anti-MAG antibody by indirect immunoflourescence.