Serum antibodies to conformational and linear epitopes of myelin oligodendrocyte glycoprotein are not elevated in the preclinical phase of multiple sclerosis

Background: The proposed predictive value of serum anti-myelin antibodies for the development of multiple sclerosis after a first clinically isolated syndrome was recently challenged. Objective: To investigate myelin autoantibodies before first disease manifestation using different detection methods. Methods: Patients with multiple sclerosis who had donated blood at a time prior to development of clinically isolated syndrome were identified via the German National Multiple Sclerosis Society. Control sera were obtained from age- and gender-matched blood donors. IgG-/IgM-antibodies against the extracellular part of native, cell surface-expressed myelin oligodendrocyte glycoprotein were detected by flow cytometry. Antibodies against linear epitopes were identified by immunoblot using recombinant myelin oligodendrocyte glycoprotein (aa1-125) and human myelin basic protein preparations. Results: Fifty eight serum samples from 25 patients covering an interval of 7.3 years-2 months prior to disease onset were available. Longitudinal investigations were performed in 19 patients (2-14 samples per patient, 7 years-2 months prior to disease onset). No significant differences in the prevalence or titres of anti-myelin antibodies were detected between sera of preclinical individuals and healthy donors by either flow cytometry or immunoblot. There was no correlation between interval before clinically isolated syndrome and autoantibody status. Occurrence of antibodies was not associated with symptomatology/severity of clinically isolated syndrome. Conclusion: Neither anti-myelin autoantibodies against cell surface-expressed native myelin oligodendrocyte glycoprotein nor against linear epitopes have a predictive or discriminative role during the preclinical disease phase for developing clinically isolated syndrome or multiple sclerosis later in life.