Failure to detect anti-MAG antibodies by RIA in CSF of patients with multiple sclerosis

Using a sensitive double-antibody radioimmunoassay (RIA) we measured IgG antibodies to the myelin-associated glycoprotein (MAG) in cerebrospinal fluid (CSF) of patients with active multiple sclerosis (MS) and with other neurological diseases (OND). Comparable levels of precipitation of radiolabeled MAG were obtained with CSF from the patients of the two groups.