Neutralization of anti-myelin basic protein by cerebrospinal fluid of multiple sclerosis patients in clinical remission.

Autoantibodies to myelin basic protein (anti-MBP) can be detected in the cerebrospinal fluid (CSF) of MS patients using a solid phase radioimmunoassay. Acute relapses of MS are characterized by an elevated, above unity, free (F) to bound (B) anti-MBP ratio; while in contrast, patients with chronic progressing disease have a low, below unity, free to bound ratio of anti-MBP. As patients with acute relapses enter into remission, the F/B anti-MBP ratio gradually decreases and eventually the level of these autoantibodies becomes undetectable. Neutralization of free anti-MBP was observed in intra- and interpatient experiments in which CSF from MS patients in remission was reacted with CSF of patients with acute relapses. Inhibition of anti-MBP neutralization was produced by CSF from MS patients with chronic progressing disease.