Optic neuritis anti-myelin basic protein synthetic peptide specificity

Abstract

Elevated titers of anti-myelin basic protein (anti-MBP) are highly associated with acute idiopathic unilateral optic neuritis as well as acute relapses of multiple sclerosis (MS). During acute phases of optic neuritis, free/bound antibody ratios are generally above unity, with high titers of free anti-MBP and relatively low or undetectable values of bound antibody. Three to 5 months after the acute phase when the majority of patients have recovered, free/bound anti-MBP ratios are below unity with low titers of free antibody and relatively higher levels of bound anti-MBP. Anti-MBP purified from cerebrospinal fluid of patients with optic neuritis are neutralized by synthetic peptides of human MBP containing overall amino acid residues 61–106 and do not react with synthetic peptides corresponding to residues 1–60 and 107–170. Anti-MBP may either have multiple epitopes in the region corresponding to residues 61–106 or it may react with a discontinuous epitope in this range. The mechanism of the optic nerve demyelination may be associated with anti-MBP binding in situ to MBP ib the 61–106 amino acid region.