CSF protein examinations with thin-layer isoelectric focusing in multiple sclerosis.

Thin-layer IEF, due to its extremely high resolving capacity, has been found to be quite valuable for CSF protein examinations, one important advantage of the technique being its excellent capacity for separation of immunoglobulins. The CSF and serum proteins of 230 patients with clinically verified or probable MS and 20 subjects with optic neuritis were examined with thin-layer IEF and the findings were compared with clinical data and results of other CSF examinations. All but 3 of the MS patients and about two thirds of the subjects with optic neuritis inhibited one or combinations of different CSF protein aberrations in the acidic and alkaline range. Oligoclonal bands and/or regional increases of Ig fractions, changes compatible with intrathecal Ig synthesis, were detected in respectively 95 and 80% of patients with clinically verified and probable MS and 30% of subjects with optic neuritis. Other aberrant CSF protein fractions (including transferrin, the taufraction and gamma-trace protein) were found in about half of the cases; some of these fractions had the highest occurrence in patients with the most extensive Ig abnormalities. The diverse CSF protein aberrations seemed to be influenced by the duration and course of the disorder as well as the probable sites of lesions; further factors might be the release of decomposition products from destroyed tissues, the genetically determined reactivity of the individual and the presence of possible agents.