Oligoclonal IgG in multiple sclerosis and subacute sclerosing panencephalitis brains

IgG was obtained from multiple sclerosis (MS) and subacute sclerosing panencephalitis (SSPE) brain materials by elution at neutral and acid pH, and by freezing and thawing. Serum, cerebrospinal fluid (CSF), and brain eluates were compared by isoelectric focussing (IEF) with sensitive peroxidase-anti-IgG staining. In 3 MS cases, different plaques or regions of the same brain had IgG patterns with some common and some different bands. Pooled white matter eluates contained the summation of bands seen in individual plaques or regions. Comparison of serum, CSF, and neutral and acid brain eluate IgG patterns showed many common bands but also unique bands. In two SSPE cases, eluates from different regions of the same brain showed virtually identical IgG patterns. Comparisons of serum, CSF, and neutral and acid eluates of the same brain also showed a common pattern of bands. Similarities in IgG patterns of sera, CSF, and regional brain eluates, from single cases of SSPE, suggest a common response to the same antigen in all regions or compartments. Differences in IgG patterns of sera, CSF, pooled brain eluates, and plaques or regional eluates from single cases of MS, suggest: either that (a) all MS oligoclonal IgG is "nonsense' antibody in terms of disease pathogenesis, or (b) much of the MS oligoclonal IgG is "nonsense' antibody, present as part of a specific oligoclonal immune reaction.