IMMUNOCHEMICAL FEATURES OF A CASE OF PROGRESSIVE RUBELLA PANENCEPHALITIS

Abstract

Progressive rubella panencephalitis (PRP), a slowly progressive and fatal CNS disorder due to rubella virus, is characterized by high CSF levels of Ig, oligoclonal bands and high CSF:serum rubella antibody titer ratios. Sera, CSF and neutral extracts of brain, spleen, lymph node and kidney obtained at autopsy from a case were analyzed for Ig isotype and content by enzyme linked immunosorbent assays. Comparable titers of rubella specific IgA and IgG were found in sera and CSF, but accounted for a disproportionate amount of the isotype specific Ig of CSF (0.19%, 14.0%) as compared to serum (0.02%, 0.69%). The percentage of isotype specific Ig were not increased in extracts of most visceral tissues compared to serum; rubella specific IgA and IgG were disproportionately increased in extracts from most regions of brain sampled (1- to 60-fold and 8- to 27-fold, respectively). No rubella specific IgM could be conclusively demonstrated in any specimen. Immunoprecipitation studies showed that the IgG reacted with the major glycoproteins (gp62, gp47-56 complex) and non-glycosylated polypeptide (p38) of radiolabeled rubella virions and infected cell lysates. A major portion of the rubella specific antibody apparently is produced within the CNS of patients with PRP.