Comparison of immune response to rubella virus proteins in early and late natural infections.

The immunological response to rubella virus structural proteins was analyzed by immunoprecipitation assay in sera collected in Cordoba, Argentina, during early convalescence and after remote natural infections. All of the viral structural proteins, the two glycoproteins E1 and E2, and the nucleocapsid C protein, were precipitated by sera obtained from patients soon after infection. By contrast, C reactive antibodies were not detected in sera from remote infections. These results suggest that E1 and E2 play a major role in the long-lasting protective immunity to rubella virus.