ANTIGENIC ANALYSIS OF CURRENT WILD-TYPE AND VACCINE STRAINS OF MEASLES-VIRUS

The antigenic properties of vaccine and wild type strains of measles v irus were compared. Serum specimens from vaccinated persons, persons i nfected during the prevaccine era, or mice experimentally vaccinated w ith the hemagglutinin (H) protein from vaccine virus neutralized vacci ne virus and a wild type measles virus from 1989 equally well. In cont rast, serum specimens from patients with recent measles virus infectio n and mice experimentally vaccinated with the H protein from the wild type virus from 1989 neutralized wild type virus with titers 4-8 times higher than those to vaccine virus. Several H protein-specific monocl onal antibodies could differentially recognize vaccine or wild type vi rus. These data show that the H proteins of the recent wild type virus es contain both conserved and new or modified antigenic determinants a nd are consistent with previous studies that described genetic drift i n the H proteins of recent wild type viruses.