DNA-mediated immunizations have been used to raise neutralizing antibodies for measles virus. Single inoculations of plasmids expressing measles hemagglutinin or fusion glycoproteins raised neutralizing antibody in BALB/c mice. Plasmids expressing the hemagglutinin glycoprotein (both normal and secreted) raised neutralizing responses that persisted for 1 year. For both forms of hemagglutinin, the effectiveness of the raised antibody (ratio of neutralizing activity to ELISA activity) was similar. High titers of neutralizing antibody were also raised by inoculation of rabbits with the hemagglutinin and fusion glycoprotein-expressing plasmids.