Successful DNA immunization against measles: Neutralizing antibody againsteither the hemagglutinin or fusion glycoprotein protects rhesus macaques without evidence of atypical measles

Measles remains a principal cause of worldwide mortality, in part because y oung infants cannot be immunized effectively. Development of new vaccines h as been hindered by previous experience with a formalin-inactivated vaccine that predisposed to a severe form of disease (atypical measles). Here we h ave developed and tested potential DNA vaccines for immunogenicity, efficac y and safety in a rhesus macaque model of measles. DNA protected from chall enge with wildtype measles virus. Protection correlated with levels of neut ralizing antibody and not with cytotoxic T lymphocyte activity. There was n o evidence in any group, including those receiving hemagglutinin-encoding D NA alone, of 'priming' for atypical measles.