Cell- and antibody-mediated responses to measles and mumps viruses in experimental animals.

Monkeys and guinea pigs were immunized with various doses of measles and mumps viruses. A cell-mediated response measured by leukocyte migration inhibition occured during the first two weeks after immunization. In case of measles virus, marked migration inhibition occurred already on the 7th day in monkeys and guinea pigs immunized with high virus doses. The response declined as early as 14 days after immunization in contrast to the group of guinea pigs inoculated with a lower virus dose. In these animals the response sustained for up to 50 days. Immunization of animals with various doses of mumps virus was similar and positive responses were obtained in the absence of detectable antibodies. Even 2.5 TCID50 of mumps virus induced the response although more irregularly than 250 or 2500 TCID50 virus.