Replication-incompetent adenoviruses as vectors for protective immunization against measles virus infection.

Despite the availability of an efficient live-attenuated measles virus vaccine about 1.5 million annual deaths from measles infections and their complications are recorded worldwide. Particularly in developing countries measles remains an unsolved problem and a new vaccine seems necessary. In our animal model of measles virus infection in rats we studied a candidate vaccine based on infectious replication incompetent (E1A-) adenovirus (RAd) where measles virus genes are expressed under the control of the cytomegalovirus immediate early promoter. The aim of the study was to characterize the cell mediated and humoral immunity after immunization with RAd and its protective effect. After challenge with a lethal dose of measles virus no signs of disease or histopathological changes were detected in RAd68-immunized rats. The elimination of measles virus was successful within a few days. The results demonstrate that defective recombinant adenovirus vectors can induce complete protection from experimental measles infection in rats.