Replication and immunogenicity of Ad7-, Ad4-, and Ad5-hepatitis B virus surface antigen recombinants, with or without a portion of E3 region, in chimpanzees

Human adenovirus vectors containing intact or largely deleted E(3) region were used to construct adenovirus-hepatitis B recombinant viruses (Ad-HepB) and shown to produce substantial amount of recombinant protein, hepatitis B surface antigen (HBsAg), in tissue culture. Previously we showed that these viruses were able to elicit good anti-HBs antibodies in a dog model. In the present study, the Ad-HepB viruses were evaluated for replication and immunogenicity in chimpanzees which sustain permissive infection by human adenoviruses. Recombinants containing entire E(3) region showed better replication pattern than their E(3) deleted counterparts as evidenced by longer duration and high titers of virus shedding. The effect of E(3) region was also seen in the antibody titers against HBsAg in that the E(3) containing viruses showed better response than the E(3) deleted viruses. The importance off, region for the development of adenovirus vectored vaccines is further discussed. (C) 1997 Published by Elsevier Science Ltd.