Oral Vaccination of Mice with Adenoviral Vectors Is Not Impaired by Preexisting Immunity to the Vaccine Carrier

Abstract
E1 deletion adenoviral vectors of the human serotype 5 (AdHu5) and the chimpanzee serotype 68 (AdC68) expressing the rabies virus glycoprotein (rab.gp) were tested for induction of transgene product-specific antibodies upon intranasal or oral immunization of newborn mice. Both vectors induced antibodies to rabies virus that could be detected in serum and mucosal secretions. Serum rabies virus-neutralizing antibody titers sufficed to protect neonatally vaccinated mice against a subsequent challenge with rabies virus. The efficacy of the AdHu5rab.gp vector given orally to newborn mice born to AdHu5-immune dams was not impaired by maternally transferred antibodies to the vaccine carrier.