Human adenovirus 2 as immunogen in rabbits yields antisera with high titers of antibodies against the nonstructural 72K DNA-binding protein

Immunization in rabbits with intact, highly purified adenovirus type 2 (Ad2) virions, yielded antisera with high titers of antibodies against the 72 000 dalton DNA-binding protein (DBP). This was established by rocket immunoelectrophoresis when an anti-intact Ad2-antiserum was analyzed against fractions from an ion-exchange chromatogram of soluble antigens remaining after virus isolation from virus-infected HeLa cells. The high anti-DBP titer did not reflect the composition of the immunogen, since no DBP was detectable within virions. An antiserum raised in response to mildly disrupted virions showed no specificity against the DBP, but contained antibodies against the same structural proteins as the anti-intact Ad2-antiserum, when analyzed by the immunoblotting technique. These findings indicate that the nonpermissive rabbit as an experimental host permits early gene expression of a human adenovirus.