[Synthesis of the E-antigen of the hepatitis B virus (HBeAg) in eukaryotic cells by a recombinant strain of the vaccinia virus].

The recombinant plasmids containing the gene for hepatitis B viral core-antigen with the pre-core-sequence controlled by the early-late promoter of the 7.5' K protein gene were constructed. The recombinant strains of vaccinia virus were obtained on their basis (vHBe42-1 and vHBe42-3) selectively expressing HBeAg of hepatitis B virus. The kinetics of HBeAg synthesis was studied in infected cells as well as secretion of the protein into culturing medium. Three proteins were found by blotting technique in the cells infected by vHBe42-3 that react with the specific antiserum to HBeAg and have the mol. masses 25, 22 and 17 kD. The completely processed HBeAg 17 kD was found in the culturing medium. The rabbit serums from the animals immunized by recombinant vHBe42-3 contained antibodies to HBeAg but not to HBcAg. This makes it possible to study the structural and functional organization, immunological properties and role of this antigen in pathogenesis of hepatitis virus B and to construct the specific test systems for screening HBeAg and corresponding antibodies.