Objective: To construct one recombinant vaccinia virus expressing the HPV18 E6 and E7 fusion proteins as HPV18 therapeutic vaccine candidate, and test its immunogenicity.
Methods: The fusion E7E6 genes were synthesized and mutated to inactivate their oncogenic potential, and inserted into a vaccinia virus plasmid vector to construct one recombinant vaccinia virus. Finally its immunogenicity was characterized in immunized mice.
Results: One recombinant vaccinia virus expressing HPV18 E7E6 fusion proteins was constructed. Sequencing results of PCR products and Western blot tests showed that the E7E6 fusion genes were correct and expressed in CEF cells infected with the recombinant vaccinia virus. The specific antibodies against E6 and E7 proteins were elicited, however no positive responses were detected by ELISPOT in immunized mice.
Conclusions: One recombinant vaccinia virus expressing HPV18 E7E6 fusion proteins was generated and elicited specific antibodies against E6 and E7 proteins, but detected no positive cellular immune responses in immunized mice, which will provide the basis to develop the different animal model for examining the cellular immune responses of HPV18E6 and E7 proteins.