Characterization of the structural proteins of hepatitis C virus expressed by an adenovirus recombinant

Human adenoviruses have been used for mammalian expression vectors and recombinant vaccines for heterologous antigens. We constructed and characterized an infectious adenovirus recombinant containing core-E1-E2 genes of hepatitis C virus (HCV). The core protein was produced mainly during the early phase of viral infection. Expression of HCV E1 and E2 envelope proteins was detected by an immunoprecipitation with HCV-positive patient's sera. The purified E1 and E2 proteins appeared to be composed of mainly a heterodimeric form via noncovalent interaction, as previously observed in other mammalian expression systems. A small portion of E1 and E2 monomers as well as E1E2 aggregates by interdisulfide linkage were detected. Apparently heterodimeric E1E2 complexes were serologically reactive. The results suggest that adenovirus is an useful HCV antigen-expression vector.