Hepatitis C virus (HCV) core protein enhances the immunogenicity of a co-delivered DNA vaccine encoding HCV structural antigens in mice.

In the present study, recombinant HCV (hepatitis C virus) core proteins enhanced the immune response elicited by a co-delivered DNA vaccine encoding HCV core and envelope proteins. A mixture of the plasmid pIDKE2 and Co.173, a protein comprising the first 173 amino acids of HCV core, in particular induces a strong humoral response, including antibodies that recognized peptides representing hypervariable region I from different viral isolates.

Immunization with a DNA vaccine encoding the hepatitis-C-virus structural antigens elicits a specific immune response against the capsid and envelope proteins in rabbits and Macaca irus (crab-eating macaque monkeys).

In the present study, we evaluated the capability of the plasmid pIDKE2, encoding the HCV (hepatitis C virus) structural proteins Core, E1 and E2, to induce immune response against HCV antigens after injection into rabbits and Macaca irus (crab-eating macaque). Animals were immunized intramuscularly with different amounts of plasmid on weeks 0, 3 and 8. Monkeys received a booster dose on week 46.

Enhancement of the immune response generated against hepatitis C virus envelope proteins after DNA vaccination with polyprotein-encoding plasmids.

Plasmids expressing variants of the hepatitis C virus (HCV) core, E1 and E2 proteins individually or as polyproteins were administered to BALB/c mice. All plasmids induced a detectable and specific antibody response. Antibody titres against core, E1 and E2 proteins, 19 weeks after primary immunization, ranged from 1:50 to 1:4500 depending on the inoculated plasmid and the HCV antigen evaluated.