Elicitation of strong immune responses by a DNA vaccine expressing a secreted form of hepatitis C virus envelope protein E2 in murine and porcine animal models

Figure 2 Antibody responses to HCV E2 vaccines in mice. B6C3F1 mice were intradermally injected with pBISIA24-tPAs-tE2 three times or pBISIA24-tPAs-tE2 twice followed by subcutaneous vaccination with E2 protein formulated with CpG ODN 1826 and 10% Emulsigen at 3-wk intervals. E2-specific IgG, IgG1, and IgG2a levels were determined by ELISA assays (A). The ratios of IgG2a to IgG1 were determined (B) (P < 0.0001, vs saline).