Figure 4.

Specific humoral anti-FMDV responses in VLP/Adenovirus prime boost vaccination regimes. In (A), a schematic view of both regimes used is shown. Groups of ten C57BL/6 mice were vaccinated using sequential adenovirus and VLP combinations. In scheme 1, animals were vaccinated at day 0 and day 21 with 100 µg of purified VP60_CS8c1 VLP and at day 28 with a single subcutaneous inoculation of 10⁹ IFU of rhAdV5-3D. In scheme 2, rhAdV5-3D was inoculated at day 0, and VP60_CS8c1 at days 8 and 28. Samples were taken on day 35 in both cases from groups of five animals, sparing the remaining five for the challenge experiment. Corresponding control groups using either rhAd5-lacZ or VP60_OUK VLP or PBS-inoculated animals were included. IgG anti-VP60 antibody titers in sera at day 35 (B) or anti FMDV_CS8c1 B-epitope peptide titers at days 21 and 35 (C) for the indicated groups as determined by ELISA. In (B) mean + SD for each group is shown. In (C), data from individual samples assayed in triplicate is shown and horizontal bars indicate mean titer for each group. In (D), FMDV_CS8c1-specific mean-neutralizing antibody titers were calculated by microneutralization assays on BHK-21 cells for each animal in the group and mean titer is indicated by horizontal bars. Significant differences among groups are indicated by **** (p < 0.0001), ns: no significant differences.