Figure 2.

Specific binding antibody titer. a) Vaccine inoculation schedule of mice. All groups were inoculated with DNA vaccine at Weeks 0, 2, 4 and 6 and then sacrificed at Week 9 to assess cellular and humoral immune responses. b, c & d) The specific binding antibody titer induced by DNA vaccines. Antibody reactivity was then determined by measuring the optical density (OD) at 492 nm, and endpoint titers were determined by the last dilution whose OD was >two-times than that at the average corresponding dilution of mice sera immunized with SV1.0. The Y value is the log value of the endpoint titers. The significance of differences among the different groups was calculated using a statistical method of one-way analysis of variance (GraphPad prism4.0); * p < 0.05, ** p < 0.01. We obtained data from three experiments using fresh sera.