Figure 1.
Anti-VTT neutralizing antibody responses after the VTT vaccination. (a) A FACS-based neutralization assay was newly developed to measure the anti-VTT neutralizing antibody responses. (b) Serum samples were tested three weeks after the VTT vaccination. (c) Serum samples were tested six months after the VTT vaccination. Due to a limited amount of serum collected from each mouse, pooled sera, which contain an equal amount of serum of each vaccinated mouse in each group, were subjected to each experiment. The X-axis represents the serum dilution factor whereas the Y-axis indicates the percentage of viral inhibition. An IC50 value is a serum dilution factor which achieves 50% of viral inhibition as indicated by the dashed horizontal line. The experiment was repeated twice with similar results obtained. Placebo (no VTT) mice were tested as well.