Figure 5

Murine neutralizing antibody titers were measured by the focus reduction neutralization assay (FRNT) for mice injected with WT DV2, the mutants DV2ΔLIG and DV2ΔGVII, and iodixanol in PBS-D (mock). All assays were performed on Vero cells. Individual mouse serum from each of the five mice in each experimental group was analysed and the titers shown as the reciprocal neutralization titer at 50% neutralization. Each bar represents one mouse. Mice were injected with 29 μg of each virus, equivalent to 2 × 10² ffu WT DV2, 4 × 10² ffu DV2ΔGVII, or 2.4 × 10³ ffu DV2ΔLIG. Mice injected with the mock inoculum produced no measurable neutralizing antibody.