Figure 2. Protection of VP2, VP7 and NS1 vaccinated IFNAR^(−/−) mice against a lethal homologous BTV-4 challenge.

Mice (8 weeks old, 6 per group) were immunized twice by heterologous prime boost vaccination with pcDNA3 and rMVA expressing VP2/VP7/NS1 (▪), VP2/VP7 (▴), or NS1 (•) BTV-4 proteins (immunized, black line) or pcDNA3 and MVA (♦) (non-immunized, dotted line), administered 2 weeks apart. Two weeks after immunization all mice were intravenously inoculated with 10³ PFUs of BTV-4 (lethal dose). Survival rates of immunized and non-immunized IFNAR^(−/−) mice after inoculation with BTV-4. The mice were observed every 24 h for 12 days.