Additional file 1: Figure S1. Experimental layout. CB6F1 mice were immunized with 25 µg plasmid DNA each encoding Leader-Gag, Leader-Gag and Env, or Leader-Gag, Env and a cytokine. Antibody and CD8+ T cell responses were analysed two weeks after immunization. Three weeks after immunization, mice were challenged with 5000 SFFU FV, and plasma and spleen viral loads were analysed ten days and 21 days after FV infection, respectively