Figure 1. Toxicity of Kae and Dai on BHK21 cells and their effects on JEV infection.

(A) Growth inhibition curve of Kae on BHK21 cells for 72 h. CC₅₀ was 230 µM. (B) Growth inhibition curve of Dai on BHK21 cells for 72 h. CC₅₀ was 270 µM. (C) Anti-JEV effects of Kae and Dai when cells were pretreated for 2 h before infection with 0.1 MOI JEV for 72 h. EC₅₀ for Kae and Dai at 72 h were 12.6 and 25.9 µM, respectively. (D) Comparison of anti-JEV effects of combination treatment with Kae and Dai when cells received combined pretreatment for 2 h, and were then infected with 0.1 MOI JEV for 72 h. (E) Anti-JEV effects of Kae and Dai when cells were infected with 0.1 MOI JEV for 2 h and then treated with Kae or Dai for 72 h. EC₅₀ was 21.5 µM for Kae and 40.4 µM for Dai. (F) Comparison of anti-JEV effects of combination treatment with Kae and Dai when cells were infected with 0.1 MOI JEV for 2 h followed by combination treatment for 72 h. The data represent the means for five replicate samples of three separate experiments. Kae (black square) or Dai (black circle).