Fig. 1

Replication capacities of pBS-BFV-B and pBS-BFV-Y. a BFVL cells (8 × 10⁴) were seeded in 12-well plates. After 24 h, 1 μg pBS-BFV DNA together with 50 ng pCMV-β-gal were transfected into BFVL cells, and luciferase activity was measured 48 h later. Relative luciferase activities (Rel. Luc. Act.) are shown. b HEK293T cells (2.5 × 10⁵) were transfected with 1 μg pBS-BFV-B, pBS-BFV-Y or empty vector pBS together with reporter plasmids, 20 ng pBFV-LTR-Luc and 10 ng pCMV-β-gal. Forty-eight hours later, the cells were harvested and analyzed using a luciferase activity assay. c Cell lysates from b were harvested for Western blotting using indicated antibodies. d BFVL cells (8 × 10⁴) were transfected with 1 μg pBS-BFV-B, pBS-BFV-Y or empty vector pBS together with 50 ng pCMV-β-gal. Forty-eight hours later, the cells were harvested and analyzed using a luciferase activity assay. e Cf2Th cells (1.5 × 10⁵) were transfected with 2 μg pBS, pBS-BFV-Y or pBS-BFV-B. Seventy-two hours later, syncytium was detected in the pBS-BFV-B-transfected Cf2Th cells (white arrows). Luciferase activities shown are averages from three independent experiments. Error bars indicate standard deviations (SD). *P < 0.05 (unpaired t test), **P < 0.01 (unpaired t test)