Poly(I:C) (Sigma, USA) was dissolved in diethyl pyrocarbonate
(DEPC)-treated water at a concentration of 1 mg mL1 immediately
before use. VHSV was suspended in MEM10 at 107
, 106
, and 105
TCID50 mL1 the previous day and stored at 4 C. Formalin-treated
VHSV (FT VHSV) was prepared as described elsewhere [31]. Briefly,
the virus was suspended at 107
, 106
, and 105 TCID50 mL1 in MEM10,
followed by the addition of formalin (0.1% v/v) and briefly mixed by
vigorous vortexing for 30 s. The mixture was incubated at 4 C for
1 d (vaccine trial I) or 7 d (vaccine trial II) without shaking.