Effects of gene-specific siRNA knockdown on viral infectivity.

<p>(A) HT1080 cells were transfected twice with 120 nM control siRNA (Lanes 1) or specific siRNA (Lanes 2). 1^st siRNA transfection was performed at time 0 and 2^nd siRNA transfection at 24 h. At 24 h after the 2^nd transfection, half of the cells were infected with virus and the other half were analyzed by immunoblot for each specific protein (top panels) and GAPDH (bottom panels). (B) Culture supernatant was harvested at 48 h after infection and used to infect FAB cells to measure infectious titers. Relative infectivity of viruses derived from cells transfected with specific siRNA compared to those with control siRNA. Means and standard errors from at least four separate experiments are shown.