CARD19 and infection: We found that when both BinCARD isoforms were simultaneously knocked down in A549 cells, the growth titers of WSN (H1N1) virus were reduced by 15- and 12-fold at 24 h post-infection (p.i.)and 8- and 4-fold at 48 h p.i. However, no significant changes in virus titers were observed between the A549 cells treated with siRNAs targeting BinCARD2 and those treated with scrambled siRNA (Fig. 1C, D).