Knockdown of eIF4B was achieved by transfecting MCF7 cells with eIF4B specific siRNA (Silencer® select Product # s4573 & s4574). Western blot analysis (Fig a) was performed using whole cell extracts from the MCF7 knockdown cells (Lane 3), non-specific scrambled siRNA transfected cells (Lane 2) and untransfected cells (Lane 1). The blots were probed with Anti-eIF4B Recombinant Rabbit Monoclonal Antibody (Product # 702863, 1:500 dilution) and Goat anti-Rabbit IgG (H+L) Superclonal™ Secondary Antibody, HRP conjugate (Product # A27036, 1:5000 dilution). Densitometric analysis of this Western blot is shown in histogram (Fig b). Loss of signal upon siRNA mediated knock down confirms that antibody is specific to eIF4B.