Effect of FIX concentrate HT-DEFIX and its individual component proteins on transduction of HepG2 hepatocytes by AdCTL and AdKO1. (A) HepG2 cells were infected with AdCTL or AdKO1 in the absence and presence of HT-DEFIX (shown as levels of human FIX within the HT-DEFIX purification) for 3 hours in serum-free medium. Following extensive washing, cells were cultured in serum containing medium and harvested at 72 hours after transduction. ^*P < .05 versus cells without addition. (B) Human proteins (FII, AT, FIX, FX, all at physiologic levels) were used as for panel A but in place of HT-DEFIX. Representative X-Gal-stained images are shown. (C) Quantification of β-galactosidase levels 72 hours after infection in the presence of FII, AT, FIX, or FX alone or FIX and FX in combination. ^*P < .05 versus virus alone.