Effects of B-CD or SMase treatment of cells on HCV infectivity. Huh-7 cells were either left untreated or treated with B-CD at 0.1, 1, or 5 mg/ml (A) or with SMase at 0.1, 1, or 10 U/ml (B) prior to HCVcc infection. Intracellular core levels were quantitated 72 h p.i. Data are means from four independent experiments. Error bars, standard deviations.