Previously we noticed that Arb inhibition of primary infection of Huh-7.5.1 cells with HCV (clone JFH-1) was efficient only when cells were preincubated with Arb 24 or 48h before infection [10]; in addition, inhibition of HCVpp and HApp cell entry was most efficient when Arb was pre-incubated with both viral and cell membranes [12]. This evidence concerns the gene BEST1 and infection.