HCVpp entry in receptor-complemented target cells.

aHCVpp entry of genotype 1a (H77) harbouring the GFP marker gene. (++), titres higher than 105 IU/ml; (+), titres between 103 and 105 IU/ml; (±), titres between 102 and 103 IU/ml; (−), titres lower than 102 IU/ml, which corresponds to the threshold of detection of infected cells by FACS analysis. bDetection of human CD81 using JS-81 antibody on the surface of the indicated cells by flow cytometry. (−), MFI (mean fluorescent intensity) shift of 1; (+), MFI shift between 1 and 50; (++), MFI shift over 50. cDetection of human Claudin-1 (CLDN1) in lysates of the indicated cells by immuno-blotting with mouse anti-Claudin-1 antibodies (Interchim). (−), signal intensity 5-fold lower than that detected in Huh-7 cells; (+), signal intensity between 5-fold lower and 5-fold higher than that detected in Huh-7 cells; (++), signal intensity 5-fold higher than that detected in Huh-7 cells. dDetection of human SR-B1 using the CLA-1 antibody on the surface of the indicated cells by flow cytometry. (−), MFI shift of less than 2; (±), MFI shift between 2 and 6; (+), MFI shift between 6 and 20; (++), MFI shift over 20.