Fig 7. Flow cytometry of E2 peptides binding to human and rat cells and inhibitions of anti-CD81 antibody/cell binding by E2 peptides.

(A) and (B) show the fluorescence intensity of Huh-7 cells treated with fluorescent p_E2-site1 (E2-s1) and p_E2-site2 (E2-s2), respectively, at different concentrations; (C) and (D) are the fluorescence intensity measurements of the rat PC12 cells treated with fluorescent p_E2-site1 or p_E2-site2, respectively; and (E) and (F) are the inhibitions of fluorescent anti-CD81 antibodies targeting Huh 7 cells by HCV E2 peptides. In this experiment, untreated cells were used as negative controls, and the cells treated with fluorescent-labelled anti-CD81 antibodies were used as positive controls and set as 100% binding. p_m_E2-site1 (m-E2-s1) and p_m_E2-site2 (m-E2-s2) in (A), (B), (C) and (D) are mutant peptides of p_E2-site1 and p_E2-site2 indicated in S1 Table.