Fig. 4.

Pretreatment of cells with PERLs prevents infection by HCV and HIV. (A) Uninfected Huh7.5 cells and PBMCs were treated for 4 d before infection with Jc1 HCVcc (MOI = 0.5) or LAI HIV-1 (TCID₅₀ = 100), respectively. Viral infectivity was quantified as previously described. (B) Flow cytometric analysis of uninfected Huh7.5 cells treated for 4 d. For analysis of plasma membrane (PM) expression of viral receptors (CD-81, SR-BI, and LDLr), lipid rafts (Flot-1), and caveolae (Cav-1), cells were neither fixed nor permeabilized before detection and were gated to exclude cells positively stained with propidium iodide. Total protein expression (total) was measured after cells were fixed and permeabilized. (C) Flow cytometric analysis of uninfected CD4⁺ T cells purified from PBMCs and treated for 4 d. Both plasma membrane and total expression of Flot-1 and Cav-1 were determined as described. All flow cytometry data are presented as the geometric mean fluorescent intensity (MFI) of each sample and represent the mean and SD of triplicate samples from two independent experiments. (D) Addition of PERLs to viral stocks of HCVcc or HIV during infection periods of 1 h and 16 h, respectively. The ability of PERLs to neutralize the HCVcc and HIV infections was monitored by HCV core protein immunofluorescence assay or by p24 capture ELISA, respectively, following a 2-d incubation. Unless stated otherwise, all data represent the mean and SD of three independent experiments performed in triplicate. Data are presented in relation to the untreated control (100%), and significant differences from this value are denoted by *P < 0.05 and **P < 0.001.