Characterization of HCV particles produced in BE-KO cells expressing either ApoE, Erns or NS1.
(A) Experimental procedure. (B) HA-tagged complexes were immunoprecipitated from the supernatants of BE-KO cells expressing either HA-ApoE, HA-Erns, Hel, or HA-NS1 by using a control anti-IgG or anti-HA antibody. Expression of HA-ApoE, HA-Erns, Hel, or HA-NS1 in the immunoprecipitated samples was determined by immunoblotting. (C) The HCV RNA associated with ApoE, Erns, and NS1 was determined by qRT-PCR. (D) The supernatants of BE-KO cells expressing either HA-ApoE, HA-Erns, Hel, or HA-NS1 upon infection with HCV at an MOI of 1 were subjected to density gradient fractionation, and density (upper), HCV RNA levels (middle) and infectious titers (bottom) for each fraction were determined by qRT-PCR and focus forming assay, respectively. (E) Transcomplemented HCV particles (HCVtcp) were produced in BE-KO cells expressing either HA-ApoE, HA-Erns, HA-Hel or HA-NS1 at 72-h post-transfection with pCAGC-NS2/JFH1am and PHH SGR-JFH1/Gluc/NS3m. HCVtcp were inoculated into Huh7.5.1 cells, and gaussia luciferase (gLuc) activities were determined at 72-h post-infection. In all cases, asterisks indicate significant differences (* p < 0.01) versus the results of the control cells.