The protein level of ApoB was decreased in HCV-infected cells.

(A) Huh-7 cells were infected with HCV at different MOIs. After 96 hours, the protein levels of ApoB and HCV core proteins were analyzed by western blotting. Actin was used as the loading control. (B) Huh-7 cells were infected with HCV (MOI = 1). The protein levels of ApoB and HCV core proteins were analyzed by western blotting at the indicated timepoints after infection. Actin was used as the loading control. (C) The protein level of ApoB in culture supernatants of mock-infected, HCV-infected (MOI = 1) Huh-7 cells or ApoB^-/- cells was analyzed by western blotting at 4 days post infection. Albumin was used as the loading control. (D) qPCR analysis of the mRNA level of ApoB in cells in B. The results are presented as fold changes in the mRNA level of ApoB relative to that of GAPDH. (E) Immunostaining was performed with anti-ApoB and anti-core antibodies in mock- or HCV-infected (MOI = 1) Huh-7 cells at 4 days post infection. LDs were stained with BODIPY 493/503. Nuclei were stained with DAPI. Fluorescence signals were visualized by laser confocal microscopy. LD, lipid droplet. (F) Flow cytometric analysis was performed in ApoB^-/- cells and mock- or HCV-infected (MOI = 0.5) cells at 4 days post infection. The staining of ApoB, core, and LDs is described in the Methods. The data are shown as the means ± SDs of n = 3 biological repeats. The statistical significance was determined by unpaired two-sided Student’s t-tests. n.s., not significant. ** P < 0.01.