Protein expression analysis of normal and NPC-deficient cells after HIV-1 infection. Cells were uninfected or infected with VSVG-HIV-1 and harvested 96 h post-infection. (A) NPC2, NPC1, and β-actin protein expression was detected via Western blotting in uninfected and infected cells. Gag expression was also detected in the infected cells. (B) At 96 h post infection, cells were fixed and stained with KC57-FITC (anti-Gag). Flow cytometry was performed and mean fluorescence intensity (MFI) is shown.