Fig. 3

ERT activity comparison between HIV-1 89.6 viruses produced during long-term culture of macrophages with multiple treatments of Vpx (−) and Vpx (+) VLPs. Primary macrophages were pre-treated with Vpx (−) or Vpx (+) VLPs for 24 h, and then infected with an equal p24 level of dual tropic HIV-1 89.6 in triplicates. The remaining uninfected viruses were washed at 9 h post infection. The infected macrophages were cultured for 10 days post infection. During the 10-day culture, the cells were repeatedly treated with Vpx (−) or Vpx (+) VLPs in every 4 days (see black arrows). The produced viruses were harvested at every 2 days, and total viral nucleic acids were extracted and used for measuring the ERT activity of the viral particles produced from Vpx (−) (red line) and Vpx (+) (blue line) VLP treated macrophages for a early, b middle, and c late RT products. The data are the mean of three independent experiments with qPCR performed in duplicate, and error bars represent the standard error of the mean. *P < 0.05; **P < 0.01; ***P < 0.001