Fig. 1

ERT activity comparison between HIV-1 and HIV-2 produced from human primary monocyte-derived macrophages and activated CD4 + T cells. a Three RT product regions (early, middle and late) of HIV-1 and HIV-2 genomes used for measuring viral endogenous reverse transcription (ERT) activity. b–d ERT activities of HIV-1 89.6 and HIV-2 Rod10 produced from macrophages. Human primary monocyte derived macrophages from 5 healthy donors were infected with HIV-1 89.6 (red line) and HIV-2 Rod10 (black line) in triplicates, and the remaining uninfected viruses were extensively washed at 9 h post infection. The media containing the produced viruses were collected at days 2, 3 and 4 post infection, and the total viral nucleic acids of the produced viral particles were extracted for the Q-RT PCR (for RNA + DNA) and Q-PCR (for DNA only) for the early (b), middle (c), and late regions (d) of the viral genomes. ERT activity assay was determined in triplicates by the ratio between DNA copy number and (RNA + DNA) copy number in the produced viral particles. Fold differences between ERT activities of HIV-1 89.6 (1 ×) and HIV-2 Rod10 were calculated. e ERT activity of HIV-1 89.6 and HIV-2 Rod10 produced from activated CD4 + T cells isolated from the same donors. ERT assay was conducted for the early region with the viruses produced up to 3 days. 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; ****P < 0.0001