FIGURE 8.

Prior exposure to J1.1-derived exosomes makes naive recipient cells more susceptible to HIV-1 infection. A, CEM, U937, and THP1 cells were first incubated with Jurkat or J1.1-derived exosomes for 24 h after which they were infected with HIV-1 (89.6 virus strain (0.5 ng/p24/μl; 100 μl)). Untreated, uninfected mock cells were maintained as negative controls, and untreated, virally infected cells were maintained as positive controls. Supernatants obtained from all cells 5 days after viral infection were analyzed by RT assay. Data were obtained from three independent replicates of each sample and are representative of two completely independent experiments. Error bars show ± S.D. B, J1.1 cells were first transfected with 200 nm antagomirs to 5′ and 3′ TAR miRNA using electroporation at 230 V. Both 5′ and 3′ TAR miRNA have previously been described (siTAR1 and siTAR2 (46)). Untransfected J1.1 cells were maintained as controls. Exosomes were isolated from both untransfected and transfected J1.1 cells and used to incubate with naive U937 cells following which the cells were infected with HIV-1 (89.6 virus (0.25 ng/p24/μl; 10 μl)). RT levels were determined using supernatants obtained from all cells at 5 days after viral infection. Data are representative of three replicates of each sample; error bars show the standard deviation.