Figure 3. HIV-1 PV infection suppresses expression of TRAIL decoy receptors and c-FLIP.

The virus-infected MDM were collected and stained with PE-labeled anti- DR4, -DR5, -DcR1, -DcR2 antibody and the isotype control, respectively, and followed by flow cytometry. A, representative analysis of TRAIL receptor expression on mock- or virus-infected MDM, Open histograms with solid lines, mock-infected MDM stained with PE-labeled anti-TRAIL receptor mAbs; Open histograms with dashed lines, HIV-1 PV infected MDM stained with PE-labeled anti-TRAIL receptor mAbs; shaded histograms, mock-infected MDM stained with PE-labeled isotype control. B, statistical results from 12 samples. The MFI (mean fluorescent intensities) of TRAIL receptor was assessed by flow cytometry and analyzed by a two tailed, two sample student t test (P values were indicated). C, lentivirus-mediated over-expression of DR5-delta, DcR1 and DcR2 on MDM rescued rsTRAIL- or AD5-10-induced cell death. MDM cells were infected with lentivirus vectors expressing DR5-delta, DcR1 or DcR2, respectively. HIV-1 PV-infected MDM cells were treated with 500 ng/ml of rsTRAIL or 500 ng/ml of AD5-10 for 12 hr. The cell viability was examined by MTS assay. Data are representative of three independent experiments. D, expressions of Bcl-2 family proteins and c-FLIP in HIV-1 PV-infected MDM were analyzed by Western blot assay. Data is presented as mean ± S.D. of 12 independent experiments. *, p<0.05; **, p<0.01 compared with mock or HIV-1 PV.