Fig. 7

BST-2 down-regulation by Vpu and E proteins. HEK293 cells were co-transfected with either the empty pcDNA3.1( +) vector, the pcDNA3.1( +) vector expressing the HIV-1 Vpu protein, or each of the four E proteins, and a vector expressing human BST-2 protein. A At 48 h, the cells were removed by treatment with EDTA/EGTA, stained with a mouse monoclonal antibody directed against BST-2, and subjected to flow cytometric analysis using a BD LSR II flow cytometer. The fluorescent intensities are on the x-axis. B Median and mean fluorescent intensities of the BST-2 on the cells from Panel A. C Aliquots of cells from the same co-transfection were also analyzed for protein expression by immunoblots using antibodies directed against the HA-tag (E proteins and Vpu) to monitor expression