FIG 5.

MLN4924 inhibits Vpu-mediated downmodulation of CD4 and increases the surface expression of a CD4-induced Env epitope in CEM.NKR.luc cells. (A) CEM.NKR.luc cells were infected with wild-type or mutant HIV-1 as indicated. Four days later, the cells were incubated with either DMSO alone or 200 nM MLN4924 for 12 h, and surface CD4, BST2, and Env expression was determined by flow cytometry, gating on p24-positive cells. (B) Subset of histograms from panel A regrouped to show the effects of Nef and Vpu in the absence of MLN4924. (C) For two independent experiments, the results for one of which are shown in panels A and B, the mean fluorescence intensities for CD4, BST2, A32, and HIV-IgG were averaged and normalized to ΔvpuΔnef in the absence of MLN4924, which was set to 100%. −, open bars indicate the absence of MLN4924; +, filled bars indicate treatment with MLN4924. Error bars indicate ±average deviations.