FIG 2.

Impact of the molecular strategy for LucR element insertion on Nef expression from reporter HIV-1 and CD4 downregulation. Cell surface staining with anti-CD4 antibody OKT4 of primary CD4⁺ T cells either mock infected or infected with IMCs expressing different Env strains (CH058, CH040, CH077, CH0505, YU2, SF162, and BaL) and expressing or not the LucR reporter. (A to C) Histograms depicting representative CD4 stainings (A) and the MFI of the infected (p24⁺) population obtained in at least 5 independent experiments (B and C). (D) Nef expression from cells infected with the indicated parental and LucR IMCs encoding CH058 or CH077 Env was monitored by Western blotting with antibodies directed against CA/p24 (for normalization) and Nef. (E) Nef expression levels correlated with detection of CD4 at the surfaces of infected (p24⁺) cells using a Pearson correlation test. The data are shown as means and standard errors of the mean (SEM). Statistical significance was tested using an unpaired t test (*, P < 0.05; **, P < 0.01; ****, P < 0.0001).