Fig 4.

Dose-response curves of four antiretrovirals for cell-free HIV and HIV-infected effector cells using Gag p24 measurement on R5M and X4M cells. One hundred TCID₅₀ of resting PBMC (blue) or activated PBMC (red) was added to either R5M or X4M target cells and incubated for 7 days in the presence of a serial dilution of the respective compound. Cumulative Gag p24 was subsequently measured in the supernatant of R5M cocultures to assess effector plus target cell infection (full regression lines) or in the supernatants of X4M cocultures to assess ongoing infection in the effector cells (dashed regression lines) and plotted against the compound concentrations. Nonlinear regression was performed on data from one representative experiment (GraphPad Prism). As similar results were obtained for the other eight compounds, only one representative inhibitor of each antiretroviral class is depicted. OD, optical density.