FIG. 4.

Lysis of HIV-1-infected macrophages and CD4⁺ T cells by Nef187-203-specific cytotoxic CD4⁺ T cells. (A) Intracellular p24 antigen expression of macrophages and CD4⁺ T cells from an HLA-DRB1*0803-positive donor at day 3 postinfection. The dashed histogram represents uninfected cells, and the solid histogram represents HIV-1-infected cells. The values in each plot show the frequencies of p24 antigen-positive cells. The uninfected and HIV-1-infected macrophages and CD4⁺ T cells were then labeled with Na₂⁵¹CrO₄ and incubated with Nef187-203-specific clones for CTL assays. (B) Cytotoxic activity of three Nef187-203-specific clones against autologous B-LCLs incubated with the peptide at the indicated concentrations. The cells were tested at an effector-to-target (E/T) ratio of 5:1. (C) Ability of Nef187-203-specific clones to lyse HIV-1-infected or uninfected macrophages (Mφ) and CD4⁺ T cells. The cells were tested at the indicated E/T ratios by using the standard ⁵¹Cr assay. Values represent averages ± standard deviations (error bars) of results from the assays of the three Nef187-203-specific clones.