FIGURE 3.

Distribution of CD8⁺ memory subpopulations between total memory cells and HIV-specific cells. PBMC from HIV-infected individuals (n = 16) at 6–9 mo postinfection were stimulated with Gag, Nef, Pol, and Env peptide pools and the frequency of CD8⁺ memory subsets was quantified from IFN-γ-producing T cells (IFN-γ⁺) and total memory CD8⁺ T cells (total memory). A, Representative density and overlay dot plots of memory subsets in total CD8⁺ T cells (density) and Gag-specific IFN-γ⁺ CD8⁺ T cells (red dots) defined according to CD45RO, CD27, and CCR7 expression levels. Left panels, CD45RO⁺ memory CD8⁺ T cells at 6–9 mo postinfection in three individuals (CAP084, CAP228, and CAP045) having a low viral set point (SP) at 12 mo postinfection and three individuals (CAP256, CAP174, and CAP210) with high viral set point at 12 mo postinfection. Right panels, CD45RO⁻ memory CD8⁺ T cells in low and high viral set point individuals. Numbers in the quadrants correspond to the proportion of each memory subset in total memory CD8⁺ T cells (in black), expressed as a percentage of total memory cells, while the proportion of IFN-γ⁺CD8⁺ T cells are in red. Patient identification numbers and viral set point (SP) at 12 mo are shown. B, T_CM, T_TM, T_Int, T_EM, and T_Eff memory subsets expressed as a percentage of total memory cells. For total memory, each datum point represents a study individual, and for IFN-γ⁺ cells, each datum point represents a positive HIV-specific response. The median is shown as a horizontal bar. Statistical comparisons were performed using Krukal-Wallis ANOVA and multiple comparisons using Dunn’s test.