FIG 3.

Memory phenotype of vaccine-induced CD8⁺ T cells in PBMC. RM memory T cells can be classified into three subsets based on the differential expression of the cell surface molecules CD28 and CCR7: fully differentiated effector memory (T_EM2; CD28⁻ CCR7⁻), transitional memory (T_EM1; CD28⁺ CCR7⁻), and central memory (T_CM; CD28⁺ CCR7⁺). Based on the expression of these two markers, the memory phenotype of vaccine-induced CD8⁺ T cells against Vif RL8 (A), Vif RL9 (B), and Nef RL10 (C) in PBMC was delineated at week 37 after rAd5 prime. The panels on the left show the percentages of MHC-I tetramer⁺ CD8⁺ T cells that display each of the three memory signatures. This flow cytometric analysis also evaluated the intracellular expression of the cytotoxicity-associated molecule granzyme B (Gzm B) by each MHC-I tetramer⁺ CD8⁺ T-cell population, as shown in the panels on the right. Lines represent means. The P values were determined by repeated-measurement ANOVA. Vaccinees are color coded as described in the legend of Fig. 2. Data from monkey r08038 were not available for this analysis.