Increased proliferative capacity in DP CD4⁺CD8⁺ T cells. (A) Bar charts showing the mean BrdU⁺ proliferative responses in different T-cell subsets from different tissues. (B) Mean BrdU expression in naive (CD95⁻) and memory (CD95⁺) T-cell subsets are shown from different tissues in normal, uninfected neonates 12 to 21 days old. Each bar represents mean plus or minus SEM. Representative flow cytograms show increased proliferative capacity in DP T cells in whole blood (C) and jejunum LPLs (D). Note that memory (CD95⁺) cells have higher proliferative responses compared with naive (CD95⁻) cells. Percentages of CD95⁺ and BrdU⁺ cells are shown in each quadrant (C and D).