Accumulation of CD8⁺T cells in peripheral tissues is not a consequence of local IL-15–induced expansion. (A) Frequency of T (CD3⁺) and total NK (either CD56⁺ or CD16⁺) cells relative to the frequency of B (CD20⁺) cells in the lymphocyte gate as observed in the spleen and (B) percentage of CD95⁺ memory CD4⁺ and CD8⁺ T cells in peripheral tissues at day 13 after treatment initiation. Data are expressed as in Figure 3B and tissue abbreviations are indicated as in “Isolation of MNCs from blood and tissues.” (C) Representative example of the frequency of T_CM, T_TM, and T_eff CD4⁺ (left) and CD8⁺ (right) T cells in multiple tissues, as gated on the basis of CCR7 and CD28 expression in CD95⁺ cells. Animal 395 is shown as a control and animal CJ64 as IL-15–treated. *P < .05 after Wilcoxon rank test versus sham.