Effects of immunotherapy regimens on memory CD8 T cell expansion and function in vivo. (A) Survival after anti-CD40 and IL-2 treatment of subcutaneously implanted 3LL (left), subcutaneously implanted B16 (middle), or intravenously injected Renca (right) tumor models. (B) Total numbers of splenic CD44^highCD8⁺ T cells on day 11 of anti-CD40 and IL-2 (left) and 5 days after IL-2 and IL-12 (right) immunotherapy regimens in naive mice. (C) BrdU incorporation of CD44^highCD8⁺ T cells in response to immunotherapy. Numbers in dot plots represent percentages of CD8⁺ T cells. (D) Percentage of naive CD8⁺ T cells in wildtype and thymectomized mice 11 days after anti-CD40 and IL-2 therapy. (E) Percentage of memory CD8⁺ T cells in WT and thymectomized mice on day 11 of anti-CD40 and IL-2 treatment. (F) Expression of CD122 on CD44^high (dashed line) compared with CD44^low CD8⁺ T cells (shaded) from resting C57BL/6 mice. Data are representative of at least 3 independent experiments (*P < .05, **P < .01, ***P < .001).