CD8A and neoplasm: Although dual anti-OX40/IL-2c therapy and IL-2c treatment alone were both associated with increased cytolytic activity by the anergic CD8 T cells (Fig. 8C), only dual therapy led to increased anti-tumor activity in vivo as shown by increased tumor regression and survival of mice harboring long-term well established (>5 wks) tumors (Figs. 8D, 8E, respectively).