T cell-IKKβ activity is required for anti-tumor effector function. CD4-cre x IKKβfl/fl and littermate control mice were subcutaneously injected with 106 MC57-SIY tumor cells and sacrificed 7 days later. a) Splenocytes were restimulated in vitro with γ-irradiated MC57-SIY tumor cells, and frequency of tumor-specific IFN-γ-secreting cells was determined by ELISpot. b) Mean spot size (from a) was used to evaluate amount of IFN-γ secretion on a per-cell basis. Results are representative of 2 experiments. c) Quantification of soluble IFN-γ and TNF-α from CD8+ splenocytes restimulated in vitro with γ-irradiated MC57-SIY tumor cells or PMA + ionomycin, as assessed by cytokine bead array. d) Mice bearing MC57-SIY tumors for 7 days were injected with a 1:1 ratio of CFSE-labeled cells loaded with (CFSElow) or without (CFSEhigh) SIY peptide. Eighteen hours later, mice were sacrificed and the presence of the target cells was assessed by flow cytometry. Results are representative of at least 2 experiments. e) Specific lysis of SIY-specific cells was calculated using the ratio of the transferred populations as described in Materials and Methods. Results combine 2 independent experiments. *p < 0.05, **p < 0.01.