Figure 3.

T cell-IKKβ activity is required for anti-tumor effector function. CD4-cre x IKKβ^fl/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 (CFSE^low) or without (CFSE^high) 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.