FIGURE 4.

Defective IL-2 production in TNFR^Δ/Δ CD4⁺ T cells. IL-2 production in naïve WT (●) or TNFR^Δ/Δ (○) CD4⁺ T cells was measured by ELISA (A) or cytokine capture (B, C) at different times after α-TCR-β + α-CD28 stimulation. Data shown are from three separate experiments in triplicate; bar indicates geometric mean. D, CD4⁺ FACS-sorted WT or TNFR^Δ/Δ T cells were stimulated with α-TCR-β + α-CD28 for 0, 6, 18, or 48 h; IL-2 production was quantified using cytokine capture. Data are representative of three separate experiments. Naïve (E) or Pre-Ac (F) WT or TNFR^Δ/Δ CD4⁺ T cells were FACS purified, stimulated with α-TCR-β + α-CD28 for the times indicated, lysed, and analyzed for steady-state c-rel mRNA using qPCR. The data are normalized to GAPDH and expressed as fold induction (mean ± SEM) relative to unstimulated naïve WT and are from three separate experiments. G, ChIP analyses to determine c-Rel association with the Il2 promoter. MNase digested nuclei were obtained from WT or TNFR^Δ/Δ CD4⁺ T cells that had been stimulated with α-TCR-β + α-CD28 for the times indicated. Data are expressed as fold induction relative to unstimulated naïve cells.