Figure 6.

Dominant-negative p53 inhibits enhanced activation-induced apoptosis in MIF^−/− macrophages and restores function. Peritoneal macrophages from MIF^+/+ and MIF^−/− mice were treated with or without 250 nM TAT-p53^DD for 15 min before stimulation with 10 μg/ml LPS and 100 units/ml IFN-γ for 24 h. (A) Activation induced apoptosis was assessed by fluorescent-annexin staining and fluorescence microscopy. (B) Anti-hemagglutinin (HA) immunoblot analysis of primary macrophages from MIF^+/+ and MIF^−/− mice transduced with TAT-p53^DD, demonstrating equivalent transduction efficiencies. (C) Supernatants from indicated samples were assessed for TNF-α production by ELISA. Data shown are the mean ± SD of duplicate samples and are representative of two independent experiments. *, P < 0.05 for LPS/IFN-γ/TAT-p53^DD vs. LPS/IFN-γ alone.