Effects of ox-LDL on NF-κB and AP-1 binding activity. Macrophages were incubated for 48 h in serum-free medium without GM-CSF and subsequently treated for 2 h with copper-oxidized LDL (ox-LDL, 100 μg/mL) or LDL stored for one month at 4°C without EDTA (old LDL, 100 μg/mL). Half of the cells were simultaneously stimulated with TNF (10 ng/mL). The same nuclear extracts were analysed for NF-κB (grey bars) and AP-1 (black bars) binding activity by EMSA followed by densitometry. Data are representative of two independent experiments.