Effects of dexamethasone on NF-AT, AP-1, NF-κB, and Oct-1 binding activities. T-cell clones (YA5) were stimulated with immobilized anti-CD3 MoAb or rIL-2 (100 U/mL) for 2 hours. Dexamethasone (1 μmol/L) was added to some cultures throughout the culture period, as indicated. Nuclear proteins were then extracted and DNA binding activity was measured by EMSA. Arrows indicate specific binding to NF-AT (A), AP-1 (B), NF-κB (C), and Oct-1 (D) oligonucleotides.