FIG. 4.

Effects of MXF on the kinetics of LPS-PMA-induced degradation of I-κBα in THP-1 cells. (A) Time-dependent studies. THP-1 cells were preincubated in serum-free medium and then treated with LPS-PMA, as indicated. (B) The cells were preincubated in serum-free medium in the absence or presence of 5, 10, or 20 μg of MXF per ml and then treated with LPS-PMA for 15 min. The cytoplasmic extracts were prepared and assayed by WB analysis for I-κBα (upper blots in panels A and B) and actin (lower blots in panels A and B).