FIG. 3.

Activation of JNK in LPS-PMA-stimulated THP-1 cells and effects of MXF. (A) Time-dependent studies. THP-1 cells were preincubated in serum-free medium and then exposed to LPS-PMA for the indicated times. (B) Effects of MXF on LPS-PMA-induced activation of JNK. THP-1 cells were preincubated in serum-free medium in the absence or presence of the indicated concentrations of MXF and were then treated with LPS-PMA for 60 min. The cytoplasmic extracts were prepared and subjected to Western immunoblotting with an antibody specific for the phosphorylated form of JNK (upper blots in panels A and B) or total JNK (lower blots in panels A and B). The experiment was repeated three times, and each experiment produced similar results.