Effect of GM-CSF and IL-4 on IL-12p70 expression in DCs treated with tumor cell lysates. (A-C) IL-12p70 and IL-10 expression in DCs pulsed with CMQ-treated TCLs under different culture conditions. After harvesting, DCs were incubated in three kinds of culture conditions with or without GM-CSF (20 ng/ml) plus IL-4 (20 ng/ml), and were treated as follows: vehicle (imDC), LPS (maDC), TCL plus LPS for 24 h (CTCL-CMQ) or TCL for 12 h and then LPS for 24 h (TCL-CMQ) as described in Materials and Methods. The level of IL-12p70 released into supernatants of test DC cultures was assayed by ELISA. Statistical difference among test groups was analyzed by Student's t-test. P values less than 0.05 were considered statistically significant (*, P < 0.05; **, P < 0.01; ***, P < 0.001 versus the maDC group).