Fig. 5.

Particulate fractions derived from killed K562 cells stimulate DCs to secrete IL-12p40. Monocyte-derived DCs were cultured for 48 h with non-injured, killed K562 cells, or with the particulate (p) or soluble (s/n) fractions of heat or freeze/thaw-killed cells (Materials and methods). Error bars represent duplicates of culture. In five experiments with different donors, particulate fractions of injured cells stimulated more IL-12p40 secretion than their soluble fractions (for heat-killed K562 cells P = 0·04, for freeze/thaw-killed K562 cells P = 0·043).