Tumoristatic activity of human DCs pretreated with LPS.

DCs at 2 × 10⁶ cells/mL were cultured in polypropylene tubes with or without LPS at 5 μg/mL. At 24 hours, DCs were washed 3 times and plated with indicated tumor cells at 1 × 10⁴ cells/well in 96-well plates at an E-to-T ratio of 5:1. The cultures were pulsed with³H-TdR. Proliferation was measured at 48 hours after addition of tumor cells. The results are presented as the mean ± SD of triplicate wells. The results of 2 representative experiments using DC from different donors is shown. *P < .05 compared with DCs cultured with medium.