FIG. 4.

Production of IL-12 by bone marrow-derived DCs or Mφs alone or by DC/UV-EB or Mφ/UV-EB. (A) Time course of IL-12 production. Bone marrow-derived cells were stimulated in vitro with UV-EBs for various periods as indicated along the x axis, and the supernatants were collected at each time point for evaluation of the IL-12 concentration. (B) Duration of IL-12 production by DCs stimulated in vitro with UV-EBs for 18 h. Supernatant collected from the 18-h-stimulated culture was designated the day-0 sample. After excess chlamydial organisms were washed off and the stimulated cells were cultured again in fresh medium for another 24 h, the supernatant was collected as the day-1 sample. After washing, culturing of the cells was continued as described in Materials and Methods. Three to five separate experiments were performed; each experiment was performed in triplicate.