Figure 1.
Optimal culture conditions for natural killer (NK) cell-mediated dendritic cell (DC) maturation. Immature DCs (iDCs) were cocultured with NK cells or separated from NK cells by transwell membranes in the presence of IL-2 (DCNK+IL-2) or IL-2 and poly(I:C) (DCNK+IL-2+I:C). (a) DC maturation was determined by measuring CD86 and CD83 expression by flow cytometry. DCs in direct coculture expressed high levels of CD86 and CD83. Shown are representative histograms demonstrating the expression of surface markers (shaded histogram) compared with isotype controls (open histogram). These figures are representative of three independent experiments. (b) Cytokine production was measured in the supernatants from cultures of iDCs (gray bars) and from cocultures of DCs and NK cells in indirect contact (white bars) or direct contact (black bars). IL-12p40 levels were significantly higher in supernatants from cells cocultured in direct contact (*P<0.05). (c) To assess IL-12p70 production, all DCs were further stimulated with CD40L-transfected J558 cells. IL-12p70 levels were significantly higher in supernatants from cells cocultured in direct contact (*P<0.05).