Figure 4.

Nitric oxide (NO) and transforming growth factor-β1 (TGF-β1) production by mature DCs (mDCs) from interferon-γ^−/− (IFN-γ^−/−), interleukin (IL)-12/IL-23^−/− IFN-γ^−/− and C57BL/6 mice. Bone marrow-derived DCs were cultured in the presence of lipopolysaccharide (LPS) (1 µg/ml) for 18 hr. After washing, the cells (10⁶) were further incubated for 48 hr, with or without recombinant IFN-γ (rIFN-γ) (2·5 ng/ml).(a)NO was quantified in culture supernatants by using the Griess reaction. Experiments were repeated four times, with the same pattern of results obtained on each occasion.(b)TGF-β1 was quantified in culture supernatants by enzyme-linked immunosorbent assay (ELISA). Experiments were repeated twice, with the same pattern of results obtained on each occasion. Data represent the mean values ± standard deviation (SD) of a representative experiment. SD values were calculated from triplicate samples. *P < 0·05 versus C57BL/6 mDCs. **P < 0·05 versus IFN-γ^−/− mDCs.