Unimpaired DC and macrophage function but defective Th1 differentiation in vivo in mice lacking H-ras or N-ras. (A) IL-12 production by LPS- or CpG-ODN–stimulated (48 hours) BM-derived DCs from WT, H-ras–, and N-ras–deficient mice (mean ± SD of duplicate cultures and 2 mice per group), as determined by ELISA (*P < .005 and **P < .001 vs WT). (B) BM-derived macrophages from mice of the indicated genotype were stimulated for 24 hours without or with IFN-γ (100 U/mL) or IFN-γ plus LPS (2 μg/mL), followed by assessment of NO production measured as nitrite (mean ± SD of duplicate cultures and 2 mice per group). (C) Draining LN cells (5 × 105) from L major–infected (week 3 after infection) mice of the indicated genotype were cultured with 1 × 105 WT DCs presenting SLA (12 μg/mL). Cytokine production was determined after 24 hours by intracellular cytokine staining in gated CD4+ T cells (right) or after 48 hours by ELISA (left; mean ± SD of duplicate cultures and 2 mice per group; *P < .03 vs WT). Numbers within dot plots indicate percent cells in the gated regions. (D) IL-17 response to SLA of draining LN cells from infected (weeks 1 and 3 after infection) mice, as measured by fluorescent bead assay (mean ± SD of 2 mice per group; *P < .05 vs WT).
