Impaired IL-12 synthesis in neonatal moDCs is not overcome by exogenous IFNβ. For quantification of IL-12p35 mRNA levels, adult and cord blood moDCs were incubated with medium alone, LPS (100 ng/mL), and/or IFNβ (100 U/mL) for 6 hours. For determination of bioactive IL-12p70 levels in the supernatants by ELISA, cells were stimulated for 24 hours. Mean and SEM from 5 (RT-PCR experiments) and 10 (ELISA experiments) different donors are shown. *P < .05 and **P < .01 cord versus adult moDCs.