IFNγ induces the expression of IRF8 and PU.1. Quantitative PCR analysis of expression levels of PU.1 (A) and IRF8 (B) in purified GMPs from naive mice and from mice 8 days after LCMV infection. Expression is relative to the levels in naive WT GMPs. Relative expression of PU.1 (C) and IRF8 (D) in WT GMPs after in vitro stimulation with IFNγ. Expression is relative to the levels in unstimulated GMPs. Data in panels A and B represent means ± SD from 3 independent experiments with 2 mice per group; data in panels C and D represent means ± SD from triplicate stimulations measured in duplicate. *P < .05; **P < .01; ***P < .001.