IL-27 enhances macrophage APOBEC RNA expression. Monocyte-derived macrophages were treated 18 to 24 hours with IL-27 at 100 ng/mL or IFN-α at 10 ng/mL. Cells were lysed and processed for RNA following QIAGEN's RNeasy protocol, and gene transcription was analyzed by real-time PCR for (A) APOBEC3G (n = 3) and (B) APOBEC3A (n = 5). GAPDH was used as normalization control. Data were analyzed using the 2^−ΔΔct method and results reported as fold increase (*P < .05; **P < .005). (C) IL-27 (5-200 ng/mL) was added to macrophage cultures for 24 hours and RNA processed for real-time PCR with APOBEC3A primers (n = 4). Inset: IL-27 (50 ng/mL) was added to macrophage cultures for 24 hours and indicated members of APOBEC family expression profiles determined by RT-PCR (n = 2). (D) Kinetics (30 minutes to 24 hours) of IL-27 (0-100 ng/mL) induction of APOBEC3A expression as determined by real time PCR (n = 3). Inset: IL-27 at indicated concentrations was added to macrophage cultures for 30 minutes, and phospho-STAT1 and total STAT were monitored by Western blot.