Figure 2.

A combination of IL-1β + IFN-γ elicits greatest synergistic upregulation of iNOS transcription in NHBE cells. Cells were exposed to combinations of TNF-α, IL-1β, and IFN-γ, all at 10 ng/ml, for 12 h. iNOS message was normalized to β-actin message. The combination of the cytokines IL-1β + IFN-γ induced the highest levels of iNOS transcription. Data are presented as mean ± SEM (n = 3). ^* Significantly greater expression compared with all other treatments (P < 0.001); ^† significantly greater than cytomix-induced expression (P < 0.01).