MSCs were cultured with IFNγ (10 ng/ml) and graded concentrations of TNFα (0, 0.01, 0.1, 1, 10 ng/ml) for 24 h (A) or with IFNγ, TNFα, or their combination (each at 10 ng/ml) for the indicated times (B) and expression of IL-6 determined by real time PCR. Expression level of mRNA is presented as fold increase relative to an untreated control. Values are given as mean ± SEM of triplicates from a representative of two independent experiments.