MSCs and TSG-6 suppress LPS-induced pro-inflammation gene expression of microglia. BV2 cells were co-cultured with MSCs, TSG-6-siMSCs, or control-siMSCs activated by TNF-α and different concentration of rmTSG-6 (1 ng/ml, 10 ng/ml, 100 ng/ml) and treated with or without LPS (100 ng/ml) for 6 hours. (A-D), mRNA levels of TNF-α, IL-1β, IL-6, and iNOS were measured by qRT-PCR analyses and quantified as fold induction over the levels in unstimulated control cells. All transcriptional levels were normalized to GAPDH mRNA levels and determined by the 2-ΔΔCt method. Values in the bar graphs are presented as mean ± SD. n = 3; *P <0.05; significantly different from LPS-treated cells. Abbreviations: TSG-6-siMSCs, MSCs transfected with TSG-6 siRNA; Ctrl(control)-siMSCs, MSCs transfected with control siRNA; LPS, lipopolysaccharide; iNOS, induced nitric oxide synthase.