Fig. 4

KYN or KYNA promotes TSG-6 production in hMuSCs. a hMuSCs were treated with IFN-γ (10 ng/ml) and TNF-α (10 ng/ml) for 24 h, and the expression levels of main enzymes in kynurenine pathway were examined by real-time PCR. b KYN and KYNA concentrations in the supernatant of hMuSCs treated with IFN-γ (10 ng/ml) and TNF-α (10 ng/ml) for 24 h were measured by HPLC-MS. c, d hMuSCs were treated with IFN-γ (1 ng/ml) and TNF-α (10 ng/ml) and were added DMSO, KYN (400 μM), or KYNA (200 μM). After 24 h, these cells were examined for the expression of TSG-6 mRNA (left) and protein (right). Results were shown as mean ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001; ns, no significance