Fig. 6.

MIF facilitated the bacteria-induced inflammatory response and tight junction damage in hBMECs. a, b Real-time PCR determination of the expression of cytokines in response to the treatments. The MIF inhibitor ISO-1 (20 μM) significantly attenuated the PCN033- or RS218-induced production of proinflammatory cytokines. c ECIS assay showed a dose-dependent decrease of the hBMECs resistance in response to recombinant MIF protein. d Recombinant MIF protein (200 ng/mL) decreased the expression of tight junction proteins ZO-1 and occludin in hBMECs along with time. The densitometry was performed to quantitatively analyze the Western bands. e, f Western blotting and densitometry analysis showed that ISO-1 treatment partially recovered PCN033- or RS218-mediated downregulation of the tight junction proteins ZO-1 and occludin. Data were expressed as the mean ± standard deviation (mean ± SD) from three replicates or analyses (n = 3). P < 0.05 (*) was considered statistically significant; p < 0.01 (**) and p < 0.001 (***) were extremely significant