[Role of macrophage migration inhibitory factor in mice with sepsis and after effect of its intervention].

Objective: To investigate the expression profile of macrophage migration inhibitory factor (MIF) in serum and lung tissues of mice with sepsis, and to explore the effect of MIF antagonist ISO-1 on sepsis in a murine sepsis model.

Methods: Sepsis was reproduced in 40 mice by cecal ligation and puncture (CLP). Heart blood was obtained from 8 mice each at 12, 24, 36, 48 hours after CLP. The content of MIF in serum was determined by enzyme linked immunosorbent assay (ELISA). MIF mRNA and protein expressions in lung tissues of septic mice were assessed by reverse transcription-polymerase chain reaction (RT-PCR) or Western blotting. Another group of 40 mice were selected to investigate the role and the impact of MIF antagonist ISO-1 in septic mice.

Results: The content of MIF in serum was higher in septic mice than that in sham operation group, and it peaked at 36 hours, and decreased at 48 hours, but still higher than that in sham operation group (all P<0.01). The MIF mRNA and protein expression in lung tissues of septic mice were higher than those in sham operation group, beginning at 12 hours, and peaked at 48 hours (P<0.05 or P<0.01). ISO-1, which was the antagonist of MIF, could elevate the surviving rate of animals with sepsis [60% (12/20) vs. 25% (5/20), P<0.05].

Conclusion: MIF plays a role as a late mediator in sepsis, with a high expression of MIF in serum and lung tissue. ISO-1 can elevate the surviving rate in murine model of sepsis. It is concluded that MIF could be taken as a potential target of treatment of sepsis.