Abstract: AIM: To investigate the expression of MIF mRNA and protein in cultural human macrophages induced by different lipoproteins.METHODS: 28sc human macrophage cell lines were grown in RPMI-1640 medium containing 1×105 U°L^-1 penicillin, 100 mg°L^-1 streptomycin, 10% FBS at 37 ℃ and 5% CO₂.The concentrations of cells were adjusted as 10×10⁴ ml-1, and then macrophages were inoculated in 6 wells plate. Different lipoproteins with a final concentration as 150 mg°L^-1 were added respectively in each well.After culture 24 h together, the expression of MIF mRNA and protein were detected by RT-PCR and ELISA methods.RESULTS: The MIF mRNA and protein were expressed in macrophage.LDL, Ox-LDL, cholesterol and TG can significantly increased the expression of MIF mRNA and protein in macrophage compared with the control group(P<0.05).However, HDL and VLDL showed no effect on the expression of MIF mRNA and protein in macrophage (P>0.05).CONCLUSION: Different lipid including LDL, Ox-LDL, cholesterol and TG can up-regulate MIF mRNA and protein expression in macrophage.It suggests that MIF may involve in the progress of atherosclerosis.

Key words: lipoproteins, macrophage, migration, inhibitory factor, atherosclerosis, cell culture, RT-PCR, ELISA