Macrophage migration inhibition factor in peripheral blood and induced sputum in patients with COPD

BACKGROUND : Macrophage migration inhibition factor (MIF) induce many inflammatory mediators that involved in the pathogenesis of COPD, we reason that MIF may contribute to the process of COPD. OBJECTIVE :To assess the expression of MIF in peripheral blood(PB) and induced sputum(IS) of patients with COPD. METHODS :Subjects were classified into three groups: acute exacerbation of COPD(AECOPD), stable COPD(SCOPD) and normal smokers(NS). Gene expressions of MIF were measured by RT-PCR in peripheral blood mononuclear cells (PBMC), concentrations of MIF were measured in plasma using ELISA. Use Flow cytometry to count the percentage of MIF-expressing T cells (CD8 + or CD4 + ) in PB and IS . RESULTS :The percentage of MIF-expressing T cells was significantly increased in both PB and IS of AECOPD as compared with SCOPD and NS;but only MIF + CD8 + T% in IS from SCOPD was also increased compared with NS:MIF + CD8 + T% in PB: 76.94 ± 19.96% VS 58.48±25.28% VS 55.92±29.90%,in IS: 66.9±20.2% VS 48.2±11.2%VS 34.0±14.2% ;MIF + CD4 + T% in PB:76.81 ± 14.65% VS 60.09±16.03% VS 65.88± 16.64%,in IS:66.7±19.3%VS 51.5±19.2%VS 50.7±24.4%;MIF-mRNA were increased in PBMC of AECOPD (0.0303±0.03075 ) as compared with SCOPD ( 0.0140±0.01819 )and NS ( 0.0186±0.00711 );Concentrations of MIF got no significant difference in plasma among groups :128.94±30.31 VS 119.57± 17.64 VS 123.22±33.55 (pg/ml); There was a negative correlation between FEV 1 % and MIF + CD8 + T%( both PB and IS),MIF + CD4 + T% (only in PB) and MIF in plasma ,CAT score and mMRC Grade were positively correlated with percentage of MIF-expressing T cells (both CD8 + and CD4 + ) in IS. CONCLUSION :MIF may play an important role in the process of COPD especially the acute period.