A functional CATTn microsatellite in the promoter of macrophage migration inhibitory factor in sepsis

Abstract

Objective MIF, a potent pro -inflanmkatory cytokine, plays a pivatol role in the pathogenesis of sepsis. A novel CATT microsatellite at position -794 of the human MIF gene functionally ＇affects the activity of the MIF promoter and correlates with the disease severity in rheumatoid arthritis, ulcerative colitis, atopy or sarcoidosis. The purpose of this study is to determine whether MIF microsatellite is associated with the susceptibility to and outcome of severe sepsis. Methods After approval by the hospital and national ethics committee, written informed consent was obtained from the patient or a first degree relative. Blood samples were obtained from 98 postoperative patients with severe sepsis （sepsis group） and 73 controls. Microsatellite was determined using polymerase chain reaction （PCR） with a FAM -labeled upstream primer combining capillary electrophoresis. Statistical analysis was done by Fisher＇ s exact test. P 〈 0.05 was regarded as statistically significant. Results Tbe underlying diseases for the severe sepsis patients were peritonitis, pancreatitis, pneumonia and multiple trauma. The APACH II score in sepsis was 22.5 ±2. 1, the mortality in sepsis patients reached 51%. There is no significant difference in the race, age, sexual. Four kinds of alleles with 4, 5, 6, or 7 - CATT repeat units and seven kinds of genotypes with 4/4,4/5,4/6,4/7,5/5,5/ 6,6/6 CATT repeat units were detected among these patients either with or without sepsis. The genotype distribution and allele frequencies between sepsis individuals and controls, between smvivors and non - survivors didn＇ t differ （P 〉 0.05）. Conclusion This study shows that the functional CATTn microsatellite in the promoter of macrophage migration inhibitory factor is neither related to the incidence of severe sepsis nor to the fatal outcome of sepsis. Key words: sepsis; macrophage migration inhibitory factor; microsatellite; polymorphism