Detection of mononuclear cells as the source of the increased tissue factor mRNA in the liver from lipopolysaccharide-treated rats

Tissue factor (TP) triggers the coagulation cascade reaction in vivo. Overe xpression of TF mRNA is one leading cause of disseminated intravascular coa gulation and thrombosis-related organ failure. In response to lipopolysacch aride (LPS) stimulation, various cell types can produce TF mRNA in vitro. H owever, there is currently no agreement on what types of cells in the liver overexpress TF mRNA after LPS treatment. For the first report, we found th e increased TF mRNA with reverse transcription-polymerase chain reaction (R T-PCR), and confirmed a fourfold increase (p < 0.001 vs. control, t-test) o f the TF mRNA level with RT-competitive PCR in the liver of LPS-treated (2. 0 mg/kg i.v. injection) rats. There was no significant difference in the gl yceraldehyde-3-phosphate de-hydrogenase mRNA level between LPS-treated rats and control rats. To clarify the localization and cellular source of LPS-i nduced TF mRNA, we performed in situ hybridization analysis with [S-35]-lab eled origonucleotides probes, which we originally designed. We detected int ense signals of TF mRNA in mononuclear cells but not in endothelial cells a round the hepatic vein of LPS-treated rats. In this study, we showed that t he TF mRNA level induced by LPS treatment, which may indicate mononuclear c ells associated, significantly increased in the liver of rats. These result s will provide circumstantial support for the therapeutic strategy that mon onuclear cell should be one of the target cells to be treated in the early phase of disseminated intravascular coagulation in the liver, and that the need to suppress its overexpression of TF mRNA is essential for preventing hypercoagulable condition. (C) 2000 Elsevier Science Ltd. All rights reserv ed.