SearchPublisher and Institutes
You are here: Home :: Area NEM :: Medical science :: Human medicine
Kai Zacharowski, Christoph Sucker, Paula Zacharowski, Matthias Hartmann
Thrombelastography for the monitoring of lipopolysaccharide induced activation of coagulation
Keywords: Human whole blood, lipopolysaccharide, thrombelastography
During Gram-negative sepsis, lipopolysaccharide (LPS) activates toll-like receptor (TLR) 4 and induces complex responses of immune system and haemostasis. In the present study we investigated whether thrombelastography is suitable to monitor the LPS-induced activation of coagulation. Whole blood samples from healthy volunteers were incubated with LPS for various incubation periods (05 hrs), thereafter rotation thrombelastography was performed. Incubation of whole blood (3 h) with LPS markedly reduced clotting time; after 5 hrs the variable was reduced from 459 39 sec to 80 20 sec while the other thrombelastography variables (angle , clot formation time, maximal clot formation) remained unaltered. EC50 of the LPS effect on whole blood clotting time was 18 g/ml. In isolated leukocytes, diluted in platelet poor plasma, far lower LPS-concentrations were effective: 10 ng/ml LPS reduced clotting time from 439 68 sec to 200 56 sec. Experiments with the protein synthesis inhibitor cycloheximide and active site-inhibited factor VIIa revealed that LPS exerts its effects via the synthesis of tissue factor. Addition of tissue factor to whole blood samples revealed that a concentration of 100 fmol/l can be detected using thrombelastography. In whole blood samples the tissue factor concentration induced by LPS amounted up to 12 pmol/l. In summary, thrombelastography proved to be a sensitive and reliable tool for the determination of LPS-induced tissue factor mediated activation of haemostasis in whole blood samples.
Thrombosis and Haemostasis, Schattauer
Print ISSN: 0340-6245
Volume: 95, 03/2006
Pages: 557 - 561