title: Measuring the mechanical properties of blood clots formed via the tissue factor pathway of coagulation.
abstract: Thrombelastography (TEG) is a method that is used to conduct global assays that monitor fibrin formation and fibrinolysis and platelet aggregation in whole blood. The purpose of this study was to use a well-characterized tissue factor (Tf) reagent and contact pathway inhibitor (corn trypsin inhibitor, CTI) to develop a reproducible thrombelastography assay. In this study, blood was collected from 5 male subjects (three times). Clot formation was initiated in whole blood with 5 pM Tf in the presence of CTI, and fibrinolysis was induced by adding tissue plasminogen activator (tPA). Changes in viscoelasticity were then monitored by TEG. In quality control assays, our Tf reagent, when used at 5 pM, induced coagulation in whole blood in 3.93 ± 0.23 min and in plasma in 5.12 ± 0.23 min (n=3). In TEG assays, tPA significantly decreased clot strength (maximum amplitude, MA) in all individuals but had no effect on clot time (R time). The intraassay variability (CVa<10%) for R time, angle, and MA suggests that these parameters reliably describe the dynamics of fibrin formation and degradation in whole blood. Our Tf reagent reproducibly induces coagulation, making it an ideal tool to quantify the processes that contribute to mechanical clot strength in whole blood.
authors.affiliation: Department of Biochemistry, University of Vermont, Burlington, Colchester, VT 05446, USA.
authors.forename: J H
authors.initials: JH
authors.lastname: Foley
authors.forename: S
authors.initials: S
authors.lastname: Butenas
authors.forename: K G
authors.initials: KG
authors.lastname: Mann
authors.forename: K E
authors.initials: KE
authors.lastname: Brummel-Ziedins
mesh_terms: D000328:Adult; D001772:Blood Cell Count; D001777:Blood Coagulation; D001780:Blood Coagulation Tests / Q000379:methods*; D001809:Blood Viscosity; D004548:Elasticity; D005337:Fibrin / Q000737:chemistry; D005342:Fibrinolysis; D006801:Humans; D008297:Male; D010940:Plant Proteins / Q000737:chemistry; D015539:Platelet Activation; D011786:Quality Control; D015203:Reproducibility of Results; D013916:Thrombelastography / Q000379:methods*; D013925:Thromboplastin / Q000737:chemistry; D013997:Time Factors
chemical_list: D010940:Plant Proteins; C052160:trypsin inhibitor, Zea mays; D005337:Fibrin; D013925:Thromboplastin