Influence of the surface on thrombin generation

• Published in: International journal of laboratory hematology Vol. 30; no. 4; pp. 269 - 277
• Main Author: STIEF, T. W.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.08.2008
• Subjects: Blood Coagulation Tests - methods; coagulation activation; Hemolysis; Humans; plastic; polystyrol; Thrombin; Thrombin - analysis
• ISSN: 1751-5521; 1751-553X
• DOI: 10.1111/j.1751-553X.2007.00959.x

Summary Thrombin generation depends on the surface of the blood vessel or container. With a new ultra‐sensitive and ‐specific thrombin assay the surface‐dependent thrombin generation was quantified. Citrated blood or plasma was preincubated for 1 h (37 °C). Citrated blood, plasma, or plasma with 0–10 g/l hemoglobin–erythrocyte microparticles (Hb–MP) were preincubated at 23 °C or at 37 °C. Plasma samples (50 μl) were recalcified in polystyrol (PS) wells and incubated for different coagulation reaction times (CRT). Final supramolar arginine concentrations, 0.1% Triton X 100, and chromogenic thrombin substrate concentrations in the onefold km–range were added and the linear ΔA/t was measured in the recalcified coagulation activity assay (RECA). Aprotinin or corn trypsin inhibitor were added. (i) Recalcification of plasma (in different monovettes) pre‐incubated for 1 h (37 °C) generated the following thrombin activities after 7 min (37 °C): 0.74 IU/ml (polypropylene (PP)‐citrate), 0.39 IU/ml (PP‐EDTA), 0.06 IU/ml (PP‐heparin), 1.38 IU/ml (PS), 0.63 IU/ml (1 ml volume PP), 0.13 IU/ml (15 ml volume PP), and 3.62 IU/ml (glass). (ii) Recalcification of preincubated whole blood generated up to about fivefold more thrombin. (iii) Thrombin generation is proportional to the plasmatic concentration of Hb–MP, 10 g/l Hb–MP generating about 4 IU/ml thrombin within 20 min CRT. (iv) The IC50 of aprotinin and corn typsin inhibitor on thrombin generation in RECA are about 2 KIU/ml and about 1 U/ml, respectively. The reaction wall, the preincubation temperature, and hemolysis influences thrombin generation. The RECA allows to diagnose the prothrombotic capacity of any material.