Abstract:

Objective To study the procoagulant property of tissue factor-positive microparticles（TF⁺MP） generated in vitro through the culture and stimulation of cell line. Methods Human acute monocytic leukemia cell line（THP-1） was stimulated by different concentrations of lipopolysaccharide（LPS）. Microparticle（MP）was separated by gradient centrifugation. Thrombin generation abilities of tissue factor（TF） and phosphatidylserine（PS） were determined by thrombin generation test by adding MP into MP-depleted plasma. ZYMUPHEN MP-TF kit was performed to determine TF procoagulant property. The 0.45 and 0.65 μm filters were selected to determine MP procoagulant properties（< 0.45 and < 0.65 μm）. Results Both thrombin generation test and chromogenic substrate test demonstrated a procoagulant property of MP generated in vitro. Thrombin generation test further showed that the procoagulant property of MP increased by the addition of LPS in a concentration-dependent manner. MP > 0.65 μm had a strong procoagulant property. Conclusions MP generated in vitro through the culture and stimulation of THP-1 demonstrates certain procoagulant property.

Key words: Tissue factor-positive microparticles, Tissue factor, Phosphatidylserine, Thrombin generation test