Patent ID: 7767458
Filing Date: 2010-08-03
Classification: C12Q,G01N

Abstract:
1. A method of assaying a sample of whole blood or blood plasma from a patient to determine the patient's ability to generate thrombin or Factor Xa as blood-clotting factors, wherein the whole blood or blood plasma contains circulating microparticles of platelets, endothelial cells, monocytes or smooth muscle cells, which comprises the steps of: (a) contacting the whole blood or blood plasma sample with a complex comprising phospholipid micelles which contain tissue factor in a concentration of 0 to 1000 ρm to activate the circulating microparticles in the whole blood or blood plasma sample to produce thrombin or Factor Xa, and in the case where the sample is a whole blood sample, adding to the whole blood sample, a protease inhibitor to prevent protease activation in the sample; (b) following step (a) at a given point in time determining the amount of thrombin or Factor Xa generated by the circulating microparticles, present in the whole blood or blood plasma sample; (c) following step (b), at a later given point in time, again determining the amount of thrombin or Factor Xa generated by the circulating microparticles, present in the whole blood or blood plasma sample, according to steps (a) and (b); and (d) comparing the difference in the amount of thrombin or Factor Xa generated by the circulating microparticles, present in the whole blood or blood plasma sample, determined according to step (b) and according to step (c), and relating that difference against a standard calibration curve for a whole blood or blood plasma sample analyzed over the same points in time according to steps (a), (b) and (c), to determine the level of thrombin or Factor Xa produced by the circulating microparticles in the whole blood or blood plasma sample, and based upon the determined level of thrombin or Factor Xa produced by the circulating microparticles in the whole blood or blood plasma sample, determining directly the quantity of the circulating microparticles in the whole blood or blood plasma sample and based upon the quantity of the circulating microparticles in the whole blood or blood plasma sample determining the ability of the patient to generate thrombin or Factor Xa as blood clotting factors.