Methods and assays for factor viii activity
AssigneesPresident and Fellows of Harvard College, U.S. Government as represented by the Department of Veterans Affairs
InventorsGary Eugene Gilbert, Jialan Shi, Valerie A. Novakovic
Life of this patent
Estimating the term…
Abstract
The methods and compositions described herein relate to the measurement of factor VIII (fVIII) levels and/or activity.
Claims23
A method of measuring Factor VIII (fVIII) activity, the method comprising contacting a sample in which fVIII is to be measured with fibrin or fibrinogen (fibrin(ogen)) and a platelet membrane-comprising composition, under conditions that permit binding of fibrin(ogen) to said platelet membrane-comprising composition and permit binding of fVIII in said sample to said fibrin(ogen), and detecting activity of said fVIII.
A method of measuring partitioning of fVIII between fibrinogen and von Willebrand factor (vWf), the method comprising:
- contacting blood or plasma in which partitioning is to be measured with a solid support having vWf immobilized thereupon under conditions that permit binding of vWf to fVIII;
- separately measuring fVIII activity bound to said solid support via vWF and fVIII activity remaining in suspension after said blood or plasma is contacted with said support, thereby determining the proportion of fVIII bound to vWF;
- contacting blood or plasma from the same source with a solid support having fibrin(ogen) immobilized thereupon under conditions that permit binding of fibrin(ogen) to fVIII;
- separately measuring fVIII activity bound to said solid support via fibrin(ogen) and fVIII activity remaining in suspension after said blood or plasma is contacted with said support, thereby determining the proportion of fVIII bound to fibrin(ogen);
- whereby the partitioning of fVIII between vWf and fibrin(ogen) is measured.
-16. (canceled)
A method of measuring the partitioning of fVIII between binding to von Willebrand factor and binding to fibrin(ogen) in a liquid sample, the method comprising contacting a solid support comprising fibrinogen or fibrin with said sample, removing said liquid sample from said solid support, and measuring fVIII activity bound to said support versus fVIII activity remaining in said liquid sample, wherein fVIII bound to said support partitions with fibrin(ogen) and fVIII remaining in solution is free or partitions with von Willebrand factor.
-30. (canceled)
A kit for measuring fVIII activity, the kit comprising:
- fibrin(ogen);
- a platelet membrane-comprising composition;
- Factor IXa;
- Factor X;
- and
- packaging materials therefor.
-36. (canceled)
Dependencies are inferred from the claim text.