Assay kit and method for detecting modulators of gpib-thrombin interaction

Abstract

The present invention is in the field of coagulation diagnostics and relates to methods for detecting modulators of GPIb-thrombin interaction in a sample. To this end, the sample is contacted with isolated mutated GPIbα protein and thrombin, and the formation of a complex between mutated GPIbα protein and thrombin is determined.

What is claimed is: 
     
         1 . An assay kit for carrying out a method for detecting modulators of glycoprotein Ib (GPIb)-thrombin interaction in a sample, the assay kit containing a first reagent containing isolated GPIbα protein, the GPIbα protein being mutated and, compared to the wild-type sequence of the human GPIbα protein, containing at least the amino acid residues 1-268 and having a substitution Xaa at at least one of the positions 233, 235, 237 and 239 (SEQ ID NO: 1), and a second reagent containing thrombin. 
     
     
         2 . The assay kit of  claim 1 , wherein the second reagent comprises a solid phase to which the thrombin is associated. 
     
     
         3 . The assay kit of  claim 1 , further containing one or more reagents for detecting the isolated GPIbα protein. 
     
     
         4 . The assay kit of  claim 3 , wherein the reagent(s) for detecting the isolated GPIbα protein comprise(s) an enzyme-labeled antibody specific for the isolated GPIbα protein and a substrate for the enzyme. 
     
     
         5 . The assay kit of  claim 1 , wherein the first reagent comprises a solid phase to which the isolated GPIbα protein is associated. 
     
     
         6 . The assay kit of  claim 1 , further containing one or more reagents for detecting thrombin. 
     
     
         7 . The assay kit of  claim 6 , wherein the reagent(s) for detecting thrombin comprise(s) either an enzyme-labeled antibody specific for thrombin and a substrate for the enzyme or a peptide substrate having a thrombin-cleavable signal group.