Measurement of carboxypeptidase U (active thrombin-activatable fibrinolysis inhibitor) in plasma: Challenges overcome by a novel selective assay.
This article introduces a novel assay for the measurement of carboxypeptidase U (CPU) in plasma using the selective CPU substrate Bz-o-cyano-Phe-Arg (N-benzoyl-ortho-cyano-phenylalanyl-arginine), thereby limiting the interference of plasma carboxypeptidase N (CPN) as well as the intrinsic activity of procarboxypeptidase U (proCPU). A limit of detection of 0.05 U/L (10 pM) was reached. In addition, the current assay has the advantage of being easy to perform and shows excellent linearity and variability, rendering it a useful tool in the screening of samples for the presence of CPU in several patient populations and encouraging in-depth exploration of the pathophysiological role of the proCPU/CPU system.
Heylen
Evelien
E
Laboratory of Medical Biochemistry, University of Antwerp, B-2610 Wilrijk, Belgium.
Van Goethem
Sebastiaan
S
Augustyns
Koen
K
Hendriks
Dirk
D
D001671:Biochemistry / Q000379:methods; D025901:Carboxypeptidase B2 / Q000097:blood* / Q000378:metabolism; D004151:Dipeptides / Q000378:metabolism; D006801:Humans; D057230:Limit of Detection; D016014:Linear Models; D020521:Stroke / Q000188:drug therapy; D015912:Thrombolytic Therapy; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use
D004151:Dipeptides; C048251:phenylalanylarginine; D025901:Carboxypeptidase B2; D010959:Tissue Plasminogen Activator