Immunological Assay for the Determination of Procarboxypeptidase U Antigen Levels in Human Plasma

Mats Stromqvist; Katinka Schatteman; Judith Leurs; Robert Verkerk; Jan-Olof Andersson; Thord Johansson; Simon Scharpe; Dirk Hendriks

doi:10.1055/s-0037-1612656

Thrombosis and Haemostasis, Inhaltsverzeichnis

Thromb Haemost 2001; 85(01): 12-17
DOI: 10.1055/s-0037-1612656

Rapid Communications

Schattauer GmbH

Immunological Assay for the Determination of Procarboxypeptidase U Antigen Levels in Human Plasma

Mats Stromqvist

²Department of Molecular Biology, AstraZeneca R&D, Molndal, Sweden

,

Katinka Schatteman

¹Department of Medical Biochemistry, University of Antwerp, Antwerp, Belgium

,

Judith Leurs

¹Department of Medical Biochemistry, University of Antwerp, Antwerp, Belgium

,

Robert Verkerk

¹Department of Medical Biochemistry, University of Antwerp, Antwerp, Belgium

,

Jan-Olof Andersson

²Department of Molecular Biology, AstraZeneca R&D, Molndal, Sweden

,

Thord Johansson

²Department of Molecular Biology, AstraZeneca R&D, Molndal, Sweden

,

Simon Scharpe

¹Department of Medical Biochemistry, University of Antwerp, Antwerp, Belgium

,

Dirk Hendriks

¹Department of Medical Biochemistry, University of Antwerp, Antwerp, Belgium

› Institutsangaben

Abstract

Summary

The importance of carboxypeptidase U as a novel regulator of the fibrinolytic rate has attracted a lot of interest recently. In the present work, an ELISA was developed using polyclonal antibodies raised against recombinant proCPU, expressed in DON cells. The assay determines the antigen concentration of the zymogen of carboxypeptidase U, procarboxypeptidase U, in human citrated plasma or EDTA plasma. No interference is observed with plasma carboxypeptidase N. The assay is very reproducible (within-run: 4.6% CV, between-run: 6.8% CV). In a group of 479 healthy individuals the mean proCPU antigen concentration is 13.4 μg/ml (SD 2.5 μg/ml). A good correlation is found with the functional procarboxypeptidase U assay described earlier (r = 0.82, p <0.0001) (Schatteman K, Goossens F, Scharpé S, Neels H, Hendriks D Clin Chem 1999; 45: 807-813). The significant correlation between the proCPU antigen concentration and the 50% clot lysis time stresses its importance as a player in fibrinolysis control.

Abbreviations: CPU, carboxypeptidase U; proCPU, procarboxypeptidase U; TAFI, thrombin activatable fibrinolysis inhibitor; AP, alkaline phosphatase; EDTA, ethylenediamine tetra-acetic acid; Tris, tris-(hydroxyethyl)-aminomethane; PPACK, phenylalanyl-prolyl-chloromethyl ketone; SP, sulphopropyl; HEPES, N-2-hydroxyethylpiperazine-N’-ethanesulfonic acid

Keywords

Fibrinolysis - carboxypeptidase U - TAFI - assay - ELISA

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Referenzen

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