Chromogene Methode zur funktionellen TFPI-Bestimmung

Zusammenfassung

Aufgrund der vielfältigen TF(tissue factor)-Funktionen ist auch sein natürlicher Gegenspieler, der TFPI (tissue factor pathway inhibitor) von Interesse. Zur quantitativen TFPIBestimmung kann die Antigenkonzentration oder die TFPIAktivität gemessen werden. Methode: Es wird ein chromogener Test zur funktionellen Bestimmung des TFPI vorgestellt und für die Anwendung im Routinelabor modifiziert. Anhand der Testung von über 700 Proben aus einer Heparinstudie mit Gesunden wurde seine Praxistauglichkeit geprüft. Mit der beschriebenen Methode werden sowohl die Aktivität von freiem als auch Lipoprotein-assoziiertem TFPI erfasst. Zusammenfassung: Der chromogene Test erwies sich als einfach und schnell durchführbar und zeichnet sich durch eine hohe Reproduzierbarkeit aus. Insbesondere für die Bestimmung von TFPI in Plasmaproben nach Heparingabe bietet er aufgrund der exzellenten Korrelation eine schnellere und ökonomischere Alternative zur Bestimmung der Gesamt-TFPI-Antigenkonzentration mittels ELISA.

Summary

Due to the manifold functions of tissue factor (TF), also tissue factor pathway inhibitor (TFPI), its endogenous antagonist, is of interest. For the determination of TFPI, either its antigen concentration or its activity can be measured. Method: A chromogenic assay for the functional determination of TFPI is presented and modified for its application in the routine laboratory. Its suitability for daily use was evaluated by testing more than 7000 plasma samples from a heparin study in healthy volunteers. In addition, our data confirm that the method records the activity of both free- and lipoprotein-associated TFPI. Conclusion: The chromogenic assay proved to be rapid and easy to perform and features a high reproducibility. Due to excellent correlation of the results with the total TFPI antigen concentrations, the method represents a more rapid and economic alternative to the determination of total TFPI antigen by ELISA in plasma samples after heparin application.

Schlüsselwörter

TFPI-Aktivität - chromogene TFPI-Bestimmung - Heparin

Keywords

TFPI activity - chromogenic TFPI determination - heparin

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