Interaction between tissue factor pathway inhibitor and factor V levels on the risk of venous thrombosis

Abstract

To cite this article: Dahm AEA, Bezemer ID, Sandset PM, Rosendaal FR. Interaction between tissue factor pathway inhibitor and factor V levels on the risk of venous thrombosis. J Thromb Haemost 2010; 8: 1130-2.Tissue factor pathway inhibitor 1 (TFPI) inhibits blood coagulation by forming a quaternary complex with activated coagulation factor X (FXa), activated factor (F) VII and tissue factor [1]. In plasma, 80% of TFPI is truncated and bound to lipoproteins, whereas 20% is free full-length TFPI [2]. Low levels of both truncated and full-length TFPI are weak risk factors for venous thrombosis (VT) [3]. Inherited deficiencies of TFPI have not been reported.Factor V (FV) is an important, rate-limiting coagulation factor. Together with FXa, Ca 2+ and phospholipids, activated FV forms the prothrombinase complex, which converts prothrombin to thrombin. High or low plasma levels of FV appear not to influence the risk of VT [4]. Familial deficiencies of FV are rare and follow an autosomal recessive trait. Individuals with homozygous FV-deficiency have a hemophilic phenotype, but bleeding symptoms vary between patients and there is no clear relationship between FV levels and symptoms [5].Recently, Duckers et al.[6] demonstrated a relationship between FV and TFPI. They showed that subjects deficient in FV had low levels of TFPI, which, when adjusted for FV levels, resulted in an activated protein C (APC) resistance that possibly protected against bleeding. They found that levels of FV and TFPI in healthy and FV-deficient subjects were associated, and that male patients deficient in FVIII had lower TFPI levels than healthy male controls.We have previously reported on the association between TFPI and FV in a study of low TFPI as a risk factor for VT [3]. At that time, there were no reports suggesting a relationship between TFPI and FV, and we interpreted FV as a weak determinant of TFPI levels, in line with the other coagulation factors studied. Consequently, FV levels were not considered when we estimated the TFPI-related risk for VT. As Duckers et al.[6] now have suggested a relationship between FV and TFPI, we wanted to study this association more thoroughly, as well as the relation between TFPI and other coagulation factors, including FVIII. Furthermore, we investigated the potential interaction between FV and TFPI levels related to the risk of thrombosis, in analogy to the influence on the risk for bleeding suggested by Duckers et al.[6].We analyzed data from The Leiden Thrombophilia Study, which is a case-control study of 474 cases with VT and 474 healthy controls [7]. For the current report, data from 425 controls (171 male) were available to study the association between TFPI levels and other coagulation factors. For the calculations of the risk of VT, oral contraceptive users at the time of blood sampling were excluded [3], leaving 426 cases and 397 controls. The study protocol was approved by the Leiden University Medical Center Ethics Committee. All participants gave written informed consent according to the Decl...

Correlates of plasma and platelet tissue factor pathway inhibitor, factor V, and Protein S

“…The plasma TFPIα concentration has been reported to correlate with the plasma concentration of fV 16 and of PS. 15 A correlation between plasma TFPIα and fV was present in the current study (r 2 = .18), but was weaker than that reported by Dahm and co-workers (r 2 = .39) 35 or Duckers and co-workers (r 2 = .739). 16 The differences between the latter and the current study may be at- Females have significantly lower plasma total TFPI, TFPIα, and PS than males.…”

Tissue factor pathway inhibitor: structure-function

“…Plasma concentrations of “free” and full-length TFPIα are reduced in the plasmas of patients with factor V deficiency, protein S deficiency, and perhaps factor VIII deficiency (76–79). Apparent binding interactions between full-length TFPIα and factor V and protein S have been demonstrated in plasma and by surface plasmon resonance in purified systems (76, 77, 80, 81).…”

Platelet‐Derived Factor V Is a Critical Mediator of Arterial Thrombosis

“…Platelet‐derived FVa is more resistant to activated protein C cleavage and expresses significantly more FXa cofactor activity than plasma‐derived FVa . A relationship has been demonstrated between FV and TFPI (tissue factor pathway inhibitor 1), and this interaction may influence the risk of venous thrombosis; however, there are no reports on the roles of FV in arterial thrombosis.…”