Thromb Haemost 2000; 84(05): 904-911
DOI: 10.1055/s-0037-1614135
Review Article
Schattauer GmbH

In situ Analysis of Tissue Factor-Dependent Thrombin Generation in Human Atherosclerotic Vessels

Andrew D. Westmuckett
1   From the Vascular Biology Laboratory, Thrombosis Research Institute, Emmanuel Kaye Building, Chelsea, London, UK
,
Cristina Lupu
1   From the Vascular Biology Laboratory, Thrombosis Research Institute, Emmanuel Kaye Building, Chelsea, London, UK
,
David A. Goulding
1   From the Vascular Biology Laboratory, Thrombosis Research Institute, Emmanuel Kaye Building, Chelsea, London, UK
,
Saroj Das
1   From the Vascular Biology Laboratory, Thrombosis Research Institute, Emmanuel Kaye Building, Chelsea, London, UK
,
Vijay V. Kakkar
1   From the Vascular Biology Laboratory, Thrombosis Research Institute, Emmanuel Kaye Building, Chelsea, London, UK
,
Florea Lupu
1   From the Vascular Biology Laboratory, Thrombosis Research Institute, Emmanuel Kaye Building, Chelsea, London, UK
› Author Affiliations

This work was supported by stipends from the British Heart Foundation (grants PG/95927 and PG/97045, CL), Leopold Muller Estate Trust (FL), Stanley Thomas Johnson Foundation (FL), The Royal Society (FL and CL), and the Thrombosis Research Trust. We thank Dr. David O’Reagan for providing us some of the human vascular tissue segments used in this study and to Prof. Nicholas Severs for the critical reading of the manuscript.
Further Information

Publication History

Received 24 January 2000

Accepted after resubmission 30 May 2000

Publication Date:
13 December 2017 (online)

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Summary

Tissue factor (TF) is expressed in human atherosclerotic plaques where it may contribute to the thrombogenicity of the lesions and their progression toward unstable syndromes and acute myocardial infarction. In this study we tested the hypothesis that thrombin generation takes place in the lesion. Localisation of TF, factor VII (FVII), factor X/Xa (FX/Xa), thrombin, thrombin receptor PAR-1 and FXa receptor EPR-1 was done by immunostaining, ligand binding, or immunogold electron microscopy. Quantitation of TF antigen was done using a modified ELISA on fixed tissue sections. The amount of antigen was correlated with the pattern and intensity of immunostaining as detected on consecutive sections using confocal microscopy. TFdependent generation of FXa on cryosections was used to assess the functional activity of TF. Active thrombin was detected using hirudin as a specific probe, followed by anti-hirudin IgG. Our light microscopy and immunogold electron microscopy results showed that the factors involved in TF-dependent coagulation are localised in atherosclerotic plaques in close proximity and colocalise with active thrombin and fibrin deposits. We have detected 3 to 7-fold increase of TF antigen and TF-dependent FXa generation in atherosclerotic vessels as compared with controls. Hirudin binding proved that active thrombin is present within the lesions. In conclusion, our data show that active coagulation factors are generated within atherosclerotic lesions and co-localise with their cellular receptors. These findings may suggest possible roles of the TF-dependent coagulation pathway in the intramural fibrin deposition and the progression of the atherosclerotic lesions.