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Updated: May 24, 2026

Flow Cytometry Analysis of Tissue Factor Expression in Human Platelets
Published on: November 22, 2024
Platelet tissue factor pathway inhibitor modulates intravascular coagulation
1Blood Research Institute, Blood Center of Wisconsin, Milwaukee, WI 53201-2178, USA. susan.maroney@bcw.edu
Abstract:
Tissue factor pathway inhibitor (TFPI) is produced by megakaryocytes and is found internally within quiescent platelets but is not in α-granules. It is released in soluble form and expressed on the surface of platelets that are dual activated with thrombin plus collagen. Platelet TFPI is exclusively TFPIα, the most evolutionarily conserved TFPI isoform. It appears to be physiologically active as an inhibitor of tissue factor (TF) initiated FXa generation in vitro, and acts locally to dampen clot growth in a murine vascular injury model. These data suggest that platelet TFPI plays an important role in modulating TF activity within a growing clot thereby preventing formation of an occlusive clot.
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