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Updated: Aug 6, 2026
08:13
Tail Vein Transection Bleeding Model in Fully Anesthetized Hemophilia A Mice
Published on: September 30, 2021
In a nutshell: Explaining joint and muscle bleeding in individuals with haemophilia A and B
Benjamin K Lau1, Shantanu Srivatsa2, Nigel Mackman3
1Department of Biochemistry and Biophysics, UNC Chapel Hill School of Medicine, Chapel Hill, North Carolina, USA.
British Journal of Haematology
|July 17, 2026
Summary
Vascular injury triggers platelet and fibrin plug formation. Tissue factor (TF) expression levels correlate with bleeding risk, with low TF in joints and muscles increasing vulnerability in factor deficiencies.
Area of Science:
- Hematology
- Hemostasis
- Vascular Biology
Background:
- Vascular injury initiates hemostasis via von Willebrand factor (VWF) and tissue factor (TF).
- Platelet adhesion, activation, and aggregation, alongside the coagulation cascade, form a stable platelet-fibrin plug.
- TF triggers thrombin generation, which amplifies platelet activation, integrating platelet and fibrin components.
Purpose of the Study:
- To elucidate the mechanisms of platelet-fibrin plug formation.
- To investigate the correlation between tissue factor expression and bleeding phenotypes in hemophilia.
Main Methods:
- Review of hemostatic mechanisms involving VWF, TF, platelets, and coagulation factors.
- Anatomical correlation of bleeding sites with tissue-specific TF expression patterns.
Main Results:
- Hemostasis involves VWF-mediated platelet adhesion and TF-triggered coagulation, forming a combined platelet-fibrin plug.
- High TF expression in vital organs offers protection, while low TF in joints and muscles increases bleeding risk in factor deficiencies (e.g., hemophilia A and B).
Conclusions:
- The interplay between platelet aggregation and fibrin mesh formation is crucial for stable hemostasis.
- Tissue factor distribution significantly influences the susceptibility to bleeding in factor-deficient states, particularly in joints and muscles.
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01:24Disorders of Hemostasis
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Thromboembolic Disorders
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Thromboembolic Disorders
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01:05Introduction to Hemostasis
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01:22Formation of the Platelet Plug
The platelet phase, the second stage of hemostasis, commences around 15-20 seconds after an injury. It follows and overlaps with the vascular phase, during which blood vessels constrict to minimize blood loss.
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01:16Vascular Spasm
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