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03:53
Author Spotlight: High-Sensitivity Tissue Factor Activity Assay for Plasma Diagnosis
Published on: December 29, 2023
887
Tissue factor in COVID-19-associated coagulopathy.
Saravanan Subramaniam1, Hema Kothari2, Markus Bosmann3
1Pulmonary Center, Department of Medicine, Boston University School of Medicine, Boston, MA 02118, USA.
Thrombosis Research
|October 20, 2022
Summary
COVID-19-associated coagulopathy (CAC) involves blood clots due to aberrant tissue factor (TF) expression. This review explores TF
Area of Science:
- Hematology
- Infectious Diseases
- Pathophysiology
Background:
- Critically ill COVID-19 patients exhibit micro- and macro-thrombi, indicating COVID-19-associated coagulopathy (CAC).
- The precise mechanisms driving CAC remain unclear, though multiple factors contribute to a prothrombotic state.
- Aberrant tissue factor (TF) expression, initiating extrinsic coagulation, is implicated in thrombotic complications.
Approach:
- Systematic review of potential mechanisms driving TF expression and coagulation activation in SARS-CoV-2 infection.
- Discussion of cell-type-specific TF expression in COVID-19.
- Consideration of contributing factors including cytokines, antiphospholipid antibodies, extracellular vesicles, PRR pathways, and complement activation.
Key Points:
- Elevated proinflammatory cytokines (IL-1β, IL-6, TNF-α) in COVID-19 can induce TF expression on immune and non-immune cells.
- TF-dependent coagulation activation is a likely contributor to CAC.
- Thrombin may potentiate TF induction via protease-activated receptors.
Conclusions:
- TF-dependent pathways are central to the pathophysiology of COVID-19-associated coagulopathy.
- Understanding these mechanisms is crucial for developing targeted therapies to prevent thrombosis in severe COVID-19.
- Further research into cell-specific TF expression and its regulation is warranted.
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