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Role of tissue factor in embryonic blood vessel development
P Carmeliet1, N Mackman, L Moons
1Center for Transgene Technology and Gene Therapy, Flanders Interuniversity Institute for Biotechnology, Leuven, Belgium.
Nature
|September 5, 1996
Summary
Inactivating the tissue factor gene (TF) caused abnormal blood circulation and embryo death in mice. This suggests tissue factor is crucial for proper blood vessel development and function.
Area of Science:
- Developmental Biology
- Hematology
- Molecular Biology
Background:
- Tissue factor (TF) initiates blood coagulation and is implicated in thrombosis, inflammation, and cancer.
- TF is a member of the cytokine-receptor superfamily, acting as a receptor and cofactor for factor VII/VIIa.
- Beyond coagulation, TF influences intracellular signaling, metastasis, angiogenesis, and embryogenesis.
Purpose of the Study:
- To investigate the role of tissue factor in embryonic development and blood vessel formation.
- To determine the consequences of tissue factor gene inactivation on early embryonic vascularization.
Main Methods:
- Gene inactivation of tissue factor (TF) in mice.
- Analysis of embryonic development and vascular morphology up to embryonic day 8.5.
- Assessment of smooth muscle actin expression in vitelline vessels of TF-null embryos.
Main Results:
- Inactivation of the TF gene led to abnormal yolk sac to embryo circulation beyond embryonic day 8.5.
- TF-null embryos exhibited wasting and death, indicating critical developmental defects.
- Vitelline vessels in TF-null mice were deficient in smooth muscle alpha-actin-expressing mesenchymal cells.
Conclusions:
- Tissue factor plays an essential role in embryonic blood vessel development.
- The absence of TF disrupts the organization of the vessel wall by affecting mesenchymal cell recruitment.
- TF is vital for maintaining circulatory integrity during early embryogenesis.
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