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09:03
Modified In Vivo Matrix Gel Plug Assay for Angiogenesis Studies
Published on: June 30, 2023
Integrin signaling is critical for pathological angiogenesis.
Ganapati H Mahabeleshwar1, Weiyi Feng, David R Phillips
1Department of Molecular Cardiology, Joseph J. Jacobs Center for Thrombosis and Vascular Biology, NB50, The Cleveland Clinic Foundation, Cleveland, OH 44195, USA.
The Journal of Experimental Medicine
|October 13, 2006
Summary
Integrin phosphorylation is vital for postnatal angiogenesis, crucial for diseases like cancer and diabetic retinopathy. Blocking beta3 integrin phosphorylation impairs blood vessel formation and endothelial cell function.
Area of Science:
- Molecular Biology
- Cell Biology
- Physiology
Background:
- Postnatal angiogenesis is critical for disease pathogenesis, including tumor growth and diabetic retinopathy.
- The precise molecular mechanisms regulating angiogenesis, particularly the role of integrin receptors, remain incompletely understood.
- Integrin phosphorylation is a key signaling event that influences cellular behavior.
Purpose of the Study:
- To investigate the role of integrin phosphorylation and signaling in the context of pathological angiogenesis.
- To elucidate the molecular interplay between integrin receptors and vascular endothelial growth factor (VEGF) signaling in endothelial cells.
Main Methods:
- Generation of knock-in mice expressing a mutant beta3 integrin unable to undergo tyrosine phosphorylation.
- Utilized two distinct models of pathological angiogenesis and an ex vivo angiogenesis assay.
- Analyzed endothelial cell adhesion, spreading, migration, and the formation of complexes between VEGF receptor-2 and beta3 integrin.
Main Results:
- Neovascularization was significantly impaired in mutant beta3 integrin knock-in mice.
- Mutant endothelial cells exhibited defective adhesion, spreading, and migration, failing to form complete capillaries.
- VEGF-induced complex formation between VEGF receptor-2 and beta3 integrin, as well as VEGF receptor-2 phosphorylation, were reduced in mutant cells, leading to impaired integrin activation.
Conclusions:
- Integrin beta3 tyrosine phosphorylation is essential for normal angiogenesis.
- The integrin-VEGF axis, mediated by beta3 integrin phosphorylation, is a critical regulator of pathological angiogenesis.
- Findings provide new mechanistic insights into targeting the integrin-VEGF pathway for therapeutic interventions in angiogenesis-related diseases.
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