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Updated: Jun 19, 2026
10:10
Platelet Adhesion and Aggregation Under Flow using Microfluidic Flow Cells
Published on: October 27, 2009
Ligands "activate" integrin alpha IIb beta 3 (platelet GPIIb-IIIa)
X P Du1, E F Plow, A L Frelinger
1Committee on Vascular Biology, Research Institute of Scripps Clinic, La Jolla, California 92037.
Cell
|May 3, 1991
Summary
Short RGD peptides activate integrin alpha IIb beta 3 (platelet GPIIb-IIIa), promoting fibrinogen binding and platelet aggregation. This RGD sequence acts as a trigger for high-affinity ligand interactions.
Area of Science:
- Biochemistry
- Molecular Biology
- Hematology
Background:
- Integrin alpha IIb beta 3 (platelet GPIIb-IIIa) is crucial for platelet aggregation.
- Fibrinogen binding to this integrin typically requires platelet activation by agonists.
Purpose of the Study:
- To investigate the effect of short Arg-Gly-Asp (RGD) peptides on alpha IIb beta 3 function.
- To determine if RGD peptide binding can induce high-affinity fibrinogen binding and platelet aggregation.
Main Methods:
- Studied the binding of RGD peptides to integrin alpha IIb beta 3.
- Assessed changes in integrin conformation and function.
- Evaluated the impact on fibrinogen binding and platelet aggregation.
Main Results:
- RGD peptide binding induces conformational changes in alpha IIb beta 3.
- These changes lead to the acquisition of high-affinity fibrinogen-binding function.
- RGD peptide binding triggers subsequent platelet aggregation.
Conclusions:
- The RGD sequence acts as a trigger for high-affinity ligand binding to alpha IIb beta 3.
- Structural specificities for RGD peptide-induced activation and ligand inhibition are similar.
- Certain RGD-mimetics function as both partial agonists and competitive antagonists of integrin function.
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