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Updated: Jun 25, 2026
07:48
Preparing a 68Ga-labeled Arginine Glycine Aspartate (RGD)-peptide for Angiogenesis
Published on: January 7, 2019
Clustering and internalization of integrin alphavbeta3 with a tetrameric RGD-synthetic peptide
Lucie Sancey1, Sancey Lucie, Elisabeth Garanger
1INSERM CRI U823, Cibles diagnostiques ou thérapeutiques et vectorisation de drogues dans les cellules tumorales, Institut Albert Bonniot, Grenoble Cedex 9, France.
Summary
This study introduces RAFT-RGD, a multimeric peptide targeting alpha(v)beta(3) integrins. RAFT-RGD shows higher affinity and promotes integrin internalization, supporting its use in cancer imaging and therapy.
Area of Science:
- Molecular Biology
- Biochemistry
- Nanotechnology
Background:
- Integrin alpha(v)beta(3) is overexpressed in tumor cells and neoendothelial cells.
- Targeting alpha(v)beta(3) is a promising strategy for cancer therapy and imaging.
Purpose of the Study:
- To develop and characterize a novel multimeric peptide scaffold, RAFT-RGD, for targeting alpha(v)beta(3) integrins.
- To investigate the binding affinity, cellular effects, and internalization mechanisms of RAFT-RGD compared to monomeric cRGD.
Main Methods:
- Fluorescence Correlation Spectroscopy (FCS) to determine binding affinity (K(D)).
- Fluorescence Recovery After Photobleaching (FRAP) to assess integrin mobility.
- Electron microscopy to visualize molecular complex formation.
- Enzyme-linked immunosorbent assay (ELISA) to quantify receptor internalization.
Main Results:
- RAFT-RGD demonstrated significantly higher affinity (lower K(D)) for alpha(v)beta(3) integrins than monomeric cRGD.
- RAFT-RGD inhibited integrin lateral mobility and induced integrin clustering.
- RAFT-RGD significantly enhanced alpha(v)beta(3) internalization via clathrin-coated vesicles.
Conclusions:
- Multimeric presentation of RGD motifs enhances binding affinity and promotes integrin-mediated internalization.
- RAFT-RGD is a potent alpha(v)beta(3) targeting agent with potential applications in cancer diagnostics and therapeutics.
- This study provides the first formal link between multimeric RGD presentation, increased affinity, and integrin cointernalization.
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