Abstract
Phosphatidylserine (PS) is a well-characterized biomarker for apoptosis. Ligands that bind to PS can be used for noninvasive imaging of therapy-induced cell death, particularly apoptosis. In this study, we screened a random 12-mer peptide phage library on liposomes prepared from PS. One clone displaying the peptide SVSVGMKPSPRP (designated as PS3-10) bound to PS approximately 4-fold better than its binding to phosphatidylcholine and 18-fold better than to bovine serum albumin in a solid-phase binding assay. In addition, the binding of the corresponding PS3-10 peptide to PS was significantly higher than that of a scrambled peptide. PS3-10 phages, but not a control 4-2-2 phage, bound to aged red blood cells that had PS exposed on their surface. Binding of PS3-10 phages and PS3-10 peptide to TRAIL-induced apoptotic DLDI cells was 3.2 and 5.4 times higher than their binding to untreated viable cells, respectively. Significantly, immunohistochemical staining confirmed selective binding of PS3-10 phages to apoptotic cells. Our data suggest that panning of phage display libraries may allow the selection of suitable peptide ligands for apoptotic cells and that PS3-10 peptide may serve as a template for further development of molecular probes for in vitro and in vivo imaging of apoptosis.
Original language | English (US) |
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Pages (from-to) | 417-426 |
Number of pages | 10 |
Journal | Molecular imaging |
Volume | 6 |
Issue number | 6 |
DOIs | |
State | Published - Nov 2007 |
ASJC Scopus subject areas
- Biotechnology
- Molecular Medicine
- Biomedical Engineering
- Radiology Nuclear Medicine and imaging
- Condensed Matter Physics
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