title: Characterization of VCAM-1-binding peptide-functionalized quantum dots for molecular imaging of inflamed endothelium.
abstract: Inflammation-induced activation of endothelium constitutes one of the earliest changes during atherogenesis. New imaging techniques that allow detecting activated endothelial cells can improve the identification of persons at high cardiovascular risk in early stages. Quantum dots (QDs) have attractive optical properties such as bright fluorescence and high photostability, and have been increasingly studied and developed for bio-imaging and bio-targeting applications. We report here the development of vascular cell adhesion molecule-1 binding peptide (VCAM-1 binding peptide) functionalized QDs (VQDs) from amino QDs. It was found that the QD fluorescence signal in tumor necrosis factor [Formula: see text] (TNF-[Formula: see text]) treated endothelial cells in vitro was significantly higher when these cells were labeled with VQDs than amino QDs. The VQD labeling of TNF-[Formula: see text]-treated endothelial cells was VCAM-1 specific since pre-incubation with recombinant VCAM-1 blocked cells' uptake of VQDs. Our ex vivo and in vivo experiments showed that in the inflamed endothelium, QD fluorescence signal from VQDs was also much stronger than that of amino QDs. Moreover, we observed that the QD fluorescence peak was significantly blue-shifted after VQDs interacted with aortic endothelial cells in vivo and in vitro. A similar blue-shift was observed after VQDs were incubated with recombinant VCAM-1 in tube. We anticipate that the specific interaction between VQDs and VCAM-1 and the blue-shift of the QD fluorescence peak can be very useful for VCAM-1 detection in vivo.
authors.affiliation: Department of Molecular and Clinical Medicine/Clinical Physiology, The Sahlgrenska Academy and University Hospital, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Yun
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden.
authors.forename: Mátyás
authors.initials: M
authors.lastname: Molnár
authors.affiliation: Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Molecular and Clinical Medicine/Clinical Physiology, The Sahlgrenska Academy and University Hospital, University of Gothenburg, Gothenburg, Sweden.
authors.forename: Peter
authors.initials: P
authors.lastname: Friberg
authors.affiliation: Department of Molecular and Clinical Medicine/Clinical Physiology, The Sahlgrenska Academy and University Hospital, University of Gothenburg, Gothenburg, Sweden ; AstraZeneca R&D, Mölndal, Sweden.
authors.forename: Li-Ming
authors.initials: LM
authors.lastname: Gan
authors.affiliation: Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden.
authors.forename: Hjalmar
authors.initials: H
authors.lastname: Brismar
authors.affiliation: Science for Life Laboratory, Department of Applied Physics, Royal Institute of Technology, Stockholm, Sweden.
authors.forename: Ying
authors.initials: Y
authors.lastname: Fu
mesh_terms: D000818:Animals; D001011:Aorta / Q000378:metabolism / Q000473:pathology*; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D005453:Fluorescence; D007249:Inflammation / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D057054:Molecular Imaging; D010446:Peptide Fragments / Q000737:chemistry / Q000378:metabolism*; D045663:Quantum Dots; D019010:Vascular Cell Adhesion Molecule-1 / Q000737:chemistry / Q000378:metabolism*
chemical_list: D008070:Lipopolysaccharides; D010446:Peptide Fragments; D019010:Vascular Cell Adhesion Molecule-1