Geralda A.F. van Tilborg1, Esad Vucic2, Gustav J. Strijkers1, David P. Cormode2, Venkatesh Mani2, Torjus Skajaa2, Chris P.M. Reutelingsperger3, Zahi A. Fayad2, Willem J.M. Mulder2, Klaas Nicolay1
1Biomedical NMR, Department of Biomedical Engineering, Eindhoven University of Technology, Eindhoven, Netherlands; 2Translational and Molecular Imaging Institute, Mount Sinai School of Medicine, New York, NY, USA; 3Cardiovascular Research Institute Maastricht, Department of Biochemistry, Maastricht University, Maastricht, Netherlands
Apoptosis and macrophage burden are believed to correlate with plaque vulnerability. In the present study, we investigated the use of a small annexin A5-functionalized bimodal micellar contrast agent for non-invasive magnetic resonance imaging (MRI) of macrophages and/or apoptotic cells in atherosclerotic lesions of apoE-/- mice. In vivo MRI of the abdominal aorta and ex vivo near-infrared fluorescence imaging of whole aortas revealed an elevated uptake of the annexin A5-micelles compared to untargeted control-micelles. Ex vivo immunofluorescence images of cryosections confirmed binding of the annexin A5-micelles to macrophages and apoptotic cells.