Molecular imaging of α_vβ₃ integrin expression in atherosclerotic plaques with a mimetic of RGD peptide grafted to Gd-DTPA†

摘要

Aims The integrin α_vβ₃ is highly expressed in atherosclerotic plaques by medial and intimal smooth muscle cells and by endothelial cells of angiogenic microvessels. In this study, we have assessed non-invasive molecular magnetic resonance imaging (MRI) of plaque-associated α_vβ₃ integrin expression on transgenic ApoE−/− mice with a low molecular weight peptidomimetic of Arg-Gly-Asp (mimRGD) grafted to gadolinium diethylenetriaminepentaacetate (Gd-DTPA-g-mimRGD). The analogous compound Eu-DTPA-g-mimRGD was employed for an in vivo competition experiment and to confirm the molecular targeting. The specific interaction of mimRGD conjugated to Gd-DTPA or to 99mTc-DTPA with α_vβ₃ integrin was furthermore confirmed on Jurkat T lymphocytes.