Abstract

Molecular imaging (MI) is revolutionizing biology and medicine. Yet, for the full potential of MI to be realized, new, improved chemistries and targets are required. One such target is the peripheral benzodiazepine receptor (PBR). PBR is an 18kD trans-mitochondrial membrane protein involved in steroidogenesis and other mitochondrial function^1,2. Furthermore, PBR has an expression profile making it a viable molecular target for the study of mitochondrial function and its relationship to cancer cell proliferation^3,4. Capitalizing on these observations and the availability structural identity of PBR ligand, our group has synthesized a variety of PBR targeted imaging agents (visible fluorescence, NIR, MRI) based on a conjugable form of PK11195 (a PBR ligand)⁵. These ligands have been used for both in- vitro and in-vivo PBR targeted molecular imaging. It will be shown that these agents can be visualized in a variety of PBR over-expressing cell lines and that the quantification of uptake provides physiologically relevant information. Targeted in-vivo imaging results will also be presented showing that our PBR ligands may be useful for early disease detection and surgical resection guidance.

© 2004 Optical Society of America