Brain Pretargeted PET; New Horizons to Image CNS Targets with Monoclonal Antibodies

Abstract

Antibodies are excellent targeting vectors for molecular imaging. Slow pharmacokinetics and low blood-brain barrier penetration hinder their widespread application for molecular imaging within CNS. Improved brain uptake can be achieved via transferrin-mediated transcytosis. Pretargeted imaging can increase imaging contrast and reduce radiation exposure to the patient. Here, we report for the first time that pretargeted imaging of CNS targets using intravenously administered target vectors is feasible. Specific binding to A{beta}-bound antibody was achieved. We believe that this proof-of-concept study will facilitate molecular imaging of currently undruggable targets with antibodies where small molecule PET tracer discovery has been challenging.