Simple Methods for Tracking Stem Cells with Cu-64-Labeled DOTA-hexadecyl-benzoate

Abstract

The purpose of this study was to evaluate Cu-64-labeled hexadecyl-1,4,7,10-tetraazacyclododecane-tetraacetic acid-benzoate (Cu-64-DOTA-HB) (1) as positron emission tomography (PET) radiotracer for stem cell imaging. Hexadecyl-DOTA-benzoate (DOTA-HB) (2) was efficiently labeled with Cu-64 (>99%), and cell labeling efficiency with adipose-derived stem cells (ADSCs) was over 50%. Labeling with 1 did not compromise cell viability. In the PET imaging, intramuscularly transplanted 1-labeled ADSCs were monitored for 18 h in normal rat heart. These results indicate that 1 can be utilized as a promising radiotracer for monitoring of transplanted stem cells.