Biomedical Imaging Research Center, University of Fukui, Japan
To evaluate potential application of our newly designed adenoviral PET ligand-reporter gene system in different species utilizing [18F]16á-fluoroestradiol (FES) and human estrogen receptor á ligand binding domain (hERL) [1].
An in vitro FES binding assay was performed on adenoviral infected Cos-7 cells. An in vitro expression assay was performed in single cell lineage of diverse species, using lung fibroblast cell lines of mouse, rat, guinea pig, rabbit and human to evaluate species-based differential expression. In vivo studies were performed by injecting the test and control viruses into opposite limbs of mouse calf muscle and FES autoradiography was done on six mice.
A 57-fold higher FES uptake was observed in test adenovirus infected Cos-7 cells than in the control. The highest expression was observed in human, with moderate levels in rat, rabbit and guinea pig and minimal expression in mouse cells. In vivo, the sides injected with test adenovirus showed higher accumulation of FES than the other sides.
With the above promising results, future small animal PET imaging trials can validate our system for prospective clinical use.
[18F]16á-fluoroestradiol (FES), reporter gene, gene therapy
