Switching on the Lights for Gene Therapy
Figure 3
In vivo imaging of regulated gene expression.
Multimodal imaging ([18F]FLT-, [18F]FDG- and [18F]FHBG-PET) of inducible gene expression by PET in nude mice bearing subcutaneous human Gli36ΔEGFR xenografts employing HSV-Switch-TG17 or HET6C-tk39. Mice were randomized to mifepristone- or doxycycline-treated (each group n = 7) and untreated (n-mif = 8; n-dox = 12) groups. Indicated xenografts (arrowhead) were injected with HSV-Switch-TG17 and HET6C-tk39 respectively (>2×106 t.u.) 48h prior to PET-imaging, resulting in high accumulation of [18F]FHBG in HSV-Switch-TG17 or HET6C-tk39 infected and mifepristone- or doxycycline-treated tumors as compared to some background activity in non-treated tumors.