Fig. 2

Schematic of reporter gene labeling for intrahepatic stem cell tracing. The reporter genes are transferred into the genome of target stem cells via transfection, transduction with viral vectors, or acquisition from GM animals. Activated by promoters, reporter genes encode various reporter proteins, such as fluorophores (e.g., GFP), enzymes (e.g., luciferase), transporter proteins (e.g., NIS), and so forth. Generated signals are captured by different imaging devices; for example, optical charge-coupled device, SPECT, or PET. GM genetically modified, GFP green fluorescent protein, NIS sodium iodide symporter