Reporter gene imaging and its role in imaging-based drug development.

Reporter gene imaging (RGI) is described as the methodology that involves imaging of the encoding proteins that can be used as surrogate markers when fused with regulatory regions of the gene of interest. It provides a means to indirectly monitor molecular processes that are implicated in the pathophysiology of several diseases. The modalities utilized in RGI include MRI, PET, SPECT, as well as optical imaging modalities, such as bioluminescence and fluorescence. RGI provides a highly specific way to qualitatively and quantitatively assess cell targeting, transfection, protein expression and other intracellular processes, which are valuable for pharmacodynamic and pharmacokinetic assessment of cellular, gene and oncolytic viral therapeutics.