In Vivo Imaging of Anticancer Drug Activity At the Cellular Level

Intravital fluorescence microscopy provides cellular information under physiological conditions in vivo.  We have developed a novel optical imaging modality based on fluorescence detection that enables the study of cellular response to anticancer drug treatment in tumor mouse models.  Fluorescently labeled drug can be tracked in the tumor over time and the cellular uptake in vivo can be determined at subcellular resolution.  This imaging modality provides both pharmacokinetic and pharmacodynamic information of drug effects on tumors in vivo.  Here we demonstrate the ability to image drug activity at the cellular level in vivo.  These results can be used in the future to study the cellular mechanism of both clinically successful and unsuccessful drugs as well as tumor resistance heterogeneity during drug treatment.