Tracking and Imaging of Transplanted Stem Cells in Animals

The shortage of organ donors has contributed to the rapid development of cell-based therapy in which stem cells are transplanted and administered to repair or regenerate damaged tissues or organs. The common sources of stem cells are embryonic, mesenchymal, stromal, and induced pluripotent cells. Despite the popularity of stem cell therapy, evaluation of the therapeutic efficiency of transplanted stem cells and their tracking in vivo remains a major challenge. Current imaging modalities such as magnetic resonance imaging, radionuclide imaging, and positron emission tomography have certain limitations such as toxicity, shorter circulation time, and higher cost. Here, we describe near-infrared imaging methods to track and monitor stem cell recruitment to the site of injury.