Optical spectroscopic imaging for cell therapy and tissue engineering.

Cell-based therapies hold great potential to treat a wide range of human diseases, yet the mechanisms responsible for cell migration and homing are not fully understood. Emerging molecular imaging technology enables in vivo tracking of transplanted cells and their therapeutic efficacy, which together will improve the clinical outcome of cell-based therapy. Particularly, optical imaging provides highly sensitive, safe (non-radioactive), cost-effective, and fast solutions for real-time cellular trafficking compared to other conventional molecular imaging modalities. This review provides a comprehensive overview of current advances in optical imaging for cell-based therapy and tissue engineering. We discuss different types of fluorescent probes and their labeling methods with a special focus on cardiovascular disease, cancer immunotherapy, and tissue regeneration. In addition, advantages and limitations of optical imaging-based cell tracking strategies along with the future perspectives to translate this imaging technique for a clinical realm are discussed.