ABSTRACT
In order to make use of stem cells for nervous system repair, it is necessary to know the fate of stem cells and, therefore, the ability to track the stem cells after implantation in vivo is required. Nanoparticle-based imaging modalities are an extremely promising set of techniques which provide a unique set of attributes that may be useful for in vivo tracking of stem cells. The conventional method of tracking stem cells in the body is to label the stem cells in vitro with a fl uorescent label such as BrdU or to genetically modify the cells to express GFP, introduce them into the body, and take tissue sections for immunohistochemistry. The main drawback of this procedure is that it is highly invasive, requiring the removal of signifi cant amounts of tissue and, in most cases, sacrifi cing the study animal; thus making longitudinal studies more diffi cult.
