Non-toxic MRI contrast that can be monitored in vivo during cell replacement therapy.
- Based on a magnetosome associated prokaryotic gene, MagA, leading to lower toxicity than nanoparticle systems.
- MagA can be used to monitor stem cell graft non-invasively.
Cell replacement therapy and regenerative medicine has been investigated for treating incurable diseases including diabetes, autoimmune diseases, and neurodegenerative diseases. In these treatments, it is difficult to monitor the fate of grafted cells in a non-invasive manner over the lifetime of the cell graft. Magnetic resonance imaging (MRI) and other imaging methods are capable of imaging deep tissues with high spatial and temporal resolution. Current methods for providing MR contrast to grafted cells have incorporated nanoparticles; however dilution and toxicity remain a concern with these systems. Emory inventors have developed a potential MRI reporter using a genetic reporter system that allows for long-term monitoring of grafted cells. Expression of this magnetosome associated prokaryotic gene, MagA, accumulates iron, leading to T2 MRI contrast that has shown lower toxicity than currently used nanoparticle systems. Furthermore, the growth rate, live-dead count, and caspase-3 expression of cells suggest lower toxicity of MagA on mouse embryonic stem cells (mESCs) compared to current MR contrast.
Publication: AWS Chan et al., (2014). Theranostics. 4 (10): 972-989.