Fig. 2. (A) Schematic view of in vivo MRI according to the concentration of SPION-labeled hMSCs on the back muscle of rats (105 SPION-hMSCs, 5×105 SPION-hMSCs, 106 SPION-hMSCs, 104 SPION-hMSCs, 5×104 SPION-hMSCs, 106 hMSCs/mL). MRI showed a clear hypointense signal at all concentrations greater than 1×105 SPION-hMSCs/mL. (B) In vivo MR image according to the duration SPION-labeled human MSCs on the back muscle of rats. MRI showed a clear hypointense signal until 48 days after transplantation. MRI, magnetic resonance imaging; SPION, superparamagnetic iron oxide nanoparticles; hMSCs, human mesenchymal stem cells.
