Tracking of CM-DiI⁺/MPIO⁺ human ATMSCs and BMMSCs on two-dimensional magnetic resonance imaging (MRI).

<p>CM-DiI⁺/MPIO⁺ human ATMSCs and BMMSCs could be detected after stem cell transplantation on high resolution 4.7 Tesla MRI. Exemplary image series of an animal that had received an intra-myocardial injection of CM-DiI⁺/MPIO⁺ human ATMSCs the labeled cell clusters were clearly visible as areas of strong focal signal loss in the anterior-lateral and septal ventricular wall corresponding to the injection sites (<b>A and B</b>; <i>white arrows; axial and sagittal view</i>; <b>and </b><b>G</b>; <i>black arrow</i>; <i>showing a non-injected myocardium as respective negative control</i>). Next, an exemplary image series of an animal that underwent intra-peritoneal injection of CM-DiI⁺/MPIO⁺ human BMMSCs displayed the distribution within the entire intra-peritoneal cavity (<b>C–E</b>; <i>white arrow heads</i>; <b>and H</b>; <i>black arrows</i>; <i>showing a non-injected intra-peritoneal cavity as respective negative control</i>) involving the liver (<b>C</b>; <i>white arrow heads; axial and view</i>), the kidneys, the Gerota's fascia (<b>D</b>; <i>white arrow heads; axial view</i>), diffuse cell clusters in the surrounding intra-peritoneal areas (<b>D</b>; <i>white arrow heads; axial view</i>) as well as between the intestines (<b>E</b>; <i>white arrow heads; sagittal view</i>). Comparing the dilution series (<b>F</b>) of MPIO labeled mesenchymal stem cells to the morphological images, the amount of cells in the myocardium could be estimated to approximately 1×10⁵–5×10⁵ cells and the cells found in the liver to 5×10⁵ cells and around the kidneys to 5×10⁵–1×10⁶ cells (<b>A–D and F</b>). <i>(Cell Dilution: 1×10⁶</i><i>[1]</i>, <i>5×10⁵</i><i>[2]</i>, <i>1×10⁵</i><i>[3]</i>, <i>5×10⁴</i><i>[4]</i>, <i>2×10⁴</i><i>[5]</i><i>. Scale Bar: 2.5 cm</i>.