Background: Intra-myocardial transplantation of bone marrow derived cells is currently under clinical evaluation as a therapy for heart failure. A major limitation of all clinical studies for myocardial restoration through cell transfer is the inability to track the fate of the transplanted cells. We present a clinically applicable technique using advanced ultra high-field 7-Tesla (7T) magnetic resonance imaging (MRI) of nanoparticle-labeled transplanted human EPCs in porcine ischemic hearts.
Methods: CD133 positive cells were isolated from bone marrow by magnetic bead selection. Positive cells (5 - 8 x 10 (6) cells) were transplanted into porcine ischemic myocardium (n = 8). Control animals (n = 3) received a medium injection. MRI on a 7T scanner was performed to demonstrate the distribution of the EPCs.
Results: CD133+ cells were identified on gradient echo images (T(1)-weighted) within the myocardium 4 weeks after transplantation.
Conclusions: Magnetically labeled EPCs transplanted for therapeutic neovascularization or reduction of infarct size in myocardial ischemia can be visualized by MRI at high-field strengths.