Clinically Applicable 7-Tesla Magnetic Resonance Visualization of Transplanted Human Adult Stem Cells Labeled with CliniMACS® Nanoparticles

Abstract

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 × 10⁶ 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 (T₁-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.

Key words

Cardiovascular surgery - myocardial infarction - heart disease - cell transplantation - bio-imaging

References

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1 * Arjang Ruhparwar, Alireza Ghodsizad and Michael Niehaus contributed equally to this paper. This paper is to be presented at the annual meeting of The German Society for Thoracic and Cardiovascular Surgery 2006 in Hamburg as a permanent poster.