[In vivo magnetic resonance imaging tracking of transplanted adipose-derived stem cells labeled with superparamagnetic iron oxide in rat hearts].
OBJECTIVE
To investigate the feasibility of in vivo magnetic resonance imaging (MRI) tracking of transplanted adipose-derived stem cells (ADSCs) labeled with superparamagnetic iron oxide (SPIO) in rat heart.


METHODS
ADSCs were labeled with poly-L-lysine (PLL)-SPIO complexes. Intracellular iron uptake was identified by Prussian blue stain and transmission electromicroscopy. Trypan blue staining was used to test the viability of the labeled cells. In vitro MRI of labeled cells was performed. SPIO-labeled ADSCs were transplanted into normal rat hearts and were in vivo imaged with MRI. Image findings on MRI were correlated with histological findings of the rat hearts.


RESULTS
The labeling efficacy of ADSCs with PLL-SPIO was nearly 100%. Light microscopy revealed the SPIO particles were located in the cytoplasm of the ADSCs by Prussian blue staining. Transmission electromicroscopy revealed that the SPIO particles were located in the endosomes in the cytoplasm. There was no significantly deference in viability between labeled and unlabeled groups demonstrated by Trypan blue test (P > 0.05). MRI showed signal loss in gel mixed with labeled cells as compared with the unlabeled cells group and blank group. Signal void on rat hearts were demonstrated on MRI and were well correlated with histological findings where Prussian-blue-stain positive cells presented.


CONCLUSIONS
MRI can be used to in vivo track the transplanted ADSCs labeled with SPIO into rat hearts and facilitate to understand the conditions of the labeled cells in the transplanted areas.
Liu
Zai-Yi
ZY
Department of Radiology, Guangdong General Hospital, Guangzhou 510080, China.
Wang
Ying
Y
Wang
Guang-Yi
GY
Li
Xiao-Hong
XH
Li
Yan
Y
Liang
Chang-Hong
CH
D017667:Adipocytes / Q000166:cytology*; D000818:Animals; D002454:Cell Differentiation; D003287:Contrast Media / Q000008:administration & dosage; D003911:Dextrans / Q000008:administration & dosage; D005240:Feasibility Studies; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000008:administration & dosage; D008297:Male; D009206:Myocardium / Q000166:cytology* / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D033581:Stem Cell Transplantation / Q000379:methods*; D013234:Stem Cells / Q000166:cytology
D003287:Contrast Media; D003911:Dextrans; D058185:Magnetite Nanoparticles; C097921:ferumoxtran-10