In vivo MR imaging of magnetically labeled mesenchymal stem cells in a rat model of renal ischemia.
OBJECTIVE
This study was designed to evaluate in vivo MR imaging for the depiction of intraarterially injected superparamagnetic iron oxide (SPIO)-labeled mesenchymal stem cells (MSCs) in an experimental rat model of renal ischemia.


METHODS
Left renal ischemia was induced in 12 male Sprague-Dawley rats by use of the catheter lodging method. In vivo MR signal intensity variations depicted on T2*-weighted sequences were evaluated in both the left and right kidneys prior to injection (n = 2), two hours (n = 4), 15 hours (n = 2), 30 hours (n = 2) and 72 hours (n = 2) after injection of SPIO-labeled MSCs in both kidneys. Signal intensity variations were correlated with the number of Prussian blue stain-positive cells as visualized in histological specimens.


RESULTS
In an in vivo study, it was determined that there was a significant difference in signal intensity variation for both the left and right cortex (40.8 +/- 4.12 and 26.4 +/- 7.92, respectively) and for both the left and right medulla (23.2 +/- 3.32 and 15.2 +/- 3.31, respectively) until two hours after injection (p < 0.05). In addition, signal intensity variation in the left renal cortex was well correlated with the number of Prussian blue stain-positive cells per high power field (r = 0.98, p < 0.05).


CONCLUSIONS
Intraarterial injected SPIO-labeled MSCs in an experimental rat model of renal ischemia can be detected with the use of in vivo MR imaging immediately after injection.
Department of Radiology, Konkuk University Medical Center, Research Institute of Medical Science, Konkuk University School of Medicine, Gwangjin-Gu, Seoul, Korea.
Sung Il
SI
Jung
Seung Hyup
SH
Kim
Hyo-Cheol
HC
Kim
Kyu Ri
KR
Son
Se Young
SY
Chung
Woo Kyung
WK
Moon
Hoe Suk
HS
Kim
Jong-Sun
JS
Choi
Min Hoan
MH
Moon
Chang-Kyu
CK
Sung
D000818:Animals; D004195:Disease Models, Animal; D007511:Ischemia / Q000175:diagnosis* / Q000628:therapy*; D007668:Kidney / Q000098:blood supply / Q000473:pathology; D007674:Kidney Diseases / Q000628:therapy*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D059630:Mesenchymal Stem Cells / Q000473:pathology*; D051381:Rats; D017207:Rats, Sprague-Dawley