Monitoring transplanted human mesenchymal stem cells in rat and rabbit bladders using molecular magnetic resonance imaging.
OBJECTIVE
This study investigated whether superparamagnetic iron oxide (SPIO)-labeled human mesenchymal stem cells (hMSCs) may be monitored non-invasively by in vivo magnetic resonance (MR) imaging with conventional 1.5-T system examinations in the bladders of rats and rabbits.


METHODS
SPIO were transferred to hMSCs, using GenePORTER. After SPIO-labeled hMSCs were transplanted into the animal bladders, serial T2-weighted MR images and histological examinations were performed over a 4-week period.


RESULTS
hMSCs loaded with SPIO, compared to unlabeled cells, showed similar viability. SPIO-labeled hMSCs underwent normal chondrogenic, adipogenic, and osteogenic differentiation. For SPIO-labeled hMSCs concentrations that were greater than 1x10(5), in vitro MR images showed a decrease in signal intensity. MR signal intensity at the areas of SPIO-labeled hMSCs in rat and rabbit bladders were decreased and confined locally. After injection of SPIO-labeled hMSCs into the bladder, MR imaging demonstrated that hMSCs could be seen for at least 12 weeks post-injection. The presence of iron was confirmed with Prussian blue staining in histological sections.


CONCLUSIONS
Our findings suggest that hMSCs in animal bladders can be monitored non-invasively with conventional MR imaging.
Song
Yun Seob
YS
Department of Urology, Stem Cell Therapy Center, Soonchunhyang School of Medicine, Seoul, South Korea.
Ku
Ja Hyeon
JH
Department of Urology, Seoul Veterans Hospital, Seoul, South Korea.
D017667:Adipocytes / Q000502:physiology; D000818:Animals; D002454:Cell Differentiation / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D019902:Chondrocytes / Q000502:physiology; D005290:Ferric Compounds; D006801:Humans; D008279:Magnetic Resonance Imaging; D045164:Mesenchymal Stem Cell Transplantation; D053758:Nanoparticles; D010011:Osteocytes / Q000502:physiology; D011817:Rabbits; D051381:Rats; D001743:Urinary Bladder / Q000166:cytology* / Q000502:physiology*
D005290:Ferric Compounds; C000499:ferric oxide