title: Monitoring transplanted human mesenchymal stem cells in rat and rabbit bladders using molecular magnetic resonance imaging.
abstract: 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.
authors.affiliation: Department of Urology, Stem Cell Therapy Center, Soonchunhyang School of Medicine, Seoul, South Korea.
authors.forename: Yun Seob
authors.initials: YS
authors.lastname: Song
authors.affiliation: Department of Urology, Seoul Veterans Hospital, Seoul, South Korea.
authors.forename: Ja Hyeon
authors.initials: JH
authors.lastname: Ku
mesh_terms: 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*
chemical_list: D005290:Ferric Compounds; C000499:ferric oxide