title: Magnetically labeled mesenchymal stem cells after autologous transplantation into acutely injured liver.
abstract: OBJECTIVE
  To evaluate tracking of magnetically labeled mesenchymal stem cells (MSCs) after intraportal transplantation.
  
  
  METHODS
  Mononuclear cells were isolated from bone marrow aspirates of pigs by density gradient centrifugation, cultured and expanded, after which, they were incubated with super paramagnetic iron oxide (SPIO). Prussian blue staining was performed to highlight intracellular iron. To establish swine models of acute liver injury, 0.5 g/kg D-galactosamine was administrated to 10 pigs, six of which were injected via their portal veins with SPIO-labeled MSCs, while the remaining four were injected with unlabeled cells. Magnetic resonance imaging (MRI) was performed with a clinical 1.5T MR scanner immediately before transplantation and 6 h, 3 d, 7 d and 14 d after transplantation. Prussian blue staining was again performed with the tissue slices at the endpoint.
  
  
  RESULTS
  Prussian blue staining of SPIO-labeled MSCs had a labeling efficiency of almost 100%. Signal intensity loss in the liver by SPIO labeling on the FFE (T2*WI) sequence persisted until 14 d after transplantation. Histological analysis by Prussian blue staining confirmed homing of labeled MSCs in the liver after 14 d; primarily distributed in hepatic sinusoids and liver parenchyma.
  
  
  CONCLUSIONS
  MSCs were successfully labeled with SPIO in vitro. MRI can monitor magnetically labeled MSCs transplanted into the liver.
authors.affiliation: Department of Hepatobiliary Surgery, the Affiliated Drum Tower Hospital of Nanjing University Medical School, No. 321 Zhongshan Road, Nanjing, Jiangsu Province, China.
authors.forename: Xiao-Lei
authors.initials: XL
authors.lastname: Shi
authors.forename: Jin-Yang
authors.initials: JY
authors.lastname: Gu
authors.forename: Bing
authors.initials: B
authors.lastname: Han
authors.forename: Hai-Yun
authors.initials: HY
authors.lastname: Xu
authors.forename: Liang
authors.initials: L
authors.lastname: Fang
authors.forename: Yi-Tao
authors.initials: YT
authors.lastname: Ding
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005290:Ferric Compounds / Q000737:chemistry / Q000378:metabolism; D008099:Liver / Q000166:cytology / Q000293:injuries* / Q000601:surgery*; D008280:Magnetics; D045164:Mesenchymal Stem Cell Transplantation / Q000379:methods*; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000502:physiology*; D053768:Metal Nanoparticles / Q000737:chemistry; D011897:Random Allocation; D013552:Swine; D014182:Transplantation, Autologous
chemical_list: D005290:Ferric Compounds; C000499:ferric oxide