title: [Sinerem labeling and MRI tracking of neural stem cells in vivo and in vitro].
abstract: OBJECTIVE
  To label rat neural stem cells (NSCs) with the complex of Sinerem, the ultrasmall superparamagnetic iron oxide (USPIO), and poly-L-lysine (PLL), and evaluate the feasibility of tracking the labeled cells with magnetic resonance imaging (MRI) in vitro and in vivo.
  
  
  METHODS
  Sinerem was incubated with PLL to obtain the complex of Sinerem-PLL. The mesenchymal stem cells (MSCs) isolated from the bone marrow of SD rats were cultured and induced to differentiate into the neural stem cells. The second-passage cells were cultured overnight with the Sinerem-PLL complex, after which Prussian blue staining and transmission electron microscopy were performed to observe the nanoparticles in the cytoplasm. Cell apoptosis assay was performed to assess the cell viability 1 day, 1 week, and 2 weeks after the labeling. Cell tracking with 4.7 MR system was carried out in vivo and in vitro using T(2)WI and T(2)*WI sequences.
  
  
  RESULTS
  The NSCs could be effectively labeled with Sinerem-PLL complex with the labeling efficiency exceeding 95%. Prussian blue staining showed numerous blue iron particles in the cytoplasm, and under transmission electron microscope, these particles accumulated in the endosomes/lysosomes. The labeling did not significantly affect the cell viability and proliferation. Remarkable low signal density changes of the labeled cells was seen on T(2)WI and T(2)*WI in vivo and in vitro.
  
  
  CONCLUSIONS
  NSCs can be effectively labeled with Sinerem-PLL complex, and MRI can be used to track the labeled cells in vivo and in vitro.
authors.affiliation: Department of Neurosurgery and Institute of Neuroscience of Guangdong Province, Zhujiang Hospital, Southern Medical University, Guangzhou 510282, China. chenzhongcan @163.com
authors.forename: Zhong-can
authors.initials: ZC
authors.lastname: Chen
authors.forename: Ru-xiang
authors.initials: RX
authors.lastname: Xu
authors.forename: Zhi-jun
authors.initials: ZJ
authors.lastname: Yang
authors.forename: Juan
authors.initials: J
authors.lastname: Fan
authors.forename: Jun-gang
authors.initials: JG
authors.lastname: Xiu
authors.forename: Guang-hui
authors.initials: GH
authors.lastname: Dai
authors.forename: Xiao-dan
authors.initials: XD
authors.lastname: Jiang
authors.forename: Li
authors.initials: L
authors.lastname: Wei
authors.forename: Hao
authors.initials: H
authors.lastname: Lei
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002478:Cells, Cultured; D003911:Dextrans / Q000378:metabolism*; D011992:Endosomes / Q000378:metabolism; D052203:Ferrosoferric Oxide / Q000378:metabolism*; D008247:Lysosomes / Q000378:metabolism; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles; D008297:Male; D059630:Mesenchymal Stem Cells / Q000166:cytology; D046529:Microscopy, Electron, Transmission; D009474:Neurons / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D011107:Polylysine / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D013997:Time Factors
chemical_list: D003911:Dextrans; D058185:Magnetite Nanoparticles; C097921:ferumoxtran-10; D011107:Polylysine; D052203:Ferrosoferric Oxide