title: Magnetic resonance imaging monitoring dual-labeled stem cells for treatment of mouse nerve injury.
abstract: OBJECTIVE
  Adipose-derived stem cells (ADSCs) have shown great promise in the regenerative repair of injured peripheral nerves. Magnetic resonance imaging (MRI) has provided attractive advantages in tracking superparamagnetic iron oxide nanoparticle (SPION)-labeled cells and evaluating their fate after cell transplantation. This study investigated the feasibility of the use of MRI to noninvasively track ADSCs repair of peripheral nerve injury in vivo.
  
  
  METHODS
  Green fluorescent protein (GFP)-expressing ADSCs were isolated, expanded, differentiated into an SC-like phenotype (GFP-dADSCs) at early passages and subsequently labeled with SPIONs. The morphological and functional properties of the GFP-dADSCs were assessed through the use of immunohistochemistry. The intracellular stability, proliferation and viability of the labeled cells were evaluated in vitro. Through the use of a microsurgical procedure, the labeled cells were then seeded into sciatic nerve conduits in C57/BL6 mice to repair a 1-cm sciatic nerve gap. A clinical 3-T MRI was performed to investigate the GFP-dADSCs in vitro and the transplanted GFP-dADSCs inside the sciatic nerve conduits in vivo.
  
  
  RESULTS
  The GFP-dADSCs were efficiently labeled with SPIONs, without affecting their viability and proliferation. The labeled cells implanted into the mice sciatic nerve conduit exhibited a significant increase in axonal regeneration compared with the empty conduit and could be detected by MRI. Fluorescent microscopic examination, histological analysis and immunohistochemistry confirmed the axon regeneration and MRI results.
  
  
  CONCLUSIONS
  These data will elucidate the neuroplasticity of ADSCs and provide a new protocol for in vivo tracking of stem cells that are seeded to repair injured peripheral nerves.
authors.affiliation: Department of Radiology, Shanghai First People's Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, People's Republic of China. kanganli@gmail.com
authors.forename: Kangan
authors.initials: K
authors.lastname: Li
authors.forename: Jinbao
authors.initials: J
authors.lastname: Qin
authors.forename: Xifu
authors.initials: X
authors.lastname: Wang
authors.forename: Yanhong
authors.initials: Y
authors.lastname: Xu
authors.forename: Zunli
authors.initials: Z
authors.lastname: Shen
authors.forename: Xinwu
authors.initials: X
authors.lastname: Lu
authors.forename: Guixiang
authors.initials: G
authors.lastname: Zhang
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D053687:Adult Stem Cells / Q000166:cytology / Q000000981:diagnostic imaging / Q000378:metabolism*; D000818:Animals; D049109:Cell Proliferation; D002470:Cell Survival; D002478:Cells, Cultured; D005290:Ferric Compounds / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics; D007150:Immunohistochemistry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D059348:Peripheral Nerve Injuries / Q000175:diagnosis* / Q000628:therapy*; D011877:Radionuclide Imaging; D012584:Sciatic Nerve / Q000000981:diagnostic imaging* / Q000473:pathology; D013194:Staining and Labeling; D033581:Stem Cell Transplantation
chemical_list: D005290:Ferric Compounds; D049452:Green Fluorescent Proteins; C000499:ferric oxide
keywords: adipose-derived stem cells; iron oxide particles; magnetic resonance imaging; peripheral nerve injury; stem cell therapy