title: In vivo imaging of islet transplantation using PLGA nanoparticles containing iron oxide and indocyanine green.
abstract: OBJECTIVE
  We determined whether poly(lactic-co-glycolic acid) nanoparticles would be a useful reagent for the successful monitoring of isolated islets by magnetic resonance imaging and optical imaging systems, without clinically relevant toxicity in vitro or in vivo.
  
  
  METHODS
  We used iron oxide for MR imaging and a cyanide dye approved by the Food and Drug Administration (indocyanine green) for optical imaging and estimated the in vivo detection of transplanted pancreatic islets.
  
  
  RESULTS
  The poly(lactic-co-glycolic acid) nanoparticles were associated with the islets in vitro and were successfully detected by 4.7 T (MR) and optical imaging, without other toxic effects. When labeled islets were transplanted under the mouse kidney capsule, in vivo T2/ T2*-weighted scans with 4.7 T MR detected as few as 300 labeled islets by 4 weeks. Optical in vivo imaging revealed indocyanine green fluorescence by 2 and 4 days after transplantation of islets containing 250 and 500 µg/mL poly(lactic-co-glycolic acid) nanoparticles, respectively. These results were further supported by the immunohistochemical results for insulin and iron in the recipient mouse kidney and pancreas.
  
  
  CONCLUSIONS
  Taken together, these data indicate that poly(lactic-co-glycolic acid) nanoparticles may be used to label transplanted islets and may be imaged with in vivo MR and optical imaging systems.
authors: Laboratory Animal Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Yuseong-gu, Daejeon, Korea.
authors: Jung Hwan
authors: JH
authors: Hwang
authors: Young-Woock
authors: YW
authors: Noh
authors: Jung-Hyun
authors: JH
authors: Choi
authors: Jung-Ran
authors: JR
authors: Noh
authors: Yong-Hoon
authors: YH
authors: Kim
authors: Gil-Tae
authors: GT
authors: Gang
authors: Kyoung-Shim
authors: KS
authors: Kim
authors: Hye Sun
authors: HS
authors: Park
authors: Yong Taik
authors: YT
authors: Lim
authors: Hyeyoung
authors: H
authors: Moon
authors: Kwan Soo
authors: KS
authors: Hong
authors: Hee Gu
authors: HG
authors: Lee
authors: Bong Hyun
authors: BH
authors: Chung
authors: Chul-Ho
authors: CH
authors: Lee
mesh_terms: D000818:Animals; D058948:Cell Tracking / Q000379:methods; D002478:Cells, Cultured; D004058:Diffusion; D007089:Image Enhancement / Q000379:methods; D007208:Indocyanine Green; D007515:Islets of Langerhans / Q000166:cytology*; D016381:Islets of Langerhans Transplantation / Q000379:methods*; D019344:Lactic Acid / Q000737:chemistry*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000648:ultrastructure; D051379:Mice; D008810:Mice, Inbred C57BL; D008853:Microscopy / Q000379:methods; D053769:Nanocapsules / Q000737:chemistry / Q000648:ultrastructure; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D058185:Magnetite Nanoparticles; D053769:Nanocapsules; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D007208:Indocyanine Green