title: In vivo detection of embryonic stem cell-derived cardiovascular progenitor cells using Cy3-labeled Gadofluorine M in murine myocardium.
abstract: OBJECTIVE
  The aim of the current study is to test the ability to label and detect murine embryonic stem cell-derived cardiovascular progenitor cells (ES-CPC) with cardiac magnetic resonance (CMR) using the novel contrast agent Gadofluorine M-Cy3 (GdFM-Cy3).
  
  
  BACKGROUND
  Cell therapy shows great promise for the treatment of cardiovascular disease. An important limitation to previous clinical studies is the inability to accurately identify transplanted cells. GdFM-Cy3 is a lipophilic paramagnetic contrast agent that contains a perfluorinated side chain and an amphiphilic character that allows for micelle formation in an aqueous solution. Previous studies reported that it is easily taken up and stored within the cytosol of mesenchymal stem cells, thereby allowing for paramagnetic cell labeling. Investigators in our laboratory have recently developed techniques for the robust generation of ES-CPC. We reasoned that GdFM-Cy3 would be a promising agent for the in vivo detection of these cells after cardiac cell transplantation.
  
  
  METHODS
  ES-CPC were labeled with GdFM-Cy3 by incubation. In vitro studies were performed to assess the impact of GdFM-Cy3 on cell function and survival. A total of 500,000 GdFM-Cy3-labeled ES-CPC or control ES-CPC were injected into the myocardium of mice with and without myocardial infarction. Mice were imaged (9.4-T) before and over a 2-week time interval after stem cell transplantation. Mice were then euthanized, and their hearts were sectioned for fluorescence microscopy.
  
  
  RESULTS
  In vitro studies demonstrated that GdFM-Cy3 was easily transfectable, nontoxic, stayed within cells after labeling, and could be visualized using CMR and fluorescence microscopy. In vivo studies confirmed the efficacy of the agent for the detection of cells transplanted into the hearts of mice after myocardial infarction. A correspondence between CMR and histology was observed.
  
  
  CONCLUSIONS
  The results of the current study suggest that it is possible to identify and potentially track GdFM-Cy3-labeled ES-CPC in murine infarct models via CMR.
authors.affiliation: Cardiovascular Institute and Department of Medicine, Mount Sinai School of Medicine, New York, New York 10029, USA. eric.adler@mssm.edu
authors.forename: Eric D
authors.initials: ED
authors.lastname: Adler
authors.forename: Anne
authors.initials: A
authors.lastname: Bystrup
authors.forename: Karen C
authors.initials: KC
authors.lastname: Briley-Saebo
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Mani
authors.forename: Wilson
authors.initials: W
authors.lastname: Young
authors.forename: Steven
authors.initials: S
authors.lastname: Giovanonne
authors.forename: Perry
authors.initials: P
authors.lastname: Altman
authors.forename: Steven J
authors.initials: SJ
authors.lastname: Kattman
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Frank
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Weinmann
authors.forename: Gordon M
authors.initials: GM
authors.lastname: Keller
authors.forename: Zahi A
authors.initials: ZA
authors.lastname: Fayad
mesh_terms: D000818:Animals; D002232:Carbocyanines / Q000378:metabolism* / Q000633:toxicity; D002460:Cell Line; D049109:Cell Proliferation; D002470:Cell Survival; D003287:Contrast Media / Q000378:metabolism* / Q000633:toxicity; D004195:Disease Models, Animal; D053595:Embryonic Stem Cells / Q000378:metabolism / Q000637:transplantation*; D005260:Female; D005456:Fluorescent Dyes / Q000378:metabolism* / Q000633:toxicity; D005466:Fluorocarbons; D008279:Magnetic Resonance Imaging; D045164:Mesenchymal Stem Cell Transplantation; D051379:Mice; D016513:Mice, SCID; D008856:Microscopy, Fluorescence; D009203:Myocardial Infarction / Q000378:metabolism / Q000473:pathology / Q000601:surgery*; D009206:Myocardium / Q000378:metabolism / Q000473:pathology*; D032383:Myocytes, Cardiac / Q000378:metabolism / Q000637:transplantation*; D009942:Organometallic Compounds / Q000378:metabolism* / Q000633:toxicity; D013194:Staining and Labeling / Q000379:methods*; D013997:Time Factors
chemical_list: D002232:Carbocyanines; D003287:Contrast Media; D005456:Fluorescent Dyes; D005466:Fluorocarbons; D009942:Organometallic Compounds; C089187:cyanine dye 3; C517961:gadofluorine M