title: PET imaging of cardiac wound healing using a novel [68Ga]-labeled NGR probe in rat myocardial infarction.
abstract: OBJECTIVE
  Peptides containing the asparagine-glycine-arginine (NGR) motif bind to aminopeptidase N (CD13), which is expressed on inflammatory cells, endothelial cells, and fibroblasts. It is unclear whether radiolabeled NGR-containing tracers could be used for in vivo imaging of the early wound-healing phase after myocardial infarction (MI) using positron emission tomography (PET).
  
  
  METHODS
  Uptake of novel tracer [(68)Ga]NGR was assessed together with [(68)Ga]arginine-glycine-aspartic acid ([(68)Ga]RGD) and 2-deoxy-2-[(18) F]fluoro-D-glucose after myocardial ischemia/reperfusion (MI/R) injury using μ-PET and autoradiography, and relative expressions of CD13 and integrin β3 were assessed in fibroblasts, inflammatory cells, and endothelial cells by immunohistochemistry.
  
  
  RESULTS
  In the infarcted myocardium, uptake of [(68)Ga]NGR was maximal from days 3 to 7 after MI/R, and correlated with fibroblast and inflammatory cell infiltration as well as [(68)Ga]RGD uptake.
  
  
  CONCLUSIONS
  [(68)Ga]NGR allows noninvasive and sequential determination of CD13 expression in fibroblasts and inflammatory cells by PET. This will facilitate monitoring of CD13 in the individual wound healing processes, allowing patient-specific therapies to improve outcome after MI.
authors.affiliation: Department of Cardiology and Angiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany, tillmanns.jochen@mh-hannover.de.
authors.forename: Jochen
authors.initials: J
authors.lastname: Tillmanns
authors.forename: Magdalena
authors.initials: M
authors.lastname: Schneider
authors.forename: Daniela
authors.initials: D
authors.lastname: Fraccarollo
authors.forename: Jan-Dieter
authors.initials: JD
authors.lastname: Schmitto
authors.forename: Florian
authors.initials: F
authors.lastname: Länger
authors.forename: Dominik
authors.initials: D
authors.lastname: Richter
authors.forename: Johann
authors.initials: J
authors.lastname: Bauersachs
authors.forename: Samuel
authors.initials: S
authors.lastname: Samnick
mesh_terms: D020816:Amino Acid Motifs; D000818:Animals; D018826:CD13 Antigens / Q000378:metabolism; D005347:Fibroblasts / Q000000981:diagnostic imaging / Q000473:pathology; D005710:Gallium Radioisotopes; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D007150:Immunohistochemistry; D007249:Inflammation; D008297:Male; D009203:Myocardial Infarction / Q000000981:diagnostic imaging*; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging; D009206:Myocardium / Q000473:pathology; D009842:Oligopeptides / Q000737:chemistry; D049268:Positron-Emission Tomography; D051381:Rats; D017208:Rats, Wistar; D014945:Wound Healing
chemical_list: D005710:Gallium Radioisotopes; C526428:NGR peptide; D009842:Oligopeptides; D018826:CD13 Antigens