title: Magnetic resonance imaging of pancreatic islets transplanted into the liver in humans.
abstract: BACKGROUND
  In vitro labeling of pancreatic islets by iron nanoparticles enables their detection as hypoitnense spots on serial magnetic resonance (MR) images. We report the first results of a pilot trial aiming to test the feasibility and safety of this technique in humans.
  
  
  METHODS
  Islets were labeled in culture with 5 μL/mL ferucarbotran for 6 to 48 hr and transplanted into the portal vein (12 infusions) in 8 C-peptide negative recipients. The liver area was examined the next day and 1, 4, and 24 weeks posttransplant using a 3T MR scanner.
  
  
  RESULTS
  In all recipients, significant C-peptide levels and near-normal HbA1c values were achieved with 50% to 80% insulin dose reduction. No side effects related to the labeling procedure were documented. Typically, a significant islet spot number decrease (on average 60%) was detected at week 1 with subsequent only slight decrease for up to 24 weeks. In two subjects with labeling period of less than 6 and 10 hr, only few islet spots were detected corresponding to poor islet visualization in phantoms labeled for the same period of time.
  
  
  CONCLUSIONS
  Pancreatic islets (PI) visualization was safe and successful in all recipients but was less efficient if labeling period was less than 16 hr. Significant decrease of islet spots occurred at week 1, suggesting early islet destruction or impaired engraftment. Afterward, the islet spot numbers remained stable for up to 24 weeks. Data show that MR detection of ferucarbotran-labeled islets enables their long-term noninvasive visualization and correlates with sustained C-peptide production.
authors.affiliation: Diabetes Center, Institute for Clinical and Experimental Medicine, Prague, Czech Republic. frsa@medicon.cz
authors.forename: Frantisek
authors.initials: F
authors.lastname: Saudek
authors.forename: Daniel
authors.initials: D
authors.lastname: Jirák
authors.forename: Peter
authors.initials: P
authors.lastname: Girman
authors.forename: Vít
authors.initials: V
authors.lastname: Herynek
authors.forename: Monika
authors.initials: M
authors.lastname: Dezortová
authors.forename: Jan
authors.initials: J
authors.lastname: Kríz
authors.forename: Jan
authors.initials: J
authors.lastname: Peregrin
authors.forename: Zuzana
authors.initials: Z
authors.lastname: Berková
authors.forename: Klára
authors.initials: K
authors.lastname: Zacharovová
authors.forename: Milan
authors.initials: M
authors.lastname: Hájek
mesh_terms: D002096:C-Peptide / Q000097:blood; D003920:Diabetes Mellitus / Q000601:surgery; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007515:Islets of Langerhans / Q000033:anatomy & histology / Q000473:pathology*; D016381:Islets of Langerhans Transplantation / Q000379:methods*; D008099:Liver / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D019047:Phantoms, Imaging; D011169:Portal Vein / Q000033:anatomy & histology
chemical_list: D002096:C-Peptide; D006442:Glycated Hemoglobin