title: MR-guided portal vein delivery and monitoring of magnetocapsules: assessment of physiologic effects on the liver.
abstract: OBJECTIVE
  The authors previously developed magnetic resonance (MR)-trackable magnetocapsules (MCs) that can simultaneously immunoprotect human islet cells and noninvasively monitor portal delivery and engraftment in real time with MR imaging. This study was designed to assess the physiologic effects of the delivery of a clinical dose of MCs (140,000 capsules) into the portal vein (PV) in swine over a 1-month period.
  
  
  METHODS
  MCs were formed by using clinical-grade alginate mixed with a clinically applicable dosage of ferumoxide. Percutaneous access into the PV was obtained by using a custom-built, MR-trackable needle, and 140,000 MCs were delivered under MR guidance in five swine. Portal pressures and liver function data were obtained over a 4-week period.
  
  
  RESULTS
  A transient increase in portal pressure occurred immediately after MC delivery that returned to normal levels by 4 weeks after MC delivery. Liver function test results were normal during the entire period, and the appearance of the MCs on MR imaging did not change.
  
  
  CONCLUSIONS
  A clinically applicable dose of 140,000 MCs has no adverse effects on portal pressures or liver function in this normal swine model during the first month after delivery.
authors.affiliation: Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Link
authors.forename: David
authors.initials: D
authors.lastname: Woodrum
authors.forename: Wesley D
authors.initials: WD
authors.lastname: Gilson
authors.forename: Li
authors.initials: L
authors.lastname: Pan
authors.forename: Di
authors.initials: D
authors.lastname: Qian
authors.forename: Dara L
authors.initials: DL
authors.lastname: Kraitchman
authors.forename: Jeff W M
authors.initials: JW
authors.lastname: Bulte
authors.forename: Aravind
authors.initials: A
authors.lastname: Arepally
authors.forename: Clifford R
authors.initials: CR
authors.lastname: Weiss
mesh_terms: D000464:Alginates / Q000008:administration & dosage*; D000818:Animals; D002214:Capsules; D003287:Contrast Media; D003911:Dextrans / Q000008:administration & dosage*; D019786:Gadolinium DTPA; D020723:Glucuronic Acid / Q000008:administration & dosage; D006603:Hexuronic Acids / Q000008:administration & dosage; D007275:Injections, Intravenous; D016381:Islets of Langerhans Transplantation / Q000379:methods*; D008099:Liver / Q000098:blood supply* / Q000378:metabolism; D008111:Liver Function Tests; D018810:Magnetic Resonance Angiography; D053783:Magnetic Resonance Imaging, Interventional; D008280:Magnetics; D058185:Magnetite Nanoparticles / Q000008:administration & dosage*; D057054:Molecular Imaging / Q000379:methods*; D017082:Portal Pressure; D011169:Portal Vein; D011677:Punctures; D013552:Swine; D013997:Time Factors
chemical_list: D000464:Alginates; D002214:Capsules; D003287:Contrast Media; D003911:Dextrans; D006603:Hexuronic Acids; D058185:Magnetite Nanoparticles; D020723:Glucuronic Acid; C065507:ferumoxides; D019786:Gadolinium DTPA