title: Use of perfluorocarbon nanoparticles for non-invasive multimodal cell tracking of human pancreatic islets.
abstract: In vivo imaging of engraftment and immunorejection of transplanted islets is critical for further clinical development, with (1)H MR imaging of superparamagnetic iron oxide-labeled cells being the current premier modality. Using perfluorocarbon nanoparticles, we present here a strategy for non-invasive imaging of cells using other modalities. To this end, human cadaveric islets were labeled with rhodamine-perfluorooctylbromide (PFOB) nanoparticles, rhodamine-perfluoropolyether (PFPE) nanoparticles or Feridex as control and tested in vitro for cell viability and c-peptide secretion for 1 week. (19)F MRI, computed tomography (CT) and ultrasound (US) imaging was performed on labeled cell phantoms and on cells following transplantation beneath the kidney capsule of mice and rabbits. PFOB and PFPE-labeling did not reduce human islet viability or glucose responsiveness as compared with unlabeled cells or SPIO-labeled cells. PFOB- and PFPE-labeled islets were effectively fluorinated for visualization by (19)F MRI. PFOB-labeled islets were acoustically reflective for detection by US imaging and became sufficiently brominated to become radiopaque allowing visualization with CT. Thus, perfluorocarbon nanoparticles are multimodal cellular contrast agents that may find applications in real-time targeted delivery and imaging of transplanted human islets or other cells in a clinically applicable manner using MRI, US or CT imaging.
authors.affiliation: Department of Radiology and Radiological Science, Division of MR Research, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
authors.forename: Brad P
authors.initials: BP
authors.lastname: Barnett
authors.forename: Jesus
authors.initials: J
authors.lastname: Ruiz-Cabello
authors.forename: Partha
authors.initials: P
authors.lastname: Hota
authors.forename: Ronald
authors.initials: R
authors.lastname: Ouwerkerk
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Shamblott
authors.forename: Cal
authors.initials: C
authors.lastname: Lauzon
authors.forename: Piotr
authors.initials: P
authors.lastname: Walczak
authors.forename: Wesley D
authors.initials: WD
authors.lastname: Gilson
authors.forename: Vadappuram P
authors.initials: VP
authors.lastname: Chacko
authors.forename: Dara L
authors.initials: DL
authors.lastname: Kraitchman
authors.forename: Aravind
authors.initials: A
authors.lastname: Arepally
authors.forename: Jeff W M
authors.initials: JW
authors.lastname: Bulte
mesh_terms: D000818:Animals; D058948:Cell Tracking / Q000379:methods*; D005466:Fluorocarbons / Q000737:chemistry*; D006801:Humans; D066298:In Vitro Techniques; D007515:Islets of Langerhans / Q000166:cytology*; D008279:Magnetic Resonance Imaging / Q000379:methods; D051379:Mice; D008810:Mice, Inbred C57BL; D053758:Nanoparticles / Q000737:chemistry*; D011817:Rabbits
chemical_list: D005466:Fluorocarbons