title: Clinical cell therapy imaging using a perfluorocarbon tracer and fluorine-19 MRI.
abstract: OBJECTIVE
  Cellular therapeutics are emerging as a treatment option for a host of serious human diseases. To accelerate clinical translation, noninvasive imaging of cell grafts in clinical trials can potentially be used to assess the initial delivery and behavior of cells.
  
  
  METHODS
  The use of a perfluorocarbon (PFC) tracer agent for clinical fluorine-19 ((19) F) MRI cell detection is described. This technology was used to detect immunotherapeutic dendritic cells (DCs) delivered to colorectal adenocarcinoma patients. Autologous DC vaccines were labeled with a PFC MRI agent ex vivo. Patients received DCs intradermally, and (19) F spin-density-weighted MRI at 3 Tesla (T) was used to observe cells.
  
  
  RESULTS
  Spin-density-weighted (19) F images at the injection site displayed DCs as background-free "hot-spot" images. (19) F images were acquired in clinically relevant scan times (<10 min). Apparent DC numbers could be quantified in two patients from the (19) F hot-spots and were observed to decrease by ∼50% at injection site by 24 h. From 3T phantom studies, the sensitivity limit for DC detection is estimated to be on the order of ∼10(5) cells/voxel in this study.
  
  
  CONCLUSIONS
  These results help to establish a clinically applicable means to track a broad range of cell types used in cell therapy.
authors.affiliation: Department of Radiology, University of California at San Diego, La Jolla, California, USA.
authors.forename: Eric T
authors.initials: ET
authors.lastname: Ahrens
authors.forename: Brooke M
authors.initials: BM
authors.lastname: Helfer
authors.forename: Charles F
authors.initials: CF
authors.lastname: O'Hanlon
authors.forename: Claudiu
authors.initials: C
authors.lastname: Schirda
mesh_terms: D000328:Adult; D000368:Aged; D058948:Cell Tracking / Q000379:methods*; D002478:Cells, Cultured; D015179:Colorectal Neoplasms / Q000276:immunology / Q000473:pathology* / Q000628:therapy*; D003287:Contrast Media / Q000008:administration & dosage; D003713:Dendritic Cells / Q000276:immunology / Q000473:pathology* / Q000637:transplantation*; D005240:Feasibility Studies; D005260:Female; D066235:Fluorine-19 Magnetic Resonance Imaging / Q000379:methods*; D005466:Fluorocarbons / Q000008:administration & dosage; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D025321:Surgery, Computer-Assisted / Q000379:methods; D016896:Treatment Outcome
chemical_list: D003287:Contrast Media; D005466:Fluorocarbons
keywords: 19F; MRI; cancer; cell tracking; dendritic cells; fluorine-19; immunotherapy; perfluorcarbon