title: Migration of iron-labeled KHYG-1 natural killer cells to subcutaneous tumors in nude mice, as detected by magnetic resonance imaging.
abstract: OBJECTIVE
  A novel cell line of cytotoxic natural killer (NK) cells, KHYG-1, was examined in vivo for immunotherapy against prostate cancer. The feasibility of using magnetic resonance imaging (MRI) tracking to monitor the fate of injected NK cells following intravenous (i.v.), intraperitoneal (i.p.) and subcutaneous (s.c.) administration was assessed.
  
  
  METHODS
  PC-3M human prostate cancer cells were injected s.c. into the flank of nude mice (day 0). KHYG-1 NK cells were labeled with an iron oxide contrast agent and injected s.c., i.v. or i.p. on day 8. Mice were imaged by MRI on days 7, 9 and 12. Tumor sections were examined with fluorescence microscopy and immunohistologic staining for NK cells.
  
  
  RESULTS
  NK cells were detected in the tumors by histology after all three administration routes. NK cells and fluorescence from the iron label were co-localized. Signal loss was seen in the areas around the tumors and between the tumor lobes in the s.c. group.
  
  
  CONCLUSIONS
  We are the first to label this cell line of NK cells with an iron oxide contrast agent. Accumulation of NK cells was visualized by MRI after s.c. injection but not after i.v. and i.p. injection.
authors.affiliation: Imaging Research Laboratories, Robarts Research Institute, London, Ontario, Canada.
authors.forename: Christiane L
authors.initials: CL
authors.lastname: Mallett
authors.forename: Catherine
authors.initials: C
authors.lastname: McFadden
authors.forename: Yuhua
authors.initials: Y
authors.lastname: Chen
authors.forename: Paula J
authors.initials: PJ
authors.lastname: Foster
mesh_terms: D000818:Animals; D016923:Cell Death; D045744:Cell Line, Tumor; D002465:Cell Movement; D002470:Cell Survival; D006801:Humans; D007501:Iron; D007694:Killer Cells, Natural / Q000166:cytology* / Q000276:immunology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D051379:Mice; D008819:Mice, Nude; D009369:Neoplasms / Q000276:immunology* / Q000473:pathology; D012815:Signal Processing, Computer-Assisted; D013194:Staining and Labeling; D040521:Subcutaneous Tissue / Q000276:immunology / Q000473:pathology*
chemical_list: D007501:Iron