title: [18F]-FBEM, a tracer targeting cell-surface protein thiols for cell trafficking imaging.
abstract: We used [(18)F]-4-fluorobenzamido-N-ethylamino-maleimide ([(18)F]-FBEM) to radiolabel cells ex vivo for in vivo positron emission tomography (PET) in order to assess cell trafficking in mice. In contrast to commonly used imaging agents, [(18)F]-FBEM forms a covalent bond with thiol groups present on the cells surface. The stability of the probe in aqueous medium was tested at different pH values and cross-experiment showed that thiol-labeling efficiency was retained (at least) up to pH 9. The labeling procedure did not affect significantly the cell viability. To illustrate the procedure, PET images of living mice injected intravenously with labeled T lymphocytes were obtained. They showed the expected cell homing in the spleen that was absent in mice injected with free label.
authors.affiliation: PET/Biomedical Cyclotron Unit and Department of Nuclear Medicine, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium. slacroix@ulb.ac.be
authors.forename: Simon
authors.initials: S
authors.lastname: Lacroix
authors.forename: Dominique
authors.initials: D
authors.lastname: Egrise
authors.forename: Gaetan
authors.initials: G
authors.lastname: Van Simaeys
authors.forename: Gilles
authors.initials: G
authors.lastname: Doumont
authors.forename: M
authors.initials: M
authors.lastname: Monclus
authors.forename: F
authors.initials: F
authors.lastname: Sherer
authors.forename: T
authors.initials: T
authors.lastname: Herbaux
authors.forename: D
authors.initials: D
authors.lastname: Leroy
authors.forename: Serge
authors.initials: S
authors.lastname: Goldman
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D058948:Cell Tracking; D005462:Fluorine Radioisotopes; D008301:Maleimides / Q000008:administration & dosage / Q000737:chemistry; D051379:Mice; D008819:Mice, Nude; D049268:Positron-Emission Tomography; D011868:Radioisotopes; D013194:Staining and Labeling; D013438:Sulfhydryl Compounds / Q000737:chemistry / Q000302:isolation & purification*; D013499:Surface Properties; D013601:T-Lymphocytes / Q000737:chemistry / Q000648:ultrastructure*; D014018:Tissue Distribution
chemical_list: D005462:Fluorine Radioisotopes; D008301:Maleimides; C512447:N-(2-(4-18F-fluorobenzamido)ethyl)maleimide; D011868:Radioisotopes; D013438:Sulfhydryl Compounds