title: Perfluorocarbon particle size influences magnetic resonance signal and immunological properties of dendritic cells.
abstract: The development of cellular tracking by fluorine ((19)F) magnetic resonance imaging (MRI) has introduced a number of advantages for following immune cell therapies in vivo. These include improved signal selectivity and a possibility to correlate cells labeled with fluorine-rich particles with conventional anatomic proton ((1)H) imaging. While the optimization of the cellular labeling method is clearly important, the impact of labeling on cellular dynamics should be kept in mind. We show by (19)F MR spectroscopy (MRS) that the efficiency in labeling cells of the murine immune system (dendritic cells) by perfluoro-15-crown-5-ether (PFCE) particles increases with increasing particle size (560>365>245>130 nm). Dendritic cells (DC) are professional antigen presenting cells and with respect to impact of PFCE particles on DC function, we observed that markers of maturation for these cells (CD80, CD86) were also significantly elevated following labeling with larger PFCE particles (560 nm). When labeled with these larger particles that also gave an optimal signal in MRS, DC presented whole antigen more robustly to CD8+ T cells than control cells. Our data suggest that increasing particle size is one important feature for optimizing cell labeling by PFCE particles, but may also present possible pitfalls such as alteration of the immunological status of these cells. Therefore depending on the clinical scenario in which the (19)F-labeled cellular vaccines will be applied (cancer, autoimmune disease, transplantation), it will be interesting to monitor the fate of these cells in vivo in the relevant preclinical mouse models.
authors.affiliation: Max Delbrück Center for Molecular Medicine and Charité Medical Faculty, Berlin, Germany.
authors.forename: Helmar
authors.initials: H
authors.lastname: Waiczies
authors.forename: Stefano
authors.initials: S
authors.lastname: Lepore
authors.forename: Nicole
authors.initials: N
authors.lastname: Janitzek
authors.forename: Ulrike
authors.initials: U
authors.lastname: Hagen
authors.forename: Frank
authors.initials: F
authors.lastname: Seifert
authors.forename: Bernd
authors.initials: B
authors.lastname: Ittermann
authors.forename: Bettina
authors.initials: B
authors.lastname: Purfürst
authors.forename: Antonio
authors.initials: A
authors.lastname: Pezzutto
authors.forename: Friedemann
authors.initials: F
authors.lastname: Paul
authors.forename: Thoralf
authors.initials: T
authors.lastname: Niendorf
authors.forename: Sonia
authors.initials: S
authors.lastname: Waiczies
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D048430:Cell Shape; D003713:Dendritic Cells / Q000166:cytology* / Q000276:immunology*; D004655:Emulsions; D005466:Fluorocarbons / Q000737:chemistry*; D008279:Magnetic Resonance Imaging; D051379:Mice; D008810:Mice, Inbred C57BL; D010316:Particle Size; D010587:Phagocytosis / Q000276:immunology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology
chemical_list: D004655:Emulsions; D005466:Fluorocarbons