title: Choose your cell model wisely: The in vitro nanoneurotoxicity of differentially coated iron oxide nanoparticles for neural cell labeling.
abstract: Currently, there is a large interest in the labeling of neural stem cells (NSCs) with iron oxide nanoparticles (IONPs) to allow MRI-guided detection after transplantation in regenerative medicine. For such biomedical applications, excluding nanotoxicity is key. Nanosafety is primarily evaluated in vitro where an immortalized or cancer cell line of murine origin is often applied, which is not necessarily an ideal cell model. Previous work revealed clear neurotoxic effects of PMA-coated IONPs in distinct cell types that could potentially be applied for nanosafety studies regarding neural cell labeling. Here, we aimed to assess if DMSA-coated IONPs could be regarded as a safer alternative for this purpose and how the cell model impacted our nanosafety optimization study. Hereto, we evaluated cytotoxicity, ROS production, calcium levels, mitochondrial homeostasis and cell morphology in six related neural cell types, namely neural stem cells, an immortalized cell line and a cancer cell line from human and murine origin. The cell lines mostly showed similar responses to both IONPs, which were frequently more pronounced for the PMA-IONPs. Of note, ROS and calcium levels showed opposite trends in the human and murine NSCs, indicating the importance of the species. Indeed, the human cell models were overall more sensitive than their murine counterpart. Despite the clear cell type-specific nanotoxicity profiles, our multiparametric approach revealed that the DMSA-IONPs outperformed the PMA-IONPs in terms of biocompatibility in each cell type. However, major cell type-dependent variations in the observed effects additionally warrant the use of relevant human cell models.
  
  
  
  Inorganic nanoparticle (NP) optimization is chiefly performed in vitro. For the optimization of iron oxide (IO)NPs for neural stem cell labeling in the context of regenerative medicine human or rodent neural stem cells, immortalized or cancer cell lines are applied. However, the use of certain cell models can be questioned as they phenotypically differ from the target cell. The impact of the neural cell model on nanosafety remains relatively unexplored. Here we evaluated cell homeostasis upon exposure to PMA- and DMSA-coated IONPs. Of note, the DMSA-IONPs outperformed the PMA-IONPs in each cell type. However, distinct cell type-specific effects were witnessed, indicating that nanosafety should be evaluated in a human cell model that represents the target cell as closely as possible.
authors.affiliation: Lab of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, B-9000 Ghent, Belgium.
authors.forename: Freya
authors.initials: F
authors.lastname: Joris
authors.affiliation: Philipps University of Marburg, Department of Physics, Renthof 7, D-35037 Marburg, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Valdepérez
authors.affiliation: Philipps University of Marburg, Department of Physics, Renthof 7, D-35037 Marburg, Germany.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Pelaz
authors.affiliation: Philipps University of Marburg, Department of Physics, Renthof 7, D-35037 Marburg, Germany.
authors.forename: Tianqiang
authors.initials: T
authors.lastname: Wang
authors.affiliation: Institute of Life Sciences, Swansea University Medical School, Singleton Park, Swansea, Wales SA2 8PP, UK.
authors.forename: Shareen H
authors.initials: SH
authors.lastname: Doak
authors.affiliation: Biomedical MRI Unit/MoSAIC, Department of Medicine, KULeuven, Herestraat 49, B-3000 Leuven, Belgium.
authors.forename: Bella B
authors.initials: BB
authors.lastname: Manshian
authors.affiliation: Biomedical MRI Unit/MoSAIC, Department of Medicine, KULeuven, Herestraat 49, B-3000 Leuven, Belgium.
authors.forename: Stefaan J
authors.initials: SJ
authors.lastname: Soenen
authors.affiliation: Philipps University of Marburg, Department of Physics, Renthof 7, D-35037 Marburg, Germany.
authors.forename: Wolfgang J
authors.initials: WJ
authors.lastname: Parak
authors.affiliation: Lab of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, B-9000 Ghent, Belgium. Electronic address: stefaan.desmedt@ugent.be.
authors.forename: Stefaan C
authors.initials: SC
authors.lastname: De Smedt
authors.affiliation: Lab of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Ottergemsesteenweg 460, B-9000 Ghent, Belgium.
authors.forename: Koen
authors.initials: K
authors.lastname: Raemdonck
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D045744:Cell Line, Tumor; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000494:pharmacology; D006801:Humans; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D008422:Materials Testing; D051379:Mice; D008928:Mitochondria / Q000378:metabolism; D058953:Neural Stem Cells / Q000166:cytology / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D013194:Staining and Labeling / Q000379:methods*
chemical_list: D020099:Coated Materials, Biocompatible; D058185:Magnetite Nanoparticles; D017382:Reactive Oxygen Species; D002118:Calcium
keywords: Cell line; DMSA; IONP; Multiparametric; Neural stem cell; PMA