Aims: We validated novel bimodal iron oxide particles as substitute of ferumoxides for efficient labeling of human neural stem cells (NSCs). The dextrane-coated FeraTrack Direct (FTD)-Vio particles have additional far-red fluorophores for microscopic cell analysis.
Methods: MR relaxometry, spectrophotometric iron determination and microscopy are used for characterization in vitro and in vivo.
Results: Efficient uptake is not transfection agent-dependent. FTD-Vio594 labeling had no influence on viability, proliferation, migration and differentiation capacity. It allows MRI-based tracking of engrafted NSCs in mouse brain up to 11 days, complemented by bioluminescence imaging of firefly luciferase expressed by the engrafted cells.
Conclusion: Our results highlight the FTD-Vio594 particles as safe and sensitive substitute of ferumoxides for longitudinal tracking of NSCs in preclinical studies.
Keywords: MRI; bioluminescence imaging; cell tracking; iron oxide nanoparticle; neural stem cells.