Cell type-specific response to high intracellular loading of polyacrylic acid-coated magnetic nanoparticles.
Magnetic nanoparticles (NPs) are a special type of NP with a ferromagnetic, electron-dense core that enables several applications such as cell tracking, hyperthermia, and magnetic separation, as well as multimodality. So far, superparamagnetic iron oxide NPs (SPIONs) are the only clinically approved type of metal oxide NPs, but cobalt ferrite NPs have properties suitable for biomedical applications as well. In this study, we analyzed the cellular responses to magnetic cobalt ferrite NPs coated with polyacrylic acid (PAA) in three cell types: Chinese Hamster Ovary (CHO), mouse melanoma (B16) cell line, and primary human myoblasts (MYO). We compared the internalization pathway, intracellular trafficking, and intracellular fate of our NPs using fluorescence and transmission electron microscopy (TEM) as well as quantified NP uptake and analyzed uptake dynamics. We determined cell viability after 24 or 96 hours' exposure to increasing concentrations of NPs, and quantified the generation of reactive oxygen species (ROS) upon 24 and 48 hours' exposure. Our NPs have been shown to readily enter and accumulate in cells in high quantities using the same two endocytic pathways; mostly by macropinocytosis and partially by clathrin-mediated endocytosis. The cell types differed in their uptake rate, the dynamics of intracellular trafficking, and the uptake capacity, as well as in their response to higher concentrations of internalized NPs. The observed differences in cell responses stress the importance of evaluation of NP-cell interactions on several different cell types for better prediction of possible toxic effects on different cell and tissue types in vivo.
Group for Nano and Biotechnological Applications, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia.
Jasna
J
Lojk
Group for Nano and Biotechnological Applications, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia.
Vladimir B
VB
Bregar
Group for Nano and Biotechnological Applications, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia.
Maruša
M
Rajh
Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
Katarina
K
Miš
Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
Mateja Erdani
ME
Kreft
Institute of Pathophysiology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
Sergej
S
Pirkmajer
Institute of Cell Biology, Faculty of Medicine, University of Ljubljana, Ljubljana, Slovenia.
Peter
P
Veranič
Group for Nano and Biotechnological Applications, Faculty of Electrical Engineering, University of Ljubljana, Ljubljana, Slovenia.
Mojca
M
Pavlin
D000180:Acrylic Resins / Q000737:chemistry / Q000633:toxicity; D000818:Animals; D016466:CHO Cells; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003035:Cobalt / Q000737:chemistry / Q000633:toxicity; D006224:Cricetinae; D003412:Cricetulus; D004705:Endocytosis / Q000187:drug effects*; D006801:Humans; D058185:Magnetite Nanoparticles / Q000737:chemistry / Q000633:toxicity; D051379:Mice
D000180:Acrylic Resins; D058185:Magnetite Nanoparticles; D003035:Cobalt; C006903:carbopol 940
ROS; cell viability; intracellular fate; transmission electron microscopy; uptake quantification