Revelation of Different Nanoparticle-Uptake Behavior in Two Standard Cell Lines NIH/3T3 and A549 by Flow Cytometry and Time-Lapse Imaging
Institute of Technical Chemistry, Gottfried Wilhelm Leibniz Universität Hannover, 30167 Hannover, Germany
Laboratory “Photoactive Nanocomposite Materials” (Director), Saint-Petersburg State University, 198504 Saint-Petersburg, Russia
Author to whom correspondence should be addressed.
These authors contributed equally to this work.
Academic Editor: Thomas Webster
Toxics 2017, 5(3), 15; https://doi.org/10.3390/toxics5030015
Received: 31 May 2017 / Revised: 6 July 2017 / Accepted: 17 July 2017 / Published: 19 July 2017
(This article belongs to the Special Issue Health Effects of Airborne Particles, Gases and Aerosols: Current and Future Perspectives)
The uptake of nanomaterials into different cell types is a central pharmacological issue for the determination of nanotoxicity as well as for the development of drug delivery strategies. Most responses of the cells depend on their intracellular interactions with nanoparticles (NPs). Uptake behavior can be precisely investigated in vitro, with sensitive high throughput methods such as flow cytometry. In this study, we investigated two different standard cell lines, human lung carcinoma (A549) and mouse fibroblast (NIH/3T3) cells, regarding their uptake behavior of titanium dioxide NPs. Cells were incubated with different concentrations of TiO2 NPs and samples were taken at certain time points to compare the uptake kinetics of both cell lines. Samples were analyzed with the help of flow cytometry by studying changes in the side and forward scattering signal. To additionally enable a detection via fluorescence, NPs were labeled with the fluorescent dye fluorescein isothiocyanate (FITC) and propidium iodide (PI). We found that NIH/3T3 cells take up the studied NPs more efficiently than A549 cells. These findings were supported by time-lapse microscopic imaging of the cells incubated with TiO2 NPs. Our results confirm that the uptake behavior of individual cell types has to be considered before interpreting any results of nanomaterial studies.