Our results indicate that EGF enhances the uptake efficiency of PS NPs by clathrin-mediated endocytosis, inducing the aggregation of EGF receptors on the cell membrane surface.
These results could be important for developing safe NPs and their safe use in medical applications.
The aim of this study was to clarify the effects of epidermal growth factor (EGF) on the uptake efficiency of polystyrene nanoparticles (PS NPs) by A431 cells, a human carcinoma epithelial cell line.
The results showed that EGF enhanced the uptake efficiency of A431 cells for PS NPs.
The harvested cells were treated with trypsin/EDTA for 12 min, centrifuged at 1200 rpm for 3 min, and then the cell debris was suspended in 1 m L PBS 1×.
Polystyrene nanoparticles (PS NPs) are widely used as a model for studying the interaction between NPs and cells due to their many advantages, including commercial availability, high quality, diverse sizes and shapes, biocompatibility, biological non-toxicity, and high functionality due to the presence of many chemical groups [1,2,3].The cells were then incubated overnight at 4 °C with fluorescently labeled anti-EGFR antibody (Abcam, London, UK).Nuclear DNA was labeled with DAPI (4′,6-diamidino-2-phenylindole) (Thermo Fisher Scientific, Waltham, MA, USA) and images were obtained with a confocal laser-scanning microscope (LSM510 META, Carl Zeiss Inc., Jena, Germany).Cells untreated with either NPs or EGF were used as control.The cells were washed twice with phosphate buffered saline (PBS) 1× to completely remove excess NPs.
Indeed, PS NPs have been reported to internalize in many types of cells, such as hepatocyte , macrophage , lung , and epithelium .