Nanoplastic effects on human vascular endothelial cells: A comparison of primary cells (HUVEC) and immortalized cells (hy926) after exposure to polystyrene nanoplastics

Humans are being exposed to nanoplastics primarily through inhalation and ingestion. Once in the thoracic or digestive tract, the nanoplastics come in contact with the epithelial cell layer. This layer has been known to uptake nanoplastics leading to oxidative stress and ROS generation. The next cell layer beneath the epithelial layer is the capillary endothelium. There is currently very little information known about what happens once the endothelial layer is exposed to nanoplastics. Research on endothelial stress response has involved two types of cell lines, primary and immortalized cell lines. The primary cell line comes directly from human/animal tissues, Human Umbilical Vein Endothelial Cells (HUVEC), while the immortalized cell line is a fusion of two cell types that is a functional equivalent of the endothelial layer (hy926 cells). I found that both endothelial cell models were found to uptake polystyrene nanoplastics and both were similar in their responses to polystyrene nanoplastics. Both cell lines showed no significant difference in the amount of Caspase‐3 activity, mitochondrial degradation, or Reactive Oxygen Species (ROS) generation when exposed to 10, 20, and 40 μg/ml of polystyrene nanoplastics compared to controls. Our data suggest that at these polystyrene concentrations, either model system can be used as an accurate model for measuring endothelial cell layer responses to nanoplastics.