The effect of immuno-instructive polymers on human neutrophil attachment and activation

Abstract

Implantation of a biomaterial into the human body elicits an inflammatory response which can ultimately lead to implant rejection. Neutrophils central to that inflammatory response, activating a cascade of proteins and releasing hydrolytic enzymes. This cascade of events will recruit more neutrophils and other immune cells (such as monocytes and macrophages) to the site of the implanted biomaterial, which plays an essential role in regulating wound healing mechanisms. Therefore, this study aimed to investigate whether polymer coatings can modulate the attachment and activation of neutrophils. Human primary neutrophils isolated from peripheral blood were cultured on the surface of five selected polymers of interest. Experiments were carried out to assess the viability and quantify the activation of neutrophils by staining with surface marker labelled antibodies. Results indicate that neutrophils cultured on the DMEMAm polymer show good viability and attachment compared to those cultured on the HEMA polymer, a known low attachment polymer. In terms of modulating neutrophil activation of neutrophils, this data shows that there was no activation of neutrophils on the DMEMAm polymer measured with CD66b and CD177 surface markers. However, with CD63 surface marker, there was upregulation. In conclusion, these data suggest that the DMEMAm polymer supports the authors’ hypothesis by modulating the activation and adherence of neutrophils. This could have implications for designing polymers as a coating on medical devices.