@article {19109, title = {New antibacterial spider silk coatings to prevent bacteria adherence to surgical sutures}, booktitle = {Chem2Nature Second School}, year = {2017}, month = {2017-06-08 00:00:00}, address = {Porto}, abstract = {

Biomaterial-associated infections often occurring after extensive surgery, and are one of the main causes of patient mortality and morbidity. Despite improvements in biomedical field, microbial pathogens proliferation on medical devices are still an emanate problem. Therefore, it is important to develop new biomaterials with intrinsic antimicrobial properties, aiming to reduce the risk of microbial infections. Spider silk is considered an outstanding biomaterial due to the combination of high strength, toughness and excellent elasticity. Through recombinant DNA technology, we can engineer new spider silk-based biomaterials by adding different functional protein domains. For instance, spider silk-based biomaterials functionalized with antimicrobial peptides (AMP) have demonstrated biological biocompatibility and antimicrobial properties.

Herein, we aim to explore the use of spider silk proteins functionalized with AMP as new antibacterial coatings for commercial silk sutures (Perma-Hand{\textregistered}). To achieve this purpose, Perma-Hand{\textregistered} sutures were coated with spider silk protein functionalized with AMP (6mer-HNP1) and with spider silk protein without AMP (6mer). The biological and antibacterial potential of the new Perma-Hand{\textregistered} coated sutures were assessed. Perma-Hand{\textregistered} suture without coating and a suture with antibacterial properties (VicrylPlus{\textregistered}) were used as controls.

Perma-Hand{\textregistered} sutures coated with 6mer-HNP1 exhibited a lower adherence of Methicillin resistant Staphylococcus aureus (MRSA) when compared to Perma-Hand{\textregistered} sutures coated with 6mer or uncoated ones. Perma-Hand{\textregistered} sutures coated with 6mer-HNP1 also showed a similar antibacterial activity when compared to VicrylPlus{\textregistered}. The formation of bacterial biofilm after 24h growth was only visible in the Perma-Hand{\textregistered} sutures coated with 6mer and uncoated ones, demonstrating the antibacterial potential of these sutures coated with 6mer-HNP1. The hemolytic activity of the Perma-Hand{\textregistered} sutures coated with 6mer-HNP1 and 6mer was also evaluated and no negative effect was observed, further evidencing to the biocompatibility of the bioengineered spider silk proteins. In vitro cell studies using human lung fibroblasts cell line (MRC5) showed a nontoxic and cytocompatible behavior of the Perma-Hand{\textregistered} sutures coated with 6mer-HNP1 or 6mer. The outcomes of this study suggest that the functionalization of spider silk proteins with AMP could pose as a new strategy to develop antibacterial coatings capable of preventing microbial proliferation associated to infections problems on biomaterials.

Acknowledgements.\ The autor aknwolegdes the Project Project UID/Multi/50026/2013\  (POCI-01-0145-FEDER-007038),\ ARF would like to thank the Post-Doctoral grant SFRH/BPD/100760/2014.\ 

}, keywords = {Antimicrobial peptides, Spider silk, sutures}, author = {Franco, A. R. and Leonor, I. B. and Kaplan, D. L. and Reis, R. L.} }