AMP–Chitosan Coating with Bactericidal Activity in the Presence of Human Plasma Proteins

Abstract

<jats:p>Antibiotic resistance is increasing and new strategies are needed to fight infection. Advanced materials are promising tools that can be combined with innovative alternatives to conventional antibiotics to allow more targeted and efficient treatment. In this work, we explored the activity against Staphylococcus epidermidis (S. epidermidis) of the α-helical antimicrobial peptide (AMP) MSI-78(4-20) (KFLKKAKKFGKAFVKIL) when covalently bound to a chitosan coating. The AMP MSI-78(4-20) (17 mer) is an improved version of its parent MSI-78 (22 mer; commercially known as Pexiganan), a cost-effective short AMP, which was demonstrated to be as effective as MSI-78 and less toxic to eukaryotic cells. An MSI-78(4-20)–chitosan coating could be applied in several infection scenarios, ranging from bone implants to wound dressings, as chitosan possesses osteoconductive and hemostatic properties. Cysteine-modified MSI-78(4-20) was covalently immobilized onto the chitosan coating through a succinimidyl-[(N-maleimidopropionamido)-octaethyleneglycol] ester (SM(PEG)8), a heterobifuncional crosslinker, with N-hydroxysuccinimide (NHS) ester and maleimide groups, by its N- and C- termini. The MSI-78(4-20)–chitosan coating demonstrated bactericidal properties independently of the tethering site and an improved performance in the presence of plasma proteins, which mimics conditions that will be encountered in vivo. This AMP–chitosan coating has therefore great potential for applications in medical devices such as implants or even wound dressings.</jats:p>

On the Applicability of Chitosan Oligomers-Amino Acid Conjugate Complexes as Eco-Friendly Fungicides against Grapevine Trunk Pathogens

“…In connection with polysaccharide-amino acid conjugates, several examples for medical applications have been recently reported [34][35][36], but applications in the field of agronomy are still at a very early stage of development. To the best of the authors' knowledge, there is only one recent study on chitosan oligomers-amino acid conjugates against Fusarium culmorum (Wm.G.…”

Antimicrobial coatings based on chitosan to prevent implant-associated infections: A systematic review

“… ( López et al, 2019 ) α-helical AMP MSI-78(4-20) (KFLKKAKKFGKAFVKIL) Gold substrates b Bone implants and other medical devices S. epidermidis f The AMP-chitosan coating did not significantly reduce bacterial adhesion but decreased the viability of adhered cells by 60%. ( Monteiro et al., 2020 ) n.d., not described. a in vivo study.…”

An Update on Antimicrobial Peptides (AMPs) and Their Delivery Strategies for Wound Infections

“…In another study, cysteine-modified MSI-78 AMP was covalently immobilized to chitosan coatings through a PEG linker. MSI-78-chitosan films showed high antimicrobial efficacy against S. epidermidis in both PBS and PBS supplemented with 1% human plasma, maintaining significantly low bacterial adhesion, while killing 76% of adherent bacteria [114]. This type of coating could be successfully used for medical applications for implants or wound dressings.…”