Screening and Characterization of the Antimicrobial Peptide IKFLRWI for the Healing of Infected Wounds.

Antimicrobial peptides (AMPs) can inhibit drug-resistant bacteria, regulate inflammation, and promote wound repair. In this study, a novel AMP, IKFLRWI, was screened by membrane-mediated capillary electrophoresis. IKFLRWI exhibited potent activity against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Candida albicans (C. albicans). It disrupts the cell wall and cell membrane permeability of pathogens with no risk of inducing bacterial resistance. IKFLRWI was loaded into an oxidized sodium alginate-gelatin (OSA-Gel) hydrogel to prepare an OSA-Gel@IKFLRWI dressing. In vivo wound experiments demonstrated that the hydrogel downregulated pro-inflammatory factors TNF-α and IL-6 and upregulated anti-inflammatory factor IL-10, repair-related factor TGF-β1, and vascular marker CD31. It alleviated local inflammation, promoted extracellular matrix synthesis and angiogenesis, and accelerated wound healing. This AMP-loaded hydrogel delivery system provides new insights for the therapy of chronic infected wounds and the translational application of AMP-based dressings.