A side-effect-free chemotactic-antibacterial wound dressing for programmatic trapping, killing of bacteria, and wound...

Wound infection is a common clinical complication in surgery and war trauma, which can trigger an adverse pathological state of local and systemic inflammatory response. Although antibiotics were once regarded as an important means to suppress wound infections, their frequent use can lead to bacterial resistance and delay tissue healing and regeneration. In order to solve these problems, based on previous research, we screened and designed a chemotactic, antibacterial dressing that promotes wound healing. First, an arginine-glycine-aspartate tripeptide (RGD) with a significant chemotactic effect on Escherichia coli was systematically screened through chemotactic experiments in vitro. The RGD was grafted to gelatin methacrylated (GelMA), which was then combined with carboxymethyl chitosan (CMCS)-wrapped silver nanoparticles to form a composite hydrogel. Finally, transplanting the composite hydrogel into infected wound models in mice and rabbits can directionally attract bacteria, maintain the long-term bactericidal ability of silver ions, and promote wound healing. Pathway enrichment analysis showed that RGD significantly improved the mobility of Escherichia coli by activating the chemotaxis pathways. The hydrogel transplanted onto the wound surface further inhibits inflammatory signaling pathways such as NF-κB through antibacterial activity, thereby providing a basis for wound regeneration (significant activation of Wnt and ECM pathways). These results indicate that the chemotactic-antibacterial wound dressing provides a novel, side-effect-free treatment method, that provides an optimal wound microenvironment for promoting wound healing. This provides a new strategy for the treatment of clinically infected wounds.