Dual-functional gallium/chitosan/silk/umbilical cord mesenchymal stem cell exosome sponge scaffold for diabetic wound...

The treatment of diabetic wounds possessed significant challenges in clinical practice, which was accompanied with continuous infection, inflammation, and limited angiogenesis. Current wound dressings used for diabetic wound healing struggle to address these issues simultaneously. Therefore, Ga³⁺ was added to the chitosan/silk solution to confer potent antibacterial properties. Subsequently, umbilical cord mesenchymal stem cell exosomes (UCSC-Exo) were integrated into the gallium/chitosan/silk solution to enhance its angiogenesis-inducing activity. The mixture was lyophilized to prepare gallium/chitosan/silk/exosome sponge scaffolds (Ga/CSSF-Exo sponge scaffolds). The experiments of In vitro and in vivo demonstrated that Ga/CSSF-Exo sponge scaffolds exhibited sustained release of Ga³⁺ and bioactive exosomes, which effectively exerted continuous antibacterial effects and promoted angiogenesis. In diabetic rat wound models, Ga/CSSF-Exo sponge scaffolds facilitated angiogenesis, suppressed bacterial growth and inflammation, as well as promoted collagen deposition and re-epithelialization of wounds. Collectively, our findings suggested that Ga/CSSF-Exo held excellent potential for diabetic wound healing.