Bioprinted dressing with symbiotic microbes for oxygen supply and antibacterial therapy for enhanced diabetic wound...

Diabetic chronic wounds exhibit delayed healing due to the high blood sugar, persistent inflammation, and bacterial infections, drawing remarkable attention worldwide. Current therapeutic approaches (e.g., surgical debridement, offloading treatment, antibiotic therapy) commonly target individual factors but fall short of modulating the complex wound microenvironment, particularly the chronic hypoxia. The symbiotic relationship between photosynthetic microorganisms and antibacterial probiotics offers a unique approach to this clinical challenge. Here, we engineer a 3D-printed bioactive microbial hydrogel (BMH) dressing by embedding Chlorella zofingiensis and Bacillus subtilis in gelatin methacryloyl as an artificial symbiotic system for modulating the diabetic wound microenvironment to promote wound healing. This BMH system demonstrates photosynthetic self‑oxygenation capability and potent antibacterial activity, thus boosting fibroblast migration and angiogenesis under hyperglycemic conditions. In diabetic rat models, BMH mitigates wound hypoxia and inflammation while enhancing vascularization and collagen deposition, thereby accelerating the healing of diabetic chronic wounds. RNA sequencing results further suggest the upregulation of genes in immune-regulation and skin-regeneration pathways. This study presents a multimodal therapeutic strategy for diabetic chronic wounds, offering insights into the design of living materials for regenerative engineering and clinical translation.