Immunomodulatory gallium/glycyrrhizic acid hydrogels for treating multidrug-resistant Pseudomonas aeruginosa-infected pressure ulcers

Current approaches to treating infected pressure ulcers (IPUs) tend to lack specificity. Such injuries frequently exhibit extended inflammation and slow tissue regeneration, largely due to a surplus of M1 macrophages in the impacted regions. While immunomodulatory hydrogels offer potential for targeted IPU care, facilitating a safe and efficient shift from M1 to M2 macrophages continues to be a considerable challenge. The wound's harsh microenvironment—marked by unchecked infections and reactive oxygen species—often undermines the effectiveness of these hydrogels. We unveil a custom-engineered hydrogel dressing specifically designed to have immunomodulatory properties for expediting the healing of IPUs. Consisting of intertwined polymer networks, this hydrogel incorporates gallium (Ga) ions-triggered self-assembled glycyrrhizic acid (GA). Crucially, both in vitro and in vivo examinations, along with RNA sequencing assessments, demonstrate that the Ga/GA combination successfully reduces the M1/M2 macrophage ratio under inflamed circumstances, thereby contributing to improved IPU wound recovery. In summary, our proposed immunomodulatory strategy provides a simple, secure, and highly efficacious method for managing IPUs.