Antibacterial and angiogenic wound dressings for chronic persistent skin injury

Abstract Antibacterial and angiogenic wound dressings are highly desirable for chronic persistent skin injuries complicated by bacterial infection or diabetes. Herein, a series of quaternized chitin (QC) and fibroblast growth factor 2-hyaluronic acid (FGF2-HA)-modified poly(lactic-coglycolic acid) (PLGA) nanofiber dressings were successfully fabricated using layer-by-layer (LBL) self-assembly technology. The physicochemical and biological properties of the obtained dressings (named PQHF-n, with n = 0, 2, 6, or 10 corresponding to the number of QC layers) were investigated. PQHF-n showed broad-spectrum antibacterial activity against drug-resistant bacteria (MRSA), gram-positive bacteria (S. aureus) and gram-negative bacteria (E. coli). Additionally, PQHF-n exhibited good biocompatibility and bioactivity towards fibroblasts and human blood. PQHF-10 could promote the proliferation and migration of L929 cells by activating the cell cycle and epithelial-mesenchymal transformation (EMT) pathways. The in vivo application potential of PQHF-n was investigated using a MRSA-infected wound model. The results revealed that PQHF-10 could facilitate wound healing within 15 days mainly through reducing inflammation, enhancing collagen deposition, and promoting proliferation and vascularization. In conclusion, this work provided a multifunctional wound dressing material with potential for application in complex clinical practice.