Nanofibrous dressings incorporating a synergistic antibacterial-anti-inflammatory effect for infected wound healing
Wei Xu, Tingting Xu, Lei Yu, Xuchao Ning, Chunling Zhang, Bingcheng Yi, Wufei Dai, Zhihua Zhu, Haiguang Zhao
Abstract
Bacterial infections and chronic inflammation disrupt wound immune homeostasis and impair healing progression. Herein, we report a novel nanofibrous dressings that exhibits a synergistic antibacterial-anti-inflammatory effect through the integration of the physical barrier properties of electrospun nanofibers, the antimicrobial activity of biomacromolecule polylysine (PLys), and the anti-inflammatory and antioxidant effects of natural macromolecule tannic acid (TA). Using poly(L-lactide-co-ε-caprolactone) (PLCL) as the base biomaterial, sequential surface modification with TA and PLys enhanced wettability and introduced a positive surface charge, yielding a dressing with exceptional cytocompatibility and potent antimicrobial activity against Staphylococcus aureus. In vitro studies revealed that the PLys-grafted, mussel-inspired nanofibers (PLys@TA@PLCL) modulated the wound microenvironment by suppressing fibroblast-to-myofibroblast differentiation, mitigating pro-inflammatory responses, and accelerating extracellular matrix (ECM) deposition and remodeling. In vivo evaluations demonstrated that PLys@TA@PLCL nanofibers effectively reduced bacterial burden and prevented yellow scab formation, while accelerating healing of infected wounds. Notably, these dressings exhibited robust anti-inflammatory activity during early stages of repair and promoted near-complete wound closure by 2 weeks, accompanied by enhanced collagen synthesis, skin regeneration, and hair follicle neogenesis. Collectively, these findings highlight the therapeutic potential of PLys@TA-modified nanofibrous dressings for managing chronic, full-thickness wounds.