Platelet Membrane Vesicle-Integrated Gelatin Scaffold as a Biomimetic Artificial Scab for Oral Ulcer Healing

Abstract

Wound healing in the oral cavity remains clinically challenging because of the constantly moist, mechanically active, and bacteria-rich environment, where conventional dressings often fail to provide sustained protection or active regenerative support. Inspired by the physiological functions of natural scabs, we developed a biomimetic artificial scab by integrating platelet membrane vesicles (PMVs) into a chemically crosslinked absorbable gelatin scaffold (PMVs-AGS). The resulting construct combines mechanical protection, hemostatic capability, and bioactive signaling in a single, cell-free platform. PMVs-AGS exhibited high water absorption, strong mucosal adhesion, and a biphasic release profile of PMVs. In vitro assays demonstrated rapid erythrocyte and platelet aggregation, good cytocompatibility, and enhanced proliferation and migration of fibroblasts and macrophages. In a rat oral ulcer model, PMVs-AGS significantly accelerated wound closure, promoted epithelial regeneration and organized collagen deposition, reduced inflammatory infiltration, and improved functional recovery compared with controls. Overall, this biomimetic artificial scab effectively recapitulates key structural and biological features of natural scabs, offering a practical and scalable strategy for oral mucosal wound repair and potentially other difficult-to-heal wounds.