Photoresponsive Bio-Heterojunctions Eliciting Immunogenicity to Prevent Infection Recurrence and Accelerating Chronic Wound Regeneration.

Dynamic therapy utilizes reactive oxygen species (ROS) to antibacterial and enhance the innate immune system to treat bacterial infections. If ROS levels are too low, the elimination of pathogens and the enhancement of innate immunity cannot be achieved. However, excess accumulation of ROS may impact intracellular glutathione (GSH) levels, hindering T cell maturation and the establishment of immune memory. Herein, a multifunctional nanofiber membrane is designed, consisting of a polymer scaffold, MXene/CeO bio-heterojunctions (MX@Ce bio-HJs), and lactate oxidase (Lox) to balance the production of ROS, for the treatment of recurrent bacterial infections. In this system, MX@Ce bio-HJs upon near-infrared ray (NIR) generate photodynamic therapy, while Lox responds to the wound microenvironment exert chemodynamic therapy, synergistically produce ROS to rapidly eradicate bacteria, amplify the ability of dendritic cells to recognize and present antigens of bacterial fragments, and enhance innate immunity. Without NIR, MX@Ce bio-HJs showcase catalase-like and superoxide dismutase-like activities, scavenging subsequent ROS accumulation, promoting T cell maturation to form acquired immune memory, and combating recurrent bacterial infection. Such work highlights the potential to combat in situ bacterial infections and recurrent bacterial infections and inspires the development of future antibacterial therapies.