Car-Macrophage Therapy For Radiation-Induced Oral Mucositis

This study investigates whether chimeric antigen receptor (CAR)-macrophage therapy, delivered via exosome-liposome hybrid vesicles, can enhance the clearance of immunogenic dead cells and accelerate mucosal healing in radiation-induced oral mucositis (RIOM). Female C57BL/6 mice (5–6 weeks old) were used to establish an RIOM model, and radiation-exposed cells were analyzed for calreticulin (CRT) translocation via immunofluorescence, flow cytometry, and immunohistochemistry. Hybrid vesicles, composed of human umbilical cord mesenchymal stem cell (hUC-MSC) exosomes (EXO) and liposomes, were engineered to deliver CRT-targeting pDNA for macrophage reprogramming. In vitro efficacy was assessed using flow cytometry, Western blot, transcriptomics analysis. Reactive oxygen species (ROS)-responsive microneedles were employed as a delivery system for hybrid vesicles in vivo, and their effectiveness was evaluated through fluorescence imaging and histological staining. All animal experiments were approved by the institutional ethics committee. The hypothesis validation phase concluded two weeks post-radiation, while the therapeutic evaluation phase lasted three months post-radiation. CRT translocation and immunogenic cell death were confirmed post-radiation. CAR-macrophages exhibited enhanced efferocytosis, leading to increased clearance of apoptotic cells and improved tissue remodeling. In vivo, CAR@EXO therapy significantly accelerated mucosal regeneration, restored epithelial integrity, and reduced fibrosis, demonstrating its potential as a targeted macrophage-based intervention. CAR-macrophage therapy, facilitated by hybrid vesicle-mediated pDNA delivery, effectively reprograms macrophages, enhances apoptotic cell clearance, and promotes mucosal healing in RIOM. This strategy represents a novel macrophage-targeted immunotherapy for radiation-induced tissue damage.