Dal-Engineered Nanoplatform For Infected Bone Regeneration

This study aims to develop a DNA Aptamer lock (DAL)-engineered neutrophil membrane (NM)-encapsulated nanoplatforms (DALenm) for targeted delivery of PFKL agonist (NA-11) to treat infected mandibular bone defects. 1. DAL Design and Nanoparticle Fabrication: DAL was synthesized and conjugated to PLGA nanoparticles loaded with NA-11. The DAL-NM-NA-11 complex (DALenm) was prepared via co-encapsulation and extrusion techniques. 2. Characterization: The profile and targeting performance of DALenm were analyzed using TEM, DLS, UV-Vis spectroscopy, Western blot, and fluorescent staining. 3. In Vitro Studies: • Immune Function Conversion: NETosis key markers and bacterial phagocytosis were evaluated using flow cytometry and bacterial viability assays. • Biological Neutralization: LPS neutralization and cytokine binding were assessed via RT-qPCR and ELISA. 4. In Vivo Studies: A mouse model of infected mandibular bone defect was established by inoculating S. aureus. DALenm efficacy was evaluated via micro-CT, histology, and immunohistochemistry at multiple time points. 1. In Vitro: DALenm efficiently targeted activated neutrophils, reduced ROS production and enhanced bacterial phagocytosis of neutrophils compared to control groups. 2. In Vivo: DALenm treatment significantly improves mandibular bone regeneration, reduces bacterial load, and modulates the inflammatory microenvironment. The DNA Aptamer lock (DAL)-modified DALenm nanoplatform, leveraging the targeted delivery properties, exhibits dual functionality in simultaneously neutralizing pathogenic mediators and promoting neutrophil phagocytosis through PFKL-mediated metabolic reprogramming, offering a promising therapeutic strategy for infected mandibular bone defects.