Macrophage-targeting bioactive glass nanoparticles for the treatment of intracellular infection and subcutaneous abscess

Staphylococcus aureus (S. aureus) can survive phagocytosis and gain shelter from macrophages in some cases, and the clinical treatment of the intracellular bacterium also encounters the difficulty of traditional antibiotics in entering mammalian cells. In this work, we use mannose-modified bioactive glass nanoparticles decorated with silver nanoparticles (BGNs-Man/Ag) to treat the S. aureus-induced intracellular infection of macrophages. The results showed that BGNs-Man/Ag could target macrophages, elevate the intracellular ROS levels and drive them toward the M1 phenotype, which was crucial to activate the cell autonomous defence in disposing the intracellular infection. Attractively, BGNs-Man/Ag exhibited higher intracellular bacterial killing efficiency than free vancomycin. For the in vivo treatment of subcutaneous abscess, BGNs-Man/Ag significantly increased the population of M1 macrophages at the early stages of the infection site, resulting in enhanced bactericidal activity and improved regeneration of skin tissues. In short, BGNs-Man/Ag can be a promising antibacterial material in treating the S. aureus-induced intracellular infection of macrophages and subcutaneous abscesses.