EngineeredHouttuynia cordata-derived exosome-like nanoparticles as a dual-targeting platform for eradicating intracellular methicillin-resistantStaphylococcus aureus.

Intracellular infections caused by methicillin-resistant Staphylococcus aureus (MRSA) present a significant therapeutic challenge due to the limited access of conventional antibiotics to bacterial reservoirs within macrophages. To address this, we developed a dual-targeting delivery system using Houttuynia cordata-derived exosome-like nanoparticles (HELNs) functionalized with mannose and vancomycin for rifampicin (Rif) encapsulation (Rif@HELNs-MV). The engineered nanoparticles were designed to sequentially target macrophages through mannose receptor-mediated endocytosis and subsequently bind to intracellular MRSA via vancomycin-peptidoglycan interactions. Systematic characterization revealed that Rif@HELNs-MV maintained structural integrity with a spherical morphology, high Rif loading capacity (18.3 ± 2.1 %). Cellular assays demonstrated enhanced uptake and precise targeting to intracellular MRSA. The formulation showed superior antibacterial efficacy in murine models of peritonitis and muscle infection, significantly reducing bacterial loads while exhibiting excellent biocompatibility. This dual-targeting strategy represents a promising approach for treating persistent intracellular infections by overcoming the physiological barriers that limit conventional antibiotic therapies.