M1 type macrophage targeted anti-inflammatory exosomes derived from BMSC for the treatment of acute and chronic inflammatory diseases

Uncontrolled inflammatory response is both an intervention target for various diseases, and the design basis for drug delivery strategies. In this work, based on the highly enriched characteristics of M1 type macrophages in local inflammation, we used exosomes derived from bone marrow mesenchymal stem cells (BMSC) as drug carriers, modified with hyaluronic acid (HA) and polyethylene glycol (PEG) to prepare an inflammation targeted and anti-inflammatory treatment nanoplatform (EXs-PH). By targeting M1 macrophages, HA endows EXs-PH with the ability to target inflammation, while PEG reduces the interaction between plasma proteins and exosome membrane proteins, giving the exosomes the ability to circulate within the body for a long time. The results indicate that after HA and PEG (PH) modification, exosomes derived from BMSC (EXs) can effectively enrich in the inflammatory site, achieving precise administration of curcumin (Cur) with anti-inflammatory and repair promoting functions. In vivo experiments on acute and chronic inflammatory models of spinal cord injury (SCI) and rheumatoid arthritis (RA) also showed that PH modified Exs loaded with Cur (Cur@EXs-PH) were more effective in improving the recovery of motor function after lesions. In conclusion, the engineered Cur@EXs-PH we designed, provides a new drug delivery carrier for treating inflammatory diseases.