Neutrophil membrane-derived nanoparticle loading TLR7 agonists augments radiotherapy efficacy and boosts abscopal effect via regulating tumor microenvironment

Abstract Background Increasing evidence indicates that radiotherapy (RT) has synergistic inhibitory efficiency with immunotherapy agents in multiple cancers and enhances abscopal effects by regulating the innate immune response, which was further investigated this study. Neutrophils are recruited radiated tumors. Therefore, neutrophil membrane-coated nanoparticles potentially deliver R837 (Toll-like receptor 7 agonist) to Methods A novel nanoparticle R837@PLGA@Neu prepared initially assembling PLGA (poly (lactic- co -glycolic acid)) (TLR7 into R837@PLGA followed coating membrane. Characterizations of were performed. Tumor targeting evaluated vivo fluorescent imaging CT26-bearing mice. Treatments combined RT carried out unilateral bilateral CRC tumor-bearing mice, validations cells tumors flow cytometry. Results The characteristics well identified, it confirmed have high uptake ability low cytotoxicity colorectal cancer (CRC) vitro, as its strong tumor-targeting exciting findings exerted prominent tumor inhibition not only tumors, but also distant without RT, suggesting enhancement efficacy effect RT. possible underlying mechanisms remodeling microenvironment triggering mature dendritic CD8 + T cells. Conclusion In summary, our suggested membrane-derived showed efficiency, combination had a promising mice via cell regulation. Our results provide probable strategy for treatment.