Effects of nanoparticle physicochemical properties on macrophage polarization

Tumor-associated macrophages (TAMs) are crucial in regulating tumor immune microenvironment (TIME), tumor development and tumor therapy. Nanoparticles, as traditional tumor targeting drug delivery systems, of which the intrinsic immunomodulatory potential has been gradually explored by modulating physicochemical properties. This review systematically summarizes advancements in polarizing macrophages by regulating physicochemical properties of nanoparticles including size, morphology, surface properties, stiffness, and other factors. Furthermore, the polarization mechanisms are expounded via biochemical and mechanical signaling pathways. Size of nanoparticles affects macrophage polarization through lysosomal stress and membrane interaction; morphology of nanoparticles impacts macrophage polarization through inducing membrane curvature or modulating cellular metabolism; surface properties of nanoparticles effects macrophage polarization through enhancing nanoparticle binding ability to cell membrane; stiffness of nanoparticles polarize macrophages through activating mechanosensitive ion channels and inducing deformation of membrane; other properties of nanoparticles effects macrophage polarization via glycolysis, oxidative phosphorylation, etc. These outcomes contribute to the optimization of nanomedicine physicochemical properties for tumor immunotherapy by regulating polarization of TAMs and reshaping the immunosuppressive TIME, thereby driving the development of precision immuno-oncology for various malignancies.