Biomaterials modulate macrophage polarization and inflammatory responses

It has been well established that macrophages play a key role in phagocytosis and immune defense. Macrophages can polarize into a proinflammatory M1 phenotype found in tissue defection, and an antiinflammatory M2 phenotype detected in tissue healing. Biomaterial-based modulation of macrophage polarization significantly affects inflammatory responses as well as tissue repair and regeneration owing to their effects on the morphology, migration, and differentiation of target cells. In this chapter, we overview recent advances on biomaterials with various dimensions [i.e., nanoparticles (NPs), nanofibers (NFs), and hydrogels] for modulating macrophage polarization and inflammatory responses. Relevant mechanisms involved in the interaction between biomaterials and macrophages are also briefly discussed. This chapter is expected to be useful for readers to gain knowledge on designing desired biomaterials for regulating macrophage polarization in biomedical applications.