Immunomodulation of nanoparticles: Unveiling immunosuppressive and anti- inflammatory properties

Interactions between nanoparticles and eukaryotic cells are nearly inevitable once they gain entry into the cell. Such accidental interactions between immune cells and nanoparticles may trigger a destructive chemical response and increase the risk for autoimmune diseases, tumors, and infections. Nanoparticles can also interface with biologic systems and elicit allergic or inflammatory responses, thereby activating the complement system. Nanoparticles have been known to stimulate the immune system either as haptens or adjuvants. The effects have also been known to be immunosuppressive. This review article summarizes some of the in vivo and in vitro studies carried out to show how nanoparticles stimulate or suppress the immune system in animals. Further research should, therefore, focus on the impact that the physical and chemical properties of nanoparticles have on their performance within the biological system to ensure safe usage of the particles. These qualities may interrupt the experimental process and have a greater influence on the interaction between nanoparticles and immune systems.