Pluronic nanoparticles do not modulate immune responses mounted by macrophages

Nanomaterials have been developed for the target delivery of medicine because they show the characteristics of selective emission or controlled release. Although accumulated data suggest the efficacy of these materials for the target delivery, it still remains to be determined whether they modulate immune responses to pathogens or foreign materials. In this study, we examined whether Pluronic nanoparticles (NPs), a type of nanomaterial, alter immune responses mediated by macrophages. When RAW 264.7 cells (RAW cells) were treated with Pluronic NPs in the presence or absence of lipopolysaccharides (LPS), they produced normal levels of nitric oxide (NO). Furthermore, the treatment with Pluronic nanomaterials did not induce cytotoxicity with or without LPS. Further, LPS-stimulated RAW cells expressed comparable levels of proinflammatory cytokine genes, such as interleukin (IL)-1 β , IL-6 and tumor necrosis factor (TNF)- α , with or without treatment by Pluronic NPs. These data suggest that Pluronic NPs do not modulate immune responses mediated by macrophages.