Single nucleus (sn) RNA sequencing analysis of murine liver cells after 12 weeks of weekly treatment with either PBS, 50nm polystyrene or 500nm polystyrene

Once ingested, nano- and microplastic particles (MNPs) can translocate from the gut into internal organs, likely via circulation. In humans, MNPs have been detected in macrophages within carotid artery plaques, suggesting that these highly phagocytic cells, may also serve as key targets for MNPs under homeostatic conditions.

Kupffer cells (KCs), the liver-resident macrophages, play a crucial role in liver homeostasis by regulating metabolism, clearing opsonized target cells, and serving as the first line of defence against bacteria. Residing within the liver sinusoids, they continuously monitor the bloodstream, efficiently capturing and eliminating pathogens and circulating particles to maintain immune and metabolic balance5. It remains unknown whether KCs efficiently capture and store MNPs and how this might affect liver function.