The effects of nanoplastics on macrophages unraveled by Synchrotron high-resolution spectro-microscopies


Nanoplastics (NPs) can easily interact with cells, therefore their presence in the environment poses a significant concern for human health. However, mechanisms of toxicity are still unknown, and only a few studies focused on model NPs–immune system interaction.

a) Fluorescence image of a M1 macrophage exposed to model polypropylene NPs labelled with cadmium selenide quantum dots (CdSe-QDs; b) Selenium (L Line) chemical map of the same cell of panel a; c) absorption image of the cell acquired with 300 nm spatial resolution.

The CERIC PhD fellow Federica Zingaro, Dr. Alessandra Gianoncelli and Dr. Giovanni Birarda (Elettra Sincrotrone Trieste), Dr. Lorella Pascolo  (IRCCS Burlo Garofolo Hospital for Mothers and Children, Trieste), and colleagues focused on the possible effects of NPs on macrophages, an important class of phagocytotic innate immune cells which are involved in several physiological and pathological processes, such as inflammation and infection (with particular regard to M1 phenotype, which plays an important role in primary immune response against exogenous agents). To study in vitro M1 phenotype macrophages, scientists exploited a combination of techniques available at the CERIC Italian partner facility at Elettra Sincrotrone Trieste, including Scanning transmission X-ray microscopy (STXM) and low-energy X-ray fluorescence (LEXRF), both performed at the TwinMic beamline, and Fourier Transform Infrared (FTIR) spectro-microscopy measurements, carried out at the Chemical and Life Science branch of the SISSI-Bio beamline. Researchers could then demonstrate that M1 phenotype macrophages undergo substantial alterations both in morphology and lipids metabolism when exposed to polypropylene and polyvinyl chloride NPs at the appropriate experimental concentrations and incubation time.

Although experimental data do not show any alteration of cell viability, these outcomes prove that nanoplastics can cause an evident impairment in lipids metabolism of immune system cells, a hallmark of activation of phagocytosis and oxidative stress.


Morphological and lipid metabolism alterations in macrophages exposed to model environmental nanoplastics traced by high-resolution synchrotron techniques
Zingaro F., Gianoncelli A., Ceccone G., Birarda G., Cassano D., La Spina R., Agostinis C., Bonanni V., Ricci G., Pascolo L., Frontiers in Immunology, 2023