Abstract
Aim: Alumina nanoparticles (AlNPs) exert toxic effects in several organs. This study aimed to investigate the toxicity of AlNPs to the immune system. Materials & methods: AlNPs distribution was assessed using CRi in vivo fluorescence imaging. Inductively coupled plasma atomic emission spectrometry was used to detect the content of aluminum in the spleen. Cytokines expression was detected in the immune organs and blood of mice. Results & conclusion: AlNPs can accumulate in mice spleen. Superoxide dismutase and glutathione levels decreased, whereas the level of malondialdehyde increased with decreasing particle size. AlNPs exposure caused cytokine level changes in the spleen, thymus and serum, besides causing damage to immune organs and dysfunction of immune cells, leading to abnormal immune-related cytokine expression.
Graphical abstract
AlNPs can be exposed to mice in vivo, and can accumulate in the immune organs of mice, causing oxidative damage to the immune organs and immune cell dysfunction, ultimately leading to the abnormal expression of immune-related cytokines, resulting in toxic effects on the immune system of mice.

Papers of special note have been highlighted as: • of interest; •• of considerable interest
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