Abstract：
The widespread use of microplastics and their harmful effects on the environment have emerged as serious concerns. However, the effect of microplastics on the immune system of mammals, particularly their offspring, has received little attention. In this study, polystyrene microplastics (PS-MPs) were orally administered to male mice during lactation. Flow cytometry was used to assess the immune cells in the spleens of both adult male mice and their offspring. The results showed that mice exposed to PS-MPs exhibited an increase in spleen weight and an elevated number of B and regulatory T cells (Tregs), irrespective of dosage. Furthermore, the F1 male offspring of the PS-MPs-exposed group had enlarged spleens; an increased number of B cells, T helper cells (Th cells), and Tregs; and an elevated ratio of T helper cells 17 (Th17 cells) to Tregs and T helper cells 1 (Th1 cells) to T helper cells 2 (Th2 cells). These results suggested a pro-inflammatory state in the spleen. In contrast, in the F1 female offspring exposed to PS-MPs, the changes in splenic immune cells were less pronounced. In the F2 generation of mice with exposed to PS-MPs, minimal alterations were observed in spleen immune cells and morphology. In conclusion, our study demonstrated that exposure to real human doses of PS-MPs during lactation in male mice altered the immune status, which can be passed on to F1 offspring but is not inherited across generations.
摘要：
微塑料的广泛使用及其对环境的有害影响已成为严重关切。然而,微塑料对哺乳动物免疫系统的影响，尤其是他们的后代，很少受到关注。在这项研究中,在泌乳期间向雄性小鼠口服施用聚苯乙烯微塑料(PS-MPs)。流式细胞术用于评估成年雄性小鼠及其后代脾脏中的免疫细胞。结果表明，暴露于PS-MPs的小鼠脾脏重量增加，B和调节性T细胞（Tregs）数量增加，无论剂量。此外，PS-MPs暴露组的F1雄性后代脾脏增大；B细胞数量增加，T辅助细胞（Th细胞），和Tregs;以及T辅助细胞17(Th17细胞)与Tregs和T辅助细胞1(Th1细胞)与T辅助细胞2(Th2细胞)的比率升高。这些结果提示脾脏中的促炎状态。相比之下,在接触PS-MP的F1雌性后代中，脾免疫细胞的变化不太明显。在暴露于PS-MPs的F2代小鼠中，在脾免疫细胞和形态学中观察到最小的改变。总之,我们的研究表明，在雄性小鼠泌乳期间暴露于真实人类剂量的PS-MPs改变了免疫状态，可以传给F1后代，但不能代代相传。
