ECOSPHERE, Department of Biology, University of Antwerp, Groenenborgerlaan 171, Antwerp 2020, Belgium; Blue Growth Research Lab, Ghent University, Wetenschapspark 1, Ostend 8400, Belgium.
Blue Growth Research Lab, Ghent University, Wetenschapspark 1, Ostend 8400, Belgium.
Ecotoxicol Environ Saf. 2024 Nov 1;286:117255. doi: 10.1016/j.ecoenv.2024.117255. Epub 2024 Oct 26.
Bivalve hemocytes, particularly granulocytes and hyalinocytes, play a crucial role in cell-mediated immunity. However, their interactions with aged plastic particles, exhibiting altered properties that more closely resemble those in natural environments, remain largely underexplored. This study assesses the differential responses of hemocyte subpopulations (Mytilus edulis) to chemically aged polyethylene terephthalate (PET) microplastic (MPs) and nanoplastic (NPs) particles across multiple cellular effect endpoints. Particle characteristics were analyzed using Single Particle Extinction and Scattering, Raman Spectroscopy, Scanning Electron Microscopy, and Dynamic Light Scattering. In vitro experiments with aged PET MPs (1.9 µm) and NPs (0.68 µm) were conducted at three internally relevant concentrations: 10 (C1), 10³ (C2), and 10⁵ particles/mL (C3). Cellular responses were assessed by measuring lysosomal content stability, reactive oxygen species (ROS) production, cellular mortality, and morphological parameters using flow cytometry at 6, 12, 24, and 48 hours. Our findings provide mechanistic insights into the differential sensitivities of granulocytes and hyalinocytes to aged PET, influenced by particle size and concentration. Specifically, aged PET MPs and NPs induce distinct size and concentration-dependent patterns of lysosomal destabilization, coinciding with the loss of functional integrity. Elevated ROS levels were observed only in granulocytes and hyalinocytes exposed to high concentrations of aged PET NPs, underscoring the effects on oxidative stress. Both aged PET MPs and NPs induce significant increases in cellular mortality, particularly after 24 h of exposure at high concentrations. These findings reveal the complex cellular mechanisms underlying hemocyte functional impairment following exposure to aged PET particles under environmentally and biologically relevant conditions.
双壳类血细胞，特别是粒细胞和透明细胞，在细胞介导的免疫中起着至关重要的作用。然而，它们与老化的塑料颗粒之间的相互作用，这些颗粒表现出更接近自然环境中特性的改变，在很大程度上仍未得到充分探索。本研究评估了血细胞亚群（贻贝）对化学老化聚对苯二甲酸乙二醇酯（PET）微塑料（MPs）和纳米塑料（NPs）颗粒的不同反应，涉及多个细胞效应终点。使用单颗粒消光和散射、拉曼光谱、扫描电子显微镜和动态光散射分析了颗粒特性。在三个内部相关浓度（10（C1）、10³（C2）和 10⁵个颗粒/mL（C3））下进行了具有老化 PET MPs（1.9 µm）和 NPs（0.68 µm）的体外实验。通过流式细胞术在 6、12、24 和 48 小时测量溶酶体含量稳定性、活性氧（ROS）产生、细胞死亡率和形态参数，评估细胞反应。我们的研究结果提供了有关颗粒大小和浓度对老化 PET 影响下粒细胞和透明细胞敏感性差异的机制见解。具体而言，老化 PET MPs 和 NPs 诱导了溶酶体不稳定的不同大小和浓度依赖性模式，这与功能完整性的丧失相一致。仅在暴露于高浓度老化 PET NPs 的粒细胞和透明细胞中观察到 ROS 水平升高，强调了对氧化应激的影响。老化的 PET MPs 和 NPs 都会导致细胞死亡率显著增加，尤其是在高浓度暴露 24 小时后。这些发现揭示了在环境和生物相关条件下，暴露于老化 PET 颗粒后血细胞功能障碍的复杂细胞机制。
