二氧化钛纳米颗粒对小鼠单核巨噬细胞超微结构影响的电镜研究

Electron micnoscopic study of ultrastructural effect of nano-TiO_2 on mouse monocyte-macrophage

目的:应用电镜观察二氧化钛纳米颗粒(nano-TiO2)对小鼠单核巨噬细胞超微结构的影响。方法:将不同浓度的nano-TiO2溶液加入小鼠单核巨噬细胞(Rawcell)中,在37℃、5%CO2的细胞培养箱中孵育4h,收集细胞,制样后在透射电镜下观察小鼠单核巨噬细胞超微结构的改变。结果:电镜下,nano-TiO2的粒径为20～35nm。致密的nano-TiO2通过内吞进入细胞,当浓度超过200μg/mL时,细胞胞质空泡内吞噬有大量成簇的致密颗粒,细胞核固缩,染色质浓缩、边集,出现早期细胞凋亡改变。

Objective：To study the ultrastructural effect of nano-TiO2 on cultured mouse monocyte-macrophage.Method：Mouse monocyte-macrophages（Raw cell）were incubated in culture medium containing nano-TiO2 of different concentration for 4h.The ultrastructural changes of mouse monocyte-macrophage were observed under electron microscope.Result：Under electron microscope,the diameter of nano-TiO2 is about 20～35 nm.The dense nano-TiO2 particles enter into the cytoplasm of mouse monocyte-macrophage by way of endocytosis.Various number of dense nano-TiO2 particles were found in the cytoplasmic vacuoles of different size of treated macrophages.The degree of severity of cell damage increased with the increase in concentration of nano-TiO2 in the culture medium.Apoptosis occurred in macrophages cocultured in high concentration of nano-TiO2（over 200 μg/mL）.