精氨酸功能化羟基磷灰石纳米颗粒与人脐静脉内皮细胞的相互作用及机制

Interaction and mechanism between arginine functionalized hydroxyapatite nanoparticles and human umbilical vein endothelial cells

选用铽掺杂的精氨酸修饰的羟基磷灰石纳米颗粒(Arg@HAP^(Tb)NPs),探讨该纳米颗粒与细胞的相互作用以及Arg@HAP^(Tb)NPs在血管内皮细胞中的内吞机制。选取人脐静脉内皮细胞(HUVEC)作为研究的模型细胞,通过激光扫描共聚焦显微镜监测Arg@HAP^(Tb)NPs在细胞中的摄取情况,并通过细胞流速仪检测不同浓度下的细胞摄取后的平均荧光强度。结果表明,HUVEC吸收Arg@HAP^(Tb)NPs后主要定位在细胞质中,并主要分布在细胞核周围。Arg@HAP^(Tb)NPs的入胞过程具有时间和浓度依赖性,作用时间以4 h为宜,纳米颗粒的浓度以50 mg/L为最佳。Arg@HAP^(Tb)NPs入胞量明显强于未经精氨酸修饰的HAP^(Tb)NPs。Arg@HAP^(Tb)NPs进入HUVECs是一个能量依赖的主动运输过程,通过小凹蛋白介导的内吞作用发生。

The interaction between terbium-doped arginine functionalized hydroxyapatite nanoparticles(Arg@HAP^(Tb)NPs)and cells,and the hindered endocytosis mechanisms of human umbilical vein endothelial cells(HUVECs)were studied by observing the cell uptake of Arg@HAP^(Tb)NPs with laser scanning confocal microscopy.Average fluorescence intensity of cells after uptaking different concentrations of NPs was determined by flow cytometer.The results indicate that internalized Arg@HAP^(Tb) NPs mainly exist in the cytoplasm of HUVECs,and most of them distribute around the cell nuclei.The entrapment of Arg@HAP^(Tb)NPs shows time-dependent and concentrationdependent manners with optimal time of 4 h and concentration of 50 mg/L.Arginine modification significantly improves the uptake efficiency of HAP^(Tb)NPs.The entry of Arg@HAP^(Tb)NPs into HUVECs is mainly through concave protein-mediated endocytosis,an energy-dependent active transport process.