Objective: To explore the interaction between arginine functionalized hydroxyapatite (HAP/Arg) nanoparticles and endothelial cells, and to investigate mechanisms for endocytosis kinetics and endocytosis.
Methods: Human umbilical vein endothelial cells (HUVECs) were selected as the research model.Cellular uptake of HAP/Arg nanoparticles were observed by laser scanning confocal microscopy.Average fluorescence intensity of cells after ingestion with different concentrations of HAP/Arg nanoparticles were determined by flow cytometer and atomic force microscopy.
Results: The HAP/Arg nanoparticles with doped terbium existed in cytoplasm, and most of them distributed around the nucleus area after cellular uptake by HUVECs. Cellular uptake process of HAP/Arg nanoparticles in HUVECs was in a time and concentration dependent manner. 4 h and 50 mg/L was the best condition for uptake. HAP/Arg nanoparticles were easier to be up-taken into the cells than HAP nanoparticles without arginine functionalized.
Conclusion: HAP/Arg nanoparticles are internalized by HUVECs cells through an active transport and energy-dependent endocytosis process, and it is up-taken by cells mainly through caveolin-mediated endocytosis, but the clathrin-dependent endocytic pathway is also involved..
目的：选取自备的铽掺杂的精氨酸表面修饰的羟基磷灰石(arginine functionalized hydroxyapatite，HAP/Arg)纳米颗粒，研究该纳米颗粒与细胞的相互作用及血管内皮细胞对HAP/Arg纳米颗粒的内吞动力学和内吞入胞的相关机制。方法：选取人脐静脉内皮细胞(human umbilical vein endothelial cells，HUVECs)作为研究模型细胞，利用激光扫描共聚焦显微镜观察HAP/Arg纳米颗粒的细胞摄取，利用细胞流式仪及原子力显微镜测定不同浓度下细胞摄取后的平均荧光强度。结果：铽掺杂的HAP/Arg纳米颗粒被HUVECs摄取后主要存在于细胞质中，而且大部分分布在细胞核区域周围。HAP/Arg纳米颗粒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。精氨酸修饰的HAP纳米颗粒入胞量明显强于未经精氨酸修饰的HAP纳米颗粒。结论：HAP/Arg纳米颗粒进入HUVECs是一个主动转运的能量依赖的过程，以网格蛋白和小凹蛋白介导的内吞相结合的细胞跨膜转运机制，但以小凹蛋白介导内吞途径为主。.