中国组织工程研究 ›› 2017, Vol. 21 ›› Issue (6): 923-927.doi: 10.3969/j.issn.2095-4344.2017.06.018

• 药物控释材料 drug delivery materials • 上一篇    下一篇

转铁蛋白标记磁性脂质体的制备及体外成像

陈维翠1,刘淑仪1,林爱华2,刘  岘1
  

  1. 广州中医药大学第二附属医院,1影像科,2药学部,广东省广州市  510120
  • 收稿日期:2016-12-13 出版日期:2017-02-28 发布日期:2017-03-16
  • 通讯作者: 刘岘,博士,硕士生导师,副主任医师,广州中医药大学第二附属医院影像科,广东省广州市 510120
  • 作者简介:陈维翠,女,1986年生,广西壮族自治区贺州市人,汉族,硕士,主要从事影像诊断、分子影像学相关研究。
  • 基金资助:

    广东省科技计划项目(2013B021800247);国家自然科学基金青年项目(30700184)

Transferrin-labeled magnetolipsomes: preparation and magnetic resonance imaging in vitro

Chen Wei-cui1, Liu Shu-yi1, Lin Ai-hua2, Liu Xian1 
  

  1. 1Department of Radiology, 2Department of Pharmacy, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, Guangdong Province, China
  • Received:2016-12-13 Online:2017-02-28 Published:2017-03-16
  • Contact: Liu Xian, M.D., Master’s supervisor, Associate chief physician, Department of Radiology, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, Guangdong Province, China
  • About author:Chen Wei-cui, Master, Department of Radiology, the Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou 510120, Guangdong Province, China
  • Supported by:

    the Science and Technology Program of Guangdong Province, No. 2013B021800247; the National Natural Science Foundation of China, No. 30700184

摘要:

文章快速阅读:

 

文题释义:
转铁蛋白受体
:为跨膜糖蛋白,介导细胞内铁的摄取、参与细胞生长调节,且能在肿瘤细胞表面高度表达,是一种有效的肿瘤标志物,广泛应用于各类恶性肿瘤的靶向治疗。
磁性纳米粒子:以磁性材料为中心,包被生物高分子的核壳结构。磁性纳米粒具有良好的磁导向性和生物组织相容性,可与多种功能分子结合,如蛋白质、核酸、生物素等。

背景:利用转铁蛋白受体表达的特异性和转铁蛋白-转铁蛋白受体结合的亲和性,转铁蛋白修饰药物载体可以明显提高药物的特异结合能力和疗效。转铁蛋白也可修饰影像对比剂,针对肿瘤组织的转铁蛋白受体,实现肿瘤的特异性靶向成像。
目的:评价转铁蛋白-磁性纳米粒的理化特性,并对其细胞结合特性进行体外实验研究。
方法:采用旋转蒸发法制备磁性脂质体,共价结合法制备转铁蛋白-磁性纳米粒。对转铁蛋白-磁性纳米粒的粒径、电位、形态、转铁蛋白结合效率、r2弛豫率、细胞结合特性及细胞毒性等指标进行分析评价。转铁蛋白-磁性纳米粒与转铁蛋白受体高表达HepG2肝癌细胞特异性结合后进行体外MR成像。
结果与结论:①转铁蛋白-磁性纳米粒平均粒径为95.1 nm,多分散系数为0.21,Zeta电位为-1.25 mV,r2弛豫率为94.62 mmol-1•s-1,每个磁性脂质体约结合27个转铁蛋白分子;②荧光共聚焦电镜显示转铁蛋白-磁性纳米粒与转铁蛋白受体高表达HepG2肝癌细胞发生特异结合,荧光胞浆出现罗丹明红染;普鲁士蓝铁染色显示HepG2细胞内和细胞表面有铁染色颗粒;③体外细胞MR T2WI成像显示,转铁蛋白-磁性纳米粒与HepG2细胞标记后,离心管信号强度下降;而空白磁性纳米粒与细胞不发生结合,故无明显信号强度下降;④细胞毒性实验显示细胞生长曲线良好;⑤以上结果表明,转铁蛋白-磁性纳米粒满足MR分子探针的所需要求,可用于MR分子成像。

关键词: 生物材料, 纳米材料, 磁性脂质体, 转铁蛋白受体, 纳米粒子, 磁共振成像, 国家自然科学基金

Abstract:

BACKGROUND: Transferrin (Tf) is one suitable ligand to be conjugated to drug delivery systems to achieve site-specific targeting and desired therapeutic effect, due to its specific binding to transferrin receptors (TfR), and high expression on the surface of tumor cells. Contrast agents are also modified with Tf to achieve specific tumor imaging.
OBJECTIVE: To prepare Tf-labeled magnetoliposomes (MLs), and characterize their utility as TfR targeted MR specific contrast agent in vitro.
METHODS: MLs and Tf-MLs were prepared by lipid film hydration method and covalent coupling method, respectively. Tf-MLs were characterized by their mean size, zeta potential, polyindex, r2 relaxivity, Tf-binding efficacy and cytotoxicity. In vitro MRI contrasting properties of the suspended nanoparticles incubated with HepG2 cells were determined.
RESULTS AND CONCLUSION: The mean diameter, polydisperisity index, zeta potential and r2 relexivity of Tf-ML were 95.1 nm, 0.21, -1.25 mv and 94.62 mmol-1/s, respectively. The coupling efficiency was calculated and the values obtained were 59.4 μg Tf/μmol phospholipid corresponding to about 27 molecules of Tf-MLs. After a 2-hour incubation with rhodamine-labeled Tf-MLs, rhodamine fluorescence was detected intensively in the plasma membrane and the cytoplasm of the TfR-overexpressing HepG2 cells. In contrast, Tf-ML showed little binding in MCF-7 cells that had low TfR level. HepG2 cells incubated with Tf-ML showed much higher intracellualar iron density than incubated with non-targeted MLs. In vitro MR T2WI of cells demonstrated the centrifuge tube containing HepG2 cells incubated with Tf-MLs produced a lower visible signal intensity than that treated with non-targeted MLs. Tf-MLs showed their potentials such as high r2 relaxivity, specific binding ability characteristics. These results suggest the availability of Tf-MLs to serve as a targeted contrast agent.  

Key words: Liposomes, Receptors, Transferrin, Nanoparticles, Magnetic Resonance Imaging, Tissue Engineering

中图分类号: