核酸适配体功能化磁珠在转移性大肠癌细胞富集中的应用  

Application of Aptamer-functionalized Magnetic Beads in Enrichment of Metastatic Colorectal Cancer Cells

作　　者：李婉明[1] 方瑾[1] LI Wan-Ming;FANG Jin(Key Laboratory of Cell Biology,Ministry of Public Health,Key Laboratory of Medical Cell Biology,Ministry of Education,Department of Cell Biology,School of Life Sciences,China Medical University,Shenyang 110122,China)

机构地区：[1]中国医科大学卫生部细胞生物学重点实验室,医学细胞生物学教育部重点实验室,细胞生物学教研室,生命科学学院,沈阳110122

出　　处：《分析化学》2021年第5期710-717,共8页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(Nos.81672920,82073291);辽宁省自然科学基金项目(No.2020-MS-164);沈阳市中青年科技创新人才支持计划项目(No.RC190261)资助。

摘　　要：基于核酸适配体对转移性肿瘤细胞高亲和力和高特异性的靶向识别功能,采用生物素-链霉亲和素的交联方法,将核酸适配体W3修饰在磁珠微球上,形成特异性识别转移性大肠癌细胞的功能化磁珠(W3-beads),实现对转移性大肠癌细胞的靶向捕获和富集。核酸适配体W3在室温条件和人血浆环境下可保持对靶细胞的特异性结合能力,制备的修饰磁珠W3-beads可在不同比例的靶细胞/非靶细胞混合细胞中有效捕获靶细胞。W3-beads对不同靶细胞数进行捕获时,在细胞数量超过10^(3)cell/mL时捕获效率超过75%,实际检出限达到50 cell/mL;初始细胞数量与捕获细胞数量之间的校准公式为y=0.7253 x-5.1199(R^(2)=0.9967)。将靶细胞掺入全血中模拟循环肿瘤细胞,W3-beads可对全血中靶细胞实现有效地捕获和富集。本研究构建的W3-beads对转移性大肠癌细胞具有良好的靶向捕获、分离和富集能力,可为大肠癌患者血样中循环肿瘤细胞的富集提供有效简便的工具。Based on the high affinity and specific target recognition function of the aptamer for metastatic tumor cells,aptamer-functionalized magnetic beads(W3-beads)that could specifically recognize and enrich metastatic colorectal cancer cells were formed using the biotin-streptavidin cross-linking method.Aptamer W3 maintained specific binding ability to target cells at room temperature and in human plasma environment.W3-beads prepared by modifying magnetic beads effectively captured target cells in mixed cells of target cells/non-target cells in different ratios.When the number of target cells exceeded 10^(3) per milliliter,the capture efficiency of W3-beads exceeded 75%,and the actual detection limit reached 50 cells per milliliter.Besides,the calibration formula between the initial number of cells and the number of captured cells was y=0.7253 x-5.1199(R^(2)=0.9967).Incorporating target cells into whole blood to simulate circulating tumor cells,W3-beads effectively captured and enriched target cells in whole blood.The aptamer-functioned magnetic beads constructed in this experiment had good targeted capture,separation and enrichment capabilities for metastatic colorectal cancer cells,and provided an effective and convenient tool for enrichment of circulating tumor cells in the blood samples of colorectal cancer patients.

关 键 词：循环肿瘤细胞 适配体 磁珠 富集 转移性大肠癌 

分 类 号：R735.34[医药卫生—肿瘤]