Tang Zhiwen, Shangguan Dihua, Wang Kemin, Shi Hui, Sefah Kwame, Mallikratchy Prabodhika, Chen Hui William, Li Ying, Tan Weihong
Department of Chemistry, Shands Cancer Center, Center for Research at Bio/nano Interface, UF Genetics Institute, University of Florida, Gainesville, Florida 32611-7200, USA.
Anal Chem. 2007 Jul 1;79(13):4900-7. doi: 10.1021/ac070189y. Epub 2007 May 27.
In this paper, we describe a new way to generate molecular probes for specific recognition of cancer cells. Molecular medicine will require a large number of probes for molecular recognition and characterization of a variety of diseased cells. Aptamers, single-stranded DNA/RNA probes, are poised to become a chemist's antibody and have the potential to serve as molecular probes for a variety of biomedical applications. By applying newly developed cell-SELEX (cell-based systematic evolution of ligands by exponential enrichment) against whole living cells, panels of aptamers have been evolved from an initial DNA library to characterize target cells at the molecular level. Ramos cells, a B-cell lymphoma cell line, were used as target cells for the generation of effective molecular probes. By taking advantages of the repetitive and broad enrichment strategy, the selected aptamers could bind to target cells and other closely related cell lines in variant patterns with an equilibrium dissociation constant (Kd) in the nanomolar range. Some aptamers could also specifically recognize the target lymphoma cells mixed with normal human bone marrow aspirates. The cell-based SELEX is simple, fast, and robust. The strategies used here will be highly useful for aptamer selection against complex target samples in order to generate a large number of aptamers in a variety of biomedical and biotechnological applications, paving the way for molecular diagnosis, therapy, and biomarker discovery.
在本文中，我们描述了一种生成用于特异性识别癌细胞的分子探针的新方法。分子医学将需要大量用于分子识别和表征各种病变细胞的探针。适体，即单链DNA/RNA探针，有望成为化学家的抗体，并有可能作为用于各种生物医学应用的分子探针。通过针对完整活细胞应用新开发的细胞SELEX（基于细胞的指数富集配体系统进化），已从初始DNA文库中筛选出一组适体，以在分子水平上表征靶细胞。 Ramos细胞，一种B细胞淋巴瘤细胞系，被用作生成有效分子探针的靶细胞。通过利用重复和广泛的富集策略，所选适体可以以纳米摩尔范围内的平衡解离常数（Kd）以不同模式与靶细胞和其他密切相关的细胞系结合。一些适体还可以特异性识别与正常人骨髓抽吸物混合的靶淋巴瘤细胞。基于细胞的SELEX简单、快速且稳健。这里使用的策略对于针对复杂靶标样品进行适体选择将非常有用，以便在各种生物医学和生物技术应用中生成大量适体，为分子诊断、治疗和生物标志物发现铺平道路。
