Study of binding specificity and affinity of multimeric aptamers to trisialic acid and engineering of aptamer bio-dots for detecting polysialic acid on cell surfaces

Jinri Chen; Dong Xu; Qiang Huang; Shujun Wang; Fuhou Li; Shaojie Wu; Weixia Wang; Nandi Zhou

doi:10.1016/j.ijbiomac.2025.145413

Study of binding specificity and affinity of multimeric aptamers to trisialic acid and engineering of aptamer bio-dots for detecting polysialic acid on cell surfaces

Int J Biol Macromol. 2025 Jun 20;319(Pt 1):145413. doi: 10.1016/j.ijbiomac.2025.145413. Online ahead of print.

Authors

Jinri Chen¹, Dong Xu², Qiang Huang³, Shujun Wang², Fuhou Li², Shaojie Wu², Weixia Wang², Nandi Zhou⁴

Affiliations

¹ Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, 59 Cangwu Road, Haizhou 222005, China; State Key Laboratory of Genetic Engineering, MOE Engineering Research Centre of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China; Jiangsu Key Laboratory of Marine Biotechnology, 59 Cangwu Road, Haizhou 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, 59 Cangwu Road, Haizhou 222005, China; The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China. Electronic address: chenjinri@jou.edu.cn.
² Jiangsu Key Laboratory of Marine Bioresources and Environment, Jiangsu Ocean University, 59 Cangwu Road, Haizhou 222005, China; Jiangsu Key Laboratory of Marine Biotechnology, 59 Cangwu Road, Haizhou 222005, China; Co-Innovation Center of Jiangsu Marine Bio-industry Technology, 59 Cangwu Road, Haizhou 222005, China.
³ State Key Laboratory of Genetic Engineering, MOE Engineering Research Centre of Gene Technology, School of Life Sciences, Fudan University, Shanghai 200438, China.
⁴ The Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China. Electronic address: zhounandi@jiangnan.edu.cn.

PMID: 40545079
DOI: 10.1016/j.ijbiomac.2025.145413

Abstract

Polysialic acid (PSA) is a linear homopolymer composed of α-2, 8- and/or α-2, 9-glucosidic linked Neu5Ac. The overexpression of PSA on the cell surface is closely related to the invasion and metastasis of tumor cells. Herein, an ssDNA multimeric aptamer bio-dots was synthesized to replace complex biosensors for the study of polysialylation on cell surface. Firstly, the aptamer Apt3 (K_d = 114.0 nM) of trisialic acid (TSA) was truncated and optimized, and then the truncated aptamers were studied by dimeric and trimer aptamers, so as to obtain the multimeric aptamer Apt3-7 (K_d = 80.58 nM) of TSA. Then the newly obtained multimeric aptamer Apt3-7 was synthesized into aptamer bio-dots for detection of different cells such as human embryonic kidney cell 293 (HEK293 cells), human breast cancer cell 468 (MDA-MB-468 cells), human breast cancer cell 231 (MDA-MB-231 cells) and colorectal adenocarcinoma cell CACO-2 (CACO-2 cells) by confocal laser scanning microscopy (CLSM), and the results showed that the multimeric aptamer Apt3-7 bio-dots had good CLSM imaging effect in the detection of cancer cells. It can not only track cells dynamically in real time, but also has the characteristics of simple synthesis, relatively low cost, non-toxic to cells and friendly to operators.

Keywords: Cell surface; Multimeric aptamer bio-dots; Polysialic acid.