肿瘤干细胞表面标记物CD133高亲和结合肽的筛选  

Initial screening of binding-peptide of the cell surface marker CD133 of cancer stem cells

作　　者：孙晋敏[1] 张超[1] 李学农[1] 

机构地区：[1]南方医科大学病理学系广东省分子肿瘤病理学重点实验室,广州510515

出　　处：《北京大学学报（医学版）》2008年第5期476-479,共4页Journal of Peking University:Health Sciences

基　　金：国家自然科学基金(30770975);广东省科技计划项目(2007B031001001)资助~~

摘　　要：目的:应用噬菌体肽库技术筛选肿瘤干细胞表面标记物CD133特异性结合短肽,为干细胞研究、肿瘤治疗及抗肿瘤转移研究提供新的技术和工具。方法:利用链霉亲和素与生物素的高度亲和力,以生物素标记的鼠CD133细胞外段(bio-CD133)为靶,对噬菌体七肽库进行液相筛选,应用夹心ELISA选择出结合较强的克隆,提取DNA并测序,通过竞争性阻断实验验证其特异性。结果:通过三轮体外液相筛选,得到结合能力较强的高亲和结合肽,5条完全一致的重复序列为APSPMIW和3条完全一致的重复序列为LQNAPRS,竞争性阻断实验证实其特异性较强。结论:利用噬菌体肽库技术成功地筛选出具有较高亲和力和特异性的CD133结合肽,表明以生物素标记的小分子多肽为靶筛选结合肽的技术具有可行性。Objective：To select the binding-peptide of the cell surface marker CD133 of cancer stem cells from phage peptide library, and to find a new tool for research on stem cells, tumor therapy and anti-metastasis of cancer. Methods： Biotined mouse CD133 extracellular fraction was used as a target to screen phage 7-peptide library by the high affinity of streptavidin and biotin, and the clones were identified by sandwich ELISA and competitive experiment. Single strand DNA was extracted from these positive clones and was analyzed by single-strand dideoxy-sequencing. Results： After three turn solution panning, five peptides with high affinity shared the same amino acid sequence： APSPMIW and three identical peptides with high affinity shared the same amino acid sequence： LQNAPRS. Conclusion： The peptides that bind with mouse CD133 extracellular fraction with high affinity and specificity were first screened from the phage peptide library for the first time, which initially indicates that the feasibility of screening from phage peptide library with small molecule polypeptide biotined as a target.

关 键 词：肿瘤干细胞 细菌噬菌体 肽库 肿瘤转移 

分 类 号：R730.21[医药卫生—肿瘤]