用噬菌体表面展示技术筛选与肝癌细胞系结合的抗体模拟肽  

Screening the antibody mimic peptide binding to hepatocellular carcinoma cells by phage display technique

作　　者：李韩平[1] 郑玉玲[1] 周宏[2] 熊正英[3] 姜永强[1] 

机构地区：[1]军事医学科学院微生物流行病研究所病原微生物与生物安全国家重点实验室,北京100071 [2]军事医学科学院生物工程研究所,北京100071 [3]陕西师范大学运动生物学研究所,陕西西安710062

出　　处：《细胞与分子免疫学杂志》2005年第4期452-455,共4页Chinese Journal of Cellular and Molecular Immunology

基　　金：国家自然科学基金资助项目(No.30171091;30271478);北京市自然科学基金资助(No.7022031)

摘　　要：目的:从噬菌体展示肽库中,筛选可与肝癌细胞特异性结合的抗体模拟肽。方法:通过生物淘选使噬菌体富集。利用ELISA法,鉴定噬菌体单克隆原种的亲和性,并进行统计学分析。通过竞争ELISA,分析筛选所得抗体模拟肽的结合位点,并进一步分析抗体模拟肽的序列组成。结果:随着淘选次数的增加,出现噬菌体的富集。ELISA的结果显示,相对于正常肝细胞,筛选所得环状7肽对肝癌细胞系SMMC7721和BEL7402均有良好的结合活性(P<0.05),且与SMMC7721细胞的结合活性明显优于与BEL7402细胞的亲和性(P<0.05)。在α=0.01的水平上,7肽单克隆噬菌体原种可明显与scFv竞争结合SMMC7721细胞(0.005<P<0.01)。竞争性ELISA的结果显示,scFv在一定浓度(0～10-5)范围内,随着scFv浓度的逐渐降低,竞争抑制率也在逐渐减小。测序结果证实,所挑选的7肽阳性克隆的测序结果均相同。结论:通过淘选获得的抗体模拟肽(CLPRQSSFC)是有效的,为导向治疗提供了新的实验依据。AIM: To screen the antibibody mimic peptide binding to hepatocellular carcinoma (HCC) from the circular 7-mer peptide libraries. METHODS: The enrichment of phage was achieved by repetitious biopanning. The affinity of peptide was evaluated by ELISA, and the binding site of the peptide was analysed by the competition ELISA . RESULTS: The output of phage gradually rose along with increasing of biopanning times. The obtained circular 7-mer peptide showed good binding activity to hepatocellular carcinoma cell lines SMMC-7721 and BEL-7402 (P<0.05), and its affinity to SMMC-7721 cells was superior to BEL-7402 (P<0.05) . At the level of α=0.01, the screened 7-mer peptide monoclonal stocks could obviously compete with scFv to bind SMMC-7721 cells (0.005<P<0.01). As the concentration of scFv gradually fell, the competition inhibition rate dropped accordingly. Sequence analysis showed that the sequences of 7-mer positive monoclonal stocks were identical. CONCLUSION: The peptide obtained through biopanning was specific and effective, which may provide further support for target therapy of HCC.

关 键 词：噬菌体肽库 淘选 肝细胞癌 

分 类 号：R392.11[医药卫生—免疫学]