胃癌细胞特异性结合肽的筛选及鉴定

目的 筛选与胃癌细胞特异性结合的多肽。方法 以正常细胞为吸附细胞，胃癌细胞为筛选靶细胞对噬菌体随机12肽库进行消减筛，用细胞酶联免疫吸附试验（ELISA）、免疫细胞和组织化学法及裸鼠正常组织结合实验鉴定阳性克隆并进行DNA测序。结果 经三轮筛选，利用ELISA从随机挑选的24个噬菌体克隆中得到8个与胃癌细胞具有高结合力的噬菌体阳性克隆，经免疫细胞化学及裸鼠正常组织结合试验鉴定，发现第20、24两个克隆能与胃癌细胞特异性结合，而不与正常细胞和裸鼠组织结合，噬菌体阳性克隆氨基酸序列无同源性。结论 得到两个序列不同的特异性结合胃癌细胞的噬菌体克隆，这可为进一步的研究提供实验依据。

Screening and Characterization of Multipeptide Binding Specifically to Gastric Cancer Cells by Phage Peptide Library

Objective To screen and characterize multipeptides which bind specifically to gastric cancer cells by mean of screening from phage random 12 peptide library. Methods Gastric cancer cells were used as the target cells and normal cells as the absorber cells for substaction biopanning from a 12-mer peptide phage random peptide library. The stochastically selective positive phage clones were identified by using cell enzyme-linked immunosorbent assay (ELISA), immunocytochemistry, binding to nude mice tissue,and DNA sequencing. Results After 3 rounds of screening, 8 positive clones which can all bind to gastric cancer cells were obtained by ELISA, among which No.20, 24 positive clones can specifically bind gastric cancer cells but not bind to normal cells and nude mice tissue. No conserved motif was found in these peptides. Conclusion We screened Two peptides which can specifically bind to gastric cancer cells were screened from phage peptide library. This offered basic experimental data for further studying.