利用噬菌体展示技术筛选放射性标记肺癌靶肽YC11及其生物分布

Screening,Radiolabeling and Biodistribution of Lung Tumor-targeting Peptide YC11 by in vivo Phage Display

利用体内噬菌体展示技术筛选了肿瘤特异性结合靶肽,获得了肺腺癌靶肽CSIHYPLSC(YC11)并对其进行了放射性碘标记.采用反相高效液相色谱技术(RP-HPLC)分离纯化131I-YC11和对照肽131I-NGR,放化纯度大于99%.在荷人肺腺癌A549裸鼠体内的分布结果表明,131I-YC11的肿瘤/血液放射性计数比为0.62,肿瘤/心脏放射性计数比为2.06,肿瘤/肺放射性计数比为1.11,肿瘤/肝脏放射性计数比为0.81,略高于131I-NGR的对应值.131I-YC11在肿瘤中的摄取值为2.79%ID/g,与131I-NGR在肿瘤中的摄取值(1.61%ID/g)相比,131I-YC11的肿瘤摄取高于多肽131I-NGR.

In vivo phage display was used to isolate tumor-targeting peptides. A cycloheptapeptide CSIHY- PLSC（ YC11 ） ligand targeting A549 human lung tumor was identified and radioiodinated. The labeled com- plex 1311-YCll and 131I-NGR（control peptide） were isolated and purified by reverse phase high-performance liquid chromatography（RP-HPLC）. The radiochemical purity was estimated to be better than 99%. The bio- distribution results of 131I-YCll and control peptide 131I-NGR in mice bearing A549 tumor demonstrated that the tumor-to-blood, tumor-to-heart, tumor-to-lung and tumor-to-liver uptake ratios of 131i_YCll were 0. 62, 2.06, 1.11 and 0. 81, respectively, and slightly higher than those of 131I-NGR. The uptake of 131I-YCll in tumor was 2.79% ID/g, more than that of 1311-NGR （1.61% ID/g）. 1311-YC 11 was more concentrated in A549 tumor than 131I-NGR. Conclusively, YC11 could be a potential lung cancer targeting agent.