中文摘要：

目的探讨携紫杉醇（Pac）和注射用曲妥珠单克隆抗体（Herceptin）高分子造影剂（Pac．PLGA—HER）联合超声体外寻靶能力及显影效果。方法通过双乳化法和碳二亚胺法制备载Pac靶向高分子造影剂。将MCF-7细胞种植于12个培养皿中，培养24h，分为4组，每组3个：非靶向造影剂组（Pac—PLGA组）、靶向造影剂组（Pac—PLGA—HER组）、靶向造影剂＋超声组（Pac—PLGA—HER＋超声组）和抗体封闭组。在激光共聚焦显微镜下对比观察高分子造影剂与细胞的结合能力。观察体外显影效果，并用DFY型定量仪进行定量，采用独立样本t检验进行统计学分析。结果靶向载Pac高分子造影剂平均粒径为（596±12）nm，体外寻靶能力实验显示靶向载Pac高分子造影剂可与MCF-7细胞大量结合。体外显影实验示靶向与非靶向载Pac高分子造影剂平均声强分别为（134．50±10．19）和（135．11±11．49）dB，平均灰阶分别为147．83±11．12和148．50±12．63，两者比较差异均无统计学意义（t均为一0．097，P均〉0．05）。结论携Pac和Herceptin的高分子造影剂对高表达HER2的人乳腺癌MCF-7有较强的结合能力，在体外显影实验中有较好的显影效果。

英文摘要：

Objective To further explore the affinity of paclitaxel-loaded and trastuzumab （Her- ceptin）-targeted poly（ lactic-co-glycolic acid, PLGA）-COOH ultrasound contrast agent （Pac-PLGA-HER） for human breast cancer cell line MCF-7 and study their effect on ultrasound imaging in vitro. Methods Paclitaxel-loaded PLGA-COOH ultrasound contrast agents （Pac-PLGA） were prepared by the double emul- sion technique and conjugated with Herceptin monoclonal antibody by 1-（3-dimethylaminopropyl）-3-ethyl- carbodiimide hydrochloride （EDC）/N-hyalroxysuccinimide （NHS）. MCF-7 cells were plated in culture di- shes for 24 h and divided into 4 groups with 3 dishes in each group, i.e. Pac-PLGA group, Pae-PLGA- HER group, ultrasound ＋ Pac-PLGA-HER group and antibody blocking group. Binding of polymer ultra- sound contrast agents to MCF-7 cells was observed by laser scanning eonfocal microscopy. In vitro experi- ments were employed to study the effects of Pac-PLGA-HER on the enhancement of ultrasound imaging as compared with Pac-PLGA, the control group. Independent samples t-test was used for statistical analysis with the help of DFY. Results The average diameter of Pac-PLGA-HER was （596 -＋ 12） nm. In the in vitro targeting study, a number of Pac-PLGA-HER bound with MCF-7 cells tightly; while, no conjugation was ob- served in the control group. During in vitro ultrasound imaging, the average sound intensity of Pac-PLGA- HER and Pac-PLGA was （ 134.50 ~ 10. 19） and （ 135.11 ＋ 11.49） dB （ t = - 0. 097, P 〉 0.05） and the average grey scale was 147.83 ＋ 11.12 and 148.50 ~ 12.63 （ t = - 0. 097, P 〉 0.05 ）, respectively. There was no difference between the two. Conclusion Pac-PLGA-HER could bind to high HER2-expressingMCF-7 cells specifically and effectively and was an effective ultrasound contrast agent in vitro.