携紫杉醇和Herceptin高分子造影剂联合超声体外寻靶及显影效果研究

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24 h,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-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.

Targeting and imaging study of paclitaxel-loaded and Herceptin-targeted ultrasound contrast agentwith ultrasound in vitro

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.