单克隆抗体MS57-2.1在胃癌生物学中的实验研究

Experimental study on monoclonal antibody MS57-2.1 in biology of gastric cancer

目的:鉴定单克隆抗体MS57-2.1(简称MS57-2.1单抗)的胃癌特异性,研究MS57-2.1单抗的体外和体内抑瘤功能,为胃癌的靶向治疗提供候选抗体药物。方法:本课题组前期利用4个胃癌细胞株膜蛋白免疫A/J小鼠,通过杂交瘤联合高通量流式细胞技术筛选并获得抗胃癌MS57-2.1单抗。通过流式细胞和ELISA检测MS57-2.1单抗的胃癌特异性。通过免疫荧光技术鉴定MS57-2.1单抗的靶抗原在胃癌细胞的定位。通过体外和体内实验初步研究MS57-2.1单抗抑制胃癌细胞移动以及侵袭的作用。结果:流式细胞检测结果表明MS57-2.1单抗可以高亲和力与特定胃癌细胞株结合,而几乎不与正常人外周血细胞结合。ELISA结果表明MS57-2.1单抗可与胃癌组织膜蛋白结合,而不与幽门螺杆菌及胃癌细胞分泌蛋白结合。免疫荧光检测表明MS57-2.1单抗的靶抗原定位于胃癌细胞膜表面。在Transwell小室迁移和侵袭实验中,MS57-2.1单抗处理后胃癌细胞MKN45和BGC823移动能力受到明显抑制,穿过小室细胞数和穿膜细胞数显著低于无关同型单抗对照组和空白对照组。在裸鼠实验中,MS57-2.1单抗处理组的裸鼠肿瘤播散程度显著低于无关同型单抗对照组和空白对照组。结论:MS57-2.1单抗具有抑制胃癌细胞迁移、侵袭和播散的作用,是胃癌靶向治疗具有潜在应用价值的候选抗体药物。

Objective To identify the gastric cancer（GC）-specificity of MS57-2.1 monoclonal antibody（mAb）, and to investigate the biological function of MS57-2.1 mAb in vitro and in vivo. Methods Hybridoma technology was applied to produce the monoclonal antibodies using membrane proteins from four GC cell lines immune A/J mice. Hybridoma and HTS-FACS was used to screen and produce the monoclonal antibody. Then one of the MS57-2.1 mAb was produced. The gastric cancer-specificity of MS57-2.1 mAb was detected by FACS and ELISA. Immunofluoscence was used to explore the location of target antigen of MS57-2.1 mAb. The potential effect of MS57-2.1 mAb in inhibiting GC cell migration and invasion were tested with transwell experiment and nude mice model with peritoneal metastasis. Results It was shown with FACS that MS57-2.1 mAb could bind to certain GC cell lines with high affinity but hardly bind to normal peripheral blood cells. It was indicated by ELISA that MS57-2.1 mAb was able to bind to GC membrane proteins but not to the H. pylori or to the GC secreting proteins. Immunofluorescence proved that the target antigens of MS57-2.1 was located on the membrane of GC cells. Both migration and invasion of Transwell was used to showed that the number of gastric cancer cells crossing through chambers in MS57-2.1 mAb group were significantly lower than that in the irrelevant mAb group and in blank control group. In in vivo study of nude mice with peritoneal metastasis the nude mice in MS57-2.1 mAb group had less tumor peritoneal metastasis than that in the nude mice in irrelevant control mAb group or blank control group. Consequently, it was shown that MS57-2.1 mAb inhibited the migration and invasion of GC cells. Conclusions The MS57-2.1 mAb can bind GC cells specifically and inhibit the migration and invasion of GC cells.