LHRH-PE40与Hela细胞表面LHRH受体结合的特异性及其细胞毒性

目的:研究重组免疫毒素LHRH-PE40与Hela细胞表面LHRH受体结合的特异性,并观察由此产生的细胞毒性作用.方法:ELISA方法检测LHRH-PE40与Hela细胞表面LHRH受体结合的高度特异性、饱合性及其与时间的关系;LHRH-PE40由LHRH受体介导对Hela细胞产生细胞毒作用进行光、电镜观察.结果:LHRH-PF40与Hela细胞表面受体的结合与正常鸡胚成纤维细胞的结合相比有显著意义(P＜0.01);LHRH-PE40与LHRH竞争LHRHR的OD值和TSH相比有显著意义(P＜0.01);光镜观察,LHRH-PE40对Hela细胞作用明显而对正常鸡胚成纤维细胞几乎没有作用;电镜观察,LHRH-PE40使Hela细胞表面出现凋亡征象.结论:与其他正常组织的细胞相比,Hela细胞膜表面LHRH受体分布呈过表达状;LHRH-PE40与细胞表面LHRH受体的结合具有高度特异性、饱和性;LHRH-PE40对细胞的作用由LHRHR介导,并且只对LHRHR阳性细胞产生毒性作用.

The binding specificity of LHRH-PE40 with LHRH receptor on the surface of Hela cell and its cytotoxicity

Objective: To study the binding specificity of recombination toxin LHRH-PE40 and luteinizing hormone releasing hormone (LHRH) receptor on the surface of Hela cells and the cytotoxicity of LHRH-PE40. Methods:We detected the high specificity in binding, saturation, time-course changes of LHRH-PE40 with LHRH receptor(LHRHR) on the surface of Hela cells by using ELISA method and compared the specificity with normal original chicken embryo fibroblast. The cytotoxicity of LHRH-PE40 to Hela cells mediated by its receptors was observed with light microscope (LM) and electronic microscope (EM).Results:The binding of LHRH-PE40 with LHRHR on the surface of Hela cells was significantly higher than that with the normal chicken embryo fibroblasts in control group(P<0.01). The LHRH-PE40 competed with LHRH for LHRHR(P<0.01) compared with TSH. Observed with LM,the cytotoxicity of LHRH-PE40 to Hela cells was more clearly than that to the normal chicken embryo fibroblasts. With electronic microscope, apoptosis of Hela cells induced by LHRH-PE40 was observed. Conclusion:Compared with the other normal cells, the distribution of LHRHR on the surface of Hela cells is strongly positive. The binding of LHRH-PE40 with LHRHR on the surface of cells shows high specificity and saturation. The function of LHRH-PE40 mediated by LHRHR to cells is only to those cells with positive expression of LHRHR.