鼻咽癌双特异性抗独特型抗体体外抗肿瘤免疫机制初探(英文)  

In vitro anti-tumor immune mechanism of nasopharyngeal carcinoma bispecific anti-idiotype antibody

作　　者：王甲甲[1] 李亚林[1] 李跃辉[1] 李官成[1] 

机构地区：[1]中南大学肿瘤研究所,长沙410078

出　　处：《中南大学学报（医学版）》2010年第8期777-783,共7页Journal of Central South University ：Medical Science

基　　金：supported by Natural Science Foundation of Hunan (04JJ3098);Innovation Fund of Central South University(2009bsxt059), P.R.China

摘　　要：目的:比较鼻咽癌双价双特异性抗独特型抗体G22-I50与单价的抗独特型抗体G22,I50在体外抗肿瘤免疫情况,并对其可能的机制作初步探讨。方法:诱导表达G22-I50,G22,I50 3种蛋白并用Western印迹及ELISA方法进行活性鉴定。常规分离人外周血单个核细胞(PBMC),分别用G22-I50,G22,I50抗独特型抗体刺激并培养,采用MTT法、LDH释放法分别观察淋巴细胞增殖情况和细胞毒作用,ELISA法测定各抗独特型抗体刺激后培养上清液中IFN-γ,IL-2,IL-4的水平,流式细胞术检测刺激后淋巴细胞表型的改变。结果:Western印迹分析表明表达的G22-I50,G22,I50蛋白均可与FC2(Ab1)特异性地结合;直接ELISA结果表明复性后的蛋白已恢复活性,可用于体外实验研究。与G22、I50组相比,G22-I50刺激后的PBMC增殖明显,且对鼻咽癌细胞HNE2有特异的杀伤作用。G22-I50刺激后的PBMC培养上清液中IFN-γ,IL-2水平均比G22,I50组有所增加,而对IL-4水平没有明显影响。流式细胞术显示刺激后的PBMC中CD4+,CD8+T细胞比例增加,CD4+/CD8+比率增加,而CD4+CD25+T细胞的比例有所减少,其中以G22-I50组最为明显。结论:G22-I50具有更强的免疫原性并能增强PBMC的特异性杀瘤作用,其机制可能与促进PBMC的增殖,诱导具有抗肿瘤作用的Th1细胞因子的分泌并活化CD8+T细胞,抑制CD4+CD25+T细胞的表达有关。Objective To compare the in vitro antitumor immune responses induced by bivalent bispecific anti-idiotype antibody G22-I50 and monovalent anti-idiotype antibody G22 and I50,and explore its possible mechanism.Methods Proteins G22-I50,G22,and I50 were induced and identified by Western blot and ELISA.Peripheral blood monoclear cells（PBMC） were isolated and stimulated with G22-I50,G22,and I50 anti-idiotype antibodies,respectively.MTT assay and LDH release test were employed to examine the proliferation and cytotoxicity of the PBMC.The levels of IFN-γ,IL-2,and IL-4 in the supernatant were detected by ELISA and changes of T lymphocyte subsets were determined by flow cytometry.Results Western blot showed that G22-I50,G22,and I50 had specific binding capabilities to FC2（Ab1）.The activities of G22-I50,G22,and I50 had recovered and these proteins could be used in the in vitro study.The proliferation and cytotoxicity of the PBMC stimulated with G22-I50 were significantly higher than those stimulated with G22 or I50,The level of IFN-γ and IL-2 in the culture supernatant of the PBMC stimulated with G22-I50 was higher than that in the G22 or I50 group,but the level of IL-4 did not increase.Compared with the G22 or I50 group,the proportion of CD4＋ and CD8＋ T cells and CD4＋/CD8＋ ratio significantly increased,and the proportion of CD4＋CD25＋ T cells significantly decreased in the PBMC stimulated with G22-I50.Conclusion G22-I50 has more potent immunogenicity and would enhance specific antitumor effect which might relate to improving PBMC proliferation,inducing the secretion of Th1 type cytokines,activating CD8＋T cells,and suppressing the expression of CD4＋CD25＋ T cells.

关 键 词：抗独特型抗体 双特异 鼻咽癌 免疫机制 

分 类 号：R739.63[医药卫生—肿瘤]