肿瘤抗原MAGE-n HLA-A2限制性细胞毒性T细胞表位的预测及合成鉴定  

Prediction, synthesis and identification of HLA-A2-restricted cytotoxic T lymphocyte epitopes of the tumor antigen MAGE-n

作　　者：董海龙[1] 隋延仿[1] 叶菁[1] 李增山[1] 曲萍[1] 张秀敏[1] 陈广生[1] 禄韶英[1] 

机构地区：[1]第四军医大学病理教研室,西安710032

出　　处：《中华医学杂志》2003年第12期1080-1083,共4页National Medical Journal of China

基　　金：国家自然科学基金重点资助项目 ( 3 983 0 42 0 )

摘　　要：目的　采用表位重建技术 ,对预测MAGE n抗原HLA A2限制性CTL表位结合活性进行研究。方法　用SYFPEITHI超基序法远程预测系统和量化基序多项式法结合的预测方法 ,筛选新的MAGE n抗原HLA A2限制性CTL表位作为候选表位。对预测的抗原表位进行多肽合成 ,并用HPLC进行纯化 ,质谱法 (MS)鉴定。候选表位与HLA A2位点的亲和力及结合稳定性用竞争结合抑制实验、T2结合稳定性实验及MHC 肽复合体稳定性实验测定。结果　用表位预测法筛选MAGE n抗原 5个HLA A2限制性CTL表位为候选表位。QLVFGIEVV(15 9 16 7)、IMPKTGFLI(195 2 0 3)和FLIIVLVMI(2 0 1 2 0 9) 3个表位具有较高的HLA A2结合力 (IC50 <15 μM)和结合稳定性 (DT5 0 >6h) ,可作为MAGE n抗原HLA A2限制性CTL候选表位进行进一步研究。结论　表位预测结合表位重建方法可提高肿瘤抗原CTL表位研究的效率。MAGE n抗原HLA A2限制性CTL表位经免疫学鉴定后 ,可望用于新型肝癌治疗性多肽疫苗的设计研究 ,为临床肝癌特异性治疗奠定基础。Objective To predict, synthesize, and identify HLA-A2-restricted cytotoxic T lymphocyte (CTL) epitopes of the tumor the novel antigen MAGE-n. Methods Long-distance prediction system SYFPEITHI combined with polynomial method was used to predict the HLA-A2-restricted CTL epitopes of the tumor antigen MAGE-n. The candidate epitopes were synthesized with solid phase strategies, purified with reverse phase high-performance liquid chromatography and identified by mass spectrometry, The binding affinity and biding stability of the synthesized peptides were examined by cellular competition-based HLA-A2 peptide binding assay, T2 peptide stabilization assay, and peptide-major histocompatibility complex dissociation assay. Results Five HLA-A2-restricted CTL epitopes of MAGE-n were selected: The epitopes QLVFGIEVV (159-167), IMPKTGGLI (195-203), and FLIIVLMI (201-209) with high HLA-A2 binding affinity (LC 50<15 μmol/L) and binding stability (DT 50>6 h) were selected as candidate epitopes for further study in immunotherapy for tumor. Conclusion Epitope prediction combined with epitope reconstruction improves the study of HLA-A2-restricted CTL epitopes of the tumor antigen MAGE-n. The selected epitopes of MAGE-n may be used in the design of therapeutic peptide vaccine for hepatocellular carcinoma.

关 键 词：肿瘤抗原 MAGE-N HLA-A2 细胞毒性 T细胞 表位重建技术 免疫学鉴定 肝癌 

分 类 号：R730.3[医药卫生—肿瘤]