免疫亲和质谱法研究β_2-微球蛋白抗原表位  

Characterization Epitope of the β_2-Microglobulin with Immunoaffinity Mass Spectrometry

作　　者：万翠红[1] 黎根[1] 刘志强[1] 刘淑莹[1] 

机构地区：[1]中国科学院长春应用化学研究所长春质谱中心,长春130022

出　　处：《化学学报》2008年第13期1572-1576,共5页Acta Chimica Sinica

基　　金：国家自然科学基金(No.20273067);中国科学院知识创新工程重要方向项目(No.KGCX2-SW-213-06);吉林省科技发展计划(No.20050556)资助项目

摘　　要：采用免疫亲和分离与质谱分析相结合的方法,对β2-微球蛋白抗原表位进行了系统研究.完整的抗原分子和已固定在载体(CNBr-activated Sepharose beads)上的单克隆抗体发生免疫亲和反应后,用Endoproteinase Glu-C,Trypsin,Aminopeptidase M和carboxypeptidase Y四种不同的蛋白酶依次酶解抗原分子,并采用基质辅助激光解析电离飞行时间质谱(MALDI-TOF-MS)技术对与抗体连接受保护而未发生水解的肽段进行了研究.结果表明:β2-微球蛋白抗原表位位于整个蛋白分子氨基酸序列的61～67位,即为SFYLLYY.通过合成肽段的分析,证明了SFYLLYY即为抗原表位,与亲和质谱方法分析结果一致.The approach for epitope mapping is the application of immunoaffinity separation and matrix assisted laser desorption/ionization （MALDI） mass spectrometry （MS）. The epitope of β2-microglobulin was identified with this approach. The antigen β2-microglobulin was coupled to a monoclonal antibody, which was covalently immobilized on a cyanogen bromide （CNBr）-activated Sepharose bead. Consecutive digestion of the antigen with endoproteinase GIu-C, trypsin, aminopeptidase M and carboxypeptidase Y resulted in affinity-bound peptides containing epitope. The bound peptides were identified by MALDI-TOF MS. The epitope recognized by the monoclonal antibody was identified to be the peptide fragment 61-67 with the sequence SFYLLYY. Synthesized peptide indicated the same result.

关 键 词：Β2-微球蛋白 抗原表位 免疫亲和 质谱 

分 类 号：R392[医药卫生—免疫学]