β_2-微球蛋白连续表位的免疫亲和质谱研究  

Characterization of Linear Epitope of the β_2-Microglobulin via Combination of MALDI-TOF-MS with Immunoaffinity

作　　者：黎根[1] 刘宁[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

出　　处：《高等学校化学学报》2007年第1期92-96,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:20273067);中国科学院知识创新工程重要方向项目(批准号:KGCX2-SW-213-06)资助

摘　　要：采用Endoproteinase Glu-C，Lys—C和Trypsin 3种蛋白酶分别水解β2-微球蛋白，产生一系列肽段，利用固定在琼脂糖珠上的单克隆抗体与其发生免疫亲和反应．利用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF—MS）技术，对抗原决定簇肽段-抗体复合物进行系统研究，结果表明，与抗体结合部位即连续表位的位点为肽段（59—69）（DWSFYLLYYTE）．该研究方法简便、准确，可用来对其它抗原连续表位的快速测定．Matrix-assisted laser desorption ionization time-of-flight mass spectrometry （MALDI-TOF-MS）, in combination with immunoaffinity provided a powerful tool for determining epitope （antigenic determinant） in protein. The linear epitope of the β2-microglobulin was characterized in the paper. The method as follows ： at first β2-microglobulin was digested by a proteolytic enzyme to produce an appropriate set of peptide fragments, then peptide fragments containing the linear epitope were selected and separated from the pool of peptide fragments by immunoprecipitation with the monoclonal antibody. The agarose beads were collected carefully after the reaction. Unbound peptides would be washed away, while the peptides containing the epitope would remain bound to the immobilized antibody after the beads were washed several times with appropriate buffer. At last the masses of the bound peptides were identified directly by MALDI-TOF MS. Using Endoproteinase Glu- C Endoproteinase Lys-C and Trypsin in the experiment, the linear epitope of β2-microglobulin was located within peptide fragment 59-69, that is, DWSFYLLYYTE.

关 键 词：基质辅助激光解吸电离飞行时间质谱 免疫亲和 Β2-微球蛋白 连续表位 单克隆抗体 

分 类 号：O629.7[理学—有机化学] O657.63[理学—化学]