可诱导共刺激分子-Ig融合蛋白的理化性质和体内生物学活性分析  

Physicochemical properties and biological activity of a recombinant inducible co-stimulator-Ig fusion protein

作　　者：张鹏[1] 王振猛[2] 秦琴[1] 王健[1] 沈茜[1] 

机构地区：[1]第二军医大学长海医院实验诊断科,上海200433 [2]第二军医大学东方肝胆外科医院麻醉科,上海200438

出　　处：《第二军医大学学报》2010年第2期128-131,共4页Academic Journal of Second Military Medical University

基　　金：国家高技术研究发展计划("863"计划)(2002AA214091);国家自然科学基金青年基金(30500501)~~

摘　　要：目的对自行研制的可诱导共刺激分子-Ig融合蛋白的理化性质和体内生物学活性进行分析鉴定。方法采用HCl水解法、Edman法、胰酶消化MALDI-TOF-MS质谱法分别测定该融合蛋白的氨基酸组成、N末端15个氨基酸序列、肽谱等理化性质,并通过CFSE标记体内检测淋巴细胞增殖反应实验研究其抑制同种淋巴细胞增殖的生物学活性。结果氨基酸组成分析测得样品的氨基酸组成与ICOS-Ig理论值基本一致。蛋白N末端15个氨基酸序列为EINGSANYEM-FIFHN,与ICOS-Ig理论值一致。MALDI-TOF-MS质谱测定共获得6个与理论预测值相符的肽段。ICOS-Ig可以明显抑制同种T细胞的体内增殖反应。结论所研制的可诱导共刺激分子-Ig融合蛋白结构表达正确且具有体内抑制同种淋巴细胞增殖的活性,为该融合蛋白的质量标准研究奠定了基础。Objective To investigate the physicochemical properties and biological activity of self-prepared fusion protein inducible co-stimulator-Ig.Methods Acid hydrolysis,edman degradation and peptide mass finger printing were used to determine the amino acid composition,N-terminal 15 amino acid sequences,and peptide mapping.In vivo mixed lymphocyte reaction assay was used for identification of its biological activity.Results The result of amino acids composition analysis was consistent with the theoretical value of ICOS-Ig.N-terminal 15 amino acid sequences of the product were EINGSANYEMFIFHN,consistent with the theoretical value of ICOS-Ig.Peptide match assay identified six peptides of the product which could match the theoretic maps of ICOS-Ig.ICOS-Ig and CsA noticeably inhibited the proliferation of allo-reactive T cells in vivo.Conclusion The prepared ICOS-Ig fusion protein has a correct structure and can inhibit the proliferation of allogeneic T cells in vivo,which lays a foundation for quality control of ICOS-Ig fusion protein.

关 键 词：ICOS-Ig融合蛋白 氨基酸组成 氨基酸序列 肽谱 淋巴细胞增殖 

分 类 号：R392.111[医药卫生—免疫学]