噬菌体表达短肽模拟日本血吸虫肝门型童虫表膜抗原表位的研究  

A short peptide mimicking epitopes of the membrane antigen of Schistosoma japonicum hepato-portal schistosomula using phage display techniques

作　　者：王敏[1] 易新元[2] 曾宪芳[2] 周东明[2] 袁仕善[2] 张顺科[2] 章洁[2] 

机构地区：[1]中南大学湘雅二医院检验科 [2]中南大学湘雅医学院寄生虫学教研室,长沙410078

出　　处：《中华微生物学和免疫学杂志》2003年第11期862-865,共4页Chinese Journal of Microbiology and Immunology

基　　金：WHO/TDR资助项目 (980 2 5 5 ) ;湖南省科委基金资助项目 (0 0jzy 2 115 )

摘　　要：目的　从噬菌体随机 12肽库免疫筛选日本血吸虫肝门型童虫表膜抗原 (SjHmAg)的模拟短肽分子 ,探讨其抗日本血吸虫的免疫保护效果。方法　以纯化的SjHmAg免疫血清IgG为配基免疫筛选噬菌体 12肽库 ,按吸附 洗脱 扩增的淘洗过程进行 3轮筛选 ;随机挑取噬菌体克隆用ELISA检测其特异性 ,并测序 ;用混和噬菌体克隆皮下免疫小鼠 3次 ,分别在 0、2、4周进行 ,第 6周每鼠经腹部感染 4 0± 1条日本血吸虫尾蚴 ,4 2d后剖杀冲虫 ,观察减虫及减卵效果。结果　经 3轮筛选 ,特异性噬菌体得到有效的富集 ,产出率为第一轮的 2 10倍 ;随机挑取 2 4个噬菌体克隆经ELISA鉴定 ,有 2 1个克隆能与SjHmAg免疫血清特异性反应 ;自动测序仪测序 ,结果发现它们的外源肽具核心序列 (STRKD) ;与对照组相比 ,混和噬菌体克隆免疫小鼠的减虫率为 16 .2 % ,减卵率为 5 9.0 %。结论　利用噬菌体展示技术可获得模拟SjHmAg短肽 ,这些短肽分子能诱导部分抗日本血吸虫保护力。Objective To obtain short peptides mimicking antigenic epitopes of the membrane antigen from Schistosoma japonicum hepato-portal schistosomula (SjHmAg), and to explore their protective immunity against Schistosoma japonicum (Sj) in mice. Methods IgG antibodies were purified from rabbit sera immunized with SjHmAg. The purified IgG was used to immunoscreen a phage random peptide library of 12 amino acids. Three rounds of biopanning were carried out, and 24 randomly selected positive clones were detected by ELISA and sequenced. Kunming mice were repeatedly immunized with mixed phage clones. Each mouse was challenged 40±1 Sj cercariae, and all mice were perfused 42 days after challenge. The worms and the eggs per gram liver tissue were counted. Results The specific phages binding to IgG were enriched 210 folds after three rounds of biopanning. Twenty-four clones were detected by ELISA, 21 of them were shown to actually bind to the specific IgG and sequenced, 7 clones had the core sequence (STRKD). Compared with the control groups. The reduction rates of the worm burden and liver egg were 16.15% and 59%, respectively. Conclusion The specific peptides mimicking epitopes of SjHmAg can be obtained by immunoscreening phage random peptide library and a protective immunity against Sj can be stimulated by these epitopes in mice.

关 键 词：日本血吸虫肝门型童虫 表膜抗原 表位 模拟短肽 免疫筛选 噬菌体随机肽库 

分 类 号：R446.5[医药卫生—诊断学]