摘要
目的 筛选钙蛋白酶 (calpain)的B细胞表位 ,探讨其B细胞表位的免疫原性及其所诱导的免疫应答类型。方法 用Genetyx MAC9.0分析calpain肽连的亲水性 ,在亲水性区域以 9个氨基酸为肽链单位的固相重叠肽链库 (每相邻两个肽链之间仅有一个氨基酸不同 )被Auto spotRobot制备 ,用Dot ELISA在合成的肽链库上筛选B细胞表位 ,含有B细胞表位的肽链免疫BALB c小鼠 ,ELISA鉴别特异性IgG抗体亚类的产生。结果 由 75 8个氨基酸组成的日本血吸虫calpain蛋白含有 2个主要的亲水区 ,其存在区域分别在氨基酸 2 2 9～ 375和 5 5 5～ 6 13;当我们测定合成的肽链文库时 ,在亲水区内筛选出 4个B细胞的表位 ,分别是氨基酸 2 34～ 2 5 1(YAHLSGGT) ;2 90～ 2 97(CLMGCSIH) ;338～ 34 6(PWGDSHEW) ;35 8～ 36 4(AWCDGAPQ) ;与对照组鼠相比较免疫鼠血清中IgG1、IgG2a、IgG2b特异性抗体有显著性意义的上升。结论 日本血吸虫calpain是一个具有免疫原性的蛋白 ,能够激发宿主产生高水平的免疫球蛋白 ,提示calpain的B细胞表位可以成为日本血吸虫病的诊断抗原和日本血吸虫疫苗候选分子。
Objective To select B cell epitopes of calpain and to explore antigenicity of the B cell epitope and immune respose type induced by the B cell epitopes. Methods Hydrophilicity of predicted calpain amino acid sequence was analyzed by Genetyx-MAC9.0. Overlapping 9-mer oligopeptides spanning hydrophilic portions of residues 229-375 and 555-613 were synthesized in solid phase by Auto-spot Robot. Dot-ELISA to detect liner epitopes for B cell epitopes in synthesizing peptides library. BALB/c mice were immunized by B cell epitope, IgG antibodies subclass of immunized mice were detected by ELISA. Results Two major hydrophilic portions of Schistosoma japonicum(S.japonicum) calpain were predicted which located at residues 229-375 and 555-613. There were four common B cell epitopes in schistosomal calpain as 234-251(YAHLSGGT); 290-297(CLMGCSIH); 338-346(PWGDSHEW); 358-364(AWCDGAPQ); After 4 weeks of being immunized with B cell epitopes, IgG1, IgG2a and IgG2b antibodies significantly increased in sera of immunized mice compared with control ones. Conclusion Together with these results, calpain of S.japonicum indicated strong antigenicity which seems to be not only a vaccine candidate, but also a target antigen for immuno diagnosis of human schistosomiasis.
出处
《中华微生物学和免疫学杂志》
CAS
CSCD
北大核心
2002年第4期411-414,共4页
Chinese Journal of Microbiology and Immunology
