细粒棘球绦虫原头节抗原Eg-01883的B细胞表位预测、筛选及其血清学诊断价值  

Prediction, screening, and determination of the serological diagnostic value of B-cell epitopes of Echinococcus granulosus Eg-01883

作　　者：赵殷奇 徐士梅 朱明星 张婷瑞[2,4] 吕咏雪 赵瑞 赵巍 ZHAO Yin-qi;XU Shi-mei;ZHU Ming-xing;ZHANG Ting-rui;LV Yong-xue;ZHAO Rui;ZHAO Wei(Ningxia Institute of Medical Science,Yinchuan,Ningxia,China 750004;Science and Technology Center,Ningxia Medical University;Echinococcosis Laboratory,Ningxia Medical University;chool of Basic Medicine,Ningxia Medical University)

机构地区：[1]宁夏医学科学研究所,宁夏银川750004 [2]宁夏医科大学科技中心 [3]宁夏医科大学包虫病实验室 [4]宁夏医科大学基础医学院

出　　处：《中国病原生物学杂志》2019年第11期1277-1281,共5页Journal of Pathogen Biology

基　　金：宁夏自然科学基金项目(No.NZ17207);宁夏医科大学校级课题(No.XY2017013);国家自然科学基金项目(No.81360249)

摘　　要：目的应用计算机软件分析细粒棘球绦虫原头节特异性抗原分子Eg-01883,预测其可能形成的B细胞表位,并探讨其B细胞表位的免疫反应性及诊断价值。方法使用在线软件SOPMA及DNAStar分析Eg-01883的二级结构,采用SWISS-Model预测该蛋白的三级结构。应用在线软件ABCPred和IEDB结合其亲水性、柔韧性、表面可及性、抗原性等二级结构和三级结构对其B细胞表位进行分析预测、并人工合成表位肽段;以完整蛋白rEg-01883免疫小鼠产生的抗血清为一抗,采用间接ELISA方法筛选免疫反应性较强的表位,然后再以感染细粒棘球绦虫的小鼠血清为一抗,ELISA检测其免疫反应性,评价其诊断价值。结果初步筛选出7条抗原指数较高的Eg-01883表位,B细胞表位区域位于1-15、19-34、155-169、180-196、216-232、236-248、271-287位氨基酸。合成上述表位,纯度为99.99%。使用完整蛋白免疫血清筛选出2条反应原性较强的优势表位19-34和180-196,细粒棘球蚴感染小鼠血清能识别这两条B细胞表位,A450值结果分别为0.8218±0.0406和0.6398±0.0447,与对照组A_(450)值0.3312±0.0267和0.2961±0.0284比较差异均有统计学意义(P<0.05)。结论成功筛选到两个潜在的B细胞表位诊断抗原肽,对进一步开发细粒棘球绦虫早期诊断抗原和研究优势表位疫苗具有重要意义。Objective To use computer software to analyze Eg-01883,a specific antigen molecule of Echinococcus granulosus,in order to predict the possible formation of B-cell epitopes and to explore the immunoreactivity and diagnostic value of B-cell epitopes.Methods The secondary structure of Eg-01883 was analyzed using the online software SOPMA and DNAStar,and the tertiary structure of the protein was predicted using SWISS-Model.The online software ABCPred and IEDB were used to analyze the protein’s secondary and tertiary structure and characteristics such as hydrophilicity,flexibility,surface accessibility,antigenicity,B-cell epitopes,and artificial synthesis of epitope peptides.Antiserum was collected from mice immunized with rEg-01883,and the immunoreactive epitope was screened using ELISA.Serum from mice infected with E.granulosus was used as the primary antibody to evaluate its immunoreactivity and diagnostic value with ELISA.Results Seven Eg-01883 epitopes with a high antigenic index were initially screened.The B-cell epitopes were located at positions 1-15,19-34,155-169,180-196,216-232,236-248,and 271-287.These epitopes were synthesized with a purity of 99.99%.Two superior antigenic epitopes,19-34 and 180-196,were screened using Eg-01883 immunized serum.These two B-cell epitopes were recognized by the serum infected with E.granulosus.In comparison to the control,the A450 values in the epitope groups were 0.8218±0.0406 and 0.6398±0.0447;those values differed significantly from the values in the control groups(0.3312±0.0267 and 0.2961±0.0284)(P<0.05).Conclusion Two potential B-cell epitope peptides were successfully screened.This finding is crucial for identification of early diagnostic antigens of E.granulosus and development of epitope-based vaccines.

关 键 词：细粒棘球绦虫 诊断抗原肽 B细胞表位 rEg-01883 生物信息学 

分 类 号：R383.33[医药卫生—医学寄生虫学]