Pan Wei, Chen De-Sheng, Lu Yun-Juan, Sun Fen-Fen, Xu Hui-Wen, Zhang Ya-Wen, Yan Chao, Fu Lin-Lin, Zheng Kui-Yang, Tang Ren-Xian
Department of Pathogenic Biology and Immunology, Laboratory of Infection and Immunity, Xuzhou, Jiangsu 221004, P.R. China.
Department of Pathogenic Biology and Immunology, Laboratory of Infection and Immunity, Xuzhou, Jiangsu 221004, P.R. China; Department of Clinical Medicine, Xuzhou Medical University, Xuzhou, Jiangsu 221004, P.R. China.
Biomed Rep. 2017 Feb;6(2):181-187. doi: 10.3892/br.2016.827. Epub 2016 Dec 9.
The aim of the present study was to predict and analyze the secondary structure, and B and T cell epitopes of antigen 5 (Ag5) using online software in order to investigate its immunogenicity and preliminarily evaluate its potential as an effective antigen peptide vaccine for cystic echinococcosis. The PortParam program was used to analyze molecular weight, the theoretical isoelectric point, instability index and other physicochemical properties. The secondary structure of the Ag5 protein was predicted using Self-Optimized Prediction method With Alignment and the tertiary structure of the Ag5 protein was predicted using 3DLigandSite together with Center for Biological Sequence Analysis Prediction Servers. Furthermore, the Immune Epitope Database software was used to predict B cell epitopes, and T cell epitopes were predicted with the BioInformatics and Molecular Analysis Section and SYFPEITHI programs. The results demonstrated that α-helixes, β-turns, random coils and extended strands account for 23.35, 10.95, 41.32, and 24.38% of the secondary structure of the Ag5 protein, respectively. Ten potential B cell epitopes of Ag5 were identified as the amino acids sequences 27-39, 70-80, 117-130, 146-168, 250-262, 284-293, 339-349, 359-371, 403-412 and 454-462, and seven potential T cell epitopes were identified as the amino acid sequences 52-60, 57-65, 182-190, 231-239, 273-281, 318-326 and 467-475. Thus, ten B cell epitopes and seven T cell epitopes were identified on Ag5, suggesting the strong immunogenicity of this protein, which could be applied to design antigen peptide vaccines for echinococcosis.
本研究旨在利用在线软件预测和分析抗原5（Ag5）的二级结构以及B细胞和T细胞表位，以研究其免疫原性，并初步评估其作为囊性棘球蚴病有效抗原肽疫苗的潜力。使用PortParam程序分析分子量、理论等电点、不稳定指数和其他理化性质。利用带比对的自优化预测方法预测Ag5蛋白的二级结构，并使用3DLigandSite和生物序列分析预测服务器中心预测Ag5蛋白的三级结构。此外，使用免疫表位数据库软件预测B细胞表位，并用生物信息学和分子分析部门以及SYFPEITHI程序预测T细胞表位。结果表明，α螺旋、β转角、无规卷曲和延伸链分别占Ag5蛋白二级结构的23.35%、10.95%、41.32%和24.38%。Ag5的10个潜在B细胞表位被确定为氨基酸序列27 - 39、70 - 80、117 - 130、146 - 168、250 - 262、284 - 293、339 - 349、359 - 371、403 - 412和454 - 462，7个潜在T细胞表位被确定为氨基酸序列52 - 60、57 - 65、182 - 190、231 - 239、273 - 281、318 - 326和467 - 475。因此，在Ag5上鉴定出10个B细胞表位和7个T细胞表位，表明该蛋白具有较强的免疫原性，可用于设计棘球蚴病的抗原肽疫苗。
