猪重要感染病毒蛋白的二级结构、抗原表位分析及三联表位多肽疫苗的重组预测

The secondary structure,antigen epitope analysis and recombination prediction triple epitope peptide vaccine of porcine important infection virus protein

为设计猪重要感染病毒的蛋白表位多肽疫苗,选取猪感染病毒的候选疫苗蛋白:猪繁殖与呼吸综合征病毒的GP5蛋白,猪圆环病毒2型的CAP蛋白,猪瘟病毒的E2蛋白。综合ABCpred和Bepi Pred方案,预测候选蛋白的B细胞表位;利用神经网络与量化矩阵法预测蛋白的CTL表位;采用MHC-Ⅱ类分子结合肽在线程序预测蛋白的Th表位。使用SOPMA方法与DNASTAR软件分析候选蛋白的二级结构,进一步验证B/T细胞表位预测结果的准确性。然后,通过Protean程序重组拼接获得的B/T细胞抗原表位。结果显示GP5蛋白具有4个优势B细胞表位,CAP、E2蛋白分别具有5个B细胞表位;GP5、CAP与E2蛋白各具有1个CTL表位;GP5、E2蛋白分别具有2个Th表位,CAP蛋白存在1个Th表位。二级结构分析显示预测获得的B/T细胞表位均处于蛋白易于产生表位的暴露表面、无规则卷曲与转角等位置,验证了B/T细胞表位预测结果的准确性。Protean程序重组拼接获得优势的B/T细胞抗原表位。最终设计获得抗原性较好的猪病毒三联表位多肽,为猪易感病毒的多联疫苗开发奠定基础。

In order to design protein epitope polypeptide for important infectious virus of porcine, the candidate proteins vaccine of swine infection virus was selected. The selected proteins included GP5 protein of PRRSV （ porcine reproductive and respiratory syn- drome virus）, CAP protein of PCV2 （ porcine circovirus type 2）, and E2 protein of CSFV （ classical swine fever virus）. ABCpred and BepiPred prediction programs were used to predict B cell epitopes, quantitative matrix, the artificial neural network was used to predict CTL cell epitopes, and an online server prediction was used to analysis MHC class 11 peptide binding affinity. The secondary structure further verifying the accuracy of B/T cell epitopes was analyzed by SOPMA and DNASTAR software. The BIT cell epitopes were re- composed by protean program. The results showed that GP5 protein had 4 B cell epitopes, CAP and E2 had 5 B cell epitopes, and GP5, CAP and E2 protein had 1 CTL cell epitopes. GP5 and E2 protein had 2 Th cell epitopes, and CAP protein had 1 Th cell epitopes. The secondary structure showed that most of the B/T cell epitopes were located in the exposed surface, the random coil and the comer, which verified the prediction accuracy of B/T cell epitopes. The B/T cell epitopes were recomposed by protean program, and triple epitope vaccine of porcine virus holding better antigen was designed finally, and laid the foundation for the development of swine virus multi vaccine.