日本血吸虫SjZFP1 181-786bp基因序列编码蛋白的免疫保护效果评估

RECOMBINANT PROTEIN COVERING 181-786BP IN SJZFP1 ENCODING GENE OF SCHISTOSOMA JAPONICUM DOES NOT INDUCE PROTECTION

根据日本血吸虫锌指蛋白SjZFP1的抗原位点预测结果,选取编码基因中抗原表位富集的181~786 bp核苷酸序列(SjZFP1-1)表达制备重组蛋白抗原rSjZFP1-1/His,构建重组真核表达质粒pcDNA-SjZFP1-1,并开展动物免疫实验,评估免疫保护效果。在两次独立的免疫实验中,与相应对照组相比,rSjZFP1-1/His单独免疫组以及pcDNA-SjZFP1-1与rSjZFP1-1/His联合免疫组均产生较高水平的特异性抗体,但平均虫负荷、肝脏虫卵数无显著性减少。研究结果显示rSjZFP1-1/His不能诱导有效的抗感染免疫,今后可进一步开展SjZFP1蛋白N-端肽段编码序列的表达和效果评估。

Prediction of the antigenic determinants has identified that the location of 181-786 bp of SjZFP1 (SjZFP1-1) contains most antigen sites. Therefore, this location was selected in the present study to prepare recombinant protein antigen rSjZFP1-1/His and construct the recombinant eukaryotic expression plasmid pcDNA-SjZFP1-1. In two independent trials, BALB/c mice were immunized with recombinant proteins and challenged with Schistosoma japonicum. Average worms and liver eggs from vaccinated and control mice were counted to evaluate protection. The immunized mice developed high titers of antibodies. However, no significant differences in average worms and liver eggs were found between vaccination groups (rSjZFP1-1/His or pcDNA-SjZFP1-1+rSjZFP1-1/His) and non-vaccinated controls. Further study is proposed to focus on N-terminal peptides of SjZFP1.