Han Yanhui, Zhang Min, Hong Yang, Zhu Zhu, Li Dong, Li Xiangrui, Fu Zhiqiang, Lin Jiaojiao
Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Animal Parasitology, Ministry of Agriculture of China, Shanghai 200241, PR China.
Parasitol Int. 2012 Sep;61(3):475-80. doi: 10.1016/j.parint.2012.03.005. Epub 2012 Mar 30.
Schistosomiasis is one of the most prevalent and serious parasitic diseases in the world and remains an important public health problem in China. Screening and discovery of an effective vaccine candidate or new drug target is crucial for the control of this disease. In this study, we cloned a cDNA encoding Schistosoma japonicum (S. japonicum) thioredoxin glutathione reductase (SjTGR) from the cDNA of 42-day-old adult worms. The open reading frame (ORF) of the gene was 1791 base pairs (bp) encoding a protein of 596 amino acids. SjTGR was subcloned into pET-32a (+) and expressed in Escherichia coli (E. coli) BL21 (DE3). The recombinant protein rSjTGR exhibited enzymatic activity of 5.13U/mg with DTNB as the substrate, and showed strong immunogenecity. Real-time PCR results indicated that SjTGR was expressed at a higher level in 35-day-old schistosome worms in transcript. We vaccinated BALB/c mice with rSjTGR in combination with MONTANIDE™ ISA 206 VG (ISA 206) and observed a 33.50% to 36.51% (P<0.01) decrease in the adult worm burden and a 33.73%to 43.44% (P<0.01) decrease in the number of eggs counted compared to the ISA 206 or blank control groups in two independent vaccination tests. ELISA analysis demonstrated that rSjTGR induced a high level of SjTGR-specific IgG, IgG1, and IgG 2a antibodies and induced elevated production of IFN-γ. This study provides the basis for further investigations into the biological function of SjTGR and further evaluation of the potential use of this molecule as a vaccine candidate or new drug target is warranted.
血吸虫病是世界上最普遍且严重的寄生虫病之一，在中国仍然是一个重要的公共卫生问题。筛选和发现有效的候选疫苗或新的药物靶点对于控制这种疾病至关重要。在本研究中，我们从42日龄成虫的cDNA中克隆了编码日本血吸虫硫氧还蛋白谷胱甘肽还原酶（SjTGR）的cDNA。该基因的开放阅读框（ORF）为1791个碱基对（bp），编码一个由596个氨基酸组成的蛋白质。将SjTGR亚克隆到pET-32a（+）中，并在大肠杆菌BL21（DE3）中表达。以5,5'-二硫代双（2-硝基苯甲酸）（DTNB）为底物时，重组蛋白rSjTGR表现出5.13U/mg的酶活性，并具有很强的免疫原性。实时PCR结果表明，SjTGR在转录水平上在35日龄血吸虫中表达较高。我们将rSjTGR与MONTANIDE™ ISA 206 VG（ISA 206）联合用于免疫BALB/c小鼠，在两项独立的免疫试验中，与ISA 206或空白对照组相比，观察到成虫负荷降低了33.50%至36.51%（P<0.01），计数的虫卵数量减少了33.73%至43.44%（P<0.01）。ELISA分析表明，rSjTGR诱导产生了高水平的SjTGR特异性IgG、IgG1和IgG 2a抗体，并诱导了γ干扰素（IFN-γ）产生增加。本研究为进一步研究SjTGR的生物学功能提供了基础，有必要进一步评估该分子作为候选疫苗或新药物靶点的潜在用途。
