ABSTRACT: The major antigenic protein of infectious hematopoietic necrosis virus (IHNV) is the surface glycoprotein G, which contains neutralizing epitopes that induce the production of immune neutralizing antibodies. In this study, the IHNV G gene sequence was truncated according to bioinformatics principles and then recombinantly expressed via an E. coli expression system. We then assessed the specific antibody immunoglobin M (IgM) levels of rainbow trout immunized with recombinant truncated G protein (emulsified with Freund’s incomplete adjuvant), and showed that antibody IgM levels of immunized fish were significantly higher than in the control group (p < 0.01). The mRNA expression levels of interferon 1 (IFN1) and interleukin-8 (IL-8) were also up-regulated significantly (p < 0.01) in head kidneys and spleens of rainbow trout immunized with recombinant truncated G protein. Also, after challenge with wild-type IHNV HLJ-09 virus on Day 28, rainbow trout immunized with recombinant truncated G protein showed cumulative survival rates of 60%. These results indicate that the truncated G protein of IHNV expressed by the E. coli prokaryotic expression system can be used as a candidate immunogen for an IHNV subunit vaccine, which lays a theoretical foundation for the study of further potential IHNV subunit vaccines.

中文翻译：

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传染性造血坏死病毒截断了G蛋白对虹鳟鱼的存活，免疫反应和抗病性的作用。

摘要：传染性造血坏死病毒（IHNV）的主要抗原蛋白是表面糖蛋白G，它含有中和表位，可诱导产生免疫中和抗体。在这项研究中，根据生物信息学原理将IHNV G基因序列截短，然后通过大肠杆菌重组表达表达系统。然后，我们评估了用重组截短的G蛋白（用弗氏不完全佐剂乳化）免疫的虹鳟鱼的特异性抗体免疫球蛋白M（IgM）水平，并显示免疫鱼的抗体IgM水平显着高于对照组（p <0.01 ）。在用重组截短的G蛋白免疫的虹鳟鱼的头部肾脏和脾脏中，干扰素1（IFN1）和白介素8（IL-8）的mRNA表达水平也显着上调（p <0.01）。同样，在第28天用野生型IHNV HLJ-09病毒攻击后，用重组截短的G蛋白免疫的虹鳟鱼的累积存活率达60％。这些结果表明大肠杆菌表达的IHNV的截短的G蛋白 原核表达系统可用作IHNV亚单位疫苗的候选免疫原，为进一步研究潜在的IHNV亚单位疫苗奠定了理论基础。