副链球菌,革兰氏阳性球菌,导致养殖鱼类的细菌性疾病。最近在韩国水产养殖场中副产气链球菌感染的增加证明了疫苗开发对预防这种疾病的重要性。在这项研究中,我们评估了由重组M样蛋白(SimA)和纤维蛋白原结合蛋白(FBP)候选物与氢氧化铝佐剂制备的亚单位疫苗对抗橄榄比目鱼ParalichthysolivaceusPararuberis感染的效果.对于体内实验,鱼(平均长度,7.18厘米;平均体重,3.5g)腹膜内注射:磷酸盐缓冲盐水(PBS,组1),PBS/氢氧化铝(第2组),FBP/氢氧化铝(第3组),SimA/氢氧化铝(第4组),和SimA/FBP/氢氧化铝(第5组)。3周后,使用PBS(第1组和第2组)对每组中的鱼进行增强,FBP(第3组),西玛(第4组),和没有佐剂的SimA/FBP(组5)。我们发现,在第2、3、4和5组中,鱼的相对存活率为6.25%,18.75%,50%,和12.5%,分别,而第1组的死亡率为80%,分别。我们做了蛋白质印迹,ELISA,和定量实时RT-PCR(qRT-PCR)后,以研究疫苗的进一步功效。免疫接种鱼血清的Western印迹和ELISA证实了针对SimA和FBP的特异性抗体的产生。此外,qRT-PCR结果表明,与FBP或对照组相比,重组蛋白SimA诱导了显着的特异性抗体反应,并增加了各种免疫反应相关基因的表达,包括白细胞介素-8(IL-8),toll样受体2(TLR2),肿瘤坏死因子-α(TNF-α),CD4-1和MHCII。因此,这些结果表明,SiMA是一种有效的疫苗候选物,可用于预防副金黄色葡萄球菌感染.
Streptococcus parauberis, a gram-positive cocci, causes bacterial disease in farmed fish. The recent increase in S. parauberis infection in aquatic farms in South Korea has justified the importance of vaccine development for the prevention of this disease. In this study, we evaluated the effect of subunit vaccines prepared from recombinant M-like protein (SimA) and fibrinogen-binding protein (FBP) candidates with an aluminum hydroxide adjuvant against S. parauberis infection in olive flounder Paralichthys olivaceus. For the in vivo experiment, fish (average length, 7.18 cm; average weight, 3.5 g) were injected intraperitoneally with: phosphate buffer saline (PBS, group 1), PBS/aluminum hydroxide (group 2), FBP/aluminum hydroxide (group 3), SimA/aluminum hydroxide (group 4), and SimA/FBP/aluminum hydroxide (group 5). After 3 weeks, the fish in each group were boosted using PBS (group 1 and 2), FBP (group 3), SimA (group 4), and SimA/FBP (group 5) without adjuvant. We found that the relative percent survival of fish after S. parauberis exposure in group 2, 3, 4, and 5 was 6.25%, 18.75%, 50%, and 12.5%, respectively, whereas the mortality in groups 1 was 80%, respectively. We performed Western blot, ELISA, and quantitative real time RT-PCR (qRT-PCR) after vaccination to investigate the further efficacy of the vaccine. Western blot and ELISA of vaccinated fish serum confirmed the production of specific antibodies against SimA and FBP. Furthermore, results of qRT-PCR showed that recombinant protein SimA induced a remarkably specific-antibody response compared with that in FBP or control and increased the expression of various immune response-related genes including interleukin-8 (IL-8), toll-like receptor 2 (TLR2), tumor necrosis factor-α (TNF-α), CD4-1, and MHC II. Thus, these results indicate that SimA is a potent vaccine candidate for protection against S. parauberis infection.