Faculty of Biosciences, Fisheries and Economics, Norwegian College of Fishery Science, University of Tromsø, Tromsø N-9037, Norway.
Vaccine. 2011 Oct 13;29(44):7678-87. doi: 10.1016/j.vaccine.2011.07.138. Epub 2011 Aug 16.
Many viral vaccines used in aquaculture are unable to stimulate an appropriate level of immunity to withstand infection. By targeting specific components of the immune system it may be possible to trigger stronger, more effective responses to antigens. Flagellin has the ability to stimulate both the soluble and membrane-bound forms of toll-like receptor 5 (TLR5) in salmon leading to a proinflammatory response and activation of both the innate and adaptive immune system. In this study flagellin (FlaD from Vibrio anguillarum) was recombinantly produced in two forms, full-length (FDL) and a truncated form (FDS) with portions of the N- and C-termini removed to prevent polymerization. FDS was used to produce an antibody that was able to bind both forms of flagellin in immunoblot analysis. In cell culture using COS-7 cells, FDL was shown to stimulate the NF-κB pathway more effectively than FDS. Both forms of flagellin were used as an adjuvant with the antigen LPH (Hemocyanin from Limulus polyphemus hemolymph) in an immunization dose-response study. FDS and FDL stimulated the innate immune system of salmon inducing proinflammatory effects on days 2, 4 and 7 and the gene expression of important cytokines such as TNFα, IL-6, IL-8, and IL-1β were significantly up-regulated (p<0.05) in the spleen. TLR5S was more highly up-regulated than TLR5M indicating that the soluble form of TLR5 may play an important role in the innate immune response in salmon. ELISA analysis showed that the use of flagellin as an adjuvant with LPH was not able to significantly induce flagellin or LPH antibodies. This study shows that flagellin has the potential to be a highly effective adjuvant for salmon immunization, but further research is needed.
许多用于水产养殖的病毒疫苗都无法刺激出足够水平的免疫能力来抵御感染。通过针对免疫系统的特定成分，有可能引发更强烈、更有效的抗原反应。鞭毛蛋白具有刺激鲑鱼中可溶性和膜结合形式的 toll 样受体 5（TLR5）的能力，导致炎症反应和先天免疫和适应性免疫系统的激活。在这项研究中，鞭毛蛋白（来自鳗弧菌的 FlaD）以两种形式在两种形式中重组产生，全长（FDL）和截短形式（FDS），去除了 N-和 C-末端的部分以防止聚合。FDS 用于产生能够在免疫印迹分析中结合两种形式鞭毛蛋白的抗体。在使用 COS-7 细胞的细胞培养中，FDL 被证明比 FDS 更有效地刺激 NF-κB 途径。两种形式的鞭毛蛋白均用作抗原 LPH（来自 Limulus polyphemus 血淋巴的血蓝蛋白）的佐剂，在免疫剂量反应研究中。FDS 和 FDL 刺激鲑鱼的先天免疫系统，在第 2、4 和 7 天引起炎症反应，并显著上调重要细胞因子如 TNFα、IL-6、IL-8 和 IL-1β 的基因表达（p<0.05）在脾脏中。TLR5S 的上调幅度高于 TLR5M，表明可溶性 TLR5 可能在鲑鱼的先天免疫反应中发挥重要作用。ELISA 分析表明，鞭毛蛋白作为 LPH 的佐剂的使用不能显著诱导鞭毛蛋白或 LPH 抗体。这项研究表明，鞭毛蛋白有可能成为鲑鱼免疫接种的高效佐剂，但需要进一步研究。
