Fisheries College of Jimei University/Engineering Research Center of the Modern Industry Technology for Eel. Ministry of Education of PR China, Xiamen, 361021, China; State Key Laboratory of Mariculture Breeding, Fisheries College of Jimei University, China.
Fisheries College of Jimei University/Engineering Research Center of the Modern Industry Technology for Eel. Ministry of Education of PR China, Xiamen, 361021, China; State Key Laboratory of Mariculture Breeding, Fisheries College of Jimei University, China.
Microb Pathog. 2024 Apr;189:106591. doi: 10.1016/j.micpath.2024.106591. Epub 2024 Feb 23.
The eel farming industry is highly susceptible to Vibriosis. Although various types of vaccines against Vibriosis have been investigated, there is limited research on decreasing the virulence of Vibrions through gene knockout and utilizing it as live attenuated vaccines (LAV). In this study, we aim to develop a LAV candidate against Vibrio harveyi infection in American eels (Anguilla rostrata) using a ferric uptake regulator (fur) gene mutant strain of V. harveyi (Δfur mutant). After the eels were administrated with the Δfur mutant at the dose of 4 × 10 cfu/g body weight, the phagocytic activity of the leucocytes, plasma IgM antibody titers, activity of lysozyme and Superoxide Dismutase (SOD) enzyme, and gene expression levels of 18 immune related proteins were detected to evaluate the protection effect of the LAV. Preliminary findings suggest that the LAV achieved over 60% relative percent survival (RPS) after the American eels were challenged by a wild-type strain of V. harveyi infection on 28 and 42 days post the immunization (dpi). The protection was mainly attributed to increased plasma IgM antibody titers, higher levels of lysozyme, enhanced activity of SOD and some regulated genes encoded immune related proteins. Together, the Δfur mutant strain of V. harveyi, as a novel LAV vaccine, demonstrates promising protective effects against V. harveyi infection in American eels, thus presenting a potential candidate vaccine for fish farming.
鳗鱼养殖业极易感染弧菌病。虽然已经研究了多种针对弧菌病的疫苗，但通过基因敲除降低弧菌毒力并将其用作活减毒疫苗（LAV）的研究有限。在这项研究中，我们旨在使用鳗弧菌（Vibrio harveyi）的铁摄取调节剂（fur）基因突变株（Δfur 突变株）开发针对美洲鳗（Anguilla rostrata）感染的 LAV 候选物。在以 4×10cfu/g 体重的剂量给鳗鱼施用 Δfur 突变株后，检测白细胞的吞噬活性、血浆 IgM 抗体滴度、溶菌酶和超氧化物歧化酶（SOD）酶的活性以及 18 种免疫相关蛋白的基因表达水平，以评估 LAV 的保护效果。初步结果表明，在免疫后 28 和 42 天，美洲鳗受到野生型鳗弧菌感染的挑战后，LAV 获得了超过 60%的相对存活率（RPS）。保护作用主要归因于血浆 IgM 抗体滴度的增加、溶菌酶水平的提高、SOD 活性的增强以及一些调节免疫相关蛋白的基因的表达。总之，作为一种新型 LAV 疫苗，鳗弧菌的 Δfur 突变株对美洲鳗感染弧菌表现出有希望的保护作用，因此是一种有潜力的鱼类养殖候选疫苗。
