Zhang Yilin, Ning Deyu, Nie Jiachun, Hou Xiaoyong, Li Wenze, Gan Zhen, Lu Yishan
Guangdong Provincial Engineering Research Center for Aquatic Animal Health Assessment, Shenzhen Public Service Platform for Evaluation of Marine Economic Animal Seedings, Shenzhen Institute of Guangdong Ocean University, Shenzhen, 518120, China; Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture, Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institute, College of Fishery, Guangdong Ocean University, Zhanjiang, 524088, China.
Guangdong Provincial Key Laboratory of Aquatic Animal Disease Control and Healthy Culture, Key Laboratory of Control for Disease of Aquatic Animals of Guangdong Higher Education Institute, College of Fishery, Guangdong Ocean University, Zhanjiang, 524088, China.
Fish Shellfish Immunol. 2025 Apr;159:110183. doi: 10.1016/j.fsi.2025.110183. Epub 2025 Feb 8.
The grouper farming industry was severely influenced by vibriosis. In this study, we developed two live-attenuated vaccine (LAV) candidates against Vibrio alginolyticus infection in pearl gentian groupers using cpxA or cpxR mutant strains of V. alginolyticus (ΔcpxA and ΔcpxR). Groupers were administrated with ΔcpxA and ΔcpxR at the dose of 1.0 × 10 CFU/fish (safety dose) to evaluate the immune protect effect of LAV. The increasing median lethal dose (LD) of ΔcpxA and ΔcpxR indicated the decreased virulence of bacteria to groupers. Our results suggested that two LAVs achieved over 70 % relative percent survival (RPS) after groupers were challenged by V. alginolyticus on 14 days post-immunization. The immune protection was mainly attributed to the up-regulation of immune-related gene expression (IL-6, IL-12, TNF-α, TLR2, TLR5S, CD4, MHC-Iα, IFN-γ2 and NF-κB), the higher activities of catalase (CAT), lysozyme (LZM), superoxide dismutase (SOD), and the increasing production of total protein (TP) in serum. The research indicated that the vaccination of fish with ΔcpxA and ΔcpxR can induce the innate and acquired immunity and survival rate of groupers after bacterial infection, so they can be considered as the promising candidates of vaccine for grouper industry.
石斑鱼养殖业受到弧菌病的严重影响。在本研究中，我们使用溶藻弧菌的cpxA或cpxR突变株（ΔcpxA和ΔcpxR）开发了两种针对珍珠龙胆石斑鱼溶藻弧菌感染的减毒活疫苗（LAV）候选疫苗。以1.0×10 CFU/鱼的剂量（安全剂量）给石斑鱼接种ΔcpxA和ΔcpxR，以评估LAV的免疫保护效果。ΔcpxA和ΔcpxR的半数致死剂量（LD）增加表明细菌对石斑鱼的毒力降低。我们的结果表明，在免疫后14天用溶藻弧菌攻击石斑鱼后，两种LAV的相对存活率（RPS）达到70%以上。免疫保护主要归因于免疫相关基因表达（IL-6、IL-12、TNF-α、TLR2、TLR5S、CD4、MHC-Iα、IFN-γ2和NF-κB）的上调、过氧化氢酶（CAT）、溶菌酶（LZM）、超氧化物歧化酶（SOD）的较高活性以及血清中总蛋白（TP）产量的增加。研究表明，用ΔcpxA和ΔcpxR对鱼进行疫苗接种可以诱导石斑鱼在细菌感染后的先天免疫和获得性免疫以及存活率，因此它们可被视为石斑鱼养殖业有前景的疫苗候选物。
