斑点叉尾鮰源嗜麦芽寡养单胞菌的脂质体疫苗研究  

Liposome-encapsulated bacterial antigen against Stenotrophomonas maltophilia infection in channel catfish (Ictalurus punctatus)

作　　者：汪开毓[1] 邓龙君[2] 肖丹 耿毅[1] 黄小丽[2] 陈德芳[1] 

机构地区：[1]四川农业大学动物医学院鱼病研究中心,四川雅安625014 [2]四川农业大学动物科技学院水产系,四川雅安625014 [3]通威股份有限公司,四川成都610041

出　　处：《中国水产科学》2009年第5期751-757,共7页Journal of Fishery Sciences of China

基　　金：教育部"长江学者和创新团队发展计划"创新团队项目(IRT0848);农业部动物检疫检测与防治项目(2130108);通威股份有限公司重点资助项目(2006-2009)

摘　　要：采用反相蒸发法制备嗜麦芽寡养单胞菌的脂质体疫苗,通过灌胃分别给予各组斑点叉尾鮰(Ictalurus punctatus)脂质体疫苗(Ⅰ-Ⅲ组)、嗜麦芽寡养单胞菌灭活苗(Ⅳ组)和生理盐水(Ⅴ组),每2周给药1次,共3次。于接种疫苗后第1天、14天、28天和第49天采集静脉血,测定白细胞的杀菌活性和血清抗体IgM含量的变化,并用细菌攻毒实验检测免疫保护效应。结果显示,本实验制备的脂质体疫苗粒径约为(0.9±0.3)μm,包封率为53.23%,与嗜麦芽寡养单胞菌灭活苗相比能显著增强斑点叉尾鮰吞噬细胞的杀菌活性和血清抗体IgM水平。腹腔注射活菌攻毒后,脂质体疫苗免疫的Ⅰ-Ⅲ组的相对免疫保护率分别为34.8%、48.2%和55.4%;而嗜麦芽寡养单胞菌灭活苗免疫的Ⅳ组的相对免疫保护率仅有6.7%,生理盐水对照Ⅴ组保护率则为零。研究表明,口服脂质体疫苗对斑点叉尾鮰具有显著的免疫保护效应,可作为预防嗜麦芽寡养单胞菌感染的疫苗。Liposome-encapsulated Stenotrophomonas maltophilia antigen was prepared by using reverse-phase evaporation method to investigate its potential protective efficacy for S. maltophilia infection. Channel catfish（ Ictalurus punctatus） were devided into five treatment groups：Ⅰ-Ⅲ group were immunized orally with liposome-encapsulated S. maltophilia antigen at the dosage of 50 μg/ind,100 μg/ind and 200 μg/ind. Ⅳ group was immunized orally with inactived S. maltophilia antigen alone. And Ⅴ group was set as control by giving equivalent water. Vaccination was carried out 3 times at 2-week intervals.On day 1,14,28 and 49, bactericidal activity of leukocytes and content of IgM in serum were detected periodically to investigate cellular and humoral immune effects. On day 63, all fish were challenged with alive S. maltophilia （1 ×10^8CFU/mL） by injection to estimate the protective efficacy. The liposome-encapsulated S. maltophilia antigen was successfully obtained, with mean size of （0.9±0.3）μm. After immunization, hposome-encapsulated S. maltophilia antigen trigered significantly higher bactericidal activity and serum antibody level compared with S. maltophilia alone （P〈0.05）. After challenge with S. maltophilia, the relative survival rates of Ⅰ, Ⅱ, Ⅲ group, which had received different dosage of liposome-encapsulated S. maltophilia antigen, were 34.8%,48.2%,55.4%, respectively. In contrast, the relative survival rate of Ⅳ group which had received antigen of inactivated S. maltophilia was merely 6.7%, and the survival rate of the control group （Ⅴ group） was even 0. These results suggest that liposome-encapsulated S. maltophilia antigen has the potential for inducing protective immune response against atypical S. maltophilia infection and also suggest the possibility of developing a vaccine that may ultimately be used for fish disease prevention. [Journal of Fishery Sciences of China,2009,16 （5）： 751-757]

关 键 词：斑点叉尾鮰 嗜麦芽寡养单胞菌 脂质体疫苗 

分 类 号：S94[农业科学—水产养殖]