Li Xiao-liang, Shuai Jiang-bing, Fang Wei-huan
Institute of Preventive Veterinary Medicine and Zhejiang Provincial Key Laboratory of Preventive Veterinary Medicine, Zhejiang University, Hangzhou 310029, China.
J Zhejiang Univ Sci B. 2006 Nov;7(11):922-8. doi: 10.1631/jzus.2006.B0922.
Specific immunoglobulin (IgY) from egg yolk against Aeromonas hydrophila was produced by immunization of White Leghorn hens with formalin-killed whole cells of A. hydrophila. ELISA test using A. hydrophila as the coating antigen revealed that the specific antibody titer started to increase in the egg yolk at the 13th day post-immunization (P/N=2.18), reached the peak at the 56th day (P/N=13.82), and remained at high level until day 133 (P/N=7.03). The antibody was purified by saturated ammonium sulphate with a recovery rate of 63.5%. The specific IgY inhibited the growth of A. hydrophila at a concentration of 1.0 mg/ml during the 18 h incubation. Pre-treatment of polyploid gibel carps Carassius auratus Gibelio with specific IgY had a protection rate of 60% (6/10) against challenge with A. hydrophila, while none of the fishes in the control groups receiving sterile phosphate buffered saline (PBS) or non-specific IgY survived the challenge. Treatment of fishes with the specific IgY 4 h after the challenge also had lower mortality (70%, 7/10), a 30% reduction against the control PBS or non-specific IgY groups (10/10). These results indicate that specific IgY antibodies could be obtained easily from hens immunized with an inactivated A. hydrophila and could provide a novel alternative approach to control of diseases in fishes caused by this organism.
用嗜水气单胞菌福尔马林灭活全细胞免疫白来航鸡，制备了针对嗜水气单胞菌的特异性蛋黄免疫球蛋白（IgY）。以嗜水气单胞菌为包被抗原的ELISA试验表明，免疫后第13天蛋黄中的特异性抗体效价开始升高（P/N = 2.18），第56天达到峰值（P/N = 13.82），并一直保持在高水平直至第133天（P/N = 7.03）。用饱和硫酸铵纯化抗体，回收率为63.5%。特异性IgY在1.0 mg/ml浓度下孵育18 h可抑制嗜水气单胞菌生长。用特异性IgY预处理多倍体银鲫，对嗜水气单胞菌攻击的保护率为60%（6/10），而接受无菌磷酸盐缓冲盐水（PBS）或非特异性IgY的对照组鱼在攻击后无一存活。在攻击后4 h用特异性IgY处理鱼，死亡率也较低（70%，7/10），比对照组PBS或非特异性IgY组（10/10）降低了30%。这些结果表明，用灭活的嗜水气单胞菌免疫母鸡可轻松获得特异性IgY抗体，可为控制该病原菌引起的鱼类疾病提供一种新的替代方法。
