羊败血性链球菌病灭活疫苗效力检验小鼠免疫攻毒法研究

Research on the Efficacy Test of Inactivated Vaccines against Sheep Septicemic Streptococcal Disease Using Mouse Immunochallenge

为解决羊败血性链球菌病灭活疫苗现行规程中效力检验采用靶动物免疫攻毒法所存在的动物筛选困难、动物质量不稳定、经济花费高等问题,开展了实验动物免疫攻毒替代方法研究。以靶动物免疫攻毒法为基础,确定该疫苗的最小保护剂量和不保护临界剂量,并在确认小鼠品系后开展平行关系研究,从而筛选出在小鼠模型上能够体现疫苗差异的最佳攻毒剂量。结果显示:合格疫苗1/2稀释度为最小免疫剂量,1/4稀释度为不符合规定的临界剂量;KM小鼠为替代方法最合适的小鼠品系;最佳攻毒剂量为使用2 MLD混合菌液,对免疫组和对照组进行攻毒,对照小鼠全部死亡,免疫小鼠至少保护70%。本研究建立了羊败血性链球菌病灭活疫苗效力检验实验动物免疫攻毒替代方法,这将有助于提升该类疫苗效力检验的稳定性和可靠性,为羊败血性链球菌病防控提供有力支撑。

In order to solve the difficulties in animal screening,unstable animal quality,high economic costs and other problems in the efficacy test of inactivated vaccines against sheep septicemic streptococcal disease using target animal immunochallenge,a research on the alternative methods of immunochallenge in experimental animals was conducted.Based on target animal immunochallenge,the minimum protective dose and non-protective critical dose of the vaccine were determined,and a parallel research was conducted after confirming the variety of mice to select the optimal dose that could reflect the difference of the vaccine in the mouse model.The results showed that,for qualified vaccines,1/2 dilution was the minimum immune dose,and 1/4 was the critical dose in noncompliance of regulations;KM mice were the most suitable alternatives;2MLD mixture of bacterial solution was used as the optimal dose to challenge the immune group and control group,all the mice in the control group died,and at least 70%of those in the immune group were protected.An alternative method of efficacy test of inactivated vaccines against sheep septicemic streptococcal disease using mouse immunochallenge was established by the study,which will improve the stability and reliability of the efficacy test of such vaccines,and support the prevention and control of sheep septicemic streptococcal disease.