应用BALB/c小鼠评价口蹄疫灭活疫苗的免疫效力

用不同剂量的口蹄疫灭活疫苗免疫3组雌性BALB/c小鼠,同时设空白对照组,每组8只。免疫后每7 d采血一次,用液相阻断ELISA(LPB-ELISA)检测血清抗体水平;第28 d用800LD50同源强毒攻击,攻毒后36 h,每组随机选取3只BALB/c小鼠,采全血,分别用每只BALB/c小鼠全血注射12只乳鼠,每组共注射36只乳鼠,以乳鼠试验判定BALB/c小鼠的病毒血症和攻毒保护情况。结果表明,免疫组BALB/c小鼠均可产生特异性抗体,保护率分别为75.0%、63.9%、36.1%;对照组小鼠血清抗体为阴性。提示,BALB/c小鼠可以用来评价口蹄疫灭活疫苗的免疫效力。

Evaluation of efficacy of inactivated vaccine against foot-and-mouth disease in BALB/c mice

Thirty-two adult female BALB/c mice,8 per group,were immunized with different doses of the inactivated foot-and-mouth disease(FMD) type O vaccine and the control group was set.Whole blood of all the mice were collected on day 7,14,21 and 28 post-immunization and FMDV-specific neutralizing antibody(NAb) levels were examined by liquid-phase blocking sandwich ELISA(LPB-ELISA).On day 28,all the mice were challenged with 800 LD50 of the prevalent FMDV from the same origin.Whole blood from 3 mice in each group were collected at hour 36 post-infection and injected into 36 sucking mice totally to assess protection in the BALB/c mice.In results,FMDV-specific NAb was found in the immunized mice.The protection rates for the mice in the three experimental groups were 75.0%,63.9% and 36.1%,respectively.The mice in the control group had no FMDV-specific NAb response to the vaccine.The results revealed that BALB/c mice could be used to evaluate efficacy of inactivated vaccines against FMD.