Ⅲ型脊髓灰质炎病毒感染转基因小鼠的研究

目的验证ＰＶＲＴｇ２１转基因小鼠是否可作为脊髓灰质炎病毒的动物模型。方法应用３个不同毒力的Ⅲ型脊髓灰质炎病毒株（Ｓａｂｉｎ－３,Ｖａｃｃｉｎｅ３２１和Ｌｅｏｎ株）对能编码脊髓灰质炎病毒受体基因的转基因小鼠（ＰＶＲＴｇ２１）进行感染性实验。结果经脊髓接种,均可引起临床麻痹和神经细胞的特异性损伤。其表现随毒力的不同而不同,３个毒株的小鼠半数致麻痹剂量（ＰＤ５０）分别为１０￣１．１,１０￣２．６和１０￣４．９７ＴＣＩＤ＿５０,接种不同病毒引起的中枢神经系统组织学损伤也有明显的差别。结论ＰＶＲＴｇ２１转基因小鼠有可能成为评价脊髓灰质炎病毒和疫苗的神经毒力,研究病毒的变异和实施流行病监视的一种有用的动物模型。

The observation on infection of trasgenic mice (PVR Tg21) with polioviruses type 3

OBJECTIVE: To test and verify whether PVR Tg21 transgenic mice can be used as an animal model or not. METHODS: PVR Tg21 transgenic mice were infected with 3 poliovirus strains with different neurovirulence intraspinally. RESULTS: All the mice showed clinical paralysis with characteristic lesions in neurons. The symptoms varied with different potency of virus. The onset of clinical paralysis time for inoculated mice were approximately 2 days with Leon virus, 5 days with Sabin strain, and 4 days with Vaccine-321. More than 90% of mice inoculated with Leon strain died within 3 days after clinical paralysis and only 35% mice inoculated with Sabin-3 died at average of 6 days, and the PD50 are 10(1.1), 10(2.6), and 10(4.97) TCID50 and LD50 are 10(1.1), 10(3.33) and 10(5.33) TCID50, respectively. Different virus inoculated intraspinally caused different histopathological lesions. CONCLUSIONS: The PVR Tg21 transgenic mice could be a new animal model for neurovirulent evaluation of poliovaccines and epidemiological surveillance.