犬副流感弱毒株的分离与鉴定

Isolation and identification of canine parainfluenza attenuated vaccine strain

目的 分离并鉴定犬副流感弱毒株 ,供疫苗制备 .方法 根据犬副流感的血球吸附特性、细胞培养特性以及异种病毒抗血清阻断法分离病毒 (简称为 CPIV- XN4病毒 ) .并对其进行形态学、生物学特性等系统鉴定 .结果 病毒分离后其毒力可达 10 - 6 TCID5 0 .在电镜下可见较典型的犬副流感病毒形态结构特征 ;免疫电镜下见到抗体分子已被吸附在病毒颗粒表面 ;在几种细胞上盲传结果 MDCK和 Vero细胞出现程度不同的病变 (CPE) ;血清中和抗体效价 (SN)可达149.6 2 ;CPIV- XN4与国际标准毒株 D- 0 0 8之间有交叉中和反应 ;病毒接种到健康幼犬后 15 d内未发现仔犬死亡 ;攻毒实验结果 ,对照组有 2条在攻毒后 9d出现神经症状 ,第 14日衰竭而死 ,实验组动物均未出现临床症状 .结论 CPIV-

AIM To produce the vaccine, we isolated a strain of canine parainfluenza attenuated virus. METHODS According to the cellular adsorptive and cultural properties of the canine parainfluenza virus, we isolated the virus named CPIV XN 4,by heterovirus anti serum blocking test. We alsoidentified its morphological and biological characteristics. RESULTS The titer of the virus was 10 -6 TCID 50 . There could be seen the typical canine parainfluenza virus particles under the electron microscope. The antibody molecules had been absorbed in the surface of the virus particle, which was observed under the immuno electron microscope. The neutralized antibody titer was 149.62; CPIV XN 4 had a cross neutralized reaction with the international standard strain. There were no deaths 15 days after incobulation in health infant dogs. The attack results showed that two dogs of the control group had nerve symptoms on the 9th day and died 14 days later. No dogs showed any clinical symptoms in the experiment group. CONCLUSION CPIV XN 4 could be a candidate for vaccine strain.