【摘要】 新城疫病毒(NDV)的HN蛋白是一个多功能蛋白,具有血凝素(HA)和神经氨酸酶(NA)两种活性,在病毒感染过程中扮演重要角色。本研究利用反向遗传操作技术,将NDV强毒株F48E9的HN基因替换弱毒株rLaSota的HN基因,获得嵌合病毒rL-F48E9HN。收获病毒尿囊液,提取基因组RNA,进行序列分析,结果显示嵌合病毒基因组的HN基因获得了正确替换。嵌合病毒在鸡胚内的生长特性与亲本株LaSota一致,与F48E9的生长特性相差甚远。嵌合病毒红细胞吸附性明显增强,较rLaSota株增加51%,而细胞融合作用无明显变化。rL-F48E9HN的鸡胚平均致死时间(MDT)为148 h,脑内致病指数(ICPI)为0.43,静脉接种致病指数(IVPI)为0,说明rL-F48E9HN的毒力仍然属于弱毒力范围,而没有达到中等毒力或者强毒力。更多还原

【Abstract】 The hemagglutinin-neuraminidase(HN) protein of Newcastle disease virus(NDV) plays a crucial role in the process of infection.In this study,we exchanged the HN gene of the velogenic strain by means of reverse genetics procedures.The HN gene of the attenuated recombinant NDV strain rLaSota was replaced by the HN gene of the virulent strain F48E9 to obtain the chimeric virus rL-F48E9HN.The allantoic fluid from the embryonated chicken eggs infected with the rescued virus rL-F48E9HN was harvested.Sequence analysis of viral genomic RNA showed that the HN gene in the genome of chimeric virus was correctly replaced.Growth characteristics of the chimeric virus in embryonated specific-pathogen-free(SPF) chicken eggs were consistent with the parent strain rLaSota,but far from F48E9.Chimeric virus increased by 51% in hemadsorption activity,compared with rLaSota strains,while no significant change occurred in cell fusion.The embryo mean death time(MDT) of rL-F48E9HN is 148 h,the intracerebral pathogenicity index(ICPI) is 0.43,and the intravenous pathogenicity index(IVPI) is 0.It suggested the chimeric virus rL-F48E9HN still belonged to the attenuated strain,not moderately or highly virulent strain.更多还原