Zhang Ye, Wen Le-ying, Wang Min, Guo Jun-feng, Li Zi, Guo Yuan-ji
Institute of Virology, Chinese Academy of Preventive Medicine, Beijing 100052, China.
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi. 2003 Mar;17(1):15-7.
To understand the antigenic and genetic characteristics of Victoria like strain of influenza B virus isolated recently and to provide a scientific evidence for influenza surveillance and monitoring of influenza epidemic in future.
Viruses were passed in embryonated hen eggs and virion RNA was extracted from allantoic fluid and reverse transcribed to synthesize cDNA. cDNA was amplified by PCR and the PCR product was purified with a purification kit. Afterwards RNA sequence analysis was performed by dideoxynucleotide chain termination and a cloning method. Finally, phylogenetic analysis of the sequencing data was performed with MegAlign.
B/Sichuan/63/2001 and B/Zhejiang/2/2001 viruses were antigenically different from B/Shandong/7/97 strain. The substitution of nucleotide sequences of HA1genes of them compared with those of B/Shandong/7/97strain resulted in the change of amino acid sequences in antigenic determinants on HA1 protein domain. The phylogenetic analysis also indicated that strains isolated recently were genetically different from B/Shandong/7/97/strain. However, there was neither differences on the antigenicity nor genetic partern between these two isotates.
The antigenic drift of Victoria-like strain of influenza B virus isolated recently in China has further occurred.
了解近期分离的乙型流感病毒维多利亚系毒株的抗原性和基因特征，为今后流感监测及流感疫情监测提供科学依据。
病毒在鸡胚中传代，从尿囊液中提取病毒粒子RNA并反转录合成cDNA。通过PCR扩增cDNA，并用纯化试剂盒纯化PCR产物。之后采用双脱氧核苷酸链终止法和克隆方法进行RNA序列分析。最后用MegAlign对测序数据进行系统发育分析。
B/四川/63/2001和B/浙江/2/2001病毒与B/山东/7/97毒株抗原性不同。它们的HA1基因核苷酸序列与B/山东/7/97毒株相比发生了替换，导致HA1蛋白结构域抗原决定簇氨基酸序列发生改变。系统发育分析也表明，近期分离的毒株与B/山东/7/97毒株在基因上不同。然而，这两个毒株之间在抗原性和基因模式上均无差异。
我国近期分离的乙型流感病毒维多利亚系毒株进一步发生了抗原漂移。
