Matsuzaki Yoko, Sugawara Kanetsu, Takashita Emi, Muraki Yasushi, Hongo Seiji, Katsushima Noriko, Mizuta Katsumi, Nishimura Hidekazu
Department of Bacteriology, Yamagata University School of Medicine, Iida-Nishi, Yamagata, Japan.
J Med Virol. 2004 Sep;74(1):132-40. doi: 10.1002/jmv.20156.
To characterize the genetic diversity of influenza B viruses isolated during one influenza season, the antigenic and genetic relationships among 20 strains of influenza B virus isolated in February and March 2001 at one pediatric clinic in Yamagata City, Japan, were investigated. The HA gene and seven other gene segments were phylogenetically divided into three distinct sublineages (Harbin/7/94-, Tokyo/6/98-, and Shiga/T30/98-related lineage) of the Yamagata/16/88-like lineage. The NS genes of the viruses belonging to the Harbin/7/94-related lineage have additional three nucleotides at positions 439-447, and were phylogenetically distinguishable from those of the currently circulating Yamagata/16/88- and Victoria/2/87-like lineages, but were closely related to that of the Yamagata/16/88-like lineage isolated before 1994. Moreover, four strains of influenza B virus isolated in the same community between 2002 and 2003 were further examined. Phylogenetic analysis revealed that a virus of Victoria/2/87-like lineage isolated in 2003 had acquired the NA, NS, M, and PA gene segments from a Shiga/T30/98-like virus, and two strains of Harbin/7/94-related lineage had acquired the various gene segments from Shiga/T30/98-like virus through a reassortment event. These results indicate that genetically distinct multiple viruses can combine to cause an influenza B epidemic in a community and that the frequent reassortment among these viruses plays a role in generating the genetic diversity of influenza B viruses.
为了描述一个流感季节期间分离出的乙型流感病毒的基因多样性,我们调查了2001年2月和3月在日本山形市一家儿科诊所分离出的20株乙型流感病毒之间的抗原和基因关系。血凝素(HA)基因和其他七个基因片段在系统发育上被分为山形/16/88样谱系的三个不同亚谱系(哈尔滨/7/94相关谱系、东京/6/98相关谱系和滋贺/T30/98相关谱系)。属于哈尔滨/7/94相关谱系的病毒的非结构蛋白(NS)基因在439 - 447位有额外的三个核苷酸,在系统发育上与目前流行的山形/16/88样和维多利亚/2/87样谱系的病毒不同,但与1994年前分离出的山形/16/88样谱系的病毒密切相关。此外,对2002年至2003年在同一社区分离出的四株乙型流感病毒进行了进一步检测。系统发育分析显示,2003年分离出的一株维多利亚/2/87样谱系的病毒从一株滋贺/T30/98样病毒获得了神经氨酸酶(NA)、NS、基质蛋白(M)和聚合酶酸性蛋白(PA)基因片段,两株哈尔滨/7/94相关谱系的病毒通过重配事件从滋贺/T30/98样病毒获得了各种基因片段。这些结果表明,基因不同的多种病毒可以结合在一起在一个社区引发乙型流感流行,并且这些病毒之间频繁的重配在产生乙型流感病毒的基因多样性方面发挥了作用。