Murakami Shin, Iwasa Ayaka, Iwatsuki-Horimoto Kiyoko, Ito Mutsumi, Kiso Maki, Kida Hiroshi, Takada Ayato, Nidom Chairul A, Mai Le Quynh, Yamada Shinya, Imai Hirotaka, Sakai-Tagawa Yuko, Kawaoka Yoshihiro, Horimoto Taisuke
Division of Virology, Department of Microbiology and Immunology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
Vaccine. 2008 Nov 25;26(50):6398-404. doi: 10.1016/j.vaccine.2008.08.053. Epub 2008 Sep 17.
H5N1 highly pathogenic avian influenza viruses evolved into several clades, leading to appreciably distinct antigenicities of their hemagglutinins. As such, candidate H5N1 pre-pandemic vaccines for human use should be sought. Here, to evaluate fundamental immunogenic variations between H5N1 vaccines, we prepared four inactivated H5N1 test vaccines from different phylogenetic clades (clade 1, 2.1, 2.2, and 2.3.4) in accordance with the WHO recommendation, and tested their cross-clade immunity in a mouse model by vaccination followed by challenge with heterologous virulent viruses. All H5N1 vaccines tested provided full or partial cross-clade protective immunity, except one clade 2.2-based vaccine, which did not protect mice from clade 2.3.4 virus challenge. Among the test vaccines, a clade 2.1-based vaccine possessed the broadest-spectrum cross-immunity. These results suggest that currently stockpiled pre-pandemic vaccines, especially clade 2.1-based vaccines, will likely be useful as backup vaccines in a pandemic situation, even one involving antigenic-drifted viruses.
H5N1高致病性禽流感病毒进化成了几个分支，导致其血凝素的抗原性明显不同。因此，应寻找供人类使用的H5N1大流行前候选疫苗。在此，为评估H5N1疫苗之间的基本免疫原性差异，我们按照世界卫生组织的建议，从不同系统发育分支（分支1、2.1、2.2和2.3.4）制备了四种灭活的H5N1试验疫苗，并通过接种疫苗然后用异源强毒病毒攻击，在小鼠模型中测试了它们的跨分支免疫性。除了一种基于2.2分支的疫苗不能保护小鼠免受2.3.4分支病毒攻击外，所有测试的H5N1疫苗都提供了完全或部分的跨分支保护性免疫。在试验疫苗中，一种基于2.1分支的疫苗具有最广谱的交叉免疫性。这些结果表明，目前储备的大流行前疫苗，尤其是基于2.1分支的疫苗，在大流行情况下可能会作为备用疫苗发挥作用，即使是在涉及抗原漂移病毒的大流行中。
