大流行甲型H1N1流感病毒变异株的小鼠感染实验研究

Experimental infection of a variant pandemic H1N1 influenza A virus in BALB/c mice

目的对甲型H1N1流感病毒变异株的小鼠感染特征进行观察。方法经过体外鸡胚/MDCK细胞传代和筛选,获得1株甲型H1N1流感病毒变异株(vCA07);使用不同剂量流感病毒滴鼻感染BALB/c小鼠后,计算半数致死量和半数感染量,观察小鼠感染后的体质量变化、肺部病毒增殖、肺部组织病理变化等。结果与野生型毒株相比,甲型H1N1流感病毒变异株对BALB/c小鼠的致病性显著提高,其可在小鼠肺组织中高效增殖,并导致显著的病理损伤。结论甲型H1N1流感病毒变异株感染特征得以明确,为进一步建立高致病性甲型H1N1流感病毒的小鼠感染模型以及大流行甲型H1N1流感病毒致病机制的研究奠定了基础。

Objective To characterize the manifestations in mice infected with a variant strain of the pandemic H1N1 influenza A virus. Methods A variant of H1N1 influenza virus was obtained by continuous passages in embryonated eggs and MDCK cells. The mice were infected intratracheally with different doses of the variant H1N1 influenza A virus. The median lethal dose （MLDs0） and median infection dose （MID50） of the high virulent H1N1 variant in BALB/c mice were evaluated. The body weigh change, lung index and lung virus loads in the infected mice were also observed. Results The pathogenicity of the variant H1N1 influenza A virus in mice was significantly higher than that of the wild type. The lower infection dose, higher viral load and severe lesions in lung tissues were observed. Conclusion The characterization of the variant H1N1 virus influenza A infection in mice facilitates the development of a novel murine model of pandemic H1N1 influenza A virus.