中文摘要：

A/Duck/Guangxi/53/02（DKGX）是从我国南方健康鸭体内分离到的H5N1亚型禽流感病毒,该病毒对鸡具有高致病性,而且能感染哺乳动物模型Balb/c小鼠,但不致死小鼠（MLD50〉10^6.5）。本试验根据GenBank上的序列DKGX/53/02设计了8对引物,建立了对DKGX的8质粒反向遗传操作系统,并通过细胞转染技术成功拯救了R-DKGX。R-DKGX在对哺乳动物模型Balb/c小鼠的致病性方面保持了与亲本野生毒（W-DKGX,MLD50〉10^6.5）一致的生物学特性,即106EID50鼻腔感染小鼠后3 d均只能在肺脏检测到病毒,病毒含量分别为（3.22±0.51）lgEID50/mL和（3.69±0.88）lgEID50/mL,MLD50〉10^6.5。

英文摘要：

A/Duck/Guangxi/53/02 is a H5N1 subtype avian influenza virus isolated in health ducks from South China,which was highly pathogenic to chickens. In our study,an eight-plasmid infectious clone system was established and the reassortant virus was rescued from cell transfection. The rescued virus（R-DKGX） maintained the same biological properties as the wild virus （W-DKGX）. Both of the viruses could be recovered from the lungs of Balb/c mice 3 days after being inoculated intranasally with 106 EIDs0. The virus titers was （3.22 ± 0.51 ） lgEID50/mL and （3.69±0.88） lgEID50/mL respectively. The successful establishment of the infectious clone system of DKGX will play an important role in the studies of the molecular basis of the evolution and the relationship between the structure and function of H5N1 subtype avian influenza viruses.