Development of adenoviral-vector-based pandemic influenza vaccine against antigenically distinct human H5N1 strains in mice

Lancet 2006; 367: 475-81

Speaker：Zhao-Hong Li              Time： 3/15  15:00~16:00

Commentator：Dr. Ai-Li Shiau         Place： Room 601

Abstract：

Highly pathogenic avian influenza virus strains (H5N1) are currently circulating around the world and have a devastating impact on wild birds and poultry. Influenza viruses are normally highly species-specific, but the H5N1 virus has crossed the species barrier to infect humans in recent years. This has raised concerns about the potential pandemic, like Spanish Flu in 1918. The available influenza vaccines currently can not protect hosts against H5N1 virus and most of vaccines are produced from embryonated eggs. However, the constant supply of embryonated eggs might be difficult in a pandemic. The authors developed an adenoviral-vector-based vaccine which is egg-independent. They used the Cre-recombinase-mediated site-specific recombination system to construct a replication-defective, recombinant human adenovirus vector expressing the H5 gene of avian H5N1 influenza virus (HAd-H5HA). They found that the vaccine induced both humoral and cellular immune responses in vaccinated BALB/c mice and increased HA-518-epitope-specific interferon-γ-secreting CD8 T cells by three to eight-fold when compared to a traditional subunit vaccine. The HAd-H5HA vaccine effectively prevented mice from disease and death. Meanwhile, the viral titers of lungs were dramatically decreased after immunization. These results suggest that the recombinant adenovirus-based vaccines may serve as a stockpiling option to control the ongoing influenza pandemic.

References：

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2.      Wentao Gao, Adam C. Soloff, Xiuhua Lu, et al. Protection of mice and poultry from lethal H5N1 avian influenza virus through adenovirus-based immunization. J Virol 2006; 80:1959-1964.