[Soluble expression of A/H1N1 influenza virus HA with Drosophila S2 cell line and its bio-activity identification].

Objective: To express soluble HA of A/H1N1 influenza virus in drosophila S2 cell line and identify its bio-activity.
Methods: HA gene was amplified from A/Shenzhen/71/09 virus strain using RT-PCR, then we constructed pAC5.1-HA expression vector, which was co-transfected into S2 cell with pCoblast vector. After transfection, stable S2 cell was selected through Blasticindin. HA in the supernatant was identified with Western Blot assay and purified with Ni-column. Recombinant HA was immunized into BALB/c mice 3 times, and the Abs titers were evaluated with ELISA.
Results: We successfully cloned HA gene with 1.7 x 10(3) bp of A/Shenzhen/71/09 virus strain and got recombinant pAC5. 1-HA expression vector. Stable S2 cell line was established after transfection and selection, which continuously expressed HA with molecular weight 75 x 10(3) D. After immunization with HA, the Abs titers were 1:1280 and 1: 5120 respectively on 10 d, 30 d.
Conclusion: We expressed soluble HA with good bio-activity, which contributed to research on immune diagnosis, subunit vaccine, and monoclonal Abs for influenza.