Characterizaiton of virus-like particles prepared by Bac-to-Bac system co-expressing HA and M1 ;protein of highly pathogenic avian influenza H5N1 / 中华微生物学和免疫学杂志

ABSTRACT

Objective To express and characterize the virus-like particles( VLPs) of H5 subtype containing of hemagglutinin ( HA ) and matrix 1 ( M1 ) protein by using Baculovirus-insect cells .Methods Full length genes encoding HA protein from the A/Indonesia/05/2005(H5N1) strain and the M1 protein from the A/Anhui/01/2005 ( H5N1 ) strain were cloned into a baculovirus expression vector to construct pFBD-M1-HA.The expression of HA and M1 proteins were detected by Western blot and indirect immunoflu-orescence after the transfection of Spodoptra frugiperda (Sf9) insect cells with recombinant baculovirus.Pu-rified VLPs were analyzed by SDS-PAGE and visualized with transmission electron microscope.The biologi-cal activity of purified VLPs was detected by hemagglutination test.Results The HA and M1 proteins of H5 subtype expressed by baculovirus-insect cells could be self-assembled into the functional mature VLPs.The hemagglutination titer of VLPs was as high as 1024 HAU/50μl.Conclusion The H5 subtype VLPs as pre-pared in this study would pave a way for the development of a candidate recombinant A ( H5) vaccine.