Expression of Nipah virus structural proteins F1 and G and preparation of hyperimmune antisera against two proteins

Abstract:

The fusion protein (F) and attachment glycoprotein (G) of Nipah virus (NiV) are important for the virus to infect cells and induce protective immunity. In this study, the NiV F1 and G gene fragments without the sequences of signal peptide and transmembrane domain were amplified by PCR, then cloned into E.coli expression vector pGEX-6P-1 and modified baculovirus vector, respectively. After induction by IPTG, NiV F1 and G proteins were efficiently expressed in E.coli when analyzed by SDS-PAGE, both showing good reactivity with the rabbit antiserum anti-NiV serum in Western blot. The expression of NiV F1 and G in baculovirus system were also detected by indirect immunofluorescent assay (IFA) of fixed Sf9 cells monolayer infected with the recombinant baculoviruses expressing F1 and G. Furthermore the anti-F1 and anti-G hyperimmune sera were prepared by immunization of rabbits respectively with purified E.coli-expressed F1 and G proteins. Western blot and IFA as well as ELISA showed that antisera against both protein had high titers with good reactivity and specificity. The present study has provided a base for development of diagnostic reagents for detection of NiV infection.

Key words:Nipah virus（NiV）; fusion protein; attachment glycoprotein; hyperimmune serum