Simian virus 40 (SV40) is a member of the Polyomaviridae family .Express the structural protein VP1 of SV40 in Bac-to-Bac baculovirus expression system. The expressed protein will be self-assembled to SV40 virus-like particles (SV40 VLPs). Then it will be extracted and purified by ultracentrifugation and molecular sieve. VP1 specified band could be observed at 46KDa in polyacrylamide gelelectrophoresis (SDS-PAGE). Indirect immunofluorescence assay (IFA)proved that VP1 VLPs combined with fluorescein isothiocyanate(FITC)-labeled goat anti-mouse antibody to present green fluorescence. This indicated VP1 protein had good antigenicity. The purified VLPs could be observed under electron microscope with 45nm diameter, which indicated SV40 VLPs was successfully assembled. The Western-blot showed SV40 VLPs could react with human-derived anti-SV40 plasma, which also indicated VLPs had good antigenicity.
