Construction of the Eukariotic Expression Vector for s1 Gene Fragment of SARS-CoV and its Immunol ogical Effects

The 801 base pairs of S1 gene fragment were synthesized based on the Sever acute respiratory syndrome associated coronavirus(SARS-CoV)BJ01 strain registered in GenBank.The synthetical DNA was subcloned into the appropriate site of pcDNA3.1(+) eukariotic expression vector to construct a recombinant plasmid pcDNA3.1(+)/S1;The recombinant plasmid pcDNA3.1(+)/S1 was transfected into Hela cells and the expressed protein was identified by SDS-PAGE and Western-blotting;BALB/c mice were immunized with pcDNA3.1(+)/S1 by i.m.The level of anti-SARS-CoV IgG and IFN-γ in BALB/c mice after immunization were detected by ELISA and T cell proliferation activity was tested by MTT.It was found that the recombinant plasmid pcDNA3.1(+)/S1 could express S1 protein in Hela cells,T cell proliferative activity,the level of anti-SARS-CoV IgG and IFN-γ increased after immunization.It revealed that pcDNA3.1(+)/S1 could induce moderate cellular and humoral immunological reaction in BALB/c mice.