Severe acute respiratory syndrome (SARS) is an emerging infectious disease associated with a novel coronavirus and causing worldwide outbreaks. SARS coronavirus (SARS-CoV) is an enveloped RNA virus, which contains several structural proteins. Among these proteins, spike (S) protein is responsible for binding to specific cellular receptors and is a major antigenic determinant, which induces neutralizing antibody. In order to analyze the antigenicity and receptor-binding ability of SARS-CoV S protein, we expressed the S protein in Escherichia coli using a pET expression vector. After the isopropyl-β-D-thiogalactoside induction, S protein was expressed in the soluble form and was purified by nickel-affinity chromatography to homogeneity. The amount of S protein recovered was 0.2 to 0.3 mg per 100 ml bacterial culture. The S protein was recognized by sera from SARS patients by ELISA and Western blot, indicated that recombinant S protein remained its antigenicity. By biotinylated ELISA and Western blot using biotin-labeled S protein as the probe, we identified 130-kDa and 140-kDa proteins in Vero cells might be the cellular receptors responsible for SARS-CoV infection. Therefore, these results suggested that recombinant S protein exhibited the antigenicity and receptor-binding ability, and it could be a good candidate for further developing SARS vaccine and anti-SARS therapy.?
關聯:
The Nineteenth Joint Annual Conference of Biomedical Sciences
