Expression and bioactivity analysis of staphylococcal enterotoxin C 2

Aim To clone the gene of staphylococcal enterotoxin C_(2) and express it in the form of a soluble fusion protein in E.coli.Then the activation of SEC_(2) on mice lymphocyte and its lethal effects on tumor cells were studied.Methods Staphylococcus aureus SEC_(2) gene was cloned into GST gene fusion vector pGEX-4T-1.The resultant plasmid pGEX-4T-SEC_(2) was used to transform E.coli BL21,where the GST-SEC_(2) fusion protein was expressed efficiently.The rSEC_(2) protein was purified with Glutathione Sepharose 4B affinity column and digested with thrombin.The in vitro culture system was utilized to observe the activation of the SEC_(2) on mice lymphocyte and the lethal effects on tumor cells of the activated mice lymphocyte.Results The proper gene of SEC_(2) was cloned and purified rSEC_(2) was obtained.The MTT results indicated that rSEC_(2) have strong ability to stimulate mice lymphocyte to proliferate with a dose-dependent manner.With the proliferation of mice splenic lymphocyte,rSEC_(2) has a strong lethal effect on tumor cells B16,K562 and K562-AD.Conclusion In this study,the gene of SEC_(2) was cloned and the rSEC_(2) protein was obtained,which had strong lethal effect on tumor cells B16,K562 and K562-AD.