RESUMO
Objective To construct baculovirus expression system for the human plasminogen kringle 5(hK5) gene,and detect its expression in Spodoptera frugiperda 21(sf21). Methods Baculovirus Bacmid-rhK5 was prepared with bac-to-bac baculovirus expression system,and sf21 cells were infected.The expression of rhK5 in sf21 cells was determined by Western blot.The activity of purified protein was detected by vascular endothelial cell inhibition test. Results The pFastBac HTB-rhK5 was successfully constructed,and sf21 cells were transfected with the constructed vector.The output of rhK5 obtained was 90 ug/L,and the protein possessed the inhibitory activity of endothelial cell proliferation.The median effective dose(ED50) was 4 ug/mL. Conclusion The rhK5 baculovirus expression vector is highly expressed in sf21 cells,which lays a foundation for the the expression of rhK5 protein with biologic activities.