Recombinant expression of human IL-17F fusion protein in E.coli and the study on its biological activity in vitro / 中国免疫学杂志

ABSTRACT

Objective:To construct a recombinant prokaryotic expression vector pGEX-5X-3/hIL-17F and express it in E.coli and to explore the biological activities of human IL-17F fusion protein.Methods:The coding sequence of the mature human IL-17F(minus the signal peptide) was amplified from pUCm-T/hIL-17F by PCR and subcloned into the prokaryotic expression vector pGEX-5X-3 to express glutathione S-transferase(GST) fusion protein. The fusion protein was induced in E.coli BL21 by IPTG and purified by standard methods reported in prokaryotic system. The purified GST-hIL-17F fusion protein was identified by Western blot. The proliferation of ECV304 cells was observed by incubating them with soluble GST-hIL-17F fusion protein by MTT assay. The concentrations of IL-6, IFN-? and TNF-? in the supernatants of ECV304 cells were determined by ELISA. The effect of GST-hIL-17F on the angiogenesis of the chick chorioallantoic membrane was assessed by CAM assay.Results:A 41 kD fusion protein was effciently induced in E.coli BL21 by IPTG, accounting for about 55% of the total bacterial protein. The purified GST-hIL-17F fusion protein was identified by Western blot. GST-hIL-17F fusion protein had obvious biological activity to inhibit the proliferation of ECV304 cells and enhance IL-6 secretion. GST-hIL-17F had a marked antiangiogenic activity.Conclusion:The preliminary study of hIL-17F recombinant prokaryotic expression and its antiangiogenic effect has been successful, which lays a foundation for future research on the mechanism of antiangiogenesis and clinical application of recombinant hIL-17F protein.