Cloning of human interleukin-24 gene and its high efficiency expression in E. coli / 吉林大学学报(医学版)

ABSTRACT

Objective To construct a recombinant expression vector of human interleukin-24(hIL-24) gene and express it in E.coli M15,and to evaluate the bioactivity of IL-24 fusion protein.Methods The human IL-24 cDNA fragment was amplified from plasmid by polymerase chain reaction(PCR),and sequenced.PQE/hIL-24 was constructed by gene rearrangement,then it was transformed into E.coli M15.The expression of the target protein was induced with IPTG and purified by Ni2+-NTA agarose column.The expressed recombinant hIL-24(rhIL-24) was identified by SDS-PAGE and Western blotting.Normal peripheral blood mononuclear cells(PBMCs) were cultivated with the expression protein for 48 and 72 h,the levels of IL-6,IFN-? and TNF-? of PBMCs stimulated with rhIL-24 were detected by ELISA.Results The recombinant prokaryotic expression vector PQE/IL-24 was constructed successfully and expressed stably in E.coli M15.At about 18 400 of molecular weight,there was an induced protein band.The levels of IFN-?,IL-6 and TNF-? in the group of cultivated with the expression protein were obviously higher than those in the groups without the expresson protein(P