title: High-level expression and one-step purification of a soluble recombinant human interleukin-37b in Escherichia coli.
abstract: Interleukin (IL)-37 is a novel member of the IL-1 cytokine family. However, as a result of lacking efficient method to generate relatively large quantity of IL-37, little is known of its functions in man. In the present study, the recombinant human IL-37b containing a C-hexahistidine tag was expressed in Escherichia coli (E. coli). The expression level of IL-37b in E. coli was very high after induction with IPTG. Furthermore, IL-37b protein was largely found in the soluble fraction. The expressed protein was readily purified by one-step immobilized metal-ion affinity chromatography using Ni(2+)-nitrilotriacetic acid agarose. The purified IL-37b appeared as a single band on SDS-PAGE and the purity was more than 97%. The yield was 90mg IL-37b from 1l of bacterial culture. Western blotting and N-terminal sequencing confirmed the identity of the purified protein. The purified IL-37b inhibited significantly the release of tumor necrosis factor-α and IL-1β in lipopolysaccharide-activated THP-1 cells. Thus, this method provides an efficient way to obtain an active IL-37 with high yield and high purity.
authors.affiliation: Department of Immunology, Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University School of Medicine, Ningbo 315211, China.
authors.forename: Jiajie
authors.initials: J
authors.lastname: Gu
authors.affiliation: Department of Immunology, Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University School of Medicine, Ningbo 315211, China.
authors.forename: Xueming
authors.initials: X
authors.lastname: Gao
authors.affiliation: Department of Immunology, Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University School of Medicine, Ningbo 315211, China.
authors.forename: Xiuhe
authors.initials: X
authors.lastname: Pan
authors.affiliation: Department of Immunology, Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University School of Medicine, Ningbo 315211, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Peng
authors.affiliation: Department of Histology and Embryology, Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University School of Medicine, Ningbo 315211, China. Electronic address: yanli319@yahoo.com.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Immunology, Zhejiang Provincial Key Laboratory of Pathophysiology, Ningbo University School of Medicine, Ningbo 315211, China. Electronic address: limingcai@nbu.edu.cn.
authors.forename: Mingcai
authors.initials: M
authors.lastname: Li
mesh_terms: D045744:Cell Line, Tumor / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology; D053583:Interleukin-1beta / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000494:pharmacology; D012995:Solubility; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: C508585:IL1B protein, human; C508587:IL37 protein, human; D007375:Interleukin-1; D053583:Interleukin-1beta; D008070:Lipopolysaccharides; D011993:Recombinant Fusion Proteins; D014409:Tumor Necrosis Factor-alpha
keywords: His-tag fusion protein; Interleukin-37; Recombinant; Soluble expression