Soluble Expression and One-Step Purification of Recombinant Mouse Interferon-λ3 in Escherichia coli

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Y. Q. Wang^#, M. Zhou^#, L. M. Zeng, Q. Y. Gao, X. L. Yuan, Y. Li^*, and M. C. Li^*

Zhejiang Provincial Key Laboratory of Pathophysiology, Department of Immunology, Ningbo University School of Medicine, Ningbo 315211, China; fax: +86-574-87609893; E-mail: yanli319@yahoo.com; limingcai@nbu.edu.cn

^# These authors contributed equally to this work.

^* To whom correspondence should be addressed.

Received May 22, 2014; Revision received August 26, 2014

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Interferon (IFN)-λ3, a member of the type III IFN family, is a pleiotropic cytokine that exhibits potent antiproliferative, antiviral, and immunoregulatory activities. For further functional study of IFN-λ3, we developed an efficient procedure that includes cloning, expression, and purification to obtain relatively large quantity of mouse IFN-λ3 fusion protein. The mature IFN-λ3 protein-coding region was cloned into the prokaryotic expression vector pET-44. IFN-λ3 contains a hexahistidine tag at its C-terminus. We used Ni²⁺-nitrilotriacetic acid agarose-affinity chromatography to purify the expressed soluble protein. The purified IFN-λ3 inhibited significantly IL-13 production in stimulated RAW264.7 macrophages. Our findings show that the production of soluble IFN-λ3 proteins by the pET-44 vector in Escherichia coli is a good alternative for the production of native IFN-λ3 and could be useful for the production of other IFN proteins.

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KEY WORDS: interferon-λ3, recombinant protein, Escherichia coli, pET-44 vector

DOI: 10.1134/S0006297915020091

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