Rapid Production of Human KIR2DL4 Extracellular Domain and Verification of Its Interaction with HLA-G

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Yan-Rong Yu, Xing-Hui Tian, Yun Wang, and Mei-Fu Feng^*

State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, No. 25, BeiSiHuanXi Road, Beijing, 100080, P. R. China; fax: +86-10-62571017; E-mail: fengmf@ioz.ac.cn; yuyr@ioz.ac.cn

^* To whom correspondence should be addressed.

Received December 22, 2004; Revision received March 29, 2005

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Killer cell immunoglobulin-like receptor (KIR) 2DL4 is the only KIR member reported to be expressed by all human natural killer (NK) cells. It differs from other KIR members in both structure and function. Its specific interaction with HLA-G, a non-classical MHC class I molecule, has been suggested to play an important role in regulating NK cell-mediated cytotoxicity. However, this interaction is still in doubt. In addition, the soluble KIR2DL4 extracellular domain used in many studies was produced by eukaryotic expression, which is less efficient than prokaryotic expression. In this study, we describe a method of rapid production a large amount of soluble KIR2DL4 extracellular domain based on a prokaryotic expression system. With this soluble KIR2DL4, we verified the interaction between KIR2DL4 and HLA-G1.

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KEY WORDS: KIR2DL4, HLA-G1, natural killer cell, protein expression

DOI: 10.1134/S0006297906130104

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