Kaji M, Ikari M, Hashiguchi S, Ito Y, Matsumoto R, Yoshimura T, Sugimura K
Department of Bioengineering, Faculty of Engineering, Kagoshima University, Korimoto, Kagoshima 890-0065, Japan.
J Biochem. 2001 Apr;129(4):577-83. doi: 10.1093/oxfordjournals.jbchem.a002893.
In this study, we attempted to analyze the peptide motifs recognized by 24822.111 and F9, monoclonal antibodies (mAbs) that inhibit the chemotactic activity of monocyte chemoattractant protein-1 (MCP-1), a member of the CC subfamily of chemokines. We isolated phage clones from a phage display library and identified six peptide motifs. One of these clones, C27, was strongly and specifically recognized by 24822.111 mAb, while another, G25, was similarly recognized by F9 mAb. Both the C27 motif and the G25 motif contain two cysteines in their sequences and have little homology to the primary amino acid sequence of MCP-1. These clones, however, bound to THP-1 cells, and the binding was competitively inhibited by MCP-1. The clones strongly inhibited the MCP-1-induced chemotaxis of human monocytes. The synthetic and intramolecularly disulfide-linked peptides of C27 and G25 (sC27 and sG25) also inhibited the chemotaxis induced by MCP-1, while their derivatives with serine in place of cysteine did not, suggesting the importance of the loop structure for the inhibition. These results suggest that sC27 and sG25 may mimic the MCP-1-binding domain to the MCP-1 receptor.
在本研究中，我们试图分析24822.111和F9这两种单克隆抗体（mAb）所识别的肽基序，这两种抗体可抑制趋化因子CC亚家族成员单核细胞趋化蛋白-1（MCP-1）的趋化活性。我们从噬菌体展示文库中分离出噬菌体克隆，并鉴定出六个肽基序。其中一个克隆C27被24822.111单克隆抗体强烈且特异性地识别，而另一个克隆G25被F9单克隆抗体类似地识别。C27基序和G25基序在其序列中均含有两个半胱氨酸，并且与MCP-1的一级氨基酸序列几乎没有同源性。然而，这些克隆与THP-1细胞结合，并且这种结合被MCP-1竞争性抑制。这些克隆强烈抑制MCP-1诱导的人单核细胞趋化。C27和G25的合成且分子内二硫键连接的肽（sC27和sG25）也抑制MCP-1诱导的趋化，而用丝氨酸取代半胱氨酸的衍生物则没有，这表明环结构对抑制作用很重要。这些结果表明，sC27和sG25可能模拟MCP-1与MCP-1受体的结合域。
