Differential binding of human interleukin-1 (IL-1) receptor antagonist to natural and recombinant soluble and cellular IL-1 type I receptors.
Differential binding of human interleukin-1 (IL-1) receptor antagonist to natural and recombinant soluble and cellular IL-1 type I receptors.
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人白介素 1 (IL-1) 受体拮抗剂与天然和重组可溶性和细胞 IL-1 I 型受体的差异结合。
DOI：
10.1002/eji.1830251020
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Bendtzen,K
中科院分区：
文献类型：
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作者：
Svenson,M;Nedergaard,S;Heegaard,PM;Whisenand,TD;Arend,WP;Bendtzen,K
最近描述的一种因子，白细胞介素-1受体拮抗剂结合因子（IL-1BF），在正常个体的血清中与I型白细胞介素-1受体（IL-1 RI）免疫相关。它可能是一种可溶性受体，仅与白细胞介素-1受体拮抗剂（IL-1 ra）结合。在COS细胞中表达的重组可溶性人IL-1 RI（sIL-1 RI）由受体的胞外部分组成，并结合所有三种已知的IL-1种类，但优先结合IL-1 ra。我们通过十二烷基硫酸钠存在下的聚丙烯酰胺凝胶电泳、配体结合干扰分析、N-糖苷酶处理、伴刀豆球蛋白A亲和层析以及使用人重组IL-1 ra的单克隆抗体（mAb）进一步表征了IL-1 raBF和sIL-1 RI的大小及其与IL-1 ra的结合。我们还评估了MRC 5成纤维细胞上IL-1 ra与细胞IL-1 RI的结合以及可溶性受体提供的干扰。结果表明，IL-1 raBF和sIL-1 RI的蛋白质骨架大小相似（约35-40 kDa），并且两种分子的糖基化存在差异。这些碳水化合物对于两种分子与IL-1 ra的最佳结合是必需的。这两种因子都阻断了IL-1 ra与细胞IL-1 RI的结合，就像mAb与IL-1 ra的结合一样，但IL-1 ra上与mAb、IL-1 raBF和sIL-1 RI结合的位点不同。我们的结论是，天然和重组形式的可溶性IL-1 RI之间存在重要差异，IL-1 ra与这些分子和细胞IL-1 RI的结合方式不同。
A recently described factor, interleukin‐1 receptor antagonist binding factor (IL‐IraBF), in serum of normal individuals is immunologically related to the interleukin‐1 receptor type I (IL‐1RI). It is presumably a soluble form of the receptor that binds exclusively to interleukin‐1 receptor antagonist (IL‐1ra). Recombinant soluble human IL‐1RI expressed in COS cells (sIL‐1RI) consists of the extracellular part of the receptor and binds all three known IL‐1 species but preferentially to IL‐1ra. We further characterized the sizes and binding of IL‐1raBF and sIL‐1RI to IL‐1ra by polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate, ligand binding interference analyses, N‐glycosidase treatment, concanavalin A affinity chromatography, and with the use of monoclonal antibodies (mAb) to human recombinant IL‐1ra. We also evaluated the binding of IL‐1ra to cellular IL‐1RI on MRC5 fibroblasts and the interference afforded by the soluble receptors. The results show that the protein backbones of IL‐1raBF and sIL‐1RI are of similar size (≈ 35–40 kDa) and that there are differences in the glycosylation of the two molecules. These carbohydrates were necessary for optimal binding of both molecules to IL‐1ra. Both factors blocked binding of IL‐1ra to cellular IL‐1RI, as did mAb to IL‐1ra, but the sites on IL‐1ra which bound to the mAb, and to IL‐1raBF and sIL‐1RI, differed. We conclude that there are important differences between the natural and recombinant forms of soluble IL‐1RI and that IL‐1ra binds differently to these molecules and to cellular IL‐1RI.