INTERLEUKIN-8 RECEPTOR OF HUMAN NEUTROPHILS

白介素8(IL-8)是一种约8 kDa的细胞因子多肽。 IL-8在中性粒细胞迁移和定位中起关键作用 (PMN)从外周血到炎症部位。这个 白介素8受体是一种由大约359个蛋白质组成的多肽。 氨基酸。受体被模拟为视紫红质样的七个螺旋 跨膜多肽与G蛋白信号通路相连。这个 这个项目的目的是确定受体的哪些区域是 与IL-8配体结合的关键。 我们已经建立了利用125I放射性标记的IL-8和 整个外周人类中性粒细胞。这个测试显示饱和的 受体在约1 nM的IL-8处与之竞争性结合 被过度寒冷的IL-8(300 NM)抑制。结合研究表明 中性粒细胞表面高、低亲和力IL-8受体的表达 浮出水面。 我们已经合成了对应于N-端和三个 受体分子的胞外环路。我们将利用上述优势 测定和这些多肽来确定IL-8受体的这些区域 它们在结合配体方面是至关重要的。 关键词：中性粒细胞免疫学；白介素8；受体结合

Interleukin-8 (IL-8) is a cytokine polypeptide of approximately 8 kDa. IL-8 plays a key role in the migration and localization of neutrophils (PMN) from the peripheral blood to sites of inflammation. The interleukin-8 receptor is a polypeptide made up of approximately 359 amino acids. The receptor is modeled as a rhodopsin-like seven helix membrane-spanning peptide linked to G protein signaling pathways. The aim of this project is to determine the regions of the receptor that are key in binding the IL-8 ligand. We have established a binding assay utilizing 125I radiolabeled IL-8 and whole peripheral human neutrophils. This assay exhibits saturation of the receptor at approximately 1 nM IL-8 and binding is competitively inhibited by excess cold IL-8 (300 nM). Binding studies indicate the presence of both high and low affinity IL-8 receptors on the PMN surface. We have synthesized peptides corresponding to the N-terminal and three extracellular loops of the receptor molecule. We will utilize the above assay and these peptides to determine those regions of the IL-8 receptor that are critical in binding ligand. Key words: Neutrophils-Immunology; Interleukin-8; Receptor Binding