Regulatory Role of Interleukin 5 and Its Receptor in the Bcell Growth and Differentiation

白细胞介素5及其受体对B细胞生长和分化的调节作用

基本信息

批准号：
01044115
负责人：
TAKATSU Kiyoshi
金额：
$ 5.57万
依托单位：
Kumamoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for international Scientific Research
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1991
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01044115/
关键词：
Interleukin-5 (IL-5)IL-3 GM-CSF Cytokine IL-5 receptor Cytokine receptor family cDNA cloning B cell growth and differentiation Eosinophil growth and differentiation クロスハイブリダイゼ-ション TFー1 ILーS受容体 ILーS受容体cDNA サイトカインレセプタ-B前駆細胞株

项目摘要

We have characterized human IL-5 receptor (hIL-5R) by cloning cDNA with cross-species hybridization using murine IL-5R alpha chain cDNA as a probe. One cDNA clone encodes a glycoprotein of 420 amino acids (Mr 47, 670) with an N-terminal hydrophobic region (20 amino acids), a glycosylated extracellular domain (324 amino acids), a transmembrane domain (21 amino acids) and a cytoplasmic domain (55 amino acids).COS7 cells transfected with the cDNA expressed a 6OkD protein and bound IL-5 with a single class of affinity (Kd : 250-590 pM). The Kd values were similar with that observed in normal human eosinophils. The hIL-5R alpha chain characterized in this paper is an essential molecule for signal transduction, because expression of this molecule in murine IL-3 dependent cell line FDC-P1 allow these cells to proliferate in response to IL-5.In contrast to murine 60 kD alpha chain that binds IL-5 with low affinity (Kd : -IO nM), human alpha chain can bind IL-5 With much higher affinity by itself. In murine system, coexpression of beta chain (AIC2B, IL-3R homologue) with alpha chain increased the affinity at least 100-fold to that of alpha chain alone. Although hIL-5R alpha chain probably makes heterodyne with human GM-CSF receptor beta chain shared with IL-3 receptor, the contribution of hIL-5R beta chain to the increase of the affinity of alpha chain seems to be marginal. This may provide us an easier way to regulate eosinophil growth in human by designing an antagonist to hIL-5R alpha chain.We have also characterized several other cDNA clones for hIL-5R alpha chain with diversified 3' end. One of which does not have the transmembrane and cytoplasmic domains and probably codes for a soluble form of IL-5R alpha chain. These diversified 3' end may be involved in the regulation of the growth and differentiation of human eosinophils.

我们使用鼠 IL-5R α 链 cDNA 作为探针，通过跨物种杂交克隆 cDNA，从而表征了人 IL-5 受体 (hIL-5R)。一个 cDNA 克隆编码 420 个氨基酸的糖蛋白（Mr 47, 670），具有 N 端疏水区（20 个氨基酸）、糖基化胞外结构域（324 个氨基酸）、跨膜结构域（21 个氨基酸）和胞质结构域。结构域（55 个氨基酸）。用 cDNA 转染的 COS7 细胞表达 60kD 蛋白并以单一亲和力结合 IL-5 （Kd：250-590 下午）。 Kd 值与正常人嗜酸性粒细胞中观察到的值相似。本文表征的 hIL-5R α 链是信号转导的重要分子，因为该分子在小鼠 IL-3 依赖性细胞系 FDC-P1 中的表达使这些细胞能够响应 IL-5 而增殖。 60 kD α链以低亲和力结合IL-5(Kd：-10 nM)，人α链本身可以以高得多的亲和力结合IL-5。在小鼠系统中，β链（AIC2B、IL-3R同源物）与α链的共表达使亲和力比单独的α链增加至少100倍。虽然hIL-5R α链可能与与IL-3受体共享的人GM-CSF受体β链产生外差，但hIL-5R β链对α链亲和力增加的贡献似乎是微乎其微的。这可能为我们提供一种通过设计hIL-5R α链拮抗剂来调节人嗜酸性粒细胞生长的更简单的方法。我们还鉴定了具有多样化3'末端的hIL-5R α链的其他几个cDNA克隆。其中之一不具有跨膜和细胞质结构域，可能编码可溶形式的 IL-5R α 链。这些多样化的3'端可能参与人类嗜酸性粒细胞生长和分化的调节。