A major binding protein for leukemia inhibitory factor in normal mouse serum: identification as a soluble form of the cellular receptor.
A major binding protein for leukemia inhibitory factor in normal mouse serum: identification as a soluble form of the cellular receptor.
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DOI：
10.1073/pnas.89.18.8616
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发表时间：
1992-09
影响因子：
11.1
通讯作者：
Meredith J. Layton;Bronwyn A. Cross;Donald Metcalf;Larry D. Ward;Richard J. Simpson;Nicos A. Nicola
中科院分区：
文献类型：
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作者：
Meredith J. Layton;Bronwyn A. Cross;Donald Metcalf;Larry D. Ward;Richard J. Simpson;Nicos A. Nicola
通过使用四个连续的分级步骤，从正常小鼠血清中分离出特异性结合白血病抑制因子 (LIF) 的蛋白质：LIF 亲和基质色谱、阴离子交换色谱、尺寸排阻色谱和制备型非变性凝胶电泳。纯化的 LIF 结合蛋白 (LBP) 是一种表观分子量为 90 kDa 的糖蛋白，可特异性结合 125I 标记的小鼠 LIF，其亲和力与低亲和力细胞 LIF 受体相当 (Kd = 600 pM)。 N 端测序已鉴定该蛋白是细胞 LIF 受体 α 链的可溶性截短形式。 LBP 在正常小鼠血清中的含量很高（1 微克/毫升），并且这些水平在怀孕小鼠中升高，在新生小鼠中降低。由于 LBP 的正常血清浓度可以阻断培养物中 LIF 的生物学作用，因此 LBP 可以作为局部产生的 LIF 的全身效应的抑制剂。
A protein that specifically binds leukemia inhibitory factor (LIF) has been isolated from normal mouse serum by using four successive fractionation steps: chromatography on a LIF affinity matrix, anion-exchange chromatography, size-exclusion chromatography, and preparative native gel electrophoresis. The purified LIF-binding protein (LBP) is a glycoprotein with an apparent molecular mass of 90 kDa that specifically binds 125I-labeled murine LIF with an affinity comparable to that of the low-affinity cellular LIF receptor (Kd = 600 pM). N-terminal sequencing has identified this protein as a soluble truncated form of the alpha chain of the cellular LIF receptor. LBP is present in normal mouse serum at high levels (1 microgram/ml) and these levels are elevated in pregnant mice and reduced in neonatal mice. Since normal serum concentrations of LBP can block the biological actions of LIF in culture, LBP may serve as an inhibitor of the systemic effects of locally produced LIF.