Specific binding of erythropoietin to spleen cells infected with the anemia strain of Friend virus.
Specific binding of erythropoietin to spleen cells infected with the anemia strain of Friend virus.
复制标题
促红细胞生成素与感染弗兰德病毒贫血株的脾细胞特异性结合。
DOI：
10.1073/pnas.81.23.7574
复制
发表时间：
1984
影响因子：
11.1
通讯作者：
Goldwasser,E
中科院分区：
文献类型：
--
作者：
Krantz,SB;Goldwasser,E
已经制备了具有完全生物活性的氚化促红细胞生成素，并且通过用产生贫血的Friend病毒感染小鼠产生了对激素有反应的相对同质的富集祖细胞群体。这些细胞从感染小鼠的脾脏中获得，在促红细胞生成素的存在下发育成成熟的成红细胞和红细胞。我们测量了促红细胞生成素与这些靶细胞的结合; 62%的结合被过量的未标记促红细胞生成素抑制，但白蛋白、血清或各种生长因子和糖蛋白没有抑制作用。在37 ℃下2小时达到表观平衡，在10 ℃下3.5-4小时达到表观平衡。特异性结合的程度随细胞浓度线性增加。在10 ° C下的结合实验中，特异性结合的表观饱和发生在约等于8.7 nM处。Scatchard分析显示了一类单一的结合位点。解离常数为5.2 nM，平均每个细胞有660个结合位点。在0.06 nM时，大多数细胞在体外诱导终末分化，每个细胞平均仅结合8个促红细胞生成素分子。这些研究表明，促红细胞生成素附着于特异性结合位点，这些位点最有可能是受体，因为它们表现出高亲和力和特异性，并且该激素的生物学效应可以通过附着非常少量的促红细胞生成素分子来产生。
Tritiated erythropoietin with full biological activity has been prepared, and a relatively homogeneous population of enriched progenitor cells that respond to the hormone has been generated by infection of mice with the Friend virus that produces anemia. These cells, obtained from the spleens of infected mice, develop into mature erythroblasts and erythrocytes in the presence of erythropoietin. We have measured the binding of erythropoietin to these target cells; 62% of the binding was inhibited by excess unlabeled erythropoietin, but no inhibition occurred with albumin, serum, or a variety of growth factors and glycoproteins. Apparent equilibrium was reached by 2 hr at 37 degrees C and by 3.5-4 hr at 10 degrees C. The extent of specific binding increased linearly with cell concentration. In binding experiments at 10 degrees C, apparent saturation of specific binding occurred at approximately equal to 8.7 nM. Scatchard analysis showed a single class of binding sites. The dissociation constant is 5.2 nM with an average of 660 binding sites per cell. At 0.06 nM, where most of the cells are induced to terminally differentiate in vitro, an average of only 8 erythropoietin molecules bound per cell. These studies indicate that erythropoietin attaches to specific binding sites, which are most likely receptors since they manifest high affinity and specificity, and that the biologic effect of the hormone may be produced by attachment of a very small number of erythropoietin molecules.