Sawitzke A L, Griffin J, Odell W D
Department of Physiology, University of Utah School of Medicine, Salt Lake City 84132.
J Clin Endocrinol Metab. 1991 Apr;72(4):841-6. doi: 10.1210/jcem-72-4-841.
We have identified a CG-like protein contaminating a purified human LH preparation of immunochemical grade. This CG-like material is estimated to comprise 0.17%, by weight, of the LH and reacts in specific, sequential-type, two-monoclonal antibody, immunoradiometric assays for CG as well as in the carboxyl-tail CG RIA. The CG-like material is not separable from LH by size exclusion or ion exchange chromatography. The LH can be freed of this small contamination of CG-like material by immunopurification employing specific monoclonal antibodies. Sephadex G-100 chromatography shows this material to have a mol wt of 40.0K. Western blot analysis of the LH run under nonreducing conditions, using an anti-CG carboxyl-tail primary antibody, reveals two bands of this CG-like material, one at 60.8K and one at 50.7K. When electrophoresed under reducing conditions, the material reacts with the anti-CG carboxyl-tail antibody at several mol wt, ranging from 10.5-64K.
我们已鉴定出一种类似绒毛膜促性腺激素（CG）的蛋白质，它污染了免疫化学级别的纯化人促黄体生成素（LH）制剂。据估计，这种类似CG的物质占LH重量的0.17%，并且在针对CG的特异性、顺序型双单克隆抗体免疫放射分析以及羧基末端CG放射免疫分析中发生反应。通过尺寸排阻色谱法或离子交换色谱法无法将这种类似CG的物质与LH分离。采用特异性单克隆抗体进行免疫纯化可去除LH中这种少量的类似CG物质的污染。葡聚糖凝胶G - 100色谱分析表明该物质的分子量为40.0K。在非还原条件下对LH进行蛋白质印迹分析，使用抗CG羧基末端一抗，可显示出两条这种类似CG物质的条带，一条在60.8K，另一条在50.7K。在还原条件下进行电泳时，该物质在10.5 - 64K的几个分子量处与抗CG羧基末端抗体发生反应。
