Shiina H, Ishibe T, Usui T
Department of Urology, Shimane Medical University, Izumo-shi, Japan.
Biochem Biophys Res Commun. 1989 Dec 29;165(3):947-55. doi: 10.1016/0006-291x(89)92695-8.
Estramustine binding protein (EMBP) was purified from the ventral prostate of the rat using DEAE-cellulose chromatography, concanavalin-A affinity chromatography and DEAE-sepharose chromatography. At the final step of the purification, two different peaks (Peaks A and B) of A280 nm were obtained. Peak A had a high binding activity to [3H] estramustine. On the other hand, Peak B had a low binding activity. On the analysis of polyacrylamide gel electrophoresis, Peak A gave two protein bands, whereas Peak B gave a single band. The molecular weight of the markedly stained band of Peak A was approximately 27,000, whereas that of Peak B was 18,000, as estimated by analysis of Fargusson's plot. The antibody against Peak B was used for establishing a radioimmunoassay (RIA) of EMBP. The sensitivity of this assay system was sufficient to measure of 1 ng of EMBP. The dilution curve of rat prostatic cytosol was paralleled with the standard curve. As a result obtained from this RIA, the mean concentration of immunoreactive EMBP was 8.01 ng/mg cytosol protein in human benign hyperplastic prostate (BPH) and 4.28 ng/mg protein in human prostatic carcinoma (PC), respectively. These results here obtained indicate that human prostate has an immunoreactive protein to the purified EMBP obtained from the ventral lobe of rat prostate.
雌莫司汀结合蛋白（EMBP）通过二乙氨基乙基纤维素色谱法、伴刀豆球蛋白A亲和色谱法和二乙氨基乙基琼脂糖色谱法从大鼠腹侧前列腺中纯化得到。在纯化的最后一步，获得了280nm处的两个不同峰（峰A和峰B）。峰A对[3H]雌莫司汀具有高结合活性。另一方面，峰B的结合活性较低。聚丙烯酰胺凝胶电泳分析显示，峰A出现两条蛋白带，而峰B出现一条蛋白带。根据法格森图分析估计，峰A明显染色带的分子量约为27,000，而峰B的分子量为18,000。针对峰B的抗体用于建立EMBP的放射免疫分析（RIA）。该分析系统的灵敏度足以检测1ng的EMBP。大鼠前列腺细胞溶质的稀释曲线与标准曲线平行。通过该RIA获得的结果显示，在人良性前列腺增生（BPH）中，免疫反应性EMBP的平均浓度为8.01ng/mg细胞溶质蛋白，在人前列腺癌（PC）中为4.28ng/mg蛋白。此处获得的这些结果表明，人前列腺对从大鼠前列腺腹叶纯化得到的EMBP具有免疫反应性蛋白。
