Wide L, Bengtsson C
Department of Clinical Chemistry, University Hospital, Uppsala, Sweden.
Br J Haematol. 1990 Sep;76(1):121-7. doi: 10.1111/j.1365-2141.1990.tb07846.x.
The charge heterogeneity of human serum erythropoietin (S-Epo) was studied in 89 serum specimens from 78 subjects by zone electrophoresis in 0.17% agarose suspension at pH 8.6. The electrophoretic elution profiles of S-Epo were determined with a radioimmunoassay for Epo. The number of Epo peaks indicated that at least 20-30 different forms of Epo were present in a single serum specimen. The median charge of Epo, estimated as its median electrophoretic mobility, was determined for each serum specimen. This median charge was measured in 10 healthy adults, 46 patients with anaemia, six patients with secondary polycythaemia, one patient with polycythaemia vera treated by phlebotomy, and six healthy newborn infants (cord sera). Forty-four of the patients with anaemia had a median charge of S-Epo within the reference range for healthy adults, while all the patients with polycythaemia and the newborn infants had less negatively charged forms of S-Epo. In nine patients in whom the S-Epo level had a circadian rhythm, the forms of S-Epo in the evening were less negative than those in the morning. The median charge of recombinant preparations was much less negative than that of S-Epo in healthy individuals, while that of the 2nd International Reference Preparation was more negative than in any of the 78 subjects analysed. A significant change to less negatively charged S-Epo forms was observed 24 h after a subcutaneous injection of recombinant Epo in one patient, who before the injection had a normal median charge and concentration of S-Epo. In conclusion, Epo exhibits a considerable charge heterogeneity in individual serum specimens, the forms of S-Epo in the morning may differ from those in the evening, those in adults differ from those in newborn infants, and those in patients with anaemia differ from those in polycythaemia. The results also suggest that the methods used in this study may be useful for detecting the presence of injected recombinant Epo in the blood in persons with a normal endogenous Epo production.
采用pH 8.6的0.17%琼脂糖悬浮液区带电泳法，对78名受试者的89份血清标本中的人血清促红细胞生成素（S-Epo）电荷异质性进行了研究。用促红细胞生成素放射免疫分析法测定S-Epo的电泳洗脱图谱。促红细胞生成素峰的数量表明，单个血清标本中至少存在20 - 30种不同形式的促红细胞生成素。针对每个血清标本，测定以促红细胞生成素中位电泳迁移率估算的促红细胞生成素中位电荷。对10名健康成年人、46名贫血患者、6名继发性红细胞增多症患者、1名接受放血治疗的真性红细胞增多症患者以及6名健康新生儿（脐血血清）测量了该中位电荷。44名贫血患者的S-Epo中位电荷在健康成年人的参考范围内，而所有红细胞增多症患者和新生儿的S-Epo带负电形式较少。在9名S-Epo水平具有昼夜节律的患者中，晚上的S-Epo形式比早上的带负电程度更低。重组制剂的中位电荷比健康个体的S-Epo带负电程度低得多，而第二国际参考制剂的中位电荷比所分析的78名受试者中的任何一人都更带负电。在一名皮下注射重组促红细胞生成素24小时后的患者中观察到，其S-Epo形式明显转变为带负电程度更低的形式，该患者注射前S-Epo的中位电荷和浓度正常。总之，促红细胞生成素在个体血清标本中表现出相当大的电荷异质性，早上的S-Epo形式可能与晚上不同，成年人的与新生儿的不同，贫血患者的与红细胞增多症患者的不同。结果还表明，本研究中使用的方法可能有助于检测内源性促红细胞生成素产生正常的人群血液中注射的重组促红细胞生成素的存在。
