Hoermann R, Spoettl G, Grossmann M, Saller B, Mann K
Medizinische Klinik II, Klinikum Grosshadern, Ludwig-Maximilians-Universität München.
Clin Investig. 1993 Nov;71(11):953-60. doi: 10.1007/BF00185610.
Many studies on the structure and function of human chorionic gonadotropin (hCG) have relied on purified hCG preparations obtained from pregnancy urine. In the present studies, in order to demonstrate possible differences between the hCG species present in serum and those released into urine, we examined serum and urinary samples derived from patients with trophoblastic tumors and of pregnancy origin by sodium dodecyl sulfate electrophoresis, isoelectric focusing, and two-dimensional electrophoresis including immunostaining with a specific hCG antibody and densitometry of the protein bands. This type of analysis was presently feasible only in patients presenting with extremely high serum levels of hCG and was therefore limited to seven patients with testicular cancers, one woman with a hydatidiform mole, and one pregnancy sample. We found marked differences in the isoelectric focusing pattern between urinary and serum hCG samples, with the urinary hCG consisting of more alkaline pI variants than that present in the serum of the same patients. Tumor hCG differed from pregnancy hCG in that it contained more acidic variants, and this was true for urinary and serum-derived materials. In some tumor and pregnancy samples an hCG immunoreactive material of lower molecular weight than hCG itself was found. In conclusion, the present studies, extending previous findings on the microheterogeneity of hCG, indicate that serum and urinary-derived hCG may differ in the composition of the isoform spectrum, as does tumor and pregnancy hCG. Further, in some patients hCG immunoreactive molecules exist that differ markedly from hCG in size and charge. These observations suggest that, whenever possible, serum-derived hCG materials should be used to define the molecular structure of hCG and assess its biological activities.
许多关于人绒毛膜促性腺激素（hCG）结构与功能的研究都依赖于从妊娠尿液中获得的纯化hCG制剂。在本研究中，为了证明血清中存在的hCG种类与释放到尿液中的hCG种类之间可能存在的差异，我们通过十二烷基硫酸钠电泳、等电聚焦和二维电泳（包括用特异性hCG抗体进行免疫染色以及对蛋白条带进行光密度测定），对来自滋养层细胞瘤患者和妊娠来源的血清及尿液样本进行了检测。这种分析类型目前仅在hCG血清水平极高的患者中可行，因此仅限于7例睾丸癌患者、1例葡萄胎女性患者以及1份妊娠样本。我们发现尿液和血清hCG样本的等电聚焦模式存在显著差异，尿液hCG比同一患者血清中的hCG含有更多碱性pI变体。肿瘤hCG与妊娠hCG的不同之处在于它含有更多酸性变体，尿液和血清来源的物质均如此。在一些肿瘤和妊娠样本中，发现了一种分子量低于hCG本身的hCG免疫反应性物质。总之，本研究扩展了先前关于hCG微异质性的发现，表明血清和尿液来源的hCG在同工型谱组成上可能存在差异，肿瘤和妊娠hCG也是如此。此外，在一些患者中存在hCG免疫反应性分子，其大小和电荷与hCG明显不同。这些观察结果表明，只要有可能，应使用血清来源的hCG材料来确定hCG的分子结构并评估其生物学活性。
