Schiettecatte J, De Schepper J, Velkeniers B, Smitz J, Van Steirteghem A
Laboratory of Radioimmunology, University Hospital, Brussels Free University (Dutch speaking), Belgium.
Clin Chem Lab Med. 2001 Dec;39(12):1244-8. doi: 10.1515/CCLM.2001.200.
Immunoprecipitation with anti-human immunoglobulin G-agarose was evaluated for the detection of prolactin-immunoglobulin G (PRL-IgG) complexes in macroprolactinemic samples from hyperprolactinemic patients (prolactin measured using the automated Elecsys PRL assay; Roche Diagnostics, Mannheim, Germany). Using the polyethylene glycol (PEG) precipitation test on serum samples with PRL above 1000 mIU/l, we detected macroprolactin in 38 out of 175 samples with a recovery below 50%. Gel filtration chromatography on a subset of hyperprolactinemic samples confirmed that macroprolactin was the predominant immunoreactive form of PRL in samples which showed a recovery < or = 50%. In 37 out of 38 samples containing macroprolactin, immunoprecipitation with anti-human IgG (anti-hIgG)-agarose revealed a higher PRL-binding (19.1-91.3%) than in the sera containing monomeric PRL (< 10%). In conclusion, we found that PEG precipitation detected macroprolactin in 21.7% of samples with elevated PRL levels as measured by the Elecsys PRL assay, and that in the vast majority of these samples the presence of PRL-IgG complexes could be demonstrated by immunoprecipitation with anti-hIgG-agarose. In view of the high prevalence of PRL-IgG complexes in hyperprolactinemic patients and the simplicity of the test, immunoprecipitation with anti-hIgG-agarose might play a role in the routine laboratory handling of hyperprolactinemic samples, especially with regards to PRL assays where PEG causes interference.
采用抗人免疫球蛋白G-琼脂糖免疫沉淀法，对高催乳素血症患者的巨催乳素血症样本中催乳素-免疫球蛋白G（PRL-IgG）复合物进行检测（催乳素采用罗氏诊断公司（德国曼海姆）的Elecsys PRL自动检测法测定）。对催乳素水平高于1000 mIU/l的血清样本进行聚乙二醇（PEG）沉淀试验，我们在175份样本中的38份中检测到巨催乳素，回收率低于50%。对一部分高催乳素血症样本进行凝胶过滤层析，证实巨催乳素是催乳素回收率≤50%的样本中主要的免疫反应形式。在38份含有巨催乳素的样本中，有37份样本采用抗人IgG（抗-hIgG）-琼脂糖免疫沉淀法显示出比含有单体PRL的血清更高的PRL结合率（19.1 - 91.3%）（< 10%）。总之，我们发现PEG沉淀法在采用Elecsys PRL检测法测定的催乳素水平升高的样本中，有21.7%检测到巨催乳素，并且在这些样本中的绝大多数中，通过抗-hIgG-琼脂糖免疫沉淀法可证实存在PRL-IgG复合物。鉴于高催乳素血症患者中PRL-IgG复合物的高发生率以及该检测方法的简便性，抗-hIgG-琼脂糖免疫沉淀法可能在高催乳素血症样本的常规实验室处理中发挥作用，特别是在PEG会造成干扰的PRL检测方面。
