Kardana A, Taylor M E, Rowan A J, Read D A, Bagshawe K D
Cancer Research Campaign Laboratories, Charing Cross Hospital, London, UK.
J Immunol Methods. 1989 Mar 10;118(1):53-8. doi: 10.1016/0022-1759(89)90052-5.
There is now general recognition that human chorionic gonadotropin (hCG), its beta subunit and its fragments are valuable diagnostic markers of trophoblastic and some non-trophoblastic malignancies. Urinary gonadotropin peptide (UGP) contains at least one epitope which cross-reacts with the beta-subunit of hCG. In order to assess the potential of UGP as a tumour marker in its own right, it was paramount that any measurements made could be regarded as specific for UGP and not cross-reactive with either hCG or human luteinising hormone (hLH). Four antibodies were tested, two polyclonal (AK12 and DR-Pool) and two monoclonal (2C2 and 6D3). Initial screening using radioiodinated (125I) UGP, hCG, hCG beta-subunit and hLH showed that the polyclonal antibodies bound to all four gonadotrophins, whilst the monoclonal antibodies bound only to the radioiodinated UGP. The antibodies were tested in both radioimmunoassay (RIA) and immunoradiometric assay (IRMA-sandwich assay) systems. The parameters measured were sensitivity and specificity for UGP. The polyclonal antibodies used in the RIA system produced a sensitive assay (0.2 ng/ml UGP) which was relatively specific; cross-reactions for the AK12 antibody (at 50% inhibition) were 5% for hCG, 11% for its beta-subunit, 0.4% for the alpha-subunit and 2.6% for hLH. The monoclonal antibodies performed optimally in the IRMA system. Immobilised 2C2 and radiolabelled (125I) AK12 produced a system that had a sensitivity of 0.4 ng/ml UGP and cross-reactivity (50% maximum binding) of 2% for the hCG beta-subunit and less than 1% for hCG, hLH and the hCG alpha-subunit.
目前人们普遍认识到，人绒毛膜促性腺激素（hCG）、其β亚基及其片段是滋养层细胞和一些非滋养层细胞恶性肿瘤的重要诊断标志物。尿促性腺激素肽（UGP）至少含有一个与hCG的β亚基发生交叉反应的表位。为了评估UGP自身作为肿瘤标志物的潜力，至关重要的是，所进行的任何测量都应被视为对UGP具有特异性，且不与hCG或人促黄体生成素（hLH）发生交叉反应。测试了四种抗体，两种多克隆抗体（AK12和DR-Pool）和两种单克隆抗体（2C2和6D3）。使用放射性碘化（125I）的UGP、hCG、hCGβ亚基和hLH进行的初步筛选表明，多克隆抗体与所有四种促性腺激素结合，而单克隆抗体仅与放射性碘化的UGP结合。在放射免疫分析（RIA）和免疫放射分析（IRMA-夹心分析）系统中对这些抗体进行了测试。所测量的参数是UGP的灵敏度和特异性。RIA系统中使用的多克隆抗体产生了一种灵敏的分析方法（UGP为0.2 ng/ml），且相对具有特异性；AK12抗体的交叉反应（50%抑制时），hCG为5%，其β亚基为11%，α亚基为0.4%，hLH为2.6%。单克隆抗体在IRMA系统中表现最佳。固定化的2C2和放射性标记（125I）的AK12产生了一个系统，其对UGP的灵敏度为0.4 ng/ml，对hCGβ亚基的交叉反应（最大结合的50%）为2%，对hCG、hLH和hCGα亚基的交叉反应小于1%。
