Gaines-Das R E, Bristow A F, Brettschneider H
WHO International Laboratory for Biological Standards National Institute for Biological Standards and Control Blanche Lane South Mimms, Hertfordshire Potters Bar EN6 3QG UK.
J Automat Chem. 1991;13(5):209-15. doi: 10.1155/S1463924691000354.
This report describes the results of a collaborative study organized by a joint working group of the IFCC and WHO and involving nine manufacturers of TSH immunometric assay kits. The study was designed to determine whether a calibrator with a common matrix gives better between-laboratory agreement for calibration of serum samples than the various kit calibrators, and to assess various materials for their suitability for use as common matrices. Kit calibrators, or calibrators consisting of the IRP for TSH made up in two common matrices: (a) serum from patients with untreated thyrotoxicosis or (b) serum taken from subjects treated with suppressive doses of triiodothyronine, gave similar results for the between-laboratory variation of estimates of TSH concentration for a range of serum samples. Dose-response curves for the two calibrators in 'common' matrices were similar to one another and to those for the kit calibrator. However, the occurrence of non-specific serum effects is shown by the comparison of results for these calibrators with results for calibrators made up in a third common matrix: serum treated with wheat germ lectin. Dose response curves for this calibrator were dissimilar to those for the other calibrators and between-laboratory variation for estimates in terms of this latter calibrator showed a substantial increase. Moreover, although the between-laboratory variances for estimates of the TSH concentration in terms of each of these calibrators (except those made up in serum treated with the wheat germ lectin) were similar for any one sample from five hyperthyroid patients, the variances were not consistent between samples, even for samples with similar mean TSH concentrations. These results suggest that a major factor in the between-laboratory variation, especially in the region near 'zero dose', is sample-related, and is caused by particular samples interacting differently with different assay systems.In general, it would appear that for the well-controlled 'ultrasensitive' TSH immunometric assay kits, included in this study, between-laboratory agreement of estimates of the TSH concentration in serum samples is not likely to be substantially improved by use of a common matrix for the standards.
本报告描述了由国际临床化学和检验医学联合会（IFCC）与世界卫生组织（WHO）联合工作组组织开展的一项合作研究的结果，该研究涉及9家促甲状腺激素免疫测定试剂盒制造商。该研究旨在确定具有通用基质的校准品用于血清样本校准是否比各种试剂盒校准品能产生更好的实验室间一致性，并评估各种材料作为通用基质的适用性。试剂盒校准品，或由促甲状腺激素国际参考品（IRP）制成的校准品，采用两种通用基质：（a）未经治疗的甲状腺毒症患者的血清，或（b）接受抑制剂量三碘甲状腺原氨酸治疗的受试者的血清，对于一系列血清样本促甲状腺激素浓度估计值的实验室间变异给出了相似结果。两种“通用”基质校准品的剂量反应曲线彼此相似，且与试剂盒校准品的剂量反应曲线相似。然而，通过将这些校准品的结果与由第三种通用基质制成的校准品（经麦胚凝集素处理的血清）的结果进行比较，显示出非特异性血清效应的存在。该校准品的剂量反应曲线与其他校准品不同，且基于该校准品估计值的实验室间变异显著增加。此外，尽管对于来自5名甲状腺功能亢进患者的任何一个样本，基于这些校准品（除了经麦胚凝集素处理的血清制成的校准品）中每一种校准品的促甲状腺激素浓度估计值的实验室间方差相似，但即使对于平均促甲状腺激素浓度相似的样本，样本之间的方差也不一致。这些结果表明，实验室间变异的一个主要因素，尤其是在“零剂量”附近区域，与样本相关，是由特定样本与不同检测系统的相互作用方式不同所致。总体而言，对于本研究中纳入的控制良好的“超灵敏”促甲状腺激素免疫测定试剂盒，使用通用基质作为标准品不太可能显著提高血清样本促甲状腺激素浓度估计值的实验室间一致性。
