一种用于血清和干血斑甲状腺球蛋白的新型低成本酶联免疫分析方法的开发与验证

Development and Validation of a New Low-Cost Enzyme-Linked Immunoassay for Serum and Dried Blood Spot Thyroglobulin.

作者信息

Stinca Sara, Andersson Maria, Erhardt Jürgen, Zimmermann Michael B

机构信息

Human Nutrition Laboratory, Institute of Food Nutrition and Health, Swiss Federal Institute of Technology (ETH) , Zurich, Switzerland .

出版信息

Thyroid. 2015 Dec;25(12):1297-305. doi: 10.1089/thy.2015.0428. Epub 2015 Dec 1.

DOI:10.1089/thy.2015.0428

PMID:26528830

Abstract

BACKGROUND

Thyroglobulin (Tg), a biomarker of iodine nutrition, can be measured on dried blood spots (DBS), which simplifies collection and transport in surveys. The World Health Organization recommends DBS-Tg for monitoring iodine status in children. It could also be a useful iodine biomarker during pregnancy. However, the Tg antibody (Ab) used in earlier DBS-Tg assays is no longer commercially available. The aims of the present study were: (i) to develop a new low-cost serum and DBS-Tg sandwich enzyme-linked immunosorbent assay for assessment of Tg in population studies; (ii) to check the stability of DBS-Tg during long-term storage; and (iii) to assess within-subject variability in DBS-Tg.

METHODS

Serum and DBS samples were measured from healthy pregnant women (n = 424) with the new assays, as well as the Immulite 2000 (Siemens), including TgAb positive (n = 150) and TgAb negative (n = 274) women. DBS-Tg stability was tested over 15 weeks of storage at -20 °C. Within-subject variability was evaluated over four weeks in four healthy adults.

RESULTS

Intra-assay and interassay variability was 4.4-7.3% and 10.1-12.9% for the new serum Tg assay, and 7.6-12.3% and 7.6-16.5% for the DBS-Tg assay. Correlation between the two serum methods was high (r = 0.68, p < 0.01). Assay performance in all women and those TgAb negative was comparable. Correlation between the new serum Tg assay and the DBS-Tg assay was high (r = 0.78, p < 0.01), and agreement expressed as a function of the average Tg concentration for the two methods (X) was 0.59X -4.59 μg/L. DBS-Tg was stable for 15 weeks stored at -20 °C. Within-subject variability in DBS-Tg was 21.1%. Reagents and antibodies costs for the new serum and DBS assays are ∼ US$1.

CONCLUSIONS

These new low-cost serum and DBS-Tg assays perform well over a wide range of Tg concentrations, and the field-friendly DBS assay may be particularly useful in population studies of iodine nutrition.

摘要

背景

甲状腺球蛋白（Tg）作为碘营养的生物标志物，可在干血斑（DBS）上进行检测，这简化了调查中的样本采集和运输过程。世界卫生组织推荐使用干血斑Tg检测来监测儿童的碘营养状况。它在孕期也可能是一种有用的碘生物标志物。然而，早期干血斑Tg检测中使用的Tg抗体已不再商业化供应。本研究的目的是：（i）开发一种新的低成本血清和干血斑Tg夹心酶联免疫吸附测定法，用于人群研究中Tg的评估；（ii）检查干血斑Tg在长期储存期间的稳定性；（iii）评估干血斑Tg的个体内变异性。

方法

使用新检测方法以及西门子Immulite 2000对424名健康孕妇的血清和干血斑样本进行检测，其中包括Tg抗体（TgAb）阳性（n = 150）和TgAb阴性（n = 274）的女性。在-20°C下储存15周，测试干血斑Tg的稳定性。在四名健康成年人中评估四周内的个体内变异性。

结果

新血清Tg检测的批内变异和批间变异分别为4.4 - 7.3%和10.1 - 12.9%，干血斑Tg检测的批内变异和批间变异分别为7.6 - 12.3%和7.6 - 16.5%。两种血清检测方法之间的相关性很高（r = 0.68，p < 0.01）。所有女性以及TgAb阴性女性的检测性能相当。新血清Tg检测与干血斑Tg检测之间的相关性很高（r = 0.78，p < 0.01），两种方法的Tg平均浓度（X）的一致性函数为0.59X - 4.59 μg/L。干血斑Tg在-20°C下储存15周稳定。干血斑Tg的个体内变异性为21.1%。新血清和干血斑检测的试剂和抗体成本约为1美元。