School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom.
PLoS One. 2013 Aug 1;8(8):e71315. doi: 10.1371/journal.pone.0071315. Print 2013.
Adiponectin is an adipocyte-derived hormone that acts as a marker of insulin sensitivity. Bloodspot sampling by fingerstick onto filter paper may increase the feasibility of large-scale studies of the determinants of insulin sensitivity. We first describe the validation of an enzyme-linked immunoassay (ELISA) for quantifying adiponectin from dried blood spots and then demonstrate its application in a large trial (PROBIT).
We quantified adiponectin from 3-mm diameter discs (≈3 µL of blood) punched from dried blood spots obtained from: i) whole blood standards (validation); and ii) PROBIT trial samples (application) in which paediatricians collected blood spots from 13,879 children aged 11.5 years from 31 sites across Belarus. We examined the distribution of bloodspot adiponectin by demographic and anthropometric factors, fasting insulin and glucose.
In the validation study, mean intra-assay coefficients of variation (n=162) were 15%, 13% and 10% for 'low' (6.78 µg/ml), 'medium' (18.18 µg/ml) and 'high' (33.13 µg/ml) internal quality control (IQC) samples, respectively; the respective inter-assay values (n=40) were 23%, 21% and 14%. The correlation coefficient between 50 paired whole bloodspot versus plasma samples, collected simultaneously, was 0.87 (95% CI: 0.78 to 0.93). Recovery of known quantities of adiponectin (between 4.5 to 36 µg/ml) was 100.3-133%. Bloodspot adiponectin was stable for at least 30 months at -80°C. In PROBIT, we successfully quantified fasting adiponectin from dried blood spots in 13,329 of 13,879 (96%) children. Mean adiponectin (standard deviation) concentrations were 17.34 µg/ml (7.54) in boys and 18.41 µg/ml (7.92) in girls and were inversely associated with body mass index, fat mass, triceps and subscapular skin-fold thickness, waist circumference, height and fasting glucose.
Bloodspot ELISA is suitable for measuring adiponectin in very small volumes of blood collected on filter paper and can be applied to large-scale studies.
脂联素是一种脂肪细胞衍生的激素，可作为胰岛素敏感性的标志物。通过手指穿刺在滤纸上采集血斑可能会增加对胰岛素敏感性决定因素进行大规模研究的可行性。我们首先描述了一种用于定量分析干血斑中脂联素的酶联免疫吸附测定法（ELISA）的验证，然后展示了其在大型试验（PROBIT）中的应用。
我们从以下两个方面定量分析了 3 毫米直径（约 3 μL 血液）的干血斑中的脂联素：i）全血标准品（验证）；ii）PROBIT 试验样本（应用），儿科学家从白俄罗斯 31 个地点采集了 13879 名 11.5 岁儿童的血斑。我们研究了血斑脂联素在人口统计学和人体测量学因素、空腹胰岛素和血糖方面的分布情况。
在验证研究中，对 162 份“低值”（6.78μg/ml）、“中值”（18.18μg/ml）和“高值”（33.13μg/ml）内部质量控制（IQC）样本的同批内变异系数分别为 15%、13%和 10%；对 40 份批间样本的相应值分别为 23%、21%和 14%。同时采集的 50 对全血斑与血浆样本之间的相关系数为 0.87（95%置信区间：0.78 至 0.93）。已知脂联素量（4.5 至 36μg/ml）的回收率为 100.3-133%。血斑脂联素在-80°C 下至少稳定 30 个月。在 PROBIT 中，我们成功地从 13879 名儿童中的 13329 名儿童的干血斑中定量分析了空腹脂联素。男孩的平均脂联素（标准差）浓度为 17.34μg/ml（7.54），女孩为 18.41μg/ml（7.92），与体重指数、脂肪量、肱三头肌和肩胛下皮褶厚度、腰围、身高和空腹血糖呈负相关。
血斑 ELISA 适用于测量滤纸采集的小体积血液中的脂联素，可应用于大规模研究。
