Center for Studies in Demography and Ecology, University of Washington, Seattle, Washington, United States of America.
PATH, Seattle, Washington, United States of America.
PLoS One. 2022 Nov 21;17(11):e0277835. doi: 10.1371/journal.pone.0277835. eCollection 2022.
Processing and storing blood samples for future analysis of biomarkers can be challenging in resource limited environments. The preparation of dried blood spots (DBS) from finger-stick collection of whole blood is a widely used and established method as DBS are biosafe, and allow simpler field processing, storage, and transport protocols than serum or plasma. Therefore, DBS are commonly used in population surveys to assess infectious disease and/or micronutrient status. Recently, we reported that DBS can be used with the Q-plex™ Human Micronutrient 7-plex Array (MN 7-plex), a multiplexed immunoassay. This tool can simultaneously quantify seven protein biomarkers related to micronutrient deficiencies (iodine, iron and vitamin A), inflammation, and malarial antigenemia using plasma or serum. Serum ferritin, an iron biomarker, cannot be measured from DBS due to red blood cell (RBC) ferritin content confounding the results. In this study, we assess a simple blood fractionation tool that passively separates plasma from other blood components via diffusion through a membrane into a plasma collection disc (PCD). We evaluated the concordance of MN 7-plex analyte concentrations from matched panels of eighty-eight samples of PCD, DBS, and wet plasma prepared from anticoagulated venous whole blood. The results showed good correlations of >0.93 between the eluates from PCD and DBS for each analyte except ferritin; while correlations seen for plasma/PCD were weaker. However, the recovery rate of the analytes from the PCD were better than those from DBS. The serum ferritin measures from the PCD were highly correlated to wet plasma samples (0.85). This suggests that surveillance for iron status in low resource settings can be improved over the current methods restricted to only measuring sTfR in DBS. When used in combination with the MN 7-plex, all seven biomarkers can be simultaneously measured using eluates from the PCDs.
在资源有限的环境中，处理和储存血液样本以供未来分析生物标志物可能具有挑战性。从手指穿刺采集的全血制备干血斑（DBS）是一种广泛使用且成熟的方法，因为 DBS 是生物安全的，并且与血清或血浆相比，允许更简单的现场处理、储存和运输方案。因此，DBS 常用于人群调查以评估传染病和/或微量营养素状况。最近，我们报告说，DBS 可与 Q-plex™ 人类微量营养素 7 合一心血管疾病标志物检测试剂盒（MN 7-plex）一起使用，这是一种多重免疫分析工具。该工具可以使用血浆或血清同时定量七种与微量营养素缺乏（碘、铁和维生素 A）、炎症和疟原抗原血症相关的蛋白质生物标志物。由于红细胞（RBC）铁蛋白含量会干扰结果，因此不能从 DBS 测量血清铁蛋白这一铁生物标志物。在这项研究中，我们评估了一种简单的血液分离工具，该工具通过扩散穿过膜进入血浆收集盘（PCD）将血浆与其他血液成分被动分离。我们评估了来自 88 个配对样本的 PCD、DBS 和抗凝静脉全血制备的湿血浆的 MN 7-plex 分析物浓度的一致性。结果表明，除铁蛋白外，PCD 和 DBS 的洗脱液中每个分析物的相关性均>0.93；而血浆/PCD 的相关性较弱。然而，PCD 中分析物的回收率优于 DBS。PCD 中测量的血清铁蛋白与湿血浆样本高度相关（0.85）。这表明，在当前仅限制在 DBS 中测量 sTfR 的方法的基础上，在资源匮乏的环境中可以改善铁状态的监测。当与 MN 7-plex 结合使用时，所有七种生物标志物都可以使用 PCD 的洗脱液同时测量。
