Rosias P P, Robroeks C M, Kester A, den Hartog G J, Wodzig W K, Rijkers G T, Zimmermann L J, van Schayck C P, Jöbsis Q, Dompeling E
Dept of Paediatric Pulmonology, Caphri Research Institute, University Hospital Maastricht, PO Box 5800, 6202 AZ Maastricht, The Netherlands.
Eur Respir J. 2008 May;31(5):934-42. doi: 10.1183/09031936.00073207. Epub 2008 Jan 9.
Optimal collection and analysis of exhaled breath condensate (EBC) are prerequisites for standardisation and reproducibility of assessments. The present study aimed to assess reproducibility of EBC volume, hydrogen peroxide (H(2)O(2)), 8-isoprostane and cytokine measurements using different condensers, including a newly developed glass condenser. At four points in time, 30 healthy subjects performed sequential EBC collections randomly using the following four condensers: glass, silicone, EcoScreen (Erich Jaeger GmbH, Hoechberg, Germany) and an optimised glass condenser. In small EBC samples, H(2)O(2) was measured by spectrophotometer, 8-isoprostane by enzyme immunoassay, and cytokines by multiplexed xMAP technology (Luminex Corporation, Austin, TX, USA). The optimised glass condenser yielded significantly more EBC volume (median 2,025 microL, interquartile range 1,600-2,525). The reproducibility of EBC volume, yielded by the new glass condenser, was comparable with EcoScreen (19-20 coefficients of variation (CV)%), but was significantly better compared with silicone and glass (29-37 CV%). The new condenser was associated with significantly more detections of H(2)O(2), 8-isoprostane, interleukin-2, -4, -5 and -13, and tumour necrosis factor-alpha. Isoprostane concentrations were significantly higher using the new condenser, whereas H(2)O(2) and cytokine concentrations were not. Reproducibility of biomarkers was equally variable for all condenser types. In conclusion, significantly more exhaled breath condensate volume and biomarker detections were found using the optimised glass condenser, including higher 8-isoprostane levels. However, biomarker reproducibility in exhaled breath condensate in healthy adults was not influenced by the type of condenser.
呼出气体冷凝液（EBC）的最佳采集与分析是评估标准化和可重复性的前提条件。本研究旨在评估使用不同冷凝器（包括新开发的玻璃冷凝器）对EBC体积、过氧化氢（H₂O₂）、8-异前列腺素和细胞因子测量的可重复性。在四个时间点，30名健康受试者使用以下四种冷凝器随机进行连续的EBC采集：玻璃冷凝器、硅胶冷凝器、EcoScreen（德国赫希贝格的Erich Jaeger GmbH公司）和优化后的玻璃冷凝器。在小体积EBC样本中，通过分光光度计测量H₂O₂，通过酶免疫测定法测量8-异前列腺素，通过多重xMAP技术（美国德克萨斯州奥斯汀的Luminex公司）测量细胞因子。优化后的玻璃冷凝器产生的EBC体积显著更多（中位数为2025微升，四分位间距为1600 - 2525）。新玻璃冷凝器产生的EBC体积的可重复性与EcoScreen相当（变异系数（CV）为19 - 20%），但与硅胶和玻璃冷凝器相比显著更好（CV为29 - 37%）。新冷凝器检测到的H₂O₂、8-异前列腺素、白细胞介素-2、-4、-5和-13以及肿瘤坏死因子-α显著更多。使用新冷凝器时异前列腺素浓度显著更高，而H₂O₂和细胞因子浓度则不然。所有冷凝器类型的生物标志物可重复性变化程度相同。总之，使用优化后的玻璃冷凝器发现呼出气体冷凝液体积和生物标志物检测显著更多，包括更高的8-异前列腺素水平。然而，健康成年人呼出气体冷凝液中生物标志物的可重复性不受冷凝器类型的影响。
