Sander Ingrid, Lotz Anne, Zahradnik Eva, Raulf Monika
Department of Allergology, Center of Allergology/Immunology, Institute for Prevention and Occupational Medicine, German Social Accident Insurance, Ruhr University Bochum (IPA), Bürkle-de-la-Camp-Platz 1, D-44789 Bochum, Germany
Center of Epidemiology, Institute for Prevention and Occupational Medicine, German Social Accident Insurance, Ruhr University Bochum (IPA), Bürkle-de-la-Camp-Platz 1, D-44789 Bochum, Germany.
Ann Occup Hyg. 2016 Aug;60(7):845-59. doi: 10.1093/annhyg/mew027. Epub 2016 May 26.
Sampling of endotoxin, beta-glucan, or allergens on electrostatic dust collectors (EDCs) is a convenient method for exposure assessment. However, especially for allergens few experiments on validation of this method concerning deployment time or storage and extraction procedure have been performed. The aim of study was to optimize the EDC procedure for sampling of allergens in indoor environments. EDCs were placed in households or day-care centers and after extraction, allergens were quantified by six immunoassays detecting mite antigens (Domestic mites DM, Dermatophagoides pteronyssinus Dp, Tyrophagus putrescentiae Tp) or the main allergens from cat (Fel d 1), dog (Can f 1) and mouse (Mus m 1). For 20 EDC holders, deployment times of cloths were varied between 7 and 28 days, 36 EDCs were used to test reproducibility, and for 28 EDCs extraction buffers were varied (with or without 0.05% Tween 20, borate, or phosphate buffer). The influence of storage of cloths at room temperature (2-629 days) or extracts at -80°C (7-639 days), and variation of extract storage temperature (-20°C and -80°C) for long time storage (1.5 years) on the outcome of allergen quantification were tested for about 150 EDCs. The allergens on EDC cloths increased proportionally with deployment time, and allergen loads on parallel sampled tissues were significantly correlated (P < 0.0001, Pearson of log-transformed values 0.91-0.99). Extraction without Tween reduced all results (P < 0.0001, -51% DM, -85% Dp, -60% Tp, -99% Fel d 1, -86% Can f 1, -52% Mus m 1), and borate buffer resulted in lower yields of Mus m 1 (-53%), DP (-45%), and Tp (-27%) than phosphate buffer. Storage of cloths at room temperature significantly decreased Can f 1 levels (P < 0.0001, -4.8% loss for every 30 days), whereas storage of extracts at -80°C decreased DM results (P < 0.0001, -1.2% loss for every 30 days). Extracts stored at -20°C gave at mean 12% higher DM results compared to extracts stored at -80°C for 1.5 years. Several mammalian allergens and also DM antigens could be quantified reproducibly on EDCs from indoor environments. Allergen levels on EDC cloths increased proportionally with deployment time in a period of 4 weeks. Allergen yields are strongly influenced by the extraction procedure; the use of detergent Tween 20 and phosphate buffer is recommended.
在内置静电集尘器（EDC）上采集内毒素、β-葡聚糖或过敏原是一种便捷的暴露评估方法。然而，尤其是对于过敏原，针对该方法在部署时间、储存及提取程序方面的验证实验开展较少。本研究的目的是优化在室内环境中采集过敏原的EDC程序。将EDC放置于家庭或日托中心，提取后，通过六种免疫测定法对过敏原进行定量分析，这些方法可检测螨虫抗原（屋尘螨DM、粉尘螨Dp、腐食酪螨Tp）或来自猫（猫过敏原Fel d 1）、狗（犬过敏原Can f 1）和小鼠（小鼠过敏原Mus m 1）的主要过敏原。对于20个EDC支架，滤布的部署时间在7至28天之间变化，使用36个EDC测试重现性，并对28个EDC的提取缓冲液进行了变化（添加或不添加0.05%吐温20、硼酸盐或磷酸盐缓冲液）。测试了约150个EDC在室温下储存滤布（2 - 629天）或在 - 80°C下储存提取物（7 - 639天）以及长时间储存（1.5年）时提取物储存温度变化（ - 20°C和 - 80°C）对过敏原定量结果的影响。EDC滤布上的过敏原随部署时间成比例增加，平行采样组织上的过敏原负荷显著相关（P < 0.0001，对数转换值的Pearson相关性为0.91 - 0.99）。不使用吐温的提取方法降低了所有结果（P < 0.0001，DM降低51%，Dp降低85%，Tp降低60%，Fel d 1降低99%，Can f 1降低86%，Mus m 1降低52%），硼酸盐缓冲液导致Mus m 1（ - 53%）、Dp（ - 45%）和Tp（ - 27%）的产量低于磷酸盐缓冲液。室温下储存滤布显著降低了Can f 1水平（P < 0.0001，每30天损失4.8%），而在 - 80°C下储存提取物降低了DM结果（P < 0.0001，每30天损失1.2%）。与在 - 80°C下储存1.5年的提取物相比，在 - 20°C下储存的提取物平均DM结果高12%。在室内环境的EDC上可以对几种哺乳动物过敏原以及DM抗原进行可重复的定量分析。在4周的时间内，EDC滤布上的过敏原水平随部署时间成比例增加。过敏原产量受提取程序的强烈影响；建议使用去污剂吐温20和磷酸盐缓冲液。
