Sandström T, Ledin M C, Thomasson L, Helleday R, Stjernberg N
National Institute of Occupational Health, Medical Division, Umeå, Sweden.
Br J Ind Med. 1992 Dec;49(12):850-4. doi: 10.1136/oem.49.12.850.
In this investigation the effects of repeated exposure to 1.5 ppm NO2 on immune competent cells in bronchoalveolar lavage (BAL) fluid was studied. Special attention was focused on effects on lymphocyte subpopulations. Eight healthy subjects were exposed to 1.5 ppm NO2 every second day on six occasions. Bronchoalveolar lavage fluid was collected at least three weeks before the exposure series as reference and 24 hours after the last exposure. The results obtained were analysed using a non-parametric test for paired observations, with each subject as his own control. Significant reductions were found in the total number and percentage of T cytotoxic-suppressor cells in BAL fluid; this caused an increase in the ratio of T helper-inducer: cytotoxic-suppressor cells. The total number of natural killer cells in the BAL fluid was also reduced. The numbers of all other cell types were unchanged after exposure. No reduction of phagocytosis of opsonised yeast particles by alveolar macrophages in vitro was detected. It is concluded that repeated short term exposures to 1.5 ppm NO2, a moderate occupational concentration, induces significant effects on immune competent bronchoalveolar lymphocytes. This indicates that previous findings of changes in the lymphoid immune system induced by NO2 in animals may well be applicable to humans.
在本研究中，研究了反复暴露于1.5 ppm二氧化氮对支气管肺泡灌洗（BAL）液中免疫活性细胞的影响。特别关注对淋巴细胞亚群的影响。八名健康受试者每隔一天暴露于1.5 ppm二氧化氮，共六次。在暴露系列之前至少三周收集支气管肺泡灌洗液作为对照，并在最后一次暴露后24小时收集。使用非参数配对观察检验分析所得结果，每个受试者作为自身对照。发现BAL液中T细胞毒性抑制细胞的总数和百分比显著降低；这导致T辅助诱导细胞与细胞毒性抑制细胞的比例增加。BAL液中自然杀伤细胞的总数也减少。暴露后所有其他细胞类型的数量均未改变。未检测到体外肺泡巨噬细胞对调理酵母颗粒的吞噬作用降低。得出的结论是，反复短期暴露于1.5 ppm二氧化氮（一种中等职业浓度）会对免疫活性支气管肺泡淋巴细胞产生显著影响。这表明先前在动物中由二氧化氮诱导的淋巴免疫系统变化很可能适用于人类。
