Immediate and delayd type-allergic reactivity of disinfection by-products in drinking water

本研究的目的是阐明消毒剂和各种消毒副产物对免疫应答的影响。以前的研究发现，乙二醛和水合三氯乙醛等醛类物质能产生活性氧物种，对B细胞有丝分裂反应的抑制作用强于T细胞有丝分裂反应。近年来，采用化学介质释放指标，即大鼠嗜碱性白血病RBL-2H3细胞释放β-氨基己糖苷酶，研究了有机消毒副产物对即刻变态反应的影响。在亲和素与生物素标记的小鼠抗DNP IgE抗体的复合体刺激脱颗粒条件下，DBPs对β-氨基己糖苷酶的释放无影响。在正常条件下，二氯乙醛、2，4-二氯苯酚和2，4，6-三氯苯酚对β-氨基己糖苷酶的释放有微弱的促进作用。为了阐明氯化副产物作为混合物对IgE抗体产生的佐剂活性，给小鼠腹腔注射DNP-OVA和/或氯化腐植酸-XAD4/8浓缩物。联合应用弗氏不完全佐剂作为阳性对照可促进抗DNP-OVA抗体的产生，但联合应用氯化腐植酸浓缩液可降低抗体的产生。与单独给予DNP-OVA相比，DNP-OVA和氯化腐植酸浓缩物联合给药可提高小鼠脾细胞中B/T细胞的比例。这些结果表明，氯化副产物影响免疫反应，氯化腐植酸浓缩物，因为它们的混合物更可能抑制免疫反应。

The purpose of this study is to clarify the effects of disinfectants and various disinfection by-products (DBPs) on immune response. In the previous study, aldehydes such as glyoxal and chloral hydrate were found to generate active oxygen species and show more inhibitory action to B-cell mitogenic response than T-cell mitogenic response. In the current year, organic disinfection by-products (DBPs) were investigated for effects on immediate allergic reaction using an index of chemical mediator release, that is the release of beta-hexosaminidase from rat basophilic leukemia RBL-2H3 cells. In the stimulated degranulation condition with the complex of avidin and biotinylated mouse anti-DNP IgE antibody, none of DBPs affected the release of beta-hexosaminidase. In the normal condition, however, dichloroacetaldehyde, 2,4-dichlorophenol and 2,4,6-trichloro-phenol showed weak promoting action on the release of beta-hexosaminidase. To elucidate adjuvant activity of chlorination by-products as a mixture on IgE antibody production, mice were administered intraperitoneally with DNP-OVA and/or chlorinated humic acid-XAD 4/8-concentrate. The anti-DNP IgE antibody production to DNP-OVA was enhanced by the co-administration of Freund's incomplete adjuvant as a positive control, but rather lowered by the co-administration of chlorinated humic acid concentrate. The B/T cell ratio in spleen cells was elevated by the co-administration of DNP-OVA and chlorinated humic acid concentrate, compared to the case of the administration of DNP-OVA only. These results indicate that chlorination by-products affect immune responses and chlorinated humic acid concentrate as their mixture may rather suppress immune reaction.