|Budget Amount *help
¥2,500,000 (Direct Cost : ¥2,500,000)
Fiscal Year 1997 : ¥1,400,000 (Direct Cost : ¥1,400,000)
Fiscal Year 1996 : ¥1,100,000 (Direct Cost : ¥1,100,000)
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.