title: TCDD exposure exacerbates atopic dermatitis-related inflammation in NC/Nga mice.
abstract: Our previous study showed that 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) exposure of NC/Nga mice, a mouse model of atopic dermatitis, induces no dermal changes. In the present study, to investigate whether TCDD exacerbates atopic dermatitis-like skin lesions elicited in NC/Nga mice, NC/Nga mice were applied with picryl chloride (PC), and then were exposed to a single oral dose of 0 (control), 5, and 20 microg TCDD/kg. Two weeks later, spleens, blood, and skin specimens were collected. TCDD exposure increased the production of Th1-type cytokine IFN-gamma, but not Th2-type cytokine IL-4, from spleen cells stimulated with a mitogen. The plasma total IgE antibody levels of the TCDD-exposed mice remained at control levels. On the other hand, TCDD exposure markedly increased the mast cell infiltration and degranulation in PC-sensitized NC/Nga mice histologically, as compared with control mice. These results suggest that TCDD exposure exacerbates atopic dermatitis-related inflammation with no increase of IgE antibody production and that TCDD may be one of the environmental pollutants that induce exacerbations of atopic diseases.
authors.affiliation: Environmental Health Sciences Division, National Institute for Environmental Studies, Tsukuba, Ibaraki, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Ito
authors.forename: Kaoru
authors.initials: K
authors.lastname: Inouye
authors.forename: Keiko
authors.initials: K
authors.lastname: Nohara
authors.forename: Chiharu
authors.initials: C
authors.lastname: Tohyama
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Fujimaki
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism; D003876:Dermatitis, Atopic / Q000139:chemically induced* / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D054644:Ear Auricle / Q000187:drug effects / Q000473:pathology; D004785:Environmental Pollutants / Q000633:toxicity*; D007073:Immunoglobulin E / Q000097:blood; D051379:Mice; D008815:Mice, Inbred Strains; D009929:Organ Size / Q000187:drug effects; D010853:Picryl Chloride / Q000633:toxicity; D000072317:Polychlorinated Dibenzodioxins / Q000633:toxicity*; D012867:Skin / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D013154:Spleen / Q000187:drug effects / Q000473:pathology
chemical_list: D016207:Cytokines; D004785:Environmental Pollutants; D000072317:Polychlorinated Dibenzodioxins; D007073:Immunoglobulin E; D010853:Picryl Chloride