title: Effect of formaldehyde gas exposure in a murine allergic contact hypersensitivity model.
abstract: To clarify the effect of formaldehyde (FA) gas exposure on contact hypersensitivity (CHS), CHS reactions against 2,4,6-trinitrochlorobenzene (TNCB) was studied in BALB/c mice with a low dose of FA gas exposure. The TNCB-induced CHS reactions were slightly suppressed by the FA gas exposure immediately after sensitization, whereas they were significantly enhanced and prolonged in mice continuously exposed to FA gas before and after sensitization. We showed that exposure to FA gas enhanced the Th2 dominant responses in draining lymph node (LN) in early stage of CHS. In contrast, T cell subsets and their intracellular cytokine production in the draining LN were similar during the early stage of CHS by FA gas exposure during the sensitization phase. The percentage of CD8+ T cells was increased, and the percentage of CD4+CD25+ T cells was decreased in the FA gas-exposed group at 72 hr after elicitation. These results indicate that FA gas-exposed might influence regulatory T cells. Furthermore, in the chronic CHS model that was repetitively elicited with TNCB, more intensive and prolonged CHS reactions, and increased numbers of mast cells were found in the FA gas-exposed group at 4 hr after elicitation than in the control group, FA gas exposure may alter the intensity of allergic CHS.
authors.affiliation: Okayama University Graduate School of Medicine and Dentistry, Okayama, Japan.
authors.forename: Kazuyasu
authors.initials: K
authors.lastname: Fujii
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Tsuji
authors.forename: Hironori
authors.initials: H
authors.lastname: Matsuura
authors.forename: Fusako
authors.initials: F
authors.lastname: Okazaki
authors.forename: Sachiko
authors.initials: S
authors.lastname: Takahashi
authors.forename: Jirô
authors.initials: J
authors.lastname: Arata
authors.forename: Keiji
authors.initials: K
authors.lastname: Iwatsuki
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D017449:Dermatitis, Allergic Contact / Q000276:immunology* / Q000473:pathology* / Q000517:prevention & control; D004195:Disease Models, Animal; D004781:Environmental Exposure / Q000009:adverse effects*; D005260:Female; D005557:Formaldehyde / Q000008:administration & dosage / Q000633:toxicity*; D005740:Gases / Q000008:administration & dosage / Q000633:toxicity*; D006968:Hypersensitivity, Delayed / Q000276:immunology; D008198:Lymph Nodes / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D051379:Mice; D008807:Mice, Inbred BALB C; D010853:Picryl Chloride / Q000008:administration & dosage / Q000276:immunology; D018418:Th2 Cells / Q000187:drug effects / Q000276:immunology
chemical_list: D005740:Gases; D005557:Formaldehyde; D010853:Picryl Chloride