title: The antihistamine olopatadine regulates T cell activation in palladium allergy.
abstract: Because of its corrosion resistance palladium (Pd) has been widely used in many consumer products ranging from fashion accessories to dental materials. Recently, however, an increase in Pd allergy cases has been reported. Metal allergy is categorized as a Type IV allergy, which is characterized as a delayed-type hypersensitivity reaction in which T cells are known to play an important role; however, the precise mechanism of their action remains unclear. Here we defined the relationship between histamine and the Pd allergic reaction specifically with respect to T cell responses. To verify the effects of histamine on T cells, we examined whether there is a change in IFN-γ production following stimulation of histamine or the antihistamine, olopatadine hydrochloride (OLP), in vitro. In addition, we assessed whether OLP administration affected the degree of footpad swelling or IFN-γ production during the Pd allergy response in mice. We found that histamine stimulation increased IFN-γ production in T cells, specifically enhancing IFN-γ production in CD8(+) T cells compared with CD4(+) T cells. Interestingly, OLP suppressed the production of IFN-γ in CD8(+) T cells, and this compound inhibited footpad swelling and IFN-γ production in mice with Pd allergy. These results suggest that histamine promotes the Type IV allergic reaction and thus, the histamine 1 receptor (H1R) might be useful therapeutic target for treatment of metal allergy.
authors.affiliation: Department of Immunobiology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan; Department of Oral Medicine, Oral and Maxillofacial Surgery, Tokyo Dental College, Tokyo, Japan.
authors.forename: Naohiko
authors.initials: N
authors.lastname: Iguchi
authors.affiliation: Department of Immunobiology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Takeda
authors.affiliation: Department of Immunobiology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Sato
authors.affiliation: Department of Oral Medicine, Oral and Maxillofacial Surgery, Tokyo Dental College, Tokyo, Japan.
authors.forename: Kenichirou
authors.initials: K
authors.lastname: Ukichi
authors.affiliation: Department of Oral Pathobiological Science and Surgery, Tokyo Dental College, Tokyo, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Katakura
authors.affiliation: Department of Materials Processing, Graduate School of Engineering, Tohoku University, Sendai, Japan.
authors.forename: Kyosuke
authors.initials: K
authors.lastname: Ueda
authors.affiliation: Department of Materials Processing, Graduate School of Engineering, Tohoku University, Sendai, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Narushima
authors.affiliation: Department of Immunobiology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan.
authors.forename: Shigehito
authors.initials: S
authors.lastname: Higuchi
authors.affiliation: Department of Immunobiology, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Japan. Electronic address: ogasawara@idac.tohoku.ac.jp.
authors.forename: Kouetsu
authors.initials: K
authors.lastname: Ogasawara
mesh_terms: D000485:Allergens / Q000276:immunology; D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D002478:Cells, Cultured; D006632:Histamine / Q000276:immunology; D006634:Histamine H1 Antagonists / Q000627:therapeutic use*; D006801:Humans; D006968:Hypersensitivity, Delayed / Q000188:drug therapy* / Q000276:immunology; D007371:Interferon-gamma / Q000378:metabolism; D008213:Lymphocyte Activation / Q000187:drug effects; D051379:Mice; D008807:Mice, Inbred BALB C; D000069605:Olopatadine Hydrochloride / Q000627:therapeutic use*; D010165:Palladium / Q000276:immunology; D011969:Receptors, Histamine H1 / Q000378:metabolism
chemical_list: D000485:Allergens; D006634:Histamine H1 Antagonists; D011969:Receptors, Histamine H1; D000069605:Olopatadine Hydrochloride; D010165:Palladium; D006632:Histamine; D007371:Interferon-gamma
keywords: Histamine; Histamine 1 receptor (H1R); Olopatadine hydrochloride (OLP); Palladium allergy