title: Peritoneal injection of fucoidan suppresses the increase of plasma IgE induced by OVA-sensitization.
abstract: We previously reported that fucoidan, a dietary fiber purified from seaweed, inhibited IgE production by B cells in vitro. In this study, we examined the effect of fucoidan on IgE production in vivo. The OVA-induced increase of plasma IgE was significantly suppressed when fucoidan was intraperitoneally, but not orally, administered prior to the first immunization with OVA. The production of IL-4 and IFN-gamma in response to OVA in spleen cells isolated from OVA-sensitized mice treated with fucoidan in vivo was lower than that from mice treated without fucoidan. Moreover, the flow cytometric analysis and ELISpot assay revealed that the administration of fucoidan suppressed a number of IgE-expressing and IgE-secreting B cells, respectively. These results indicate that fucoidan inhibits the increase of plasma IgE through the suppression of IgE-producing B cell population, and the effect of fucoidan in vivo is crucially dependent on the route and timing of its administration.
authors.affiliation: Department of Dermatology, Division of Molecular Medical Science, Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3, Kasumi, Minami-ku, Hiroshima, Japan.
authors.forename: Yuhki
authors.initials: Y
authors.lastname: Yanase
authors.forename: Takaaki
authors.initials: T
authors.lastname: Hiragun
authors.forename: Kazue
authors.initials: K
authors.lastname: Uchida
authors.forename: Kaori
authors.initials: K
authors.lastname: Ishii
authors.forename: Souichi
authors.initials: S
authors.lastname: Oomizu
authors.forename: Hidenori
authors.initials: H
authors.lastname: Suzuki
authors.forename: Shoji
authors.initials: S
authors.lastname: Mihara
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Iwamoto
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Matsuo
authors.forename: Nobukazu
authors.initials: N
authors.lastname: Onishi
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Kameyoshi
authors.forename: Michihiro
authors.initials: M
authors.lastname: Hide
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D005260:Female; D007073:Immunoglobulin E / Q000097:blood*; D007165:Immunosuppression Therapy; D007274:Injections, Intraperitoneal; D007371:Interferon-gamma / Q000276:immunology; D015847:Interleukin-4 / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D010047:Ovalbumin / Q000276:immunology; D011134:Polysaccharides / Q000008:administration & dosage*
chemical_list: D011134:Polysaccharides; D015847:Interleukin-4; D007073:Immunoglobulin E; D007371:Interferon-gamma; D010047:Ovalbumin; C007789:fucoidan