title: Ecklonia cava extract suppresses the high-affinity IgE receptor, FcepsilonRI expression.
abstract: Basophils and mast cells express FcepsilonRI, a high-affinity receptor for IgE, on the cell surface and act as effector cells in allergic reactions. In this study, we investigated the inhibitory effect of Ecklonia cava (EC) methanolic extract on the expression of FcepsilonRI in human basophilic KU812F cells. Flow cytometric analysis revealed that EC extract caused a concentration-dependent reduction in the cell surface expression of FcepsilonRI. The extract was also capable of reducing the binding between IgE or serum IgE and cell surface FcepsilonRI. RT-PCR analysis revealed that EC extract reduced the mRNA expression of total cellular FcepsilonRI alpha-chain. Moreover, data obtained by fluorescence spectrophotometry showed that the extract inhibited the FcepsilonRI-mediated release of histamine in a concentration-dependent manner. These results suggest that EC extract may exert its anti-allergic activity through negative-regulation of FcepsilonRI expression and a decrease in histamine release.
authors.affiliation: Institute of Marine Life Science, Pukyong National University, Busan 608-737, Republic of Korea.
authors.forename: Sun-Yup
authors.initials: SY
authors.lastname: Shim
authors.forename: Le
authors.initials: L
authors.lastname: Quang-To
authors.forename: Sang-Hoon
authors.initials: SH
authors.lastname: Lee
authors.forename: Se-Kwon
authors.initials: SK
authors.lastname: Kim
mesh_terms: D001483:Base Sequence; D015153:Blotting, Western; D002460:Cell Line; D017931:DNA Primers; D005434:Flow Cytometry; D006636:Histamine Release / Q000187:drug effects; D006801:Humans; D000459:Phaeophyceae / Q000737:chemistry*; D010936:Plant Extracts / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics; D017455:Receptors, IgE / Q000037:antagonists & inhibitors* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013050:Spectrometry, Fluorescence
chemical_list: D017931:DNA Primers; C502447:MS4A2 protein, human; D010936:Plant Extracts; D012333:RNA, Messenger; D017455:Receptors, IgE