title: A novel Fc receptor for IgA and IgM is expressed on both hematopoietic and non-hematopoietic tissues.
abstract: By contrast to well-defined Fc gamma and Fc epsilon receptors, the structural and functional characteristics of Fc mu receptor are unclear. We have recently described a novel mouse Fc receptor, designated Fc alpha/mu receptor, and its human homologue, which bind both IgM and IgA. Here we show that the Fc alpha/mu receptor is expressed on mature, but not immature, B lymphocytes and acquires the ability to bind IgM and IgA antibodies after stimulation of B lymphocytes. Moreover, stimulation with phorbol 12-myristate 13-acetate increased endocytosis of IgM-coated microparticles mediated by the Fc alpha/mu receptor expressed on pro-B cell line Ba/F3 cells. We also show that the Fc alpha/mu receptor is expressed in secondary lymphoid organs, such as lymph node and appendix, kidney and intestine, suggesting an important role of the receptor for immunity in these organs.
authors.affiliation: Department of Immunology, Institute of Basic Medical Sciences, University of Tsukuba, Ibaraki, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Sakamoto
authors.forename: K
authors.initials: K
authors.lastname: Shibuya
authors.forename: Y
authors.initials: Y
authors.lastname: Shimizu
authors.forename: K
authors.initials: K
authors.lastname: Yotsumoto
authors.forename: T
authors.initials: T
authors.lastname: Miyabayashi
authors.forename: S
authors.initials: S
authors.lastname: Sakano
authors.forename: T
authors.initials: T
authors.lastname: Tsuji
authors.forename: E
authors.initials: E
authors.lastname: Nakayama
authors.forename: H
authors.initials: H
authors.lastname: Nakauchi
authors.forename: A
authors.initials: A
authors.lastname: Shibuya
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D001854:Bone Marrow Cells / Q000276:immunology / Q000378:metabolism*; D002460:Cell Line; D004705:Endocytosis / Q000187:drug effects; D005434:Flow Cytometry; D006801:Humans; D007070:Immunoglobulin A / Q000276:immunology*; D007075:Immunoglobulin M / Q000276:immunology*; D051379:Mice; D008863:Microspheres; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D011961:Receptors, Fc / Q000276:immunology* / Q000378:metabolism*; D013154:Spleen / Q000166:cytology / Q000276:immunology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014162:Transfection
chemical_list: D007070:Immunoglobulin A; D007075:Immunoglobulin M; D012333:RNA, Messenger; D011961:Receptors, Fc; D013755:Tetradecanoylphorbol Acetate