title: Control of B Cell Responsiveness by Isotype and Structural Elements of the Antigen Receptor.
abstract: Expression of a functional B cell antigen receptor (BCR) plays a central role in regulating B cell development, maturation, and effector functions. Although IgM is solely expressed in immature B cell stages, the presence of both IgM- and IgD-BCR isotypes on mature naïve B cells raises the question of whether IgD has a unique role in B cell activation and function. While earlier studies suggested a broad functional redundancy between IgM and IgD, recent data point to an important immune regulatory role of IgD. Herein, we review these findings and discuss how the structural flexibility, mode of antigen binding, and co-receptor interactions, enable the IgD-BCR to act as a 'rheostat', regulating the activation and function of mature naïve B cells.
authors.affiliation: Institute of Immunology, University Hospital Ulm, 89081 Ulm, Germany.
authors.forename: Elias
authors.initials: E
authors.lastname: Hobeika
authors.affiliation: Department of Molecular Immunology, Faculty of Biology, Albert-Ludwigs University of Freiburg, 79104 Freiburg, Germany; Max-Planck-Institute of Immunobiology and Epigenetics, 79108 Freiburg, Germany; Center for Biological Signaling Studies (BIOSS), Albert-Ludwigs University of Freiburg, 79104 Freiburg, Germany.
authors.forename: Palash Chandra
authors.initials: PC
authors.lastname: Maity
authors.affiliation: Institute of Immunology, University Hospital Ulm, 89081 Ulm, Germany; Department of Molecular Immunology, Faculty of Biology, Albert-Ludwigs University of Freiburg, 79104 Freiburg, Germany. Electronic address: hassan.jumaa@uni-ulm.de.
authors.forename: Hassan
authors.initials: H
authors.lastname: Jumaa
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D002454:Cell Differentiation; D006801:Humans; D056724:Immunity, Humoral; D007072:Immunoglobulin D / Q000378:metabolism; D007132:Immunoglobulin Isotypes / Q000276:immunology; D007075:Immunoglobulin M / Q000378:metabolism; D056747:Immunomodulation; D008213:Lymphocyte Activation; D011947:Receptors, Antigen, B-Cell / Q000235:genetics / Q000378:metabolism*; D013329:Structure-Activity Relationship
chemical_list: D007072:Immunoglobulin D; D007132:Immunoglobulin Isotypes; D007075:Immunoglobulin M; D011947:Receptors, Antigen, B-Cell