title: Functional characteristics of the high affinity IgG receptor, FcγRI.
abstract: IgG FcRs are important mediators of immunity and play a key role during Ab-based immunotherapy. Within the leukocyte IgG receptor family, only FcγRI is capable of IgG binding with high affinity. FcγRI exists as a complex of a ligand binding α-chain and an FcR γ-chain. The receptors' α-chain can, furthermore, elicit several functions independent of the ITAM-bearing FcR γ-chain. Functional implications of high-affinity IgG binding and mechanisms underlying FcR γ-chain-independent signaling remain unclear to this day. In this paper, we provide an overview of past literature on FcγRI and address the implications of recently described interactions between cytosolic proteins and the FcγRI α-chain, as well as cytokine-enhanced FcγRI immune complex binding. Furthermore, an analysis of potential polymorphisms within the FCGR1A gene is provided.
authors.affiliation: Immunotherapy Laboratory, Department of Immunology, University Medical Center, 3584 EA Utrecht, The Netherlands.
authors.forename: Cees E
authors.initials: CE
authors.lastname: van der Poel
authors.forename: Robbert M
authors.initials: RM
authors.lastname: Spaapen
authors.forename: Jan G J
authors.initials: JG
authors.lastname: van de Winkel
authors.forename: Jeanette H W
authors.initials: JH
authors.lastname: Leusen
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D017951:Antigen Presentation / Q000235:genetics / Q000276:immunology; D000936:Antigen-Antibody Complex / Q000737:chemistry / Q000235:genetics / Q000502:physiology; D001666:Binding Sites, Antibody / Q000235:genetics; D004195:Disease Models, Animal; D006801:Humans; D008969:Molecular Sequence Data; D011485:Protein Binding / Q000235:genetics / Q000276:immunology; D017434:Protein Structure, Tertiary / Q000235:genetics; D017452:Receptors, IgG / Q000737:chemistry / Q000235:genetics / Q000502:physiology*
chemical_list: D000936:Antigen-Antibody Complex; C489017:FCGR1A protein, human; C485701:Fcgr1 protein, mouse; D017452:Receptors, IgG