title: Monocyte subsets responsible for immunoglobulin G-dependent effector functions in vivo.
abstract: Immunoglobulin G (IgG) antibodies confer protection against pathogenic microorganisms, serve as therapeutics in tumor therapy, and are involved in destruction of healthy tissues during autoimmune diseases. Understanding the molecular pathways and effector cell types involved in antibody-mediated effector functions is a prerequisite to modulate these activities. In this study we used two independent model systems to identify innate immune effector cells required for IgG activity in vivo. We first defined the precise repertoire of receptors for the IgG Fc fragment (FcγR) on innate immune effector cells in the blood and on tissue-resident macrophage populations. Despite expression of relevant activating FcγRs on various phagocyte populations, our data indicate that the majority of these cell types are dispensable for IgG activity in vivo. In contrast, IgG-dependent effector functions were selectively impaired in animals lacking the CX(3)CR1(hi)Ly6C(lo)CD11c(int) monocyte subset, which expressed the full set of FcγRs required for IgG activity.
authors.affiliation: Department of Biology, University of Erlangen-Nuremberg, Erwin-Rommel-Str. 3, 91058 Erlangen, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Biburger
authors.forename: Susanne
authors.initials: S
authors.lastname: Aschermann
authors.forename: Inessa
authors.initials: I
authors.lastname: Schwab
authors.forename: Anja
authors.initials: A
authors.lastname: Lux
authors.forename: Heike
authors.initials: H
authors.lastname: Albert
authors.forename: Heike
authors.initials: H
authors.lastname: Danzer
authors.forename: Melissa
authors.initials: M
authors.lastname: Woigk
authors.forename: Diana
authors.initials: D
authors.lastname: Dudziak
authors.forename: Falk
authors.initials: F
authors.lastname: Nimmerjahn
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000378:metabolism; D001792:Blood Platelets / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D006098:Granulocytes / Q000276:immunology; D007113:Immunity, Innate; D007141:Immunoglobulin Fc Fragments / Q000276:immunology / Q000378:metabolism; D007074:Immunoglobulin G / Q000276:immunology / Q000378:metabolism / Q000502:physiology*; D008212:Lymphocyte Depletion; D008264:Macrophages / Q000276:immunology / Q000378:metabolism; D008407:Mast Cells / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009000:Monocytes / Q000145:classification / Q000276:immunology* / Q000378:metabolism; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000276:immunology / Q000378:metabolism; D017452:Receptors, IgG / Q000276:immunology / Q000378:metabolism
chemical_list: D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G; D017452:Receptors, IgG