TY - JOUR
T1 - Enhanced Effector Functions Due to Antibody Defucosylation Depend on the Effector Cell Fcγ Receptor Profile
AU - Bruggeman, Christine W.
AU - Dekkers, Gillian
AU - Bentlage, Arthur E. H.
AU - Treffers, Louise W.
AU - Nagelkerke, Sietse Q.
AU - Lissenberg-Thunnissen, Suzanne
AU - Koeleman, Carolien A. M.
AU - Wuhrer, Manfred
AU - van den Berg, Timo K.
AU - Rispens, Theo
AU - Vidarsson, Gestur
AU - Kuijpers, Taco W.
PY - 2017/7/1
Y1 - 2017/7/1
N2 - Abs of the IgG isotype are glycosylated in their Fc domain at a conserved asparagine at position 297. Removal of the core fucose of this glycan greatly increases the affinity for FcγRIII, resulting in enhanced FcγRIII-mediated effector functions. Normal plasma IgG contains ∼94% fucosylated Abs, but alloantibodies against, for example, Rhesus D (RhD) and platelet Ags frequently have reduced fucosylation that enhances their pathogenicity. The increased FcγRIII-mediated effector functions have been put to use in various afucosylated therapeutic Abs in anticancer treatment. To test the functional consequences of Ab fucosylation, we produced V-gene-matched recombinant anti-RhD IgG Abs of the four different subclasses (IgG1-4) with and without core fucose (i.e., 20% fucose remaining). Binding to all human FcγR types and their functional isoforms was assessed with surface plasmon resonance. All hypofucosylated anti-RhD IgGs of all IgG subclasses indeed showed enhanced binding affinity for isolated FcγRIII isoforms, without affecting binding affinity to other FcγRs. In contrast, when testing hypofucosylated anti-RhD Abs with FcγRIIIa-expressing NK cells, a 12- and 7-fold increased erythrocyte lysis was observed with the IgG1 and IgG3, respectively, but no increase with IgG2 and IgG4 anti-RhD Abs. Notably, none of the hypofucosylated IgGs enhanced effector function of macrophages, which, in contrast to NK cells, express a complex set of FcγRs, including FcγRIIIa. Our data suggest that the beneficial effects of afucosylated biologicals for clinical use can be particularly anticipated when there is a substantial involvement of FcγRIIIa-expressing cells, such as NK cells
AB - Abs of the IgG isotype are glycosylated in their Fc domain at a conserved asparagine at position 297. Removal of the core fucose of this glycan greatly increases the affinity for FcγRIII, resulting in enhanced FcγRIII-mediated effector functions. Normal plasma IgG contains ∼94% fucosylated Abs, but alloantibodies against, for example, Rhesus D (RhD) and platelet Ags frequently have reduced fucosylation that enhances their pathogenicity. The increased FcγRIII-mediated effector functions have been put to use in various afucosylated therapeutic Abs in anticancer treatment. To test the functional consequences of Ab fucosylation, we produced V-gene-matched recombinant anti-RhD IgG Abs of the four different subclasses (IgG1-4) with and without core fucose (i.e., 20% fucose remaining). Binding to all human FcγR types and their functional isoforms was assessed with surface plasmon resonance. All hypofucosylated anti-RhD IgGs of all IgG subclasses indeed showed enhanced binding affinity for isolated FcγRIII isoforms, without affecting binding affinity to other FcγRs. In contrast, when testing hypofucosylated anti-RhD Abs with FcγRIIIa-expressing NK cells, a 12- and 7-fold increased erythrocyte lysis was observed with the IgG1 and IgG3, respectively, but no increase with IgG2 and IgG4 anti-RhD Abs. Notably, none of the hypofucosylated IgGs enhanced effector function of macrophages, which, in contrast to NK cells, express a complex set of FcγRs, including FcγRIIIa. Our data suggest that the beneficial effects of afucosylated biologicals for clinical use can be particularly anticipated when there is a substantial involvement of FcγRIIIa-expressing cells, such as NK cells
KW - Antibody-Dependent Cell Cytotoxicity
KW - Fucose
KW - GPI-Linked Proteins
KW - Glycosylation
KW - Humans
KW - Immunoglobulin Fc Fragments
KW - Immunoglobulin G
KW - Journal Article
KW - Killer Cells, Natural
KW - Macrophages
KW - Protein Binding
KW - Receptors, IgG
KW - Research Support, Non-U.S. Gov't
KW - Rh-Hr Blood-Group System
KW - Surface Plasmon Resonance
UR - http://www.scopus.com/inward/record.url?scp=85021112769&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85021112769&partnerID=8YFLogxK
U2 - https://doi.org/10.4049/jimmunol.1700116
DO - https://doi.org/10.4049/jimmunol.1700116
M3 - Article
C2 - 28566370
SN - 0022-1767
VL - 199
SP - 204
EP - 211
JO - Journal of immunology (Baltimore, Md.
JF - Journal of immunology (Baltimore, Md.
IS - 1
ER -