Decreased Immunoglobulin G Core Fucosylation, A Player in Antibody-dependent Cell-mediated Cytotoxicity, is Associated with Autoimmune Thyroid Diseases
Tiphaine Martin, Mirna Šimurina, Marta Ząbczyńska, Marina Martinić Kavur, Magdalena Rydlewska, Marija Pezer, Kamila Kozłowska, Andrea Burri, Marija Vilaj, Renata Turek-Jabrocka, Milena Krnjajić-Tadijanović, Małgorzata Trofimiuk–Müldner, Ivo Ugrina, Anna Lityń́ska, Alicja Hubalewska‐Dydejczyk, Irena Trbojević‐Akmačić, Ee Mun Lim, John P. Walsh, Ewa Pocheć, Tim D. Spector, Scott G. Wilson, Gordan Lauc
Abstract
Autoimmune thyroid diseases (AITD) are the most common group of autoimmune diseases, associated with lymphocyte infiltration and the production of thyroid autoantibodies, like thyroid peroxidase antibodies (TPOAb), in the thyroid gland. Immunoglobulins and cell-surface receptors are glycoproteins with distinctive glycosylation patterns that play a structural role in maintaining and modulating their functions. We investigated associations of total circulating IgG and peripheral blood mononuclear cells glycosylation with AITD and the influence of genetic background in a case-control study with several independent cohorts and over 3,000 individuals in total. The study revealed an inverse association of IgG core fucosylation with TPOAb and AITD, as well as decreased peripheral blood mononuclear cells antennary α1,2 fucosylation in AITD, but no shared genetic variance between AITD and glycosylation. These data suggest that the decreased level of IgG core fucosylation is a risk factor for AITD that promotes antibody-dependent cell-mediated cytotoxicity previously associated with TPOAb levels.