Patients with anti-Jo1 antibodies display a characteristic IgG Fc-glycan profile which is further enhanced in anti-Jo1 autoantibodies

Sci Rep. 2018 Dec 18;8(1):17958. doi: 10.1038/s41598-018-36395-z.

Abstract

IgG Fc-glycans affect IgG function and are altered in autoimmune diseases and autoantibodies. Anti-histidyl tRNA synthetase autoantibodies (anti-Jo1) are frequent in patients with idiopathic inflammatory myopathies (IIM) and anti-synthetase syndrome (ASS) with associated interstitial lung disease (ILD). Thus, we hypothesized that the total-IgG Fc-glycans from Jo1+ versus Jo1- patients and anti-Jo1-IgG would show characteristic differences, and that particular Fc-glycan features would be associated with specific clinical manifestations. By proteomics based mass spectrometry we observed a high abundance of agalactosylated IgG1 Fc-glycans in ASS/IIM patients (n = 44) compared to healthy age matched controls (n = 24). Using intra-individual normalization of the main agalactosylated glycan (FA2) of IgG1 vs FA2-IgG2, ASS/IIM and controls were distinguished with an area under the curve (AUC) of 79 ± 6%. For Jo1+ patients (n = 19) the AUCs went up to 88 ± 6%. Bisected and afucosylated Fc-glycans were significantly lower in Jo1+ compared to Jo1- patients. Anti-Jo1-IgG enriched from eleven patients contained even significantly lower abundances of bisected, afucosylated and galactosylated forms compared to matched total-IgG. ASS and ILD diagnosis, as well as lysozyme and thrombospondin correlated with Jo1+ characteristic Fc-glycan features. These results suggest that the anti-Jo1+ patient Fc-glycan profile contains phenotype specific features which may underlie the pathogenic role of Jo1 autoantibodies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Autoantibodies / blood
  • Autoantibodies / immunology*
  • Autoantibodies / metabolism
  • Autoantigens / immunology*
  • Autoimmune Diseases / diagnosis
  • Autoimmune Diseases / immunology
  • Autoimmune Diseases / metabolism
  • Autoimmunity
  • Case-Control Studies
  • Female
  • Glycosylation
  • Humans
  • Immunoglobulin Fc Fragments / immunology*
  • Immunoglobulin Fc Fragments / metabolism
  • Immunoglobulin G / blood
  • Immunoglobulin G / immunology*
  • Immunoglobulin G / metabolism
  • Male
  • Middle Aged
  • Polysaccharides / metabolism

Substances

  • Autoantibodies
  • Autoantigens
  • Immunoglobulin Fc Fragments
  • Immunoglobulin G
  • Polysaccharides