title: Changes of glycosylation of IgG in rheumatoid arthritis patients treated with methotrexate.
abstract: OBJECTIVE
  In patients with active rheumatoid arthritis (RA) decrease of galactosylation is correlated with disease activity. The aim of our study was to evaluate an effect of methotrexate therapy on glycosylation disturbances of IgG in RA patients.
  
  
  METHODS
  IgG glycosylation in 40 patients with active RA treated with methotrexate for 12 months prior to and after treatment were compared. The control group consisted of 20 healthy volunteers. IgG glycosylation was assessed using biotinylated lectins and immunosorbent ELISA assay. For galactose specificity Datura stramonium lectin (DSA), for sialic acid Sambucus nigra (SNA) and Maackia amurensis (MAA) and for fucose residue Areulia auranta (AAA) lectins were used.
  
  
  RESULTS
  In RA-cases N-glycan galactosylation and sialylation of IgG before treatment were significantly lower than in healthy subjects (for DSA, MAA lectins p<0.001 and SNA p<0.05). Significant increase of IgG galactosylation and sialylation in RA patients after therapy (for DSA, MAA and SNA lectin p<0.05) was detected. Moreover the glycosylation disturbances of N-glycan IgG were strongly associated with changes of disease activity based on disease activity score. For fucose residues significantly higher absorbency of AAA lectin in RA patients before treatment was observed compared to control subjects (p<0.05) and slightly, not significantly decreased after MTX therapy.
  
  
  CONCLUSIONS
  Defect of galactosylation of IgG in RA patients is a useful marker of disease activity that may be used for the assessment of therapy effectiveness. The role of IgG fucosylation and sialylation in RA pathogenesis has still to be determined.
authors.affiliation: Department of Rheumatology and Internal Diseases, Medical University of Bialystok, Bialystok, Poland. Electronic address: ewajsieskiewicz@op.pl.
authors.forename: Ewa
authors.initials: E
authors.lastname: Gińdzieńska-Sieśkiewicz
authors.affiliation: Department of General and Organic Chemistry, Medical University of Bialystok, Bialystok, Poland.
authors.forename: Iwona
authors.initials: I
authors.lastname: Radziejewska
authors.affiliation: Department of Rheumatology and Internal Diseases, Medical University of Bialystok, Bialystok, Poland.
authors.forename: Izabela
authors.initials: I
authors.lastname: Domysławska
authors.affiliation: Department of Rheumatology and Internal Diseases, Medical University of Bialystok, Bialystok, Poland.
authors.forename: Piotr Adrian
authors.initials: PA
authors.lastname: Klimiuk
authors.affiliation: Department of Rheumatology and Internal Diseases, Medical University of Bialystok, Bialystok, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Sulik
authors.affiliation: Department of Rheumatology and Internal Diseases, Medical University of Bialystok, Bialystok, Poland.
authors.forename: Joanna
authors.initials: J
authors.lastname: Rojewska
authors.affiliation: Department of General and Organic Chemistry, Medical University of Bialystok, Bialystok, Poland.
authors.forename: Halina
authors.initials: H
authors.lastname: Gabryel-Porowska
authors.affiliation: Department of Rheumatology and Internal Diseases, Medical University of Bialystok, Bialystok, Poland.
authors.forename: Stanisław
authors.initials: S
authors.lastname: Sierakowski
mesh_terms: D000328:Adult; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000276:immunology*; D003710:Demography; D005260:Female; D005643:Fucose / Q000378:metabolism; D005690:Galactose / Q000378:metabolism; D006031:Glycosylation / Q000187:drug effects; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism*; D037102:Lectins / Q000378:metabolism; D008297:Male; D008727:Methotrexate / Q000494:pharmacology / Q000627:therapeutic use*; D008875:Middle Aged; D019158:N-Acetylneuraminic Acid / Q000378:metabolism; D006023:Glycoproteins
chemical_list: D005643:Fucose; D005690:Galactose; D007074:Immunoglobulin G; D037102:Lectins; D008727:Methotrexate; D019158:N-Acetylneuraminic Acid; C046179:glycosylated IgG; D006023:Glycoproteins
keywords: Glycosylation; Immunoglobulin G; Methotrexate; Rheumatoid arthritis