title: Heterogeneous nuclear RNPs as targets of autoantibodies in systemic rheumatic diseases.
abstract: OBJECTIVE
  To investigate the abundance of autoantibodies to heterogeneous nuclear RNPs (hnRNPs) in systemic rheumatic diseases.
  
  
  METHODS
  Recombinant human hnRNPs A1, B1, C1, E1, F, Gi, H1, I, K, and P2 were prepared. Antibodies to these antigens were determined by Western blotting and by enzyme-linked immunosorbent assay (ELISA) (for hnRNPs B1, E1, F, and H1) in serum samples obtained from patients with chronic fatigue syndrome (control subjects) and from patients with various connective tissue diseases.
  
  
  RESULTS
  Western blotting analysis in 106 control subjects and 298 patients with a connective tissue disease revealed that antibodies to all tested hnRNP antigens, except hnRNP Gi, were significantly more prevalent in patients with Sjögren's syndrome (SS) than in control subjects. The highest reactivity was observed for hnRNPs B1, E1, F, and H1 (reactivity in >45% of patients with SS and in 2.8% of control subjects). Reactivity with hnRNPs B1, E1, F, and H1 was also evaluated by ELISA in 89 control subjects and 228 patients with a connective tissue disease. Reactivity with at least 2 of the 4 tested antigens was observed in 1.1% of control subjects, 16% of patients with systemic lupus erythematosus (SLE), and 18% of patients with SS. Reactivity with at least 3 of the 4 antigens was observed in 0% of the control subjects, 3.2% of patients with SLE, and 15% of patients with SS.
  
  
  CONCLUSIONS
  Several hnRNPs are target antigens in SS. The combined presence of antibodies to several hnRNPs was strongly associated with connective tissue disease in general and with SS in particular.
authors: Catholic University of Leuven, and Experimental Laboratory of Medicine, Immunology, University Hospitals Leuven, Leuven, Belgium.
authors: Katrijn
authors: K
authors: Op De Beéck
authors: Liesbeth
authors: L
authors: Maes
authors: Karolien
authors: K
authors: Van den Bergh
authors: Rita
authors: R
authors: Derua
authors: Etienne
authors: E
authors: Waelkens
authors: Kristel
authors: K
authors: Van Steen
authors: Pieter
authors: P
authors: Vermeersch
authors: René
authors: R
authors: Westhovens
authors: Kurt
authors: K
authors: De Vlam
authors: Patrick
authors: P
authors: Verschueren
authors: Herbert
authors: H
authors: Hooijkaas
authors: Daniel
authors: D
authors: Blockmans
authors: Xavier
authors: X
authors: Bossuyt
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000032:analysis / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology*; D003240:Connective Tissue Diseases / Q000097:blood / Q000235:genetics / Q000276:immunology*; D015673:Fatigue Syndrome, Chronic / Q000097:blood / Q000235:genetics / Q000276:immunology; D005260:Female; D034441:Heterogeneous-Nuclear Ribonucleoproteins / Q000097:blood / Q000276:immunology*; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000097:blood / Q000235:genetics / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011485:Protein Binding; D011994:Recombinant Proteins / Q000097:blood / Q000276:immunology; D012859:Sjogren's Syndrome / Q000097:blood / Q000235:genetics / Q000276:immunology; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D011994:Recombinant Proteins