Anti-hnRNP and other autoantibodies in systemic sclerosis with joint involvement

Rheumatology (Oxford). 2009 Aug;48(8):920-5. doi: 10.1093/rheumatology/kep138. Epub 2009 May 29.


Objectives: To investigate joint involvement in SSc and its relationship with autoantibody to the hnRNP and to anti-cyclic citrullinated peptide (anti-CCP).

Methods: Sera from 55 SSc patients were investigated. Joint involvement was determined by clinical, radiological and ultrasonographical evaluation. Anti-hnRNP proteins A1 and A2 (anti-hnRNP-A1/A2) antibodies were determined by immunoblotting. Anti-CCP, ACA, anti-topo I (ATA), Sm, U1-RNP, ribosomal RNP, Ro/SSA, La/SSB autoantibody and RF were determined.

Results: Six patients were positive for anti-hnRNP-A2 autoantibody and two were anti-A1 positive. Eight patients had joint erosions: seven of the eight patients positive for anti-hnRNP-A2 or A1 presented articular involvement (P < 0.04) and five of the eight erosive patients were positive for either of the two autoantibodies (P < 0.02). Of the four patients positive for anti-CCP, none had anti-hnRNP but three had erosive aspects. ATAs were found in 10 patients, six of which were also positive for anti-hnRNP (P < 0.05). RF was positive in 16 patients and in seven among those with articular involvement (P < 0.04). RF was significantly associated with anti-hnRNP in patients with erosive arthritis (P < 0.02), but not with the presence of anti-hnRNP alone. Epitope mapping of the three strongest anti-hnRNP-A2-positive sera recognized the same major epitope as patients with RA. SSc patients have higher incidence of erosions and anti-hnRNP-A2/A1 positivity. RF test and anti-hnRNP had a statistically significant diagnostic value for articular involvement.

Conclusions: These parameters might suggest that autoantibody to both hnRNP antigens might become a non-specific but useful marker for joint involvement in SSc patients and identify SSc patients prone to develop joint damage.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Arthrography
  • Autoantibodies / blood*
  • Autoantibodies / immunology
  • Female
  • Heterogeneous Nuclear Ribonucleoprotein A1
  • Heterogeneous-Nuclear Ribonucleoprotein Group A-B / immunology
  • Heterogeneous-Nuclear Ribonucleoproteins / immunology*
  • Humans
  • Joints / immunology*
  • Joints / pathology
  • Male
  • Middle Aged
  • Peptides, Cyclic / immunology
  • Probability
  • Scleroderma, Systemic / diagnostic imaging
  • Scleroderma, Systemic / immunology*
  • Ultrasonography


  • Autoantibodies
  • Heterogeneous Nuclear Ribonucleoprotein A1
  • Heterogeneous-Nuclear Ribonucleoprotein Group A-B
  • Heterogeneous-Nuclear Ribonucleoproteins
  • Peptides, Cyclic
  • cyclic citrullinated peptide
  • hnRNP A2