Anti-topoisomerase I (anti-Scl-70) Antibodies in Patients With Systemic Lupus Erythematosus

Arthritis Rheum. 2001 Feb;44(2):376-83. doi: 10.1002/1529-0131(200102)44:2<376::AID-ANR56>3.0.CO;2-2.

Abstract

Objective: To investigate the presence and clinical significance of anti-Scl-70 antibodies in patients with systemic lupus erythematosus (SLE).

Methods: Levels of antibodies against Scl-70 were determined by a commercial clinical enzyme-linked immunosorbent assay (ELISA) during routine evaluation. Results were verified by an additional ELISA with a characterized bovine Scl-70, by ELISA with a recombinant human topoisomerase I, by Western blot, and by double diffusion in agar gel. Disease activity was estimated retrospectively by the Systemic Lupus Activity Measure (SLAM).

Results: Of 128 consecutive SLE patients, 25% were positive for anti-Scl-70 antibody; this antibody activity was cognate in nature. No SLE patient could be classified as also having systemic sclerosis. The levels of anti-Scl-70 were significantly correlated with the SLAM score for the entire cohort (r = 0.563, P < 0.001) and for 7 individual patients with multiple longitudinal measurements (r = 0.755-0.951, P < 0.001; n = 6) (r = 0.378, P < 0.05; n = 1). A significant correlation was also found between the levels of anti-Scl-70 and anti-double-stranded DNA antibodies (r = 0.558, P < 0.001). Patients with anti-Scl-70 had significantly higher risk of pulmonary hypertension (P < 0.01) and renal involvement (P < 0.001) than patients without this antibody.

Conclusion: Anti-Scl-70 antibody is present in a significant subset of patients with SLE. For this subset, it offers a good correlate of disease activity and suggests increased risk for pulmonary hypertension and nephritis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Autoantibodies / blood
  • Blotting, Western
  • Enzyme-Linked Immunosorbent Assay
  • Humans
  • Immunoglobulin G / metabolism
  • Immunosorbent Techniques
  • Longitudinal Studies
  • Lupus Erythematosus, Systemic / blood*
  • Nuclear Proteins / immunology*
  • Protein Binding
  • Reproducibility of Results
  • Scleroderma, Systemic / blood

Substances

  • Autoantibodies
  • Immunoglobulin G
  • Nuclear Proteins
  • Scl 70 antigen, human