Changes in levels of antibodies against the 70 kDa and a polypeptides of the U1RNP complex in relation to exacerbations of systemic lupus erythematosus

J Rheumatol. 1991 Mar;18(3):363-7.


In order to investigate whether disease exacerbations of systemic lupus erythematosus (SLE) are accompanied or preceded by changes in antibody levels against the U1RNA associated 70 kDa and A polypeptides, we prospectively collected plasma specimens from 71 patients with SLE. We compared changes in anti-70 kDa/anti-A levels, measured by ELISA using cloned antigens, with changes in levels of anti-dsDNA and total IgG. Measurable levels of anti-70 kDa (n = 10) and/or anti-A antibodies (n = 6) were detected during 10 exacerbations. Four of the 10 exacerbations with a measurable level of anti-70 kDa antibodies were preceded by a significant rise in anti-70 kDa levels, 2 by a significant fall, while levels of anti-70 kDa did not change in the remaining 4 cases. Only one of the 6 exacerbations with detectable anti-A antibody levels was preceded by a significant rise in anti-A antibodies, while levels did not change before exacerbation in the other 5 cases. Six of the 10 exacerbations were preceded by a significant rise in anti-dsDNA; in 4 cases levels of anti-dsDNA did not change before exacerbation. In contrast to anti-dsDNA, no relation was found between changes in levels of anti-70 kDa/anti-A and changes in disease activity. Significant changes in levels of anti-70 kDa/anti-A, occurring in 6 cases, were accompanied by parallel changes in total IgG in 5 of these 6. We conclude that, in contrast to anti-dsDNA, serial measurement of levels of anti-70 kDa/anti-A is not useful for monitoring disease activity or predicting disease exacerbations in SLE.(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Antibodies, Antinuclear / analysis*
  • Antigens, Differentiation, T-Lymphocyte / immunology
  • CD3 Complex
  • CD4 Antigens / immunology
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Humans
  • Immunoglobulin G / analysis
  • Lupus Erythematosus, Systemic / immunology*
  • Male
  • Middle Aged
  • Peptide Fragments / immunology*
  • Peptides / immunology*
  • Prospective Studies
  • Receptors, Antigen, T-Cell / immunology
  • Ribonucleoproteins / immunology*
  • Ribonucleoproteins, Small Nuclear


  • Antibodies, Antinuclear
  • Antigens, Differentiation, T-Lymphocyte
  • CD3 Complex
  • CD4 Antigens
  • Immunoglobulin G
  • Peptide Fragments
  • Peptides
  • Receptors, Antigen, T-Cell
  • Ribonucleoproteins
  • Ribonucleoproteins, Small Nuclear