Clinical evaluation of a modified ELISA, using photobiotinylated DNA, for the detection of anti-DNA antibodies

J Immunol Methods. 1994 Mar 29;170(1):93-102. doi: 10.1016/0022-1759(94)90249-6.


The measurement of anti-dsDNA antibodies is important for the diagnosis and the follow-up of patients with systemic lupus erythematosus (SLE). For routine detection of anti-dsDNA, the Farr assay and the immunofluorescence technique (IFT) on Crithidia luciliae proved to be very useful. The anti-dsDNA ELISA is not used for routine purposes in our institute since it is flawed by false-positive results due to binding of negatively charged (immune) complexes to the employed precoat (protamine sulphate). Recently, a new anti-dsDNA ELISA has been described in which photobiotinylated dsDNA is coated to streptavidin coated plates. To investigate whether this modified ELISA is more specific than the classical anti-dsDNA ELISA, we tested sera of patients with SLE (n = 51), myasthenia gravis (MG, n = 25), rheumatoid arthritis (RA, n = 25) and Sjögren's syndrome (SS, n = 23) and sera of healthy blood bank donors (BBD, n = 25). In both assays the sera of the SLE patients gave significantly higher values than the sera of healthy blood bank donors. In the classical ELISA, 84% of the sera from patients with RA and 28% of sera of patients with MG were found positive. For the modified assay the figures were 8% and 24%, respectively. This modified ELISA was further studied and clinically evaluated by comparing it with the classical anti-DNA ELISA and two other anti-DNA assays (Farr assay and IFT), using 500 sera sent to our institute for routine anti-DNA determination and sera of an additional 75 healthy blood bank donors. Quantitatively, both ELISAs showed the same high degree of correlation with the IFT. The modified ELISA gave a better correlation with the Farr assay than the classical anti-DNA ELISA. From our data we conclude that the ELISA using photobiotinylated DNA is a more reliable assay than the classical anti-DNA ELISA.

Publication types

  • Clinical Trial
  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antibodies, Antinuclear / analysis*
  • Autoimmune Diseases / immunology*
  • Biotin*
  • DNA / immunology*
  • Enzyme-Linked Immunosorbent Assay / methods*
  • Evaluation Studies as Topic
  • Fluorescent Antibody Technique
  • Humans
  • Reproducibility of Results
  • Sensitivity and Specificity


  • Antibodies, Antinuclear
  • Biotin
  • DNA